Commit Graph

1243 Commits

Author SHA1 Message Date
Keith Mannthey
45e0b78b05 [PATCH] hot-add-mem x86_64: use CONFIG_MEMORY_HOTPLUG_RESERVE
The api for hot-add memory already has a construct for finding nodes based on
an address, memory_add_physaddr_to_nid.  This patch allows the fucntion to do
something besides return 0.  It uses the nodes_add infomation to lookup to
node info for a hot add event.

Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:18 -07:00
Keith Mannthey
53947027ad [PATCH] hot-add-mem x86_64: use CONFIG_MEMORY_HOTPLUG_SPARSE
Migate CONFIG_MEMORY_HOTPLUG to CONFIG_MEMORY_HOTPLUG_SPARSE where needed.

Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:18 -07:00
Keith Mannthey
ec69acbb11 [PATCH] hot-add-mem x86_64: Kconfig changes
Create Kconfig namespace for MEMORY_HOTPLUG_RESERVE and MEMORY_HOTPLUG_SPARSE.
 This is needed to create a disticiton between the 2 paths.  Selecting the
high level opiton of MEMORY_HOTPLUG will get you MEMORY_HOTPLUG_SPARSE if you
have sparsemem enabled or MEMORY_HOTPLUG_RESERVE if you are x86_64 with
discontig and ACPI numa support.

Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:18 -07:00
Keith Mannthey
f28c5edc06 [PATCH] hot-add-mem x86_64: fixup externs
Fix up externs in memory_hotplug.c.  Cleanup.

Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:18 -07:00
Gavin Lambert
3fcd03e070 [PATCH] NOMMU: don't try and give NULL to fput()
Don't try and give NULL to fput() in the error handling in do_mmap_pgoff()
as it'll cause an oops.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:17 -07:00
David Howells
9361401eb7 [PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer.  Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.

This patch does the following:

 (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
     support.

 (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
     an item that uses the block layer.  This includes:

     (*) Block I/O tracing.

     (*) Disk partition code.

     (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.

     (*) The SCSI layer.  As far as I can tell, even SCSI chardevs use the
     	 block layer to do scheduling.  Some drivers that use SCSI facilities -
     	 such as USB storage - end up disabled indirectly from this.

     (*) Various block-based device drivers, such as IDE and the old CDROM
     	 drivers.

     (*) MTD blockdev handling and FTL.

     (*) JFFS - which uses set_bdev_super(), something it could avoid doing by
     	 taking a leaf out of JFFS2's book.

 (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
     linux/elevator.h contingent on CONFIG_BLOCK being set.  sector_div() is,
     however, still used in places, and so is still available.

 (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
     parts of linux/fs.h.

 (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.

 (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.

 (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
     is not enabled.

 (*) fs/no-block.c is created to hold out-of-line stubs and things that are
     required when CONFIG_BLOCK is not set:

     (*) Default blockdev file operations (to give error ENODEV on opening).

 (*) Makes some /proc changes:

     (*) /proc/devices does not list any blockdevs.

     (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.

 (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.

 (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
     given command other than Q_SYNC or if a special device is specified.

 (*) In init/do_mounts.c, no reference is made to the blockdev routines if
     CONFIG_BLOCK is not defined.  This does not prohibit NFS roots or JFFS2.

 (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
     error ENOSYS by way of cond_syscall if so).

 (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
     CONFIG_BLOCK is not set, since they can't then happen.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:31 +02:00
David Howells
811d736f9e [PATCH] BLOCK: Dissociate generic_writepages() from mpage stuff [try #6]
Dissociate the generic_writepages() function from the mpage stuff, moving its
declaration to linux/mm.h and actually emitting a full implementation into
mm/page-writeback.c.

The implementation is a partial duplicate of mpage_writepages() with all BIO
references removed.

It is used by NFS to do writeback.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:26 +02:00
David Howells
831058dec3 [PATCH] BLOCK: Separate the bounce buffering code from the highmem code [try #6]
Move the bounce buffer code from mm/highmem.c to mm/bounce.c so that it can be
more easily disabled when the block layer is disabled.

!!!NOTE!!! There may be a bug in this code: Should init_emergency_pool() be
	   contingent on CONFIG_HIGHMEM?

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:32:11 +02:00
David Howells
b398f6bff9 [PATCH] BLOCK: Stop fallback_migrate_page() from using page_has_buffers() [try #6]
Stop fallback_migrate_page() from using page_has_buffers() since that might not
be available.  Use PagePrivate() instead since that's more general.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:31:20 +02:00
David Howells
cf9a2ae8d4 [PATCH] BLOCK: Move functions out of buffer code [try #6]
Move some functions out of the buffering code that aren't strictly buffering
specific.  This is a precursor to being able to disable the block layer.

 (*) Moved some stuff out of fs/buffer.c:

     (*) The file sync and general sync stuff moved to fs/sync.c.

     (*) The superblock sync stuff moved to fs/super.c.

     (*) do_invalidatepage() moved to mm/truncate.c.

     (*) try_to_release_page() moved to mm/filemap.c.

 (*) Moved some related declarations between header files:

     (*) declarations for do_invalidatepage() and try_to_release_page() moved
     	 to linux/mm.h.

     (*) __set_page_dirty_buffers() moved to linux/buffer_head.h.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:31:19 +02:00
Andreas Gruenbacher
39f0247d38 [PATCH] Access Control Lists for tmpfs
Add access control lists for tmpfs.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:24 -07:00
Hugh Dickins
3f9e7949f8 [PATCH] valid_swaphandles() fix
akpm draws my attention to the fact that sysctl(VM_PAGE_CLUSTER) might
conceivably change page_cluster to 0 while valid_swaphandles() is in the
middle of using it, leading to an embarrassingly long loop: take a local
snapshot of page_cluster and work with that.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:23 -07:00
Chandra Seetharaman
2d1d43f6a4 [PATCH] call mm/page-writeback.c:set_ratelimit() when new pages are hot-added
ratelimit_pages in page-writeback.c is recalculated (in set_ratelimit())
every time a CPU is hot-added/removed.  But this value is not recalculated
when new pages are hot-added.

This patch fixes that problem by calling set_ratelimit() when new pages
are hot-added.

[akpm@osdl.org: cleanups]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:22 -07:00
Chandra Seetharaman
40c99aae23 [PATCH] remove static variable mm/page-writeback.c:total_pages
page-writeback.c has a static local variable "total_pages", which is the
total number of pages in the system.

There is a global variable "vm_total_pages", which is the total number of
pages the VM controls.

Both are assigned from the return value of nr_free_pagecache_pages().

This patch removes the local variable and uses the global variable in that
place.

One more issue with the local static variable "total_pages" is that it is
not updated when new pages are hot-added.  Since vm_total_pages is updated
when new pages are hot-added, this patch fixes that problem too.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:22 -07:00
Paul Jackson
38837fc75a [PATCH] cpuset: top_cpuset tracks hotplug changes to node_online_map
Change the list of memory nodes allowed to tasks in the top (root) nodeset
to dynamically track what cpus are online, using a call to a cpuset hook
from the memory hotplug code.  Make this top cpus file read-only.

On systems that have cpusets configured in their kernel, but that aren't
actively using cpusets (for some distros, this covers the majority of
systems) all tasks end up in the top cpuset.

If that system does support memory hotplug, then these tasks cannot make
use of memory nodes that are added after system boot, because the memory
nodes are not allowed in the top cpuset.  This is a surprising regression
over earlier kernels that didn't have cpusets enabled.

One key motivation for this change is to remain consistent with the
behaviour for the top_cpuset's 'cpus', which is also read-only, and which
automatically tracks the cpu_online_map.

This change also has the minor benefit that it fixes a long standing,
little noticed, minor bug in cpusets.  The cpuset performance tweak to
short circuit the cpuset_zone_allowed() check on systems with just a single
cpuset (see 'number_of_cpusets', in linux/cpuset.h) meant that simply
changing the 'mems' of the top_cpuset had no affect, even though the change
(the write system call) appeared to succeed.  With the following change,
that write to the 'mems' file fails -EACCES, and the 'mems' file stubbornly
refuses to be changed via user space writes.  Thus no one should be mislead
into thinking they've changed the top_cpusets's 'mems' when in affect they
haven't.

In order to keep the behaviour of cpusets consistent between systems
actively making use of them and systems not using them, this patch changes
the behaviour of the 'mems' file in the top (root) cpuset, making it read
only, and making it automatically track the value of node_online_map.  Thus
tasks in the top cpuset will have automatic use of hot plugged memory nodes
allowed by their cpuset.

[akpm@osdl.org: build fix]
[bunk@stusta.de: build fix]
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:21 -07:00
Nick Piggin
b78483a4ba [PATCH] oom: don't kill current when another OOM in progress
A previous patch to allow an exiting task to OOM kill itself (and thereby
avoid a little deadlock) introduced a problem.  We don't want the
PF_EXITING task, even if it is 'current', to access mem reserves if there
is already a TIF_MEMDIE process in the system sucking up reserves.

Also make the commenting a little bit clearer, and note that our current
scheme of effectively single threading the OOM killer is not itself
perfect.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:21 -07:00
Oleg Nesterov
01017a2270 [PATCH] oom_kill_task(): cleanup ->mm checks
- It is not possible to have task->mm == &init_mm.

- task_lock() buys nothing for 'if (!p->mm)' check.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:21 -07:00
Oleg Nesterov
972c4ea59c [PATCH] select_bad_process(): cleanup 'releasing' check
No logic changes, but imho easier to read.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:21 -07:00
Oleg Nesterov
28324d1df6 [PATCH] select_bad_process(): kill a bogus PF_DEAD/TASK_DEAD check
The only one usage of TASK_DEAD outside of last schedule path,

select_bad_process:

	for_each_task(p) {

		if (!p->mm)
			continue;
		...
			if (p->state == TASK_DEAD)
				continue;
		...

TASK_DEAD state is set at the end of do_exit(), this means that p->mm
was already set == NULL by exit_mm(), so this task was already rejected
by 'if (!p->mm)' above.

Note also that the caller holds tasklist_lock, this means that p can't
pass exit_notify() and then set TASK_DEAD when p->mm != NULL.

Also, remove open-coded is_init().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:21 -07:00
Oleg Nesterov
c394cc9fbb [PATCH] introduce TASK_DEAD state
I am not sure about this patch, I am asking Ingo to take a decision.

task_struct->state == EXIT_DEAD is a very special case, to avoid a confusion
it makes sense to introduce a new state, TASK_DEAD, while EXIT_DEAD should
live only in ->exit_state as documented in sched.h.

Note that this state is not visible to user-space, get_task_state() masks off
unsuitable states.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:21 -07:00
Oleg Nesterov
55a101f8f7 [PATCH] kill PF_DEAD flag
After the previous change (->flags & PF_DEAD) <=> (->state == EXIT_DEAD), we
don't need PF_DEAD any longer.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:20 -07:00
Sukadev Bhattiprolu
f400e198b2 [PATCH] pidspace: is_init()
This is an updated version of Eric Biederman's is_init() patch.
(http://lkml.org/lkml/2006/2/6/280).  It applies cleanly to 2.6.18-rc3 and
replaces a few more instances of ->pid == 1 with is_init().

Further, is_init() checks pid and thus removes dependency on Eric's other
patches for now.

Eric's original description:

	There are a lot of places in the kernel where we test for init
	because we give it special properties.  Most  significantly init
	must not die.  This results in code all over the kernel test
	->pid == 1.

	Introduce is_init to capture this case.

	With multiple pid spaces for all of the cases affected we are
	looking for only the first process on the system, not some other
	process that has pid == 1.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: <lxc-devel@lists.sourceforge.net>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:12 -07:00
Dave Jones
aa83aa40ed [PATCH] single bit flip detector
In cases where we detect a single bit has been flipped, we spew the usual
slab corruption message, which users instantly think is a kernel bug.  In a
lot of cases, single bit errors are down to bad memory, or other hardware
failure.

This patch adds an extra line to the slab debug messages in those cases, in
the hope that users will try memtest before they report a bug.

000: 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Single bit error detected. Possibly bad RAM. Run memtest86.

[akpm@osdl.org: cleanups]
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:10 -07:00
Adam Litke
79f5acf5d7 [PATCH] mm: make filemap_nopage use NOPAGE_SIGBUS
Don't open-code NOPAGE_SIGBUS.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:03 -07:00
Siddha, Suresh B
4ce072f1fa [PATCH] mm: fix a race condition under SMC + COW
Failing context is a multi threaded process context and the failing
sequence is as follows.

One thread T0 doing self modifying code on page X on processor P0 and
another thread T1 doing COW (breaking the COW setup as part of just
happened fork() in another thread T2) on the same page X on processor P1.
T0 doing SMC can endup modifying the new page Y (allocated by the T1 doing
COW on P1) but because of different I/D TLB's, P0 ITLB will not see the new
mapping till the flush TLB IPI from P1 is received.  During this interval,
if T0 executes the code created by SMC it can result in an app error (as
ITLB still points to old page X and endup executing the content in page X
rather than using the content in page Y).

Fix this issue by first clearing the PTE and flushing it, before updating
it with new entry.

Hugh sayeth:

  I was a bit sceptical, in the habit of thinking that Self Modifying Code
  must look such issues itself: but I guess there's nothing it can do to avoid
  this one.

  Fair enough, what you're changing it to is pretty much what powerpc and
  s390 were already doing, and is a more robust way of proceeding, consistent
  with how ptes are set everywhere else.

  The ptep_clear_flush is a bit heavy-handed (it's anxious to return the pte
  that was atomically cleared), but we'd have to wander through lots of arches
  to get the right minimal behaviour.  It'd also be nice to eliminate
  ptep_establish completely, now only used to define other macros/inlines: it
  always seemed obfuscation to me, what you've got there now is clearer.
  Let's put those cleanups on a TODO list.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:03 -07:00
Steven Whitehouse
185a257f2f Merge branch 'master' into gfs2 2006-09-28 08:29:59 -04:00
Steven Whitehouse
3f1a9aaeff [GFS2] Fix typo in last patch
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-27 14:52:48 -04:00
Steven Whitehouse
0e0bcae3bf [GFS2] Fix direct i/o logic in filemap.c
We shouldn't mark the file accessed in the case that it
wasn't accessed.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-09-27 14:45:07 -04:00
Theodore Ts'o
ba52de123d [PATCH] inode-diet: Eliminate i_blksize from the inode structure
This eliminates the i_blksize field from struct inode.  Filesystems that want
to provide a per-inode st_blksize can do so by providing their own getattr
routine instead of using the generic_fillattr() function.

Note that some filesystems were providing pretty much random (and incorrect)
values for i_blksize.

[bunk@stusta.de: cleanup]
[akpm@osdl.org: generic_fillattr() fix]
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:18 -07:00
David Howells
930e652a21 [PATCH] NOMMU: Make futexes work under NOMMU conditions
Make futexes work under NOMMU conditions.

This can be tested by running this in one shell:

	#define SYSERROR(X, Y) \
		do { if ((long)(X) == -1L) { perror(Y); exit(1); }} while(0)

	int main()
	{
		int shmid, tmp, *f, n;

		shmid = shmget(23, 4, IPC_CREAT|0666);
		SYSERROR(shmid, "shmget");

		f = shmat(shmid, NULL, 0);
		SYSERROR(f, "shmat");

		n = *f;
		printf("WAIT: %p{%x}\n", f, n);
		tmp = futex(f, FUTEX_WAIT, n, NULL, NULL, 0);
		SYSERROR(tmp, "futex");
		printf("WAITED: %d\n", tmp);

		tmp = shmdt(f);
		SYSERROR(tmp, "shmdt");

		exit(0);
	}

And then this in the other shell:

	#define SYSERROR(X, Y) \
		do { if ((long)(X) == -1L) { perror(Y); exit(1); }} while(0)

	int main()
	{
		int shmid, tmp, *f;

		shmid = shmget(23, 4, IPC_CREAT|0666);
		SYSERROR(shmid, "shmget");

		f = shmat(shmid, NULL, 0);
		SYSERROR(f, "shmat");

		(*f)++;
		printf("WAKE: %p{%x}\n", f, *f);
		tmp = futex(f, FUTEX_WAKE, 1, NULL, NULL, 0);
		SYSERROR(tmp, "futex");
		printf("WOKE: %d\n", tmp);

		tmp = shmdt(f);
		SYSERROR(tmp, "shmdt");

		exit(0);
	}

The first program will set up a SYSV IPC SHM segment and wait on a futex in it
for the number at the start to change.  The program will increment that number
and wake the first program up.  This leads to output of the form:

	SHELL 1			SHELL 2
	=======================	=======================
	# /dowait
	WAIT: 0xc32ac000{0}
				# /dowake
				WAKE: 0xc32ac000{1}
	WAITED: 0		WOKE: 1

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:15 -07:00
David Howells
6fa5f80bc3 [PATCH] NOMMU: Make mremap() partially work for NOMMU kernels
Make mremap() partially work for NOMMU kernels.  It may resize a VMA provided
that it doesn't exceed the size of the slab object in which the storage is
allocated that the VMA refers to.  Shareable VMAs may not be resized.

Moving VMAs (as permitted by MREMAP_MAYMOVE) is not currently supported.

This patch also makes use of the fact that the VMA list is now ordered to cut
it short when possible.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
David Howells
3034097a50 [PATCH] NOMMU: Order the per-mm_struct VMA list
Order the per-mm_struct VMA list by address so that searching it can be cut
short when the appropriate address has been exceeded.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
David Howells
d00c7b9937 [PATCH] NOMMU: Permit ptrace to ignore non-PROT_WRITE VMAs in NOMMU mode
Permit ptrace to modify a section that's non-shared but is marked
unwritable, such as is obtained by mapping the text segment of an ELF-FDPIC
executable binary with into a binary that's being ptraced[*].

[*] Under NOMMU conditions ptrace causes read-only MAP_PRIVATE mmaps to become
    totally private copies because if a private mapping was actually shared
    then the debugging setting breakpoints in it would potentially crash
    other processes.

This is done by using the VM_MAYWRITE flag rather than the VM_WRITE flag
when deciding whether to permit a write.

Without this patch a debugger can't set breakpoints in the mapped text
sections of executables that are mapped read-only private, even if the
mmap() syscall has taken a private copy because PT_PTRACED is set.

In addition, VM_MAYREAD is used instead of VM_READ for similar reasons.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
David Howells
7b4d5b8b39 [PATCH] NOMMU: Check VMA protections
Check the VMA protections in get_user_pages() against what's being asked.

This checks to see that we don't accidentally write on a non-writable VMA or
permit an I/O mapping VMA to be accessed (which may lack page structs).

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
Sonic Zhang
910e46da4b [PATCH] Check if start address is in vma region in NOMMU function get_user_pages()
In NOMMU arch, if run "cat /proc/self/mem", data from physical address 0
are read.  This behavior is different from MMU arch.  In IA32, message
"cat: /proc/self/mem: Input/output error" is reported.

This issue is rootcaused by not validate the start address in NOMMU
function get_user_pages().  Following patch solves this issue.

Signed-off-by: Sonic Zhang <sonic.adi@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
David Howells
0159b141d8 [PATCH] NOMMU: Use find_vma() rather than reimplementing a VMA search
Use find_vma() in the NOMMU version of access_process_vm() rather than
reimplementing it.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
David Howells
0ec76a110f [PATCH] NOMMU: Check that access_process_vm() has a valid target
Check that access_process_vm() is accessing a valid mapping in the target
process.

This limits ptrace() accesses and accesses through /proc/<pid>/maps to only
those regions actually mapped by a program.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:14 -07:00
Rolf Eike Beer
d24afc57d5 [PATCH] Mark __remove_vm_area() static
The function is exported but not used from anywhere else.  It's also marked as
"not for driver use" so noone out there should really care.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Rolf Eike Beer
ead04089b1 [PATCH] Fix kerneldoc comments in mm/vmalloc.c
The empty line between the short description and the first argument
description causes a section to appear twice in the generated manpage.
Also the short description should really be short: the script can't handle
multiple lines.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Randy Dunlap
423b41d773 [PATCH] mm/page_alloc: use NULL instead of 0 for ptr
Use NULL instead of 0 for pointer value, eliminate sparse warnings.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Jes Sorensen
f4b81804a2 [PATCH] do_no_pfn()
Implement do_no_pfn() for handling mapping of memory without a struct page
backing it.  This avoids creating fake page table entries for regions which
are not backed by real memory.

This feature is used by the MSPEC driver and other users, where it is
highly undesirable to have a struct page sitting behind the page (for
instance if the page is accessed in cached mode via the struct page in
parallel to the the driver accessing it uncached, which can result in data
corruption on some architectures, such as ia64).

This version uses specific NOPFN_{SIGBUS,OOM} return values, rather than
expect all negative pfn values would be an error.  It also bugs on cow
mappings as this would not work with the VM.

[akpm@osdl.org: micro-optimise]
Signed-off-by: Jes Sorensen <jes@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Christoph Lameter
5d29234362 [PATCH] zone_statistics: Use hot node instead of cold zone_pgdat
Now that we have the node in the hot zone of struct zone we can avoid
accessing zone_pgdat in zone_statistics.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Christoph Lameter
66a550308b [PATCH] Do not allocate pagesets for unpopulated zones.
We do not need to allocate pagesets for unpopulated zones.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Christoph Lameter
d5f541ed6e [PATCH] Add node to zone for the NUMA case
Add the node in order to optimize zone_to_nid.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:13 -07:00
Christoph Lameter
765c4507af [PATCH] GFP_THISNODE for the slab allocator
This patch insures that the slab node lists in the NUMA case only contain
slabs that belong to that specific node.  All slab allocations use
GFP_THISNODE when calling into the page allocator.  If an allocation fails
then we fall back in the slab allocator according to the zonelists appropriate
for a certain context.

This allows a replication of the behavior of alloc_pages and alloc_pages node
in the slab layer.

Currently allocations requested from the page allocator may be redirected via
cpusets to other nodes.  This results in remote pages on nodelists and that in
turn results in interrupt latency issues during cache draining.  Plus the slab
is handing out memory as local when it is really remote.

Fallback for slab memory allocations will occur within the slab allocator and
not in the page allocator.  This is necessary in order to be able to use the
existing pools of objects on the nodes that we fall back to before adding more
pages to a slab.

The fallback function insures that the nodes we fall back to obey cpuset
restrictions of the current context.  We do not allocate objects from outside
of the current cpuset context like before.

Note that the implementation of locality constraints within the slab allocator
requires importing logic from the page allocator.  This is a mischmash that is
not that great.  Other allocators (uncached allocator, vmalloc, huge pages)
face similar problems and have similar minimal reimplementations of the basic
fallback logic of the page allocator.  There is another way of implementing a
slab by avoiding per node lists (see modular slab) but this wont work within
the existing slab.

V1->V2:
- Use NUMA_BUILD to avoid #ifdef CONFIG_NUMA
- Exploit GFP_THISNODE being 0 in the NON_NUMA case to avoid another
  #ifdef

[akpm@osdl.org: build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Christoph Lameter
08e0f6a970 [PATCH] Add NUMA_BUILD definition in kernel.h to avoid #ifdef CONFIG_NUMA
The NUMA_BUILD constant is always available and will be set to 1 on
NUMA_BUILDs.  That way checks valid only under CONFIG_NUMA can easily be done
without #ifdef CONFIG_NUMA

F.e.

if (NUMA_BUILD && <numa_condition>) {
...
}

[akpm: not a thing we'd normally do, but CONFIG_NUMA is special: it is
 causing ifdef explosion in core kernel, so let's see if this is a comfortable
 way in whcih to control that]

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Jes Sorensen
c72419138f [PATCH] Condense output of show_free_areas()
On larger systems, the amount of output dumped on the console when you do
SysRq-M is beyond insane.  This patch is trying to reduce it somewhat as
even with the smaller NUMA systems that have hit the desktop this seems to
be a fair thing to do.

The philosophy I have taken is as follows:
 1) If a zone is empty, don't tell, we don't need yet another line
    telling us so. The information is available since one can look up
    the fact how many zones were initialized in the first place.
 2) Put as much information on a line is possible, if it can be done
    in one line, rahter than two, then do it in one. I tried to format
    the temperature stuff for easy reading.

Change show_free_areas() to not print lines for empty zones.  If no zone
output is printed, the zone is empty.  This reduces the number of lines
dumped to the console in sysrq on a large system by several thousand lines.

Change the zone temperature printouts to use one line per CPU instead of
two lines (one hot, one cold).  On a 1024 CPU, 1024 node system, this
reduces the console output by over a million lines of output.

While this is a bigger problem on large NUMA systems, it is also applicable
to smaller desktop sized and mid range NUMA systems.

Old format:

Mem-info:
Node 0 DMA per-cpu:
cpu 0 hot: high 42, batch 7 used:24
cpu 0 cold: high 14, batch 3 used:1
cpu 1 hot: high 42, batch 7 used:34
cpu 1 cold: high 14, batch 3 used:0
cpu 2 hot: high 42, batch 7 used:0
cpu 2 cold: high 14, batch 3 used:0
cpu 3 hot: high 42, batch 7 used:0
cpu 3 cold: high 14, batch 3 used:0
cpu 4 hot: high 42, batch 7 used:0
cpu 4 cold: high 14, batch 3 used:0
cpu 5 hot: high 42, batch 7 used:0
cpu 5 cold: high 14, batch 3 used:0
cpu 6 hot: high 42, batch 7 used:0
cpu 6 cold: high 14, batch 3 used:0
cpu 7 hot: high 42, batch 7 used:0
cpu 7 cold: high 14, batch 3 used:0
Node 0 DMA32 per-cpu: empty
Node 0 Normal per-cpu: empty
Node 0 HighMem per-cpu: empty
Node 1 DMA per-cpu:
[snip]
Free pages:     5410688kB (0kB HighMem)
Active:9536 inactive:4261 dirty:6 writeback:0 unstable:0 free:338168 slab:1931 mapped:1900 pagetables:208
Node 0 DMA free:1676304kB min:3264kB low:4080kB high:4896kB active:128048kB inactive:61568kB present:1970880kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 DMA32 free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 0 HighMem free:0kB min:512kB low:512kB high:512kB active:0kB inactive:0kB present:0kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 1 DMA free:1951728kB min:3280kB low:4096kB high:4912kB active:5632kB inactive:1504kB present:1982464kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
....

New format:

Mem-info:
Node 0 DMA per-cpu:
CPU    0: Hot: hi:   42, btch:   7 usd:  41   Cold: hi:   14, btch:   3 usd:   2
CPU    1: Hot: hi:   42, btch:   7 usd:  40   Cold: hi:   14, btch:   3 usd:   1
CPU    2: Hot: hi:   42, btch:   7 usd:   0   Cold: hi:   14, btch:   3 usd:   0
CPU    3: Hot: hi:   42, btch:   7 usd:   0   Cold: hi:   14, btch:   3 usd:   0
CPU    4: Hot: hi:   42, btch:   7 usd:   0   Cold: hi:   14, btch:   3 usd:   0
CPU    5: Hot: hi:   42, btch:   7 usd:   0   Cold: hi:   14, btch:   3 usd:   0
CPU    6: Hot: hi:   42, btch:   7 usd:   0   Cold: hi:   14, btch:   3 usd:   0
CPU    7: Hot: hi:   42, btch:   7 usd:   0   Cold: hi:   14, btch:   3 usd:   0
Node 1 DMA per-cpu:
[snip]
Free pages:     5411088kB (0kB HighMem)
Active:9558 inactive:4233 dirty:6 writeback:0 unstable:0 free:338193 slab:1942 mapped:1918 pagetables:208
Node 0 DMA free:1677648kB min:3264kB low:4080kB high:4896kB active:129296kB inactive:58864kB present:1970880kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0
Node 1 DMA free:1948448kB min:3280kB low:4096kB high:4912kB active:6864kB inactive:3536kB present:1982464kB pages_scanned:0 all_unreclaimable? no
lowmem_reserve[]: 0 0 0 0

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Christoph Lameter
de3083ec3e [PATCH] slab: fix kmalloc_node applying memory policies if nodeid == numa_node_id()
kmalloc_node() falls back to ___cache_alloc() under certain conditions and
at that point memory policies may be applied redirecting the allocation
away from the current node.  Therefore kmalloc_node(...,numa_node_id()) or
kmalloc_node(...,-1) may not return memory from the local node.

Fix this by doing the policy check in __cache_alloc() instead of
____cache_alloc().

This version here is a cleanup of Kiran's patch.

- Tested on ia64.
- Extra material removed.
- Consolidate the exit path if alternate_node_alloc() returned an object.

[akpm@osdl.org: warning fix]
Signed-off-by: Alok N Kataria <alok.kataria@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Nick Piggin
0fd0e6b05a [PATCH] page invalidation cleanup
Clean up the invalidate code, and use a common function to safely remove
the page from pagecache.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Andrew Morton
e129b5c23c [PATCH] vm: add per-zone writeout counter
The VM is supposed to minimise the number of pages which get written off the
LRU (for IO scheduling efficiency, and for high reclaim-success rates).  But
we don't actually have a clear way of showing how true this is.

So add `nr_vmscan_write' to /proc/vmstat and /proc/zoneinfo - the number of
pages which have been written by the vm scanner in this zone and globally.

Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Mel Gorman
fb01439c5b [PATCH] Allow an arch to expand node boundaries
Arch-independent zone-sizing determines the size of a node
(pgdat->node_spanned_pages) based on the physical memory that was
registered by the architecture.  However, when
CONFIG_MEMORY_HOTPLUG_RESERVE is set, the architecture expects that the
spanned_pages will be much larger and that mem_map will be allocated that
is used lated on memory hot-add.

This patch allows an architecture that sets CONFIG_MEMORY_HOTPLUG_RESERVE
to call push_node_boundaries() which will set the node beginning and end to
at *least* the requested boundary.

Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:12 -07:00
Mel Gorman
9c7cd6877c [PATCH] Account for holes that are outside the range of physical memory
absent_pages_in_range() made the assumption that users of the API would not
care about holes beyound the end of physical memory.  This was not the
case.  This patch will account for ranges outside of physical memory as
holes correctly.

Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:11 -07:00
Mel Gorman
0e0b864e06 [PATCH] Account for memmap and optionally the kernel image as holes
The x86_64 code accounted for memmap and some portions of the the DMA zone as
holes.  This was because those areas would never be reclaimed and accounting
for them as memory affects min watermarks.  This patch will account for the
memmap as a memory hole.  Architectures may optionally use set_dma_reserve()
if they wish to account for a portion of memory in ZONE_DMA as a hole.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:11 -07:00
Mel Gorman
c713216dee [PATCH] Introduce mechanism for registering active regions of memory
At a basic level, architectures define structures to record where active
ranges of page frames are located.  Once located, the code to calculate zone
sizes and holes in each architecture is very similar.  Some of this zone and
hole sizing code is difficult to read for no good reason.  This set of patches
eliminates the similar-looking architecture-specific code.

The patches introduce a mechanism where architectures register where the
active ranges of page frames are with add_active_range().  When all areas have
been discovered, free_area_init_nodes() is called to initialise the pgdat and
zones.  The zone sizes and holes are then calculated in an architecture
independent manner.

Patch 1 introduces the mechanism for registering and initialising PFN ranges
Patch 2 changes ppc to use the mechanism - 139 arch-specific LOC removed
Patch 3 changes x86 to use the mechanism - 136 arch-specific LOC removed
Patch 4 changes x86_64 to use the mechanism - 74 arch-specific LOC removed
Patch 5 changes ia64 to use the mechanism - 52 arch-specific LOC removed
Patch 6 accounts for mem_map as a memory hole as the pages are not reclaimable.
	It adjusts the watermarks slightly

Tony Luck has successfully tested for ia64 on Itanium with tiger_defconfig,
gensparse_defconfig and defconfig.  Bob Picco has also tested and debugged on
IA64.  Jack Steiner successfully boot tested on a mammoth SGI IA64-based
machine.  These were on patches against 2.6.17-rc1 and release 3 of these
patches but there have been no ia64-changes since release 3.

There are differences in the zone sizes for x86_64 as the arch-specific code
for x86_64 accounts the kernel image and the starting mem_maps as memory holes
but the architecture-independent code accounts the memory as present.

The big benefit of this set of patches is a sizable reduction of
architecture-specific code, some of which is very hairy.  There should be a
greater reduction when other architectures use the same mechanisms for zone
and hole sizing but I lack the hardware to test on.

Additional credit;
	Dave Hansen for the initial suggestion and comments on early patches
	Andy Whitcroft for reviewing early versions and catching numerous
		errors
	Tony Luck for testing and debugging on IA64
	Bob Picco for fixing bugs related to pfn registration, reviewing a
		number of patch revisions, providing a number of suggestions
		on future direction and testing heavily
	Jack Steiner and Robin Holt for testing on IA64 and clarifying
		issues related to memory holes
	Yasunori for testing on IA64
	Andi Kleen for reviewing and feeding back about x86_64
	Christian Kujau for providing valuable information related to ACPI
		problems on x86_64 and testing potential fixes

This patch:

Define the structure to represent an active range of page frames within a node
in an architecture independent manner.  Architectures are expected to register
active ranges of PFNs using add_active_range(nid, start_pfn, end_pfn) and call
free_area_init_nodes() passing the PFNs of the end of each zone.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Keith Mannthey" <kmannth@gmail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:11 -07:00
Alexey Dobriyan
133d205a18 [PATCH] Make kmem_cache_destroy() return void
un-, de-, -free, -destroy, -exit, etc functions should in general return
void.  Also,

There is very little, say, filesystem driver code can do upon failed
kmem_cache_destroy().  If it will be decided to BUG in this case, BUG
should be put in generic code, instead.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:11 -07:00
Alexey Dobriyan
1a1d92c10d [PATCH] Really ignore kmem_cache_destroy return value
* Rougly half of callers already do it by not checking return value
* Code in drivers/acpi/osl.c does the following to be sure:

	(void)kmem_cache_destroy(cache);

* Those who check it printk something, however, slab_error already printed
  the name of failed cache.
* XFS BUGs on failed kmem_cache_destroy which is not the decision
  low-level filesystem driver should make. Converted to ignore.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:10 -07:00
Rafael J. Wysocki
f623f0db8e [PATCH] swsusp: Fix mark_free_pages
Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing
PageNosaveFree for PageNosave pages.  This allows us to get rid of an ugly
hack in kernel/power/snapshot.c#copy_data_pages().

Additionally, the page-copying loop in copy_data_pages() is moved to an
inline function.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:59 -07:00
Andrew Morton
546e0d2719 [PATCH] swsusp: read speedup
Implement async reads for swsusp resuming.

Crufty old PIII testbox:
	15.7 MB/s -> 20.3 MB/s

Sony Vaio:
	14.6 MB/s -> 33.3 MB/s

I didn't implement the post-resume bio_set_pages_dirty().  I don't really
understand why resume needs to run set_page_dirty() against these pages.

It might be a worry that this code modifies PG_Uptodate, PG_Error and
PG_Locked against the image pages.  Can this possibly affect the resumed-into
kernel?  Hopefully not, if we're atomically restoring its mem_map?

Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Jens Axboe <axboe@suse.de>
Cc: Laurent Riffard <laurent.riffard@free.fr>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:58 -07:00
Andrew Morton
ab95416035 [PATCH] swsusp: write speedup
Switch the swsusp writeout code from 4k-at-a-time to 4MB-at-a-time.

Crufty old PIII testbox:
	12.9 MB/s -> 20.9 MB/s

Sony Vaio:
	14.7 MB/s -> 26.5 MB/s

The implementation is crude.  A better one would use larger BIOs, but wouldn't
gain any performance.

The memcpys will be mostly pipelined with the IO and basically come for free.

The ENOMEM path has not been tested.  It should be.

Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:58 -07:00
Christoph Lameter
89fa30242f [PATCH] NUMA: Add zone_to_nid function
There are many places where we need to determine the node of a zone.
Currently we use a difficult to read sequence of pointer dereferencing.
Put that into an inline function and use throughout VM.  Maybe we can find
a way to optimize the lookup in the future.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:52 -07:00
Christoph Lameter
4415cc8df6 [PATCH] Hugepages: Use page_to_nid rather than traversing zone pointers
I found two location in hugetlb.c where we chase pointer instead of using
page_to_nid().  Page_to_nid is more effective and can get the node directly
from page flags.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:52 -07:00
Ram Gupta
5a291b98b2 [PATCH] oom-kill: update comments to reflect current code
Update the comments for __oom_kill_task() to reflect the code changes.

Signed-off-by: Ram Gupta <r.gupta@astronautics.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:52 -07:00
Christoph Lameter
83e33a4711 [PATCH] zone reclaim with slab: avoid unecessary off node allocations
Minor performance fix.

If we reclaimed enough slab pages from a zone then we can avoid going off
node with the current allocation.  Take care of updating nr_reclaimed when
reclaiming from the slab.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:52 -07:00
Christoph Lameter
0ff38490c8 [PATCH] zone_reclaim: dynamic slab reclaim
Currently one can enable slab reclaim by setting an explicit option in
/proc/sys/vm/zone_reclaim_mode.  Slab reclaim is then used as a final
option if the freeing of unmapped file backed pages is not enough to free
enough pages to allow a local allocation.

However, that means that the slab can grow excessively and that most memory
of a node may be used by slabs.  We have had a case where a machine with
46GB of memory was using 40-42GB for slab.  Zone reclaim was effective in
dealing with pagecache pages.  However, slab reclaim was only done during
global reclaim (which is a bit rare on NUMA systems).

This patch implements slab reclaim during zone reclaim.  Zone reclaim
occurs if there is a danger of an off node allocation.  At that point we

1. Shrink the per node page cache if the number of pagecache
   pages is more than min_unmapped_ratio percent of pages in a zone.

2. Shrink the slab cache if the number of the nodes reclaimable slab pages
   (patch depends on earlier one that implements that counter)
   are more than min_slab_ratio (a new /proc/sys/vm tunable).

The shrinking of the slab cache is a bit problematic since it is not node
specific.  So we simply calculate what point in the slab we want to reach
(current per node slab use minus the number of pages that neeed to be
allocated) and then repeately run the global reclaim until that is
unsuccessful or we have reached the limit.  I hope we will have zone based
slab reclaim at some point which will make that easier.

The default for the min_slab_ratio is 5%

Also remove the slab option from /proc/sys/vm/zone_reclaim_mode.

[akpm@osdl.org: cleanups]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:51 -07:00
Christoph Lameter
972d1a7b14 [PATCH] ZVC: Support NR_SLAB_RECLAIMABLE / NR_SLAB_UNRECLAIMABLE
Remove the atomic counter for slab_reclaim_pages and replace the counter
and NR_SLAB with two ZVC counter that account for unreclaimable and
reclaimable slab pages: NR_SLAB_RECLAIMABLE and NR_SLAB_UNRECLAIMABLE.

Change the check in vmscan.c to refer to to NR_SLAB_RECLAIMABLE.  The
intend seems to be to check for slab pages that could be freed.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:51 -07:00
Christoph Lameter
8417bba4b1 [PATCH] Replace min_unmapped_ratio by min_unmapped_pages in struct zone
*_pages is a better description of the role of the variable.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:51 -07:00
Christoph Lameter
d00bcc98d7 [PATCH] Extract the allocpercpu functions from the slab allocator
The allocpercpu functions __alloc_percpu and __free_percpu() are heavily
using the slab allocator.  However, they are conceptually slab.  This also
simplifies SLOB (at this point slob may be broken in mm.  This should fix
it).

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:51 -07:00
Christoph Lameter
39bbcb8f88 [PATCH] mm: do not check unpopulated zones for draining and counter updates
If a zone is unpopulated then we do not need to check for pages that are to
be drained and also not for vm counters that may need to be updated.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:51 -07:00
Christoph Lameter
006d22d9bb [PATCH] Optimize free_one_page
Free one_page currently adds the page to a fake list and calls
free_page_bulk.  Fee_page_bulk takes it off again and then calles
__free_one_page.

Make free_one_page go directly to __free_one_page.  Saves list on / off and
a temporary list in free_one_page for higher ordered pages.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:51 -07:00
Siddha, Suresh B
d2e7b7d0aa [PATCH] fix potential stack overflow in mm/slab.c
On High end systems (1024 or so cpus) this can potentially cause stack
overflow. Fix the stack usage.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Lameter
980128f223 [PATCH] Define easier to handle GFP_THISNODE
In many places we will need to use the same combination of flags.  Specify
a single GFP_THISNODE definition for ease of use in gfp.h.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Lameter
1192d52641 [PATCH] Cleanup: Add zone pointer to get_page_from_freelist
There are frequent references to *z in get_page_from_freelist.

Add an explicit zone variable that can be used in all these places.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Lameter
3d99cfb5f4 [PATCH] sys_move_pages: Do not fall back to other nodes
If the user specified a node where we should move the page to then we
really do not want any other node.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Lameter
9b819d204c [PATCH] Add __GFP_THISNODE to avoid fallback to other nodes and ignore cpuset/memory policy restrictions
Add a new gfp flag __GFP_THISNODE to avoid fallback to other nodes.  This
flag is essential if a kernel component requires memory to be located on a
certain node.  It will be needed for alloc_pages_node() to force allocation
on the indicated node and for alloc_pages() to force allocation on the
current node.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Ravikiran G Thirumalai
056c62418c [PATCH] slab: fix lockdep warnings
Place the alien array cache locks of on slab malloc slab caches on a
seperate lockdep class.  This avoids false positives from lockdep

[akpm@osdl.org: build fix]
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Lameter
2ed3a4ef95 [PATCH] slab: do not panic when alloc_kmemlist fails and slab is up
It is fairly easy to get a system to oops by simply sizing a cache via
/proc in such a way that one of the chaches (shared is easiest) becomes
bigger than the maximum allowed slab allocation size.  This occurs because
enable_cpucache() fails if it cannot reallocate some caches.

However, enable_cpucache() is used for multiple purposes: resizing caches,
cache creation and bootstrap.

If the slab is already up then we already have working caches.  The resize
can fail without a problem.  We just need to return the proper error code.
F.e.  after this patch:

# echo "size-64 10000 50 1000" >/proc/slabinfo
-bash: echo: write error: Cannot allocate memory

notice no OOPS.

If we are doing a kmem_cache_create() then we also should not panic but
return -ENOMEM.

If on the other hand we do not have a fully bootstrapped slab allocator yet
then we should indeed panic since we are unable to bring up the slab to its
full functionality.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Lameter
117f6eb1d8 [PATCH] slab: extract __kmem_cache_destroy from kmem_cache_destroy
The ability to free memory allocated to a slab cache is also useful if an
error occurs during setup of a slab.  So extract the function.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:50 -07:00
Christoph Hellwig
dbe5e69d2d [PATCH] slab: optimize kmalloc_node the same way as kmalloc
[akpm@osdl.org: export fix]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Nick Piggin
da6052f7b3 [PATCH] update some mm/ comments
Let's try to keep mm/ comments more useful and up to date. This is a start.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Ravikiran G Thirumalai
e5ac9c5aec [PATCH] Add some comments to slab.c
Also, checks if we get a valid slabp_cache for off slab slab-descriptors.
We should always get this.  If we don't, then in that case we, will have to
disable off-slab descriptors for this cache and do the calculations again.
This is a rare case, so add a BUG_ON, for now, just in case.

Signed-off-by: Alok N Kataria <alok.kataria@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Heiko Carstens
dfd54cbcc0 [PATCH] bootmem: use MAX_DMA_ADDRESS instead of LOW32LIMIT
Introduce ARCH_LOW_ADDRESS_LIMIT which can be set per architecture to
override the 4GB default limit used by the bootmem allocater within
__alloc_bootmem_low() and __alloc_bootmem_low_node().  E.g.  s390 needs a
2GB limit instead of 4GB.

Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Nick Piggin
b72f160443 [PATCH] oom: more printk
Print the name of the task invoking the OOM killer.  Could make debugging
easier.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Nick Piggin
5081dde33f [PATCH] oom: kthread infinite loop fix
Skip kernel threads, rather than having them return 0 from badness.
Theoretically, badness might truncate all results to 0, thus a kernel thread
might be picked first, causing an infinite loop.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Nick Piggin
af5b912435 [PATCH] oom: swapoff tasks tweak
PF_SWAPOFF processes currently cause select_bad_process to return straight
away.  Instead, give them high priority, so we will kill them first, however
we also first ensure no parallel OOM kills are happening at the same time.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:49 -07:00
Nick Piggin
4a3ede107e [PATCH] oom: handle oom_disable exiting
Having the oomkilladj == OOM_DISABLE check before the releasing check means
that oomkilladj == OOM_DISABLE tasks exiting will not stop the OOM killer.

Moving the test down will give the desired behaviour.  Also: it will allow
them to "OOM-kill" themselves if they are exiting.  As per the previous patch,
this is required to prevent OOM killer deadlocks (and they don't actually get
killed, because they're already exiting -- they're simply allowed access to
memory reserves).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Nick Piggin
50ec3bbffb [PATCH] oom: handle current exiting
If current *is* exiting, it should actually be allowed to access reserved
memory rather than OOM kill something else.  Can't do this via a straight
check in page_alloc.c because that would allow multiple tasks to use up
reserves.  Instead cause current to OOM-kill itself which will mark it as
TIF_MEMDIE.

The current procedure of simply aborting the OOM-kill if a task is exiting can
lead to OOM deadlocks.

In the case of killing a PF_EXITING task, don't make a lot of noise about it.
This becomes more important in future patches, where we can "kill" OOM_DISABLE
tasks.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Nick Piggin
7887a3da75 [PATCH] oom: cpuset hint
cpuset_excl_nodes_overlap does not always indicate that killing a task will
not free any memory we for us.  For example, we may be asking for an
allocation from _anywhere_ in the machine, or the task in question may be
pinning memory that is outside its cpuset.  Fix this by just causing
cpuset_excl_nodes_overlap to reduce the badness rather than disallow it.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Nick Piggin
4ff1ffb487 [PATCH] oom: reclaim_mapped on oom
Potentially it takes several scans of the lru lists before we can even start
reclaiming pages.

mapped pages, with young ptes can take 2 passes on the active list + one on
the inactive list.  But reclaim_mapped may not always kick in instantly, so it
could take even more than that.

Raise the threshold for marking a zone as all_unreclaimable from a factor of 4
time the pages in the zone to 6.  Introduce a mechanism to force
reclaim_mapped if we've reached a factor 3 and still haven't made progress.

Previously, a customer doing stress testing was able to easily OOM the box
after using only a small fraction of its swap (~100MB).  After the patches, it
would only OOM after having used up all swap (~800MB).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Nick Piggin
408d85441c [PATCH] oom: use unreclaimable info
__alloc_pages currently starts shooting if page reclaim has failed to free up
swap_cluster_max pages in one run through the priorities.  This is not always
a good indicator on its own, so make use of the all_unreclaimable logic as
well: don't consider going OOM until all zones we're interested in are
unreclaimable.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Peter Zijlstra
6ddab3b9eb [PATCH] mm: swap write failure fixup
Currently we can silently drop data if the write to swap failed.  It
usually doesn't result in data-corruption because on page-in the process
will receive SIGBUS (assuming write-failure implies read-failure).

This assumption might or might not be valid.

This patch will avoid the page being discarded after a failed write.  But
will print a warning the sysadmin _should_ take to heart, if a lot of swap
space becomes un-writeable, OOM is not far off.

Tested by making the write fail 'randomly' once every 50 writes or so.

[akpm@osdl.org: printk warning fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Pekka Enberg
ca5f9703df [PATCH] slab: respect architecture and caller mandated alignment
As explained by Heiko, on s390 (32-bit) ARCH_KMALLOC_MINALIGN is set to
eight because their common I/O layer allocates data structures that need to
have an eight byte alignment.  This does not work when CONFIG_SLAB_DEBUG is
enabled because kmem_cache_create will override alignment to BYTES_PER_WORD
which is four.

So change kmem_cache_create to ensure cache alignment is always at minimum
what the architecture or caller mandates even if slab debugging is enabled.

Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Nick Piggin
db37648cd6 [PATCH] mm: non syncing lock_page()
lock_page needs the caller to have a reference on the page->mapping inode
due to sync_page, ergo set_page_dirty_lock is obviously buggy according to
its comments.

Solve it by introducing a new lock_page_nosync which does not do a sync_page.

akpm: unpleasant solution to an unpleasant problem.  If it goes wrong it could
cause great slowdowns while the lock_page() caller waits for kblockd to
perform the unplug.  And if a filesystem has special sync_page() requirements
(none presently do), permanent hangs are possible.

otoh, set_page_dirty_lock() is usually (always?) called against userspace
pages.  They are always up-to-date, so there shouldn't be any pending read I/O
against these pages.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Nick Piggin
28e4d965e6 [PATCH] mm: remove_mapping() safeness
Some users of remove_mapping had been unsafe.

Modify the remove_mapping precondition to ensure the caller has locked the
page and obtained the correct mapping.  Modify callers to ensure the
mapping is the correct one.

[hugh@veritas.com: swapper_space fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:48 -07:00
Rolf Eike Beer
bfa5bf6d64 [PATCH] Add kerneldocs for some functions in mm/memory.c
These functions are already documented quite well with long comments.  Now
add kerneldoc style header to make this turn up in everyones favorite doc
format.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Martin Peschke
7ff6f08295 [PATCH] CPU hotplug compatible alloc_percpu()
This patch splits alloc_percpu() up into two phases.  Likewise for
free_percpu().  This allows clients to limit initial allocations to online
cpu's, and to populate or depopulate per-cpu data at run time as needed:

  struct my_struct *obj;

  /* initial allocation for online cpu's */
  obj = percpu_alloc(sizeof(struct my_struct), GFP_KERNEL);

  ...

  /* populate per-cpu data for cpu coming online */
  ptr = percpu_populate(obj, sizeof(struct my_struct), GFP_KERNEL, cpu);

  ...

  /* access per-cpu object */
  ptr = percpu_ptr(obj, smp_processor_id());

  ...

  /* depopulate per-cpu data for cpu going offline */
  percpu_depopulate(obj, cpu);

  ...

  /* final removal */
  percpu_free(obj);

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Martin Schwidefsky
8bc719d3ca [PATCH] out of memory notifier
Add a notifer chain to the out of memory killer.  If one of the registered
callbacks could release some memory, do not kill the process but return and
retry the allocation that forced the oom killer to run.

The purpose of the notifier is to add a safety net in the presence of
memory ballooners.  If the resource manager inflated the balloon to a size
where memory allocations can not be satisfied anymore, it is better to
deflate the balloon a bit instead of killing processes.

The implementation for the s390 ballooner is included.

[akpm@osdl.org: cleanups]
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Christoph Lameter
19655d3487 [PATCH] linearly index zone->node_zonelists[]
I wonder why we need this bitmask indexing into zone->node_zonelists[]?

We always start with the highest zone and then include all lower zones
if we build zonelists.

Are there really cases where we need allocation from ZONE_DMA or
ZONE_HIGHMEM but not ZONE_NORMAL? It seems that the current implementation
of highest_zone() makes that already impossible.

If we go linear on the index then gfp_zone() == highest_zone() and a lot
of definitions fall by the wayside.

We can now revert back to the use of gfp_zone() in mempolicy.c ;-)

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Christoph Lameter
2f6726e54a [PATCH] Apply type enum zone_type
After we have done this we can now do some typing cleanup.

The memory policy layer keeps a policy_zone that specifies
the zone that gets memory policies applied. This variable
can now be of type enum zone_type.

The check_highest_zone function and the build_zonelists funnctionm must
then also take a enum zone_type parameter.

Plus there are a number of loops over zones that also should use
zone_type.

We run into some troubles at some points with functions that need a
zone_type variable to become -1. Fix that up.

[pj@sgi.com: fix set_mempolicy() crash]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Christoph Lameter
4e4785bcf0 [PATCH] mempolicies: fix policy_zone check
There is a check in zonelist_policy that compares pieces of the bitmap
obtained from a gfp mask via GFP_ZONETYPES with a zone number in function
zonelist_policy().

The bitmap is an ORed mask of __GFP_DMA, __GFP_DMA32 and __GFP_HIGHMEM.
The policy_zone is a zone number with the possible values of ZONE_DMA,
ZONE_DMA32, ZONE_HIGHMEM and ZONE_NORMAL. These are two different domains
of values.

For some reason seemed to work before the zone reduction patchset (It
definitely works on SGI boxes since we just have one zone and the check
cannot fail).

With the zone reduction patchset this check definitely fails on systems
with two zones if the system actually has memory in both zones.

This is because ZONE_NORMAL is selected using no __GFP flag at
all and thus gfp_zone(gfpmask) == 0. ZONE_DMA is selected when __GFP_DMA
is set. __GFP_DMA is 0x01.  So gfp_zone(gfpmask) == 1.

policy_zone is set to ZONE_NORMAL (==1) if ZONE_NORMAL and ZONE_DMA are
populated.

For ZONE_NORMAL gfp_zone(<no _GFP_DMA>) yields 0 which is <
policy_zone(ZONE_NORMAL) and so policy is not applied to regular memory
allocations!

Instead gfp_zone(__GFP_DMA) == 1 which results in policy being applied
to DMA allocations!

What we realy want in that place is to establish the highest allowable
zone for a given gfp_mask. If the highest zone is higher or equal to the
policy_zone then memory policies need to be applied. We have such
a highest_zone() function in page_alloc.c.

So move the highest_zone() function from mm/page_alloc.c into
include/linux/gfp.h.  On the way we simplify the function and use the new
zone_type that was also introduced with the zone reduction patchset plus we
also specify the right type for the gfp flags parameter.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Christoph Lameter
27bf71c2a7 [PATCH] reduce MAX_NR_ZONES: remove display of counters for unconfigured zones
eventcounters: Do not display counters for zones that are not available on an
arch

Do not define or display counters for the DMA32 and the HIGHMEM zone if such
zones were not configured.

[akpm@osdl.org: s390 fix]
[heiko.carstens@de.ibm.com: s390 fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:47 -07:00
Christoph Lameter
e53ef38d05 [PATCH] reduce MAX_NR_ZONES: make ZONE_HIGHMEM optional
Make ZONE_HIGHMEM optional

- ifdef out code and definitions related to CONFIG_HIGHMEM

- __GFP_HIGHMEM falls back to normal allocations if there is no
  ZONE_HIGHMEM

- GFP_ZONEMASK becomes 0x01 if there is no DMA32 and no HIGHMEM
  zone.

[jdike@addtoit.com: build fix]
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:46 -07:00
Christoph Lameter
fb0e7942bd [PATCH] reduce MAX_NR_ZONES: make ZONE_DMA32 optional
Make ZONE_DMA32 optional

- Add #ifdefs around ZONE_DMA32 specific code and definitions.

- Add CONFIG_ZONE_DMA32 config option and use that for x86_64
  that alone needs this zone.

- Remove the use of CONFIG_DMA_IS_DMA32 and CONFIG_DMA_IS_NORMAL
  for ia64 and fix up the way per node ZVCs are calculated.

- Fall back to prior GFP_ZONEMASK of 0x03 if there is no
  DMA32 zone.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:46 -07:00
Christoph Lameter
2f1b624868 [PATCH] reduce MAX_NR_ZONES: use enum to define zones, reformat and comment
Use enum for zones and reformat zones dependent information

Add comments explaning the use of zones and add a zones_t type for zone
numbers.

Line up information that will be #ifdefd by the following patches.

[akpm@osdl.org: comment cleanups]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:46 -07:00
Christoph Lameter
98d2b0ebda [PATCH] reduce MAX_NR_ZONES: page allocator ZONE_HIGHMEM cleanup
page allocator ZONE_HIGHMEM fixups

1. We do not need to do an #ifdef in si_meminfo since both counters
   in use are zero if !CONFIG_HIGHMEM.

2. Add #ifdef in si_meminfo_node instead to avoid referencing zone
   information for ZONE_HIGHMEM if we do not have HIGHMEM
   (may not be there after the following patches).

3. Replace the use of ZONE_HIGHMEM with MAX_NR_ZONES in build_zonelists_node

4. build_zonelists_node: Remove BUG_ON for ZONE_HIGHMEM. Zone will
   be optional soon and thus BUG_ON cannot be triggered anymore.

5. init_free_area_core: Replace a use of ZONE_HIGHMEM with NR_MAX_ZONES.

[akpm@osdl.org: cleanups]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:46 -07:00
Christoph Lameter
c1f60a5a41 [PATCH] reduce MAX_NR_ZONES: move HIGHMEM counters into highmem.c/.h
Move totalhigh_pages and nr_free_highpages() into highmem.c/.h

Move the totalhigh_pages definition into highmem.c/.h.  Move the
nr_free_highpages function into highmem.c

[yoichi_yuasa@tripeaks.co.jp: build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:46 -07:00
Christoph Lameter
182e8e2373 [PATCH] reduce MAX_NR_ZONES: make display of highmem counters conditional on CONFIG_HIGHMEM
Do not display HIGHMEM memory sizes if CONFIG_HIGHMEM is not set.

Make HIGHMEM dependent texts and make display of highmem counters optional

Some texts are depending on CONFIG_HIGHMEM.

Remove those strings and remove the display of highmem counter values if
CONFIG_HIGHMEM is not set.

[akpm@osdl.org: remove some ifdefs]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:46 -07:00
Franck Bui-Huu
f71bf0cac7 [PATCH] bootmem: miscellaneous coding style fixes
It fixes various coding style issues, specially when spaces are useless.  For
example '*' go next to the function name.

Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Franck Bui-Huu
bbc7b92e33 [PATCH] bootmem: use pfn/page conversion macros
It also creates get_mapsize() helper in order to make the code more readable
when it calculates the boot bitmap size.

Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Franck Bui-Huu
e786e86a54 [PATCH] bootmem: remove useless headers inclusions
Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Franck Bui-Huu
bb0923a668 [PATCH] bootmem: limit to 80 columns width
Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Franck Bui-Huu
69d49e681d [PATCH] bootmem: mark link_bootmem() as part of the __init section
Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Adrian Bunk
b221385bc4 [PATCH] mm/: make functions static
This patch makes the following needlessly global functions static:
 - slab.c: kmem_find_general_cachep()
 - swap.c: __page_cache_release()
 - vmalloc.c: __vmalloc_node()

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Peter Zijlstra
204ec841fb [PATCH] mm: msync() cleanup
With the tracking of dirty pages properly done now, msync doesn't need to scan
the PTEs anymore to determine the dirty status.

From: Hugh Dickins <hugh@veritas.com>

In looking to do that, I made some other tidyups: can remove several
#includes, and sys_msync loop termination not quite right.

Most of those points are criticisms of the existing sys_msync, not of your
patch.  In particular, the loop termination errors were introduced in 2.6.17:
I did notice this shortly before it came out, but decided I was more likely to
get it wrong myself, and make matters worse if I tried to rush a last-minute
fix in.  And it's not terribly likely to go wrong, nor disastrous if it does
go wrong (may miss reporting an unmapped area; may also fsync file of a
following vma).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:45 -07:00
Peter Zijlstra
ee6a645788 [PATCH] mm: fixup do_wp_page()
Wrt. the recent modifications in do_wp_page() Hugh Dickins pointed out:

  "I now realize it's right to the first order (normal case) and to the
   second order (ptrace poke), but not to the third order (ptrace poke
   anon page here to be COWed - perhaps can't occur without intervening
   mprotects)."

This patch restores the old COW behaviour for anonymous pages.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:44 -07:00
Peter Zijlstra
e88dd6c11c [PATCH] mm: small cleanup of install_page()
Smallish cleanup to install_page(), could save a memory read (haven't checked
the asm output) and sure looks nicer.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:44 -07:00
Peter Zijlstra
c1e6098b23 [PATCH] mm: optimize the new mprotect() code a bit
mprotect() resets the page protections, which could result in extra write
faults for those pages whose dirty state we track using write faults and are
dirty already.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:44 -07:00
Peter Zijlstra
edc79b2a46 [PATCH] mm: balance dirty pages
Now that we can detect writers of shared mappings, throttle them.  Avoids OOM
by surprise.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:44 -07:00
Peter Zijlstra
d08b3851da [PATCH] mm: tracking shared dirty pages
Tracking of dirty pages in shared writeable mmap()s.

The idea is simple: write protect clean shared writeable pages, catch the
write-fault, make writeable and set dirty.  On page write-back clean all the
PTE dirty bits and write protect them once again.

The implementation is a tad harder, mainly because the default
backing_dev_info capabilities were too loosely maintained.  Hence it is not
enough to test the backing_dev_info for cap_account_dirty.

The current heuristic is as follows, a VMA is eligible when:
 - its shared writeable
    (vm_flags & (VM_WRITE|VM_SHARED)) == (VM_WRITE|VM_SHARED)
 - it is not a 'special' mapping
    (vm_flags & (VM_PFNMAP|VM_INSERTPAGE)) == 0
 - the backing_dev_info is cap_account_dirty
    mapping_cap_account_dirty(vma->vm_file->f_mapping)
 - f_op->mmap() didn't change the default page protection

Page from remap_pfn_range() are explicitly excluded because their COW
semantics are already horrid enough (see vm_normal_page() in do_wp_page()) and
because they don't have a backing store anyway.

mprotect() is taught about the new behaviour as well.  However it overrides
the last condition.

Cleaning the pages on write-back is done with page_mkclean() a new rmap call.
It can be called on any page, but is currently only implemented for mapped
pages, if the page is found the be of a VMA that accounts dirty pages it will
also wrprotect the PTE.

Finally, in fs/buffers.c:try_to_free_buffers(); remove clear_page_dirty() from
under ->private_lock.  This seems to be safe, since ->private_lock is used to
serialize access to the buffers, not the page itself.  This is needed because
clear_page_dirty() will call into page_mkclean() and would thereby violate
locking order.

[dhowells@redhat.com: Provide a page_mkclean() implementation for NOMMU]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:44 -07:00
Nick Piggin
725d704eca [PATCH] mm: VM_BUG_ON
Introduce a VM_BUG_ON, which is turned on with CONFIG_DEBUG_VM.  Use this
in the lightweight, inline refcounting functions; PageLRU and PageActive
checks in vmscan, because they're pretty well confined to vmscan.  And in
page allocate/free fastpaths which can be the hottest parts of the kernel
for kbuilds.

Unlike BUG_ON, VM_BUG_ON must not be used to execute statements with
side-effects, and should not be used outside core mm code.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:44 -07:00
David Rientjes
f3ef9ead31 [PATCH] do not free non slab allocated per_cpu_pageset
Stops panic associated with attempting to free a non slab-allocated
per_cpu_pageset.

Signed-off-by: David Rientjes <rientjes@cs.washington.edu>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-25 17:38:36 -07:00
Steven Whitehouse
363e065c02 [GFS2] Fix up merge of Linus' kernel into GFS2
This fixes up a couple of conflicts when merging up with
Linus' latest kernel. This will hopefully allow GFS2 to
be more easily merged into forthcoming -mm and FC kernels
due to the "one line per header" format now used for the
kernel headers.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Conflicts:

	include/linux/Kbuild
	include/linux/kernel.h
2006-09-25 12:26:59 -04:00
Linus Torvalds
9f261e0113 Merge git://git.linux-nfs.org/pub/linux/nfs-2.6
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (74 commits)
  NFS: unmark NFS direct I/O as experimental
  NFS: add comments clarifying the use of nfs_post_op_update()
  NFSv4: rpc_mkpipe creating socket inodes w/out sk buffers
  NFS: Use SEEK_END instead of hardcoded value
  NFSv4: When mounting with a port=0 argument, substitute port=2049
  NFSv4: Poll more aggressively when handling NFS4ERR_DELAY
  NFSv4: Handle the condition NFS4ERR_FILE_OPEN
  NFSv4: Retry lease recovery if it failed during a synchronous operation.
  NFS: Don't invalidate the symlink we just stuffed into the cache
  NFS: Make read() return an ESTALE if the file has been deleted
  NFSv4: It's perfectly legal for clp to be NULL here....
  NFS: nfs_lookup - don't hash dentry when optimising away the lookup
  SUNRPC: Fix Oops in pmap_getport_done
  SUNRPC: Add refcounting to the struct rpc_xprt
  SUNRPC: Clean up soft task error handling
  SUNRPC: Handle ENETUNREACH, EHOSTUNREACH and EHOSTDOWN socket errors
  SUNRPC: rpc_delay() should not clobber the rpc_task->tk_status
  Fix a referral error Oops
  NFS: NFS_ROOT should use the new rpc_create API
  NFS: Fix up compiler warnings on 64-bit platforms in client.c
  ...

Manually resolved conflict in net/sunrpc/xprtsock.c
2006-09-23 16:58:40 -07:00
Linus Torvalds
a4c12d6c5d Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (353 commits)
  [IPV6] ADDRCONF: Mobile IPv6 Home Address support.
  [IPV6] ADDRCONF: Allow non-DAD'able addresses.
  [IPV6] NDISC: Fix is_router flag setting.
  [IPV6] ADDRCONF: Convert addrconf_lock to RCU.
  [IPV6] NDISC: Add proxy_ndp sysctl.
  [IPV6] NDISC: Set per-entry is_router flag in Proxy NA.
  [IPV6] NDISC: Avoid updating neighbor cache for proxied address in receiving NA.
  [IPV6]: Don't forward packets to proxied link-local address.
  [IPV6] NDISC: Handle NDP messages to proxied addresses.
  [NETFILTER]: PPTP conntrack: fix another GRE keymap leak
  [NETFILTER]: PPTP conntrack: fix GRE keymap leak
  [NETFILTER]: PPTP conntrack: fix PPTP_IN_CALL message types
  [NETFILTER]: PPTP conntrack: check call ID before changing state
  [NETFILTER]: PPTP conntrack: clean up debugging cruft
  [NETFILTER]: PPTP conntrack: consolidate header parsing
  [NETFILTER]: PPTP conntrack: consolidate header size checks
  [NETFILTER]: PPTP conntrack: simplify expectation handling
  [NETFILTER]: PPTP conntrack: remove unnecessary cid/pcid header pointers
  [NETFILTER]: PPTP conntrack: fix header definitions
  [NETFILTER]: PPTP conntrack: remove more dead code
  ...
2006-09-23 16:49:31 -07:00
Trond Myklebust
275a082fe9 Add a real API for dealing with blk_congestion_wait()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:54 -04:00
Linus Torvalds
6585b57240 Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart
* master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart:
  [AGPGART] Rework AGPv3 modesetting fallback.
  [AGPGART] Add suspend callback for i965
  [AGPGART] Fix number of aperture sizes in 830 gart structs.
  [AGPGART] Intel 965 Express support.
  [AGPGART] agp.h: constify struct agp_bridge_data::version
  [AGPGART] const'ify VIA AGP PCI table.
  [AGPGART] CONFIG_PM=n slim: drivers/char/agp/intel-agp.c
  [AGPGART] CONFIG_PM=n slim: drivers/char/agp/efficeon-agp.c
  [AGPGART] Const'ify the agpgart driver version.
  [AGPGART] remove private page protection map
2006-09-22 17:50:50 -07:00
David S. Miller
f034b5d4ef [XFRM]: Dynamic xfrm_state hash table sizing.
The grow algorithm is simple, we grow if:

1) we see a hash chain collision at insert, and
2) we haven't hit the hash size limit (currently 1*1024*1024 slots), and
3) the number of xfrm_state objects is > the current hash mask

All of this needs some tweaking.

Remove __initdata from "hashdist" so we can use it safely at run time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 15:08:41 -07:00
Steven Whitehouse
0bc0748dfb Merge branch 'master' into gfs2 2006-09-13 09:55:09 -04:00
Andrew Morton
016eb4a0ed [PATCH] invalidate_complete_page() race fix
If a CPU faults this page into pagetables after invalidate_mapping_pages()
checked page_mapped(), invalidate_complete_page() will still proceed to remove
the page from pagecache.  This leaves the page-faulting process with a
detached page.  If it was MAP_SHARED then file data loss will ensue.

Fix that up by checking the page's refcount after taking tree_lock.

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-08 10:22:50 -07:00
Kirill Korotaev
3a45975681 [PATCH] IA64,sparc: local DoS with corrupted ELFs
This prevents cross-region mappings on IA64 and SPARC which could lead
to system crash.  They were correctly trapped for normal mmap() calls,
but not for the kernel internal calls generated by executable loading.

This code just moves the architecture-specific cross-region checks into
an arch-specific "arch_mmap_check()" macro, and defines that for the
architectures that needed it (ia64, sparc and sparc64).

Architectures that don't have any special requirements can just ignore
the new cross-region check, since the mmap() code will just notice on
its own when the macro isn't defined.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
[ Cleaned up to not affect architectures that don't need it ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-08 08:40:46 -07:00
Dave Jones
115b384cf8 Merge ../linus 2006-09-05 17:20:21 -04:00
Steven Whitehouse
31e77ac55f Merge branch 'master' into gfs2 2006-09-04 10:31:36 -04:00
Nishanth Aravamudan
3b98b087fc [PATCH] fix NUMA interleaving for huge pages
Since vma->vm_pgoff is in units of smallpages, VMAs for huge pages have the
lower HPAGE_SHIFT - PAGE_SHIFT bits always cleared, which results in badd
offsets to the interleave functions.  Take this difference from small pages
into account when calculating the offset.  This does add a 0-bit shift into
the small-page path (via alloc_page_vma()), but I think that is negligible.
 Also add a BUG_ON to prevent the offset from growing due to a negative
right-shift, which probably shouldn't be allowed anyways.

Tested on an 8-memory node ppc64 NUMA box and got the interleaving I
expected.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01 11:39:10 -07:00
Pavel Mironchik
0b1d647a02 [PATCH] dm: work around mempool_alloc, bio_alloc_bioset deadlocks
This patch works around a complex dm-related deadlock/livelock down in the
mempool allocator.

Alasdair said:

  Several dm targets suffer from this.

  Mempools are not yet used correctly everywhere in device-mapper: they can
  get shared when devices are stacked, and some targets share them across
  multiple instances.  I made fixing this one of the prerequisites for this
  patch:

    md-dm-reduce-stack-usage-with-stacked-block-devices.patch

  which in some cases makes people more likely to hit the problem.

  There's been some progress on this recently with (unfinished) dm-crypt
  patches at:

    http://www.kernel.org/pub/linux/kernel/people/agk/patches/2.6/editing/
      (dm-crypt-move-io-to-workqueue.patch plus dependencies)

and:

  I've no problems with a temporary workaround like that, but Milan Broz (a
  new Redhat developer in the Czech Republic) has started reviewing all the
  mempool usage in device-mapper so I'm expecting we'll soon have a proper fix
  for this associated problems.  [He's back from holiday at the start of next
  week.]

For now, this sad-but-safe little patch will allow the machine to recover.

[akpm@osdl.org: rewrote changelog]
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01 11:39:09 -07:00
Christoph Lameter
df9ecaba3f [PATCH] ZVC: Scale thresholds depending on the size of the system
The ZVC counter update threshold is currently set to a fixed value of 32.
This patch sets up the threshold depending on the number of processors and
the sizes of the zones in the system.

With the current threshold of 32, I was able to observe slight contention
when more than 130-140 processors concurrently updated the counters.  The
contention vanished when I either increased the threshold to 64 or used
Andrew's idea of overstepping the interval (see ZVC overstep patch).

However, we saw contention again at 220-230 processors.  So we need higher
values for larger systems.

But the current default is already a bit of an overkill for smaller
systems.  Some systems have tiny zones where precision matters.  For
example i386 and x86_64 have 16M DMA zones and either 900M ZONE_NORMAL or
ZONE_DMA32.  These are even present on SMP and NUMA systems.

The patch here sets up a threshold based on the number of processors in the
system and the size of the zone that these counters are used for.  The
threshold should grow logarithmically, so we use fls() as an easy
approximation.

Results of tests on a system with 1024 processors (4TB RAM)

The following output is from a test allocating 1GB of memory concurrently
on each processor (Forking the process.  So contention on mmap_sem and the
pte locks is not a factor):

                       X                   MIN
TYPE:               CPUS       WALL       WALL        SYS     USER     TOTCPU
fork                   1      0.552      0.552      0.540    0.012      0.552
fork                   4      0.552      0.548      2.164    0.036      2.200
fork                  16      0.564      0.548      8.812    0.164      8.976
fork                 128      0.580      0.572     72.204    1.208     73.412
fork                 256      1.300      0.660    310.400    2.160    312.560
fork                 512      3.512      0.696   1526.836    4.816   1531.652
fork                1020     20.024      0.700  17243.176    6.688  17249.863

So a threshold of 32 is fine up to 128 processors. At 256 processors contention
becomes a factor.

Overstepping the counter (earlier patch) improves the numbers a bit:

fork                   4      0.552      0.548      2.164    0.040      2.204
fork                  16      0.552      0.548      8.640    0.148      8.788
fork                 128      0.556      0.548     69.676    0.956     70.632
fork                 256      0.876      0.636    212.468    2.108    214.576
fork                 512      2.276      0.672    997.324    4.260   1001.584
fork                1020     13.564      0.680  11586.436    6.088  11592.523

Still contention at 512 and 1020. Contention at 1020 is down by a third.
256 still has a slight bit of contention.

After this patch the counter threshold will be set to 125 which reduces
contention significantly:

fork                 128      0.560      0.548     69.776    0.932     70.708
fork                 256      0.636      0.556    143.460    2.036    145.496
fork                 512      0.640      0.548    284.244    4.236    288.480
fork                1020      1.500      0.588   1326.152    8.892   1335.044

[akpm@osdl.org: !SMP build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01 11:39:08 -07:00
Christoph Lameter
a302eb4e46 [PATCH] ZVC: Overstep counters
Increments and decrements are usually grouped rather than mixed.  We can
optimize the inc and dec functions for that case.

Increment and decrement the counters by 50% more than the threshold in
those cases and set the differential accordingly.  This decreases the need
to update the atomic counters.

The idea came originally from Andrew Morton.  The overstepping alone was
sufficient to address the contention issue found when updating the global
and the per zone counters from 160 processors.

Also remove some code in dec_zone_page_state.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01 11:39:08 -07:00
Steven Whitehouse
83b7a664a0 Merge branch 'master' into gfs2 2006-08-29 11:39:34 -04:00
Rafael J. Wysocki
b6b5bce357 [PATCH] swsusp: Fix swap_type_of
There is a bug in mm/swapfile.c#swap_type_of() that makes swsusp only be
able to use the first active swap partition as the resume device.  Fix it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Hugh Dickins <hugh@veritas.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-27 11:01:28 -07:00
Alexander Zarochentsev
1d7ea7324a [PATCH] fuse: fix error case in fuse_readpages
Don't let fuse_readpages leave the @pages list not empty when exiting
on error.

[akpm@osdl.org: kernel-doc fixes]
Signed-off-by: Alexander Zarochentsev <zam@namesys.com>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14 12:54:29 -07:00
Steven Whitehouse
ad73c67e79 Merge branch 'master' 2006-08-07 09:16:35 -04:00
KAMEZAWA Hiroyuki
ebd15302dc [PATCH] memory hotadd fixes: enhance collision check
This patch is for collision check enhancement for memory hot add.

It's better to do resouce collision check before doing memory hot add,
which will touch memory management structures.

And add_section() should check section exists or not before calling
sparse_add_one_section(). (sparse_add_one_section() will do another
check anyway. but checking in memory_hotplug.c will be easy to understand.)

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: keith mannthey <kmannth@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-06 08:57:49 -07:00
KAMEZAWA Hiroyuki
58c1b5b079 [PATCH] memory hotadd fixes: find_next_system_ram catch range fix
find_next_system_ram() is used to find available memory resource at onlining
newly added memory.  This patch fixes following problem.

find_next_system_ram() cannot catch this case.

Resource:      (start)-------------(end)
Section :                (start)-------------(end)

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Keith Mannthey <kmannth@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-06 08:57:48 -07:00
KAMEZAWA Hiroyuki
6f712711db [PATCH] memory hotadd fixes: not-aligned memory hotadd handling fix
ioresouce handling code in memory hotplug allows not-aligned memory hot add.
But when memmap and other memory structures are initialized, parameters should
be aligned.  (if not aligned, initialization of mem_map will do wrong, it
assumes parameters are aligned.) This patch fix it.

And this patch allows ioresource collision check to handle -EEXIST.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Keith Mannthey <kmannth@gmail.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-06 08:57:48 -07:00
Andrew Morton
60c371bc75 [PATCH] fadvise() make POSIX_FADV_NOREUSE a no-op
The POSIX_FADV_NOREUSE hint means "the application will use this range of the
file a single time".  It seems to be intended that the implementation will use
this hint to perform drop-behind of that part of the file when the application
gets around to reading or writing it.

However for reasons which aren't obvious (or sane?) I mapped
POSIX_FADV_NOREUSE onto POSIX_FADV_WILLNEED.  ie: it does readahead.

That's daft.  So for now, make POSIX_FADV_NOREUSE a no-op.

This is a non-back-compatible change.  If someone was using POSIX_FADV_NOREUSE
to perform readahead, they lose.  The likelihood is low.

If/when we later implement POSIX_FADV_NOREUSE things will get interesting - to
do it fully we'll need to maintain file offset/length ranges and peform all
sorts of complex tricks, and managing the lifetime of those ranges' data
structures will be interesting..

A sensible implementation would probably ignore the file range and would
simply mark the entire file as needing some form of drop-behind treatment.

Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-06 08:57:47 -07:00
Rolf Eike Beer
b8008b2bc2 [PATCH] Fix kmem_cache_alloc() been documented twice
kmem_cache_alloc() was documented twice, but kmem_cache_zalloc() never.
Fix this obvious typo to get things right.

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-31 13:28:43 -07:00
Chandra Seetharaman
8c78f3075d [PATCH] cpu hotplug: replace __devinit* with __cpuinit* for cpu notifications
Few of the callback functions and notifier blocks that are associated with cpu
notifications incorrectly have __devinit and __devinitdata.  They should be
__cpuinit and __cpuinitdata instead.

It makes no functional difference but wastes text area when CONFIG_HOTPLUG is
enabled and CONFIG_HOTPLUG_CPU is not.

This patch fixes all those instances.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-31 13:28:39 -07:00
Steven Whitehouse
b1b934d31d Merge branch 'master' 2006-07-31 08:59:59 -04:00
Andi Kleen
b83a8e64fd [PATCH] MM: Remove rogue readahead printk
For some reason it triggers always with NFS root and spams the kernel
logs of my nfs root boxes a lot.

Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-29 20:59:55 -07:00
Hugh Dickins
804af2cf6e [AGPGART] remove private page protection map
AGP keeps its own copy of the protection_map, upcoming DRM changes will
also require access to this map from modules.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Signed-off-by: Dave Jones <davej@redhat.com>
2006-07-26 19:58:39 -04:00
Steven Whitehouse
a9e5f4d078 [GFS2] Alter direct I/O path
As per comments received, alter the GFS2 direct I/O path so that
it uses the standard read functions "out of the box". Needs a
small change to one of the VFS functions. This reduces the size
of the code quite a lot and also removes the need for one new export.

Some more work remains to be done, but this is the bones of the
thing.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-07-25 17:24:12 -04:00
Steven Whitehouse
4bf311ddfb Merge branch 'master' 2006-07-17 09:25:26 -04:00
Shailabh Nagar
0ff922452d [PATCH] per-task-delay-accounting: sync block I/O and swapin delay collection
Unlike earlier iterations of the delay accounting patches, now delays are only
collected for the actual I/O waits rather than try and cover the delays seen
in I/O submission paths.

Account separately for block I/O delays incurred as a result of swapin page
faults whose frequency can be affected by the task/process' rss limit.  Hence
swapin delays can act as feedback for rss limit changes independent of I/O
priority changes.

Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:56 -07:00
Luke Yang
22c4af4092 [PATCH] nommu: export two symbols for drivers to use
nommu.c needs to export two more symbols for drivers to use:
remap_pfn_range and unmap_mapping_range.

Signed-off-by: Luke Yang <luke.adi@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:53 -07:00
Anil Keshavamurthy
c38c8db722 [PATCH] ia64: race flushing icache in COW path
There is a race condition that showed up in a threaded JIT environment.
The situation is that a process with a JIT code page forks, so the page is
marked read-only, then some threads are created in the child.  One of the
threads attempts to add a new code block to the JIT page, so a
copy-on-write fault is taken, and the kernel allocates a new page, copies
the data, installs the new pte, and then calls lazy_mmu_prot_update() to
flush caches to make sure that the icache and dcache are in sync.
Unfortunately, the other thread runs right after the new pte is installed,
but before the caches have been flushed.  It tries to execute some old JIT
code that was already in this page, but it sees some garbage in the i-cache
from the previous users of the new physical page.

Fix: we must make the caches consistent before installing the pte.  This is
an ia64 only fix because lazy_mmu_prot_update() is a no-op on all other
architectures.

Signed-off-by: Anil Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:51 -07:00
Jan Kiszka
8757d5fa6b [PATCH] mm: fix oom roll-back of __vmalloc_area_node
__vunmap must not rely on area->nr_pages when picking the release methode
for area->pages.  It may be too small when __vmalloc_area_node failed early
due to lacking memory.  Instead, use a flag in vmstruct to differentiate.

Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:51 -07:00
Ingo Molnar
fc818301a8 [PATCH] revert slab.c locking change
Chandra Seetharaman reported SLAB crashes caused by the slab.c lock
annotation patch.  There is only one chunk of that patch that has a
material effect on the slab logic - this patch undoes that chunk.

This was confirmed to fix the slab problem by Chandra.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-13 15:38:43 -07:00
Arjan van de Ven
f1aaee53f2 [PATCH] lockdep: annotate mm/slab.c
mm/slab.c uses nested locking when dealing with 'off-slab'
caches, in that case it allocates the slab header from the
(on-slab) kmalloc caches. Teach the lock validator about
this by putting all on-slab caches into a separate class.

this patch has no effect on non-lockdep kernels.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-13 12:02:44 -07:00
Ingo Molnar
873623dfab [PATCH] lockdep: undo mm/slab.c annotation
undo existing mm/slab.c lock-validator annotations, in preparation
of a new, less intrusive annotation patch.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-13 12:02:44 -07:00
Heiko Carstens
32dd66fce3 [PATCH] vmstat: export all_vm_events()
Add missing EXPORT_SYMBOL for all_vm_events(). Git commit
f8891e5e1f caused this:

  Building modules, stage 2.
  MODPOST
WARNING: "all_vm_events" [arch/s390/appldata/appldata_mem.ko] undefined!
  CC      arch/s390/appldata/appldata_mem.mod.o

Cc: Christoph Lameter <christoph@lameter.com>
Cc: Gerald Schaefer <geraldsc@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:18 -07:00
Adrian Bunk
b0d85c5c30 [PATCH] mm/mmzone.c: EXPORT_UNUSED_SYMBOL
This patch marks three unused exports as EXPORT_UNUSED_SYMBOL.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
Adrian Bunk
26fc52367a [PATCH] mm/memory.c: EXPORT_UNUSED_SYMBOL
This patch marks an unused export as EXPORT_UNUSED_SYMBOL.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
Adrian Bunk
6d46cc6b9b [PATCH] mm/bootmem.c: EXPORT_UNUSED_SYMBOL
This patch marks an unused export as EXPORT_UNUSED_SYMBOL.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:17 -07:00
Andrew Morton
8f72e4028a [PATCH] fadvise: remove dead comments
Cc: "Michael Kerrisk" <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:14 -07:00
Steven Whitehouse
cf57a30843 Merge branch 'master' 2006-07-05 08:27:42 -04:00
Ingo Molnar
36c8b58689 [PATCH] sched: cleanup, remove task_t, convert to struct task_struct
cleanup: remove task_t and convert all the uses to struct task_struct. I
introduced it for the scheduler anno and it was a mistake.

Conversion was mostly scripted, the result was reviewed and all
secondary whitespace and style impact (if any) was fixed up by hand.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:11 -07:00
Ingo Molnar
2b2d5493e1 [PATCH] lockdep: annotate SLAB code
Teach special (recursive) locking code to the lock validator.  Has no effect
on non-lockdep kernels.

Fix initialize-locks-via-memcpy assumptions.

Effects on non-lockdep kernels: the subclass nesting parameter is passed into
cache_free_alien() and __cache_free(), and turns one internal
kmem_cache_free() call into an open-coded __cache_free() call.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:09 -07:00
Ingo Molnar
f20dc5f7c1 [PATCH] lockdep: annotate mm
Teach special (recursive) locking code to the lock validator.  Has no effect
on non-lockdep kernels.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:07 -07:00
Ingo Molnar
e4d9191885 [PATCH] lockdep: locking init debugging improvement
Locking init improvement:

 - introduce and use __SPIN_LOCK_UNLOCKED for array initializations,
   to pass in the name string of locks, used by debugging

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:02 -07:00
Ingo Molnar
9a11b49a80 [PATCH] lockdep: better lock debugging
Generic lock debugging:

 - generalized lock debugging framework. For example, a bug in one lock
   subsystem turns off debugging in all lock subsystems.

 - got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from
   the mutex/rtmutex debugging code: it caused way too much prototype
   hackery, and lockdep will give the same information anyway.

 - ability to do silent tests

 - check lock freeing in vfree too.

 - more finegrained debugging options, to allow distributions to
   turn off more expensive debugging features.

There's no separate 'held mutexes' list anymore - but there's a 'held locks'
stack within lockdep, which unifies deadlock detection across all lock
classes.  (this is independent of the lockdep validation stuff - lockdep first
checks whether we are holding a lock already)

Here are the current debugging options:

CONFIG_DEBUG_MUTEXES=y
CONFIG_DEBUG_LOCK_ALLOC=y

which do:

 config DEBUG_MUTEXES
          bool "Mutex debugging, basic checks"

 config DEBUG_LOCK_ALLOC
         bool "Detect incorrect freeing of live mutexes"

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:01 -07:00
Christoph Lameter
9614634fe6 [PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/O
It turns out that it is advantageous to leave a small portion of unmapped file
backed pages if all of a zone's pages (or almost all pages) are allocated and
so the page allocator has to go off-node.

This allows recently used file I/O buffers to stay on the node and
reduces the times that zone reclaim is invoked if file I/O occurs
when we run out of memory in a zone.

The problem is that zone reclaim runs too frequently when the page cache is
used for file I/O (read write and therefore unmapped pages!) alone and we have
almost all pages of the zone allocated.  Zone reclaim may remove 32 unmapped
pages.  File I/O will use these pages for the next read/write requests and the
unmapped pages increase.  After the zone has filled up again zone reclaim will
remove it again after only 32 pages.  This cycle is too inefficient and there
are potentially too many zone reclaim cycles.

With the 1% boundary we may still remove all unmapped pages for file I/O in
zone reclaim pass.  However.  it will take a large number of read and writes
to get back to 1% again where we trigger zone reclaim again.

The zone reclaim 2.6.16/17 does not show this behavior because we have a 30
second timeout.

[akpm@osdl.org: rename the /proc file and the variable]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:26:59 -07:00
Steven Whitehouse
0a1340c185 Merge rsync://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	include/linux/kernel.h
2006-07-03 10:25:08 -04:00
Linus Torvalds
22a3e233ca Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  Remove obsolete #include <linux/config.h>
  remove obsolete swsusp_encrypt
  arch/arm26/Kconfig typos
  Documentation/IPMI typos
  Kconfig: Typos in net/sched/Kconfig
  v9fs: do not include linux/version.h
  Documentation/DocBook/mtdnand.tmpl: typo fixes
  typo fixes: specfic -> specific
  typo fixes in Documentation/networking/pktgen.txt
  typo fixes: occuring -> occurring
  typo fixes: infomation -> information
  typo fixes: disadvantadge -> disadvantage
  typo fixes: aquire -> acquire
  typo fixes: mecanism -> mechanism
  typo fixes: bandwith -> bandwidth
  fix a typo in the RTC_CLASS help text
  smb is no longer maintained

Manually merged trivial conflict in arch/um/kernel/vmlinux.lds.S
2006-06-30 15:39:30 -07:00
Christoph Lameter
ed11d9eb22 [PATCH] slab: consolidate code to free slabs from freelist
Post and discussion:
http://marc.theaimsgroup.com/?t=115074342800003&r=1&w=2

Code in __shrink_node() duplicates code in cache_reap()

Add a new function drain_freelist that removes slabs with objects that are
already free and use that in various places.

This eliminates the __node_shrink() function and provides the interrupt
holdoff reduction from slab_free to code that used to call __node_shrink.

[akpm@osdl.org: build fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Christoph Lameter
f8891e5e1f [PATCH] Light weight event counters
The remaining counters in page_state after the zoned VM counter patches
have been applied are all just for show in /proc/vmstat.  They have no
essential function for the VM.

We use a simple increment of per cpu variables.  In order to avoid the most
severe races we disable preempt.  Preempt does not prevent the race between
an increment and an interrupt handler incrementing the same statistics
counter.  However, that race is exceedingly rare, we may only loose one
increment or so and there is no requirement (at least not in kernel) that
the vm event counters have to be accurate.

In the non preempt case this results in a simple increment for each
counter.  For many architectures this will be reduced by the compiler to a
single instruction.  This single instruction is atomic for i386 and x86_64.
 And therefore even the rare race condition in an interrupt is avoided for
both architectures in most cases.

The patchset also adds an off switch for embedded systems that allows a
building of linux kernels without these counters.

The implementation of these counters is through inline code that hopefully
results in only a single instruction increment instruction being emitted
(i386, x86_64) or in the increment being hidden though instruction
concurrency (EPIC architectures such as ia64 can get that done).

Benefits:
- VM event counter operations usually reduce to a single inline instruction
  on i386 and x86_64.
- No interrupt disable, only preempt disable for the preempt case.
  Preempt disable can also be avoided by moving the counter into a spinlock.
- Handling is similar to zoned VM counters.
- Simple and easily extendable.
- Can be omitted to reduce memory use for embedded use.

References:

RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=113512330605497&w=2
RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=114988082814934&w=2
local_t http://marc.theaimsgroup.com/?l=linux-kernel&m=114991748606690&w=2
V2 http://marc.theaimsgroup.com/?t=115014808400007&r=1&w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&m=115024767022346&w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&m=115047968808926&w=2

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Christoph Lameter
ca889e6c45 [PATCH] Use Zoned VM Counters for NUMA statistics
The numa statistics are really event counters.  But they are per node and
so we have had special treatment for these counters through additional
fields on the pcp structure.  We can now use the per zone nature of the
zoned VM counters to realize these.

This will shrink the size of the pcp structure on NUMA systems.  We will
have some room to add additional per zone counters that will all still fit
in the same cacheline.

 Bits	Prior pcp size	  	Size after patch	We can add
 ------------------------------------------------------------------
 64	128 bytes (16 words)	80 bytes (10 words)	48
 32	 76 bytes (19 words)	56 bytes (14 words)	8 (64 byte cacheline)
							72 (128 byte)

Remove the special statistics for numa and replace them with zoned vm
counters.  This has the side effect that global sums of these events now
show up in /proc/vmstat.

Also take the opportunity to move the zone_statistics() function from
page_alloc.c into vmstat.c.

Discussions:
V2 http://marc.theaimsgroup.com/?t=115048227000002&r=1&w=2

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Andrew Morton
bab1846a05 [PATCH] zoned-vm-counters: remove read_page_state()
No callers.

Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Christoph Lameter
c24f21bda8 [PATCH] zoned vm counters: remove useless struct wbs
Remove writeback state

We can remove some functions now that were needed to calculate the page state
for writeback control since these statistics are now directly available.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Christoph Lameter
d2c5e30c9a [PATCH] zoned vm counters: conversion of nr_bounce to per zone counter
Conversion of nr_bounce to a per zone counter

nr_bounce is only used for proc output.  So it could be left as an event
counter.  However, the event counters may not be accurate and nr_bounce is
categorizing types of pages in a zone.  So we really need this to also be a
per zone counter.

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Christoph Lameter
fd39fc8561 [PATCH] zoned vm counters: conversion of nr_unstable to per zone counter
Conversion of nr_unstable to a per zone counter

We need to do some special modifications to the nfs code since there are
multiple cases of disposition and we need to have a page ref for proper
accounting.

This converts the last critical page state of the VM and therefore we need to
remove several functions that were depending on GET_PAGE_STATE_LAST in order
to make the kernel compile again.  We are only left with event type counters
in page state.

[akpm@osdl.org: bugfixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:36 -07:00
Christoph Lameter
ce866b34ae [PATCH] zoned vm counters: conversion of nr_writeback to per zone counter
Conversion of nr_writeback to per zone counter.

This removes the last page_state counter from arch/i386/mm/pgtable.c so we
drop the page_state from there.

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
b1e7a8fd85 [PATCH] zoned vm counters: conversion of nr_dirty to per zone counter
This makes nr_dirty a per zone counter.  Looping over all processors is
avoided during writeback state determination.

The counter aggregation for nr_dirty had to be undone in the NFS layer since
we summed up the page counts from multiple zones.  Someone more familiar with
NFS should probably review what I have done.

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
df849a1529 [PATCH] zoned vm counters: conversion of nr_pagetables to per zone counter
Conversion of nr_page_table_pages to a per zone counter

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
9a865ffa34 [PATCH] zoned vm counters: conversion of nr_slab to per zone counter
- Allows reclaim to access counter without looping over processor counts.

- Allows accurate statistics on how many pages are used in a zone by
  the slab. This may become useful to balance slab allocations over
  various zones.

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
34aa1330f9 [PATCH] zoned vm counters: zone_reclaim: remove /proc/sys/vm/zone_reclaim_interval
The zone_reclaim_interval was necessary because we were not able to determine
how many unmapped pages exist in a zone.  Therefore we had to scan in
intervals to figure out if any pages were unmapped.

With the zoned counters and NR_ANON_PAGES we now know the number of pagecache
pages and the number of mapped pages in a zone.  So we can simply skip the
reclaim if there is an insufficient number of unmapped pages.  We use
SWAP_CLUSTER_MAX as the boundary.

Drop all support for /proc/sys/vm/zone_reclaim_interval.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
f3dbd34460 [PATCH] zoned vm counters: split NR_ANON_PAGES off from NR_FILE_MAPPED
The current NR_FILE_MAPPED is used by zone reclaim and the dirty load
calculation as the number of mapped pagecache pages.  However, that is not
true.  NR_FILE_MAPPED includes the mapped anonymous pages.  This patch
separates those and therefore allows an accurate tracking of the anonymous
pages per zone.

It then becomes possible to determine the number of unmapped pages per zone
and we can avoid scanning for unmapped pages if there are none.

Also it may now be possible to determine the mapped/unmapped ratio in
get_dirty_limit.  Isnt the number of anonymous pages irrelevant in that
calculation?

Note that this will change the meaning of the number of mapped pages reported
in /proc/vmstat /proc/meminfo and in the per node statistics.  This may affect
user space tools that monitor these counters!  NR_FILE_MAPPED works like
NR_FILE_DIRTY.  It is only valid for pagecache pages.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
bf02cf4b6c [PATCH] zoned vm counters: remove NR_FILE_MAPPED from scan control structure
We can now access the number of pages in a mapped state in an inexpensive way
in shrink_active_list.  So drop the nr_mapped field from scan_control.

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:35 -07:00
Christoph Lameter
347ce434d5 [PATCH] zoned vm counters: conversion of nr_pagecache to per zone counter
Currently a single atomic variable is used to establish the size of the page
cache in the whole machine.  The zoned VM counters have the same method of
implementation as the nr_pagecache code but also allow the determination of
the pagecache size per zone.

Remove the special implementation for nr_pagecache and make it a zoned counter
named NR_FILE_PAGES.

Updates of the page cache counters are always performed with interrupts off.
We can therefore use the __ variant here.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:34 -07:00
Christoph Lameter
65ba55f500 [PATCH] zoned vm counters: convert nr_mapped to per zone counter
nr_mapped is important because it allows a determination of how many pages of
a zone are not mapped, which would allow a more efficient means of determining
when we need to reclaim memory in a zone.

We take the nr_mapped field out of the page state structure and define a new
per zone counter named NR_FILE_MAPPED (the anonymous pages will be split off
from NR_MAPPED in the next patch).

We replace the use of nr_mapped in various kernel locations.  This avoids the
looping over all processors in try_to_free_pages(), writeback, reclaim (swap +
zone reclaim).

[akpm@osdl.org: bugfix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:34 -07:00
Christoph Lameter
2244b95a7b [PATCH] zoned vm counters: basic ZVC (zoned vm counter) implementation
Per zone counter infrastructure

The counters that we currently have for the VM are split per processor.  The
processor however has not much to do with the zone these pages belong to.  We
cannot tell f.e.  how many ZONE_DMA pages are dirty.

So we are blind to potentially inbalances in the usage of memory in various
zones.  F.e.  in a NUMA system we cannot tell how many pages are dirty on a
particular node.  If we knew then we could put measures into the VM to balance
the use of memory between different zones and different nodes in a NUMA
system.  For example it would be possible to limit the dirty pages per node so
that fast local memory is kept available even if a process is dirtying huge
amounts of pages.

Another example is zone reclaim.  We do not know how many unmapped pages exist
per zone.  So we just have to try to reclaim.  If it is not working then we
pause and try again later.  It would be better if we knew when it makes sense
to reclaim unmapped pages from a zone.  This patchset allows the determination
of the number of unmapped pages per zone.  We can remove the zone reclaim
interval with the counters introduced here.

Futhermore the ability to have various usage statistics available will allow
the development of new NUMA balancing algorithms that may be able to improve
the decision making in the scheduler of when to move a process to another node
and hopefully will also enable automatic page migration through a user space
program that can analyse the memory load distribution and then rebalance
memory use in order to increase performance.

The counter framework here implements differential counters for each processor
in struct zone.  The differential counters are consolidated when a threshold
is exceeded (like done in the current implementation for nr_pageache), when
slab reaping occurs or when a consolidation function is called.

Consolidation uses atomic operations and accumulates counters per zone in the
zone structure and also globally in the vm_stat array.  VM functions can
access the counts by simply indexing a global or zone specific array.

The arrangement of counters in an array also simplifies processing when output
has to be generated for /proc/*.

Counters can be updated by calling inc/dec_zone_page_state or
_inc/dec_zone_page_state analogous to *_page_state.  The second group of
functions can be called if it is known that interrupts are disabled.

Special optimized increment and decrement functions are provided.  These can
avoid certain checks and use increment or decrement instructions that an
architecture may provide.

We also add a new CONFIG_DMA_IS_NORMAL that signifies that an architecture can
do DMA to all memory and therefore ZONE_NORMAL will not be populated.  This is
only currently set for IA64 SGI SN2 and currently only affects
node_page_state().  In the best case node_page_state can be reduced to
retrieving a single counter for the one zone on the node.

[akpm@osdl.org: cleanups]
[akpm@osdl.org: export vm_stat[] for filesystems]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:34 -07:00
Christoph Lameter
f6ac2354d7 [PATCH] zoned vm counters: create vmstat.c/.h from page_alloc.c/.h
NOTE: ZVC are *not* the lightweight event counters.  ZVCs are reliable whereas
event counters do not need to be.

Zone based VM statistics are necessary to be able to determine what the state
of memory in one zone is.  In a NUMA system this can be helpful for local
reclaim and other memory optimizations that may be able to shift VM load in
order to get more balanced memory use.

It is also useful to know how the computing load affects the memory
allocations on various zones.  This patchset allows the retrieval of that data
from userspace.

The patchset introduces a framework for counters that is a cross between the
existing page_stats --which are simply global counters split per cpu-- and the
approach of deferred incremental updates implemented for nr_pagecache.

Small per cpu 8 bit counters are added to struct zone.  If the counter exceeds
certain thresholds then the counters are accumulated in an array of
atomic_long in the zone and in a global array that sums up all zone values.
The small 8 bit counters are next to the per cpu page pointers and so they
will be in high in the cpu cache when pages are allocated and freed.

Access to VM counter information for a zone and for the whole machine is then
possible by simply indexing an array (Thanks to Nick Piggin for pointing out
that approach).  The access to the total number of pages of various types does
no longer require the summing up of all per cpu counters.

Benefits of this patchset right now:

- Ability for UP and SMP configuration to determine how memory
  is balanced between the DMA, NORMAL and HIGHMEM zones.

- loops over all processors are avoided in writeback and
  reclaim paths. We can avoid caching the writeback information
  because the needed information is directly accessible.

- Special handling for nr_pagecache removed.

- zone_reclaim_interval vanishes since VM stats can now determine
  when it is worth to do local reclaim.

- Fast inline per node page state determination.

- Accurate counters in /sys/devices/system/node/node*/meminfo. Current
  counters are counting simply which processor allocated a page somewhere
  and guestimate based on that. So the counters were not useful to show
  the actual distribution of page use on a specific zone.

- The swap_prefetch patch requires per node statistics in order to
  figure out when processors of a node can prefetch. This patch provides
  some of the needed numbers.

- Detailed VM counters available in more /proc and /sys status files.

References to earlier discussions:
V1 http://marc.theaimsgroup.com/?l=linux-kernel&m=113511649910826&w=2
V2 http://marc.theaimsgroup.com/?l=linux-kernel&m=114980851924230&w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&m=115014697910351&w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&m=115024767318740&w=2

Performance tests with AIM7 did not show any regressions.  Seems to be a tad
faster even.  Tested on ia64/NUMA.  Builds fine on i386, SMP / UP.  Includes
fixes for s390/arm/uml arch code.

This patch:

Move counter code from page_alloc.c/page-flags.h to vmstat.c/h.

Create vmstat.c/vmstat.h by separating the counter code and the proc
functions.

Move the vm_stat_text array before zoneinfo_show.

[akpm@osdl.org: s390 build fix]
[akpm@osdl.org: HOTPLUG_CPU build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30 11:25:34 -07:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Linus Torvalds
602cada851 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6: (22 commits)
  [PATCH] devfs: Remove it from the feature_removal.txt file
  [PATCH] devfs: Last little devfs cleanups throughout the kernel tree.
  [PATCH] devfs: Rename TTY_DRIVER_NO_DEVFS to TTY_DRIVER_DYNAMIC_DEV
  [PATCH] devfs: Remove the tty_driver devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the line_driver devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the videodevice devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed
  [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
  [PATCH] devfs: Remove devfs_remove() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_bdev() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_symlink() function from the kernel tree
  [PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
  [PATCH] devfs: Remove devfs_*_tape() functions from the kernel tree
  [PATCH] devfs: Remove devfs support from the sound subsystem
  [PATCH] devfs: Remove devfs support from the ide subsystem.
  [PATCH] devfs: Remove devfs support from the serial subsystem
  [PATCH] devfs: Remove devfs from the init code
  [PATCH] devfs: Remove devfs from the partition code
  ...
2006-06-29 14:19:21 -07:00
Linus Torvalds
1903ac54f8 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6:
  [PATCH] i386: export memory more than 4G through /proc/iomem
  [PATCH] 64bit Resource: finally enable 64bit resource sizes
  [PATCH] 64bit Resource: convert a few remaining drivers to use resource_size_t where needed
  [PATCH] 64bit resource: change pnp core to use resource_size_t
  [PATCH] 64bit resource: change pci core and arch code to use resource_size_t
  [PATCH] 64bit resource: change resource core to use resource_size_t
  [PATCH] 64bit resource: introduce resource_size_t for the start and end of struct resource
  [PATCH] 64bit resource: fix up printks for resources in misc drivers
  [PATCH] 64bit resource: fix up printks for resources in arch and core code
  [PATCH] 64bit resource: fix up printks for resources in pcmcia drivers
  [PATCH] 64bit resource: fix up printks for resources in video drivers
  [PATCH] 64bit resource: fix up printks for resources in ide drivers
  [PATCH] 64bit resource: fix up printks for resources in mtd drivers
  [PATCH] 64bit resource: fix up printks for resources in pci core and hotplug drivers
  [PATCH] 64bit resource: fix up printks for resources in networks drivers
  [PATCH] 64bit resource: fix up printks for resources in sound drivers
  [PATCH] 64bit resource: C99 changes for struct resource declarations

Fixed up trivial conflict in drivers/ide/pci/cmd64x.c (the printk that
was changed by the 64-bit resources had been deleted in the meantime ;)
2006-06-29 10:49:17 -07:00
Yasunori Goto
cc57637b0b [PATCH] solve config broken: undefined reference to `online_page'
Memory hotplug code of i386 adds memory to only highmem.  So, if
CONFIG_HIGHMEM is not set, CONFIG_MEMORY_HOTPLUG shouldn't be set.
Otherwise, it causes compile error.

In addition, many architecture can't use memory hotplug feature yet.  So, I
introduce CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:20 -07:00
Andrew Morton
81b0c87133 [PATCH] generic_file_buffered_write(): handle zero-length iovec segments
The recent generic_file_write() deadlock fix caused
generic_file_buffered_write() to loop inifinitely when presented with a
zero-length iovec segment.  Fix.

Note that this fix deliberately avoids calling ->prepare_write(),
->commit_write() etc with a zero-length write.  This is because I don't trust
all filesystems to get that right.

This is a cautious approach, for 2.6.17.x.  For 2.6.18 we should just go ahead
and call ->prepare_write() and ->commit_write() with the zero length and fix
any broken filesystems.  So I'll make that change once this code is stabilised
and backported into 2.6.17.x.

The reason for preferring to call ->prepare_write() and ->commit_write() with
the zero-length segment: a zero-length segment _should_ be sufficiently
uncommon that this is the correct way of handling it.  We don't want to
optimise for poorly-written userspace at the expense of well-written
userspace.

Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Greg KH <greg@kroah.com>
Cc: <stable@kernel.org>
Cc: walt <wa1ter@myrealbox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:20 -07:00
Christoph Hellwig
f5e54d6e53 [PATCH] mark address_space_operations const
Same as with already do with the file operations: keep them in .rodata and
prevents people from doing runtime patching.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28 14:59:04 -07:00
Ingo Molnar
e7eebaf6a8 [PATCH] pi-futex: rt mutex debug
Runtime debugging functionality for rt-mutexes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:47 -07:00
Ingo Molnar
f9b8404cf8 [PATCH] pi-futex: introduce debug_check_no_locks_freed()
Add debug_check_no_locks_freed(), as a central inline to add
bad-lock-free-debugging functionality to.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:46 -07:00
Chandra Seetharaman
26c2143b63 [PATCH] cpu hotplug: make cpu_notifier related notifier calls __cpuinit only
Make notifier_calls associated with cpu_notifier as __cpuinit.

__cpuinit makes sure that the function is init time only unless
CONFIG_HOTPLUG_CPU is defined.

[akpm@osdl.org: section fix]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:41 -07:00
Chandra Seetharaman
74b85f3790 [PATCH] cpu hotplug: make cpu_notifier related notifier blocks __cpuinit only
Make notifier_blocks associated with cpu_notifier as __cpuinitdata.

__cpuinitdata makes sure that the data is init time only unless
CONFIG_HOTPLUG_CPU is defined.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:41 -07:00
Chandra Seetharaman
9c7b216d23 [PATCH] cpu hotplug: revert init patch submitted for 2.6.17
In 2.6.17, there was a problem with cpu_notifiers and XFS.  I provided a
band-aid solution to solve that problem.  In the process, i undid all the
changes you both were making to ensure that these notifiers were available
only at init time (unless CONFIG_HOTPLUG_CPU is defined).

We deferred the real fix to 2.6.18.  Here is a set of patches that fixes the
XFS problem cleanly and makes the cpu notifiers available only at init time
(unless CONFIG_HOTPLUG_CPU is defined).

If CONFIG_HOTPLUG_CPU is defined then cpu notifiers are available at run
time.

This patch reverts the notifier_call changes made in 2.6.17

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:40 -07:00
Vladimir V. Saveliev
6527c2bdf1 [PATCH] generic_file_buffered_write(): deadlock on vectored write
generic_file_buffered_write() prefaults in user pages in order to avoid
deadlock on copying from the same page as write goes to.

However, it looks like there is a problem when write is vectored:
fault_in_pages_readable brings in current segment or its part (maxlen).
OTOH, filemap_copy_from_user_iovec is called to copy number of bytes
(bytes) which may exceed current segment, so filemap_copy_from_user_iovec
switches to the next segment which is not brought in yet.  Pagefault is
generated.  That causes the deadlock if pagefault is for the same page
write goes to: page being written is locked and not uptodate, pagefault
will deadlock trying to lock locked page.

[akpm@osdl.org: somewhat rewritten]
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:39 -07:00
Ingo Molnar
34af946a22 [PATCH] spin/rwlock init cleanups
locking init cleanups:

 - convert " = SPIN_LOCK_UNLOCKED" to spin_lock_init() or DEFINE_SPINLOCK()
 - convert rwlocks in a similar manner

this patch was generated automatically.

Motivation:

 - cleanliness
 - lockdep needs control of lock initialization, which the open-coded
   variants do not give
 - it's also useful for -rt and for lock debugging in general

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:39 -07:00
Randy Dunlap
c9cf55285e [PATCH] add poison.h and patch primary users
Localize poison values into one header file for better documentation and
easier/quicker debugging and so that the same values won't be used for
multiple purposes.

Use these constants in core arch., mm, driver, and fs code.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Matt Mackall <mpm@selenic.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:38 -07:00
Yasunori Goto
0fc44159bf [PATCH] Register sysfs file for hotplugged new node
When new node becomes enable by hot-add, new sysfs file must be created for
new node.  So, if new node is enabled by add_memory(), register_one_node() is
called to create it.  In addition, I386's arch_register_node() and a part of
register_nodes() of powerpc are consolidated to register_one_node() as a
generic_code().

This is tested by Tiger4(IPF) with node hot-plug emulation.

Signed-off-by: Keiichiro Tokunaga <tokuanga.keiich@jp.fujitsu.com>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:36 -07:00
Yasunori Goto
1f04bbd2d3 [PATCH] sparc64: support sparsemem and !memory hotplug
Fix "undefined reference to `arch_add_memory'" on sparc64 allmodconfig.

sparc64 doesn't support memory hotplug.  But we want it to support
sparsemem.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:36 -07:00
KAMEZAWA Hiroyuki
2842f11419 [PATCH] catch valid mem range at onlining memory
This patch allows hot-add memory which is not aligned to section.

Now, hot-added memory has to be aligned to section size.  Considering big
section sized archs, this is not useful.

When hot-added memory is registerd as iomem resoruce by iomem resource
patch, we can make use of that information to detect valid memory range.

Note: With this, not-aligned memory can be registerd. To allow hot-add
      memory with holes, we have to do more work around add_memory().
      (It doesn't allows add memory to already existing mem section.)

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:36 -07:00
KAMEZAWA Hiroyuki
0a54703904 [PATCH] register hot-added memory to iomem resource
Register hot-added memory to iomem_resource.  With this, /proc/iomem can
show hot-added memory.

Note: kdump uses /proc/iomem to catch memory range when it is installed.
      So, kdump should be re-installed after /proc/iomem change.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:36 -07:00
Yasunori Goto
9af3c2dea3 [PATCH] pgdat allocation for new node add (call pgdat allocation)
Add node-hot-add support to add_memory().

node hotadd uses this sequence.
1. allocate pgdat.
2. refresh NODE_DATA()
3. call free_area_init_node() to initialize
4. create sysfs entry
5. add memory (old add_memory())
6. set node online
7. run kswapd for new node.
(8). update zonelist after pages are onlined. (This is already merged in -mm
   due to update phase is difference.)

Note:
  To make common function as much as possible,
  there is 2 changes from v2.
    - The old add_memory(), which is defiend by each archs,
      is renamed to arch_add_memory(). New add_memory becomes
      caller of arch dependent function as a common code.

    - This patch changes add_memory()'s interface
        From: add_memory(start, end)
        TO  : add_memory(nid, start, end).
      It was cause of similar code that finding node id from
      physical address is inside of old add_memory() on each arch.

      In addition, acpi memory hotplug driver can find node id easier.
      In v2, it must walk DSDT'S _CRS by matching physical address to
      get the handle of its memory device, then get _PXM and node id.
      Because input is just physical address.
      However, in v3, the acpi driver can use handle to get _PXM and node id
      for the new memory device. It can pass just node id to add_memory().

Fix interface of arch_add_memory() is in next patche.

Signed-off-by: Yasunori Goto     <y-goto@jp.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:36 -07:00
Yasunori Goto
3218ae14b1 [PATCH] pgdat allocation for new node add (export kswapd start func)
When node is hot-added, kswapd for the node should start.  This export kswapd
start function as kswapd_run() to use at add_memory().

[akpm@osdl.org: daemonize() isn't needed when using the kthread API]
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:36 -07:00
Yasunori Goto
bc02af93dd [PATCH] pgdat allocation for new node add (specify node id)
Change the name of old add_memory() to arch_add_memory.  And use node id to
get pgdat for the node at NODE_DATA().

Note: Powerpc's old add_memory() is defined as __devinit. However,
      add_memory() is usually called only after bootup.
      I suppose it may be redundant. But, I'm not well known about powerpc.
      So, I keep it. (But, __meminit is better at least.)

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:35 -07:00
Greg Kroah-Hartman
6550e07f41 [PATCH] 64bit Resource: finally enable 64bit resource sizes
Introduce the Kconfig entry and actually switch to a 64bit value, if
wanted, for resource_size_t.

Based on a patch series originally from Vivek Goyal <vgoyal@in.ibm.com>

Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-27 09:24:00 -07:00
Linus Torvalds
da206c9e68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
  typo fixes
  Clean up 'inline is not at beginning' warnings for usb storage
  Storage class should be first
  i386: Trivial typo fixes
  ixj: make ixj_set_tone_off() static
  spelling fixes
  fix paniced->panicked typos
  Spelling fixes for Documentation/atomic_ops.txt
  move acknowledgment for Mark Adler to CREDITS
  remove the bouncing email address of David Campbell
2006-06-26 13:33:14 -07:00
Greg Kroah-Hartman
ff23eca3e8 [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
Also fixes up all files that #include it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:08 -07:00
Greg Kroah-Hartman
95dc112a57 [PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
Removes the devfs_mk_dir() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:06 -07:00
Eric W. Biederman
99f8955183 [PATCH] proc: don't lock task_structs indefinitely
Every inode in /proc holds a reference to a struct task_struct.  If a
directory or file is opened and remains open after the the task exits this
pinning continues.  With 8K stacks on a 32bit machine the amount pinned per
file descriptor is about 10K.

Normally I would figure a reasonable per user process limit is about 100
processes.  With 80 processes, with a 1000 file descriptors each I can trigger
the 00M killer on a 32bit kernel, because I have pinned about 800MB of useless
data.

This patch replaces the struct task_struct pointer with a pointer to a struct
task_ref which has a struct task_struct pointer.  The so the pinning of dead
tasks does not happen.

The code now has to contend with the fact that the task may now exit at any
time.  Which is a little but not muh more complicated.

With this change it takes about 1000 processes each opening up 1000 file
descriptors before I can trigger the OOM killer.  Much better.

[mlp@google.com: task_mmu small fixes]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Paul Jackson <pj@sgi.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Albert Cahalan <acahalan@gmail.com>
Signed-off-by: Prasanna Meda <mlp@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:25 -07:00
Akinobu Mita
1bfba4e8ea [PATCH] core: use list_move()
This patch converts the combination of list_del(A) and list_add(A, B) to
list_move(A, B).

Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:17 -07:00
Andreas Mohr
d6e05edc59 spelling fixes
acquired (aquired)
contiguous (contigious)
successful (succesful, succesfull)
surprise (suprise)
whether (weather)
some other misspellings

Signed-off-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-26 18:35:02 +02:00
Linus Torvalds
1d77062b14 Merge git://git.linux-nfs.org/pub/linux/nfs-2.6
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (51 commits)
  nfs: remove nfs_put_link()
  nfs-build-fix-99
  git-nfs-build-fixes
  Merge branch 'odirect'
  NFS: alloc nfs_read/write_data as direct I/O is scheduled
  NFS: Eliminate nfs_get_user_pages()
  NFS: refactor nfs_direct_free_user_pages
  NFS: remove user_addr, user_count, and pos from nfs_direct_req
  NFS: "open code" the NFS direct write rescheduler
  NFS: Separate functions for counting outstanding NFS direct I/Os
  NLM: Fix reclaim races
  NLM: sem to mutex conversion
  locks.c: add the fl_owner to nlm_compare_locks
  NFS: Display the chosen RPCSEC_GSS security flavour in /proc/mounts
  NFS: Split fs/nfs/inode.c
  NFS: Fix typo in nfs_do_clone_mount()
  NFS: Fix compile errors introduced by referrals patches
  NFSv4: Ensure that referral mounts bind to a reserved port
  NFSv4: A root pathname is sent as a zero component4
  NFSv4: Follow a referral
  ...
2006-06-25 10:54:14 -07:00
Wu Fengguang
76d42bd969 [PATCH] readahead: backoff on I/O error
Backoff readahead size exponentially on I/O error.

Michael Tokarev <mjt@tls.msk.ru> described the problem as:

[QUOTE]
Suppose there's a CD-rom with a scratch/etc, one sector is unreadable.
In order to "fix" it, one have to read it and write to another CD-rom,
or something.. or just ignore the error (if it's just a skip in a video
stream).  Let's assume the unreadable block is number U.

But current behavior is just insane.  An application requests block
number N, which is before U. Kernel tries to read-ahead blocks N..U.
Cdrom drive tries to read it, re-read it.. for some time.  Finally,
when all the N..U-1 blocks are read, kernel returns block number N
(as requested) to an application, successefully.

Now an app requests block number N+1, and kernel tries to read
blocks N+1..U+1.  Retrying again as in previous step.

And so on, up to when an app requests block number U-1.  And when,
finally, it requests block U, it receives read error.

So, kernel currentry tries to re-read the same failing block as
many times as the current readahead value (256 (times?) by default).

This whole process already killed my cdrom drive (I posted about it
to LKML several months ago) - literally, the drive has fried, and
does not work anymore.  Ofcourse that problem was a bug in firmware
(or whatever) of the drive *too*, but.. main problem with that is
current readahead logic as described above.
[/QUOTE]

Which was confirmed by Jens Axboe <axboe@suse.de>:

[QUOTE]
For ide-cd, it tends do only end the first part of the request on a
medium error. So you may see a lot of repeats :/
[/QUOTE]

With this patch, retries are expected to be reduced from, say, 256, to 5.

[akpm@osdl.org: cleanups]
Signed-off-by: Wu Fengguang <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:01:17 -07:00
Randy Dunlap
bd40cddae2 [PATCH] kernel-doc: mm/readhead fixup
Put short function description for read_cache_pages() on one line as needed
by kernel-doc.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:01:10 -07:00
NeilBrown
01408c4939 [PATCH] Prepare for __copy_from_user_inatomic to not zero missed bytes
The problem is that when we write to a file, the copy from userspace to
pagecache is first done with preemption disabled, so if the source address is
not immediately available the copy fails *and* *zeros* *the* *destination*.

This is a problem because a concurrent read (which admittedly is an odd thing
to do) might see zeros rather that was there before the write, or what was
there after, or some mixture of the two (any of these being a reasonable thing
to see).

If the copy did fail, it will immediately be retried with preemption
re-enabled so any transient problem with accessing the source won't cause an
error.

The first copying does not need to zero any uncopied bytes, and doing so
causes the problem.  It uses copy_from_user_atomic rather than copy_from_user
so the simple expedient is to change copy_from_user_atomic to *not* zero out
bytes on failure.

The first of these two patches prepares for the change by fixing two places
which assume copy_from_user_atomic does zero the tail.  The two usages are
very similar pieces of code which copy from a userspace iovec into one or more
page-cache pages.  These are changed to remove the assumption.

The second patch changes __copy_from_user_inatomic* to not zero the tail.
Once these are accepted, I will look at similar patches of other architectures
where this is important (ppc, mips and sparc being the ones I can find).

This patch:

There is a problem with __copy_from_user_inatomic zeroing the tail of the
buffer in the case of an error.  As it is called in atomic context, the error
may be transient, so it results in zeros being written where maybe they
shouldn't be.

In the usage in filemap, this opens a window for a well timed read to see data
(zeros) which is not consistent with any ordering of reads and writes.

Most cases where __copy_from_user_inatomic is called, a failure results in
__copy_from_user being called immediately.  As long as the latter zeros the
tail, the former doesn't need to.  However in *copy_from_user_iovec
implementations (in both filemap and ntfs/file), it is assumed that
copy_from_user_inatomic will zero the tail.

This patch removes that assumption, so that after this patch it will
be safe for copy_from_user_inatomic to not zero the tail.

This patch also adds some commentary to filemap.h and asm-i386/uaccess.h.

After this patch, all architectures that might disable preempt when
kmap_atomic is called need to have their __copy_from_user_inatomic* "fixed".
This includes
 - powerpc
 - i386
 - mips
 - sparc

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:01:09 -07:00
Chris Wright
43b0bc00fd [PATCH] cpuset: remove extra cpuset_zone_allowed check in __alloc_pages
This is redundant with check in wakeup_kswapd.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Paul Jackson <pj@sgi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:01:08 -07:00
Andrew Morton
d616e09ab3 [PATCH] pdflush: handle resume wakeups
pdflush is carefully designed to ensure that all wakeups have some
corresponding work to do - if a woken-up pdflush thread discovers that it
hasn't been given any work to do then this is considered an error.

That all broke when swsusp came along - because a timer-delivered wakeup to a
frozen pdflush thread will just get lost.  This causes the pdflush thread to
get lost as well: the writeback timer is supposed to be re-armed by pdflush in
process context, but pdflush doesn't execute the callout which does this.

Fix that up by ignoring the return value from try_to_freeze(): jsut proceed,
see if we have any work pending and only go back to sleep if that is not the
case.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:01:06 -07:00
Christoph Lameter
e6a1530d69 [PATCH] Allow migration of mlocked pages
Hugh clarified the role of VM_LOCKED.  So we can now implement page
migration for mlocked pages.

Allow the migration of mlocked pages.  This means that try_to_unmap must
unmap mlocked pages in the migration case.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:00:55 -07:00
Christoph Lameter
7b2259b3e5 [PATCH] page migration: Support a vma migration function
Hooks for calling vma specific migration functions

With this patch a vma may define a vma->vm_ops->migrate function.  That
function may perform page migration on its own (some vmas may not contain page
structs and therefore cannot be handled by regular page migration.  Pages in a
vma may require special preparatory treatment before migration is possible
etc) .  Only mmap_sem is held when the migration function is called.  The
migrate() function gets passed two sets of nodemasks describing the source and
the target of the migration.  The flags parameter either contains

MPOL_MF_MOVE	which means that only pages used exclusively by
		the specified mm should be moved

or

MPOL_MF_MOVE_ALL which means that pages shared with other processes
		should also be moved.

The migration function returns 0 on success or an error condition.  An error
condition will prevent regular page migration from occurring.

On its own this patch cannot be included since there are no users for this
functionality.  But it seems that the uncached allocator will need this
functionality at some point.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:00:55 -07:00
Zach Brown
9f1a3cfcff [PATCH] AOP_TRUNCATED_PAGE victims in read_pages() belong in the LRU
AOP_TRUNCATED_PAGE victims in read_pages() belong in the LRU

Nick Piggin rightly pointed out that the introduction of AOP_TRUNCATED_PAGE
to read_pages() was wrong to leave A_T_P victim pages in the page cache but
not put them in the LRU.  Failing to do so hid them from the VM.

A_T_P just means that the aop method unlocked the page rather than
performing IO.  It would be very rare that the page was truncated between
the unlock and testing A_T_P.  So we leave the pages in the LRU for likely
reuse soon rather than backing them back out of the page cache.  We do this
by matching the behaviour before the A_T_P introduction which added pages
to the LRU regardless of what ->readpage() did.

This doesn't include the unrelated cleanup in Nick's initial fix which
changed read_pages() to return void to match its only caller's behaviour of
ignoring errors.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:00:54 -07:00
Trond Myklebust
816724e65c Merge branch 'master' of /home/trondmy/kernel/linux-2.6/
Conflicts:

	fs/nfs/inode.c
	fs/super.c

Fix conflicts between patch 'NFS: Split fs/nfs/inode.c' and patch
'VFS: Permit filesystem to override root dentry on mount'
2006-06-24 13:07:53 -04:00
Jens Axboe
b31dc66a54 [PATCH] Kill PF_SYNCWRITE flag
A process flag to indicate whether we are doing sync io is incredibly
ugly. It also causes performance problems when one does a lot of async
io and then proceeds to sync it. Part of the io will go out as async,
and the other part as sync. This causes a disconnect between the
previously submitted io and the synced io. For io schedulers such as CFQ,
this will cause us lost merges and suboptimal behaviour in scheduling.

Remove PF_SYNCWRITE completely from the fsync/msync paths, and let
the O_DIRECT path just directly indicate that the writes are sync
by using WRITE_SYNC instead.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-06-23 17:10:39 +02:00
Eric Sesterhenn
125e18745f [PATCH] More BUG_ON conversion
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Acked-by: "Salyzyn, Mark" <mark_salyzyn@adaptec.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:08 -07:00
NeilBrown
e0f23603fb [PATCH] Remove semi-softlockup from invalidate_mapping_pages
If invalidate_mapping_pages is called to invalidate a very large mapping
(e.g.  a very large block device) and if the only active page in that
device is near the end (or at least, at a very large index), such as, say,
the superblock of an md array, and if that page happens to be locked when
invalidate_mapping_pages is called, then

  pagevec_lookup will return this page and
  as it is locked, 'next' will be incremented and pagevec_lookup
  will be called again. and again. and again.
  while we count from 0 upto a very large number.

We should really always set 'next' to 'page->index+1' before going around
the loop again, not just if the page isn't locked.

Cc: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:07 -07:00
Ravikiran G Thirumalai
3cbc564024 [PATCH] percpu_counters: create lib/percpu_counter.c
- Move percpu_counter routines from mm/swap.c to lib/percpu_counter.c

Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:06 -07:00
Pekka Enberg
090d2b185d [PATCH] read_mapping_page for address space
Add read_mapping_page() which is used for callers that pass
mapping->a_ops->readpage as the filler for read_cache_page.  This removes
some duplication from filesystem code.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:02 -07:00
Hiro Yoshioka
c22ce143d1 [PATCH] x86: cache pollution aware __copy_from_user_ll()
Use the x86 cache-bypassing copy instructions for copy_from_user().

Some performance data are

Total of GLOBAL_POWER_EVENTS (CPU cycle samples)

2.6.12.4.orig    1921587
2.6.12.4.nt      1599424
1599424/1921587=83.23% (16.77% reduction)

BSQ_CACHE_REFERENCE (L3 cache miss)
2.6.12.4.orig      57427
2.6.12.4.nt        20858
20858/57427=36.32% (63.7% reduction)

L3 cache miss reduction of __copy_from_user_ll
samples  %
37408    65.1412  vmlinux                  __copy_from_user_ll
23        0.1103  vmlinux                  __copy_user_zeroing_intel_nocache
23/37408=0.061% (99.94% reduction)

Top 5 of 2.6.12.4.nt
Counted GLOBAL_POWER_EVENTS events (time during which processor is not stopped) with a unit mask of 0x01 (mandatory) count 100000
samples  %        app name                 symbol name
128392    8.0274  vmlinux                  __copy_user_zeroing_intel_nocache
64206     4.0143  vmlinux                  journal_add_journal_head
59746     3.7355  vmlinux                  do_get_write_access
47674     2.9807  vmlinux                  journal_put_journal_head
46021     2.8774  vmlinux                  journal_dirty_metadata
pattern9-0-cpu4-0-09011728/summary.out

Counted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x3f (multiple flags) count 3000
samples  %        app name                 symbol name
69755     4.2861  vmlinux                  __copy_user_zeroing_intel_nocache
55685     3.4215  vmlinux                  journal_add_journal_head
52371     3.2179  vmlinux                  __find_get_block
45504     2.7960  vmlinux                  journal_put_journal_head
36005     2.2123  vmlinux                  journal_stop
pattern9-0-cpu4-0-09011744/summary.out

Counted BSQ_CACHE_REFERENCE events (cache references seen by the bus unit) with a unit mask of 0x200 (read 3rd level cache miss) count 3000
samples  %        app name                 symbol name
1147      5.4994  vmlinux                  journal_add_journal_head
881       4.2240  vmlinux                  journal_dirty_data
872       4.1809  vmlinux                  blk_rq_map_sg
734       3.5192  vmlinux                  journal_commit_transaction
617       2.9582  vmlinux                  radix_tree_delete
pattern9-0-cpu4-0-09011731/summary.out

iozone results are

original 2.6.12.4 CPU time = 207.768 sec
cache aware       CPU time = 184.783 sec
(three times run)
184.783/207.768=88.94% (11.06% reduction)

original:
pattern9-0-cpu4-0-08191720/iozone.out:  CPU Utilization: Wall time   45.997    CPU time   64.527    CPU utilization 140.28 %
pattern9-0-cpu4-0-08191741/iozone.out:  CPU Utilization: Wall time   46.878    CPU time   71.933    CPU utilization 153.45 %
pattern9-0-cpu4-0-08191743/iozone.out:  CPU Utilization: Wall time   45.152    CPU time   71.308    CPU utilization 157.93 %

cache awre:
pattern9-0-cpu4-0-09011728/iozone.out:  CPU Utilization: Wall time   44.842    CPU time   62.465    CPU utilization 139.30 %
pattern9-0-cpu4-0-09011731/iozone.out:  CPU Utilization: Wall time   44.718    CPU time   59.273    CPU utilization 132.55 %
pattern9-0-cpu4-0-09011744/iozone.out:  CPU Utilization: Wall time   44.367    CPU time   63.045    CPU utilization 142.10 %

Signed-off-by: Hiro Yoshioka <hyoshiok@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:56 -07:00
David Quigley
86c3a7645c [PATCH] SELinux: add security_task_movememory calls to mm code
This patch inserts security_task_movememory hook calls into memory management
code to enable security modules to mediate this operation between tasks.

Since the last posting, the hook has been renamed following feedback from
Christoph Lameter.

Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Andi Kleen <ak@muc.de>
Acked-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:54 -07:00
Christoph Lameter
742755a1d8 [PATCH] page migration: sys_move_pages(): support moving of individual pages
move_pages() is used to move individual pages of a process. The function can
be used to determine the location of pages and to move them onto the desired
node. move_pages() returns status information for each page.

long move_pages(pid, number_of_pages_to_move,
		addresses_of_pages[],
		nodes[] or NULL,
		status[],
		flags);

The addresses of pages is an array of void * pointing to the
pages to be moved.

The nodes array contains the node numbers that the pages should be moved
to. If a NULL is passed instead of an array then no pages are moved but
the status array is updated. The status request may be used to determine
the page state before issuing another move_pages() to move pages.

The status array will contain the state of all individual page migration
attempts when the function terminates. The status array is only valid if
move_pages() completed successfullly.

Possible page states in status[]:

0..MAX_NUMNODES	The page is now on the indicated node.

-ENOENT		Page is not present

-EACCES		Page is mapped by multiple processes and can only
		be moved if MPOL_MF_MOVE_ALL is specified.

-EPERM		The page has been mlocked by a process/driver and
		cannot be moved.

-EBUSY		Page is busy and cannot be moved. Try again later.

-EFAULT		Invalid address (no VMA or zero page).

-ENOMEM		Unable to allocate memory on target node.

-EIO		Unable to write back page. The page must be written
		back in order to move it since the page is dirty and the
		filesystem does not provide a migration function that
		would allow the moving of dirty pages.

-EINVAL		A dirty page cannot be moved. The filesystem does not provide
		a migration function and has no ability to write back pages.

The flags parameter indicates what types of pages to move:

MPOL_MF_MOVE	Move pages that are only mapped by the process.

MPOL_MF_MOVE_ALL Also move pages that are mapped by multiple processes.
		Requires sufficient capabilities.

Possible return codes from move_pages()

-ENOENT		No pages found that would require moving. All pages
		are either already on the target node, not present, had an
		invalid address or could not be moved because they were
		mapped by multiple processes.

-EINVAL		Flags other than MPOL_MF_MOVE(_ALL) specified or an attempt
		to migrate pages in a kernel thread.

-EPERM		MPOL_MF_MOVE_ALL specified without sufficient priviledges.
		or an attempt to move a process belonging to another user.

-EACCES		One of the target nodes is not allowed by the current cpuset.

-ENODEV		One of the target nodes is not online.

-ESRCH		Process does not exist.

-E2BIG		Too many pages to move.

-ENOMEM		Not enough memory to allocate control array.

-EFAULT		Parameters could not be accessed.

A test program for move_pages() may be found with the patches
on ftp.kernel.org:/pub/linux/kernel/people/christoph/pmig/patches-2.6.17-rc4-mm3

From: Christoph Lameter <clameter@sgi.com>

  Detailed results for sys_move_pages()

  Pass a pointer to an integer to get_new_page() that may be used to
  indicate where the completion status of a migration operation should be
  placed.  This allows sys_move_pags() to report back exactly what happened to
  each page.

  Wish there would be a better way to do this. Looks a bit hacky.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
95a402c384 [PATCH] page migration: use allocator function for migrate_pages()
Instead of passing a list of new pages, pass a function to allocate a new
page.  This allows the correct placement of MPOL_INTERLEAVE pages during page
migration.  It also further simplifies the callers of migrate pages.
migrate_pages() becomes similar to migrate_pages_to() so drop
migrate_pages_to().  The batching of new page allocations becomes unnecessary.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
aaa994b300 [PATCH] page migration: handle freeing of pages in migrate_pages()
Do not leave pages on the lists passed to migrate_pages().  Seems that we will
not need any postprocessing of pages.  This will simplify the handling of
pages by the callers of migrate_pages().

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:53 -07:00
Christoph Lameter
e24f0b8f76 [PATCH] page migration: simplify migrate_pages()
Currently migrate_pages() is mess with lots of goto.  Extract two functions
from migrate_pages() and get rid of the gotos.

Plus we can just unconditionally set the locked bit on the new page since we
are the only one holding a reference.  Locking is to stop others from
accessing the page once we establish references to the new page.

Remove the list_del from move_to_lru in order to have finer control over list
processing.

[akpm@osdl.org: add debug check]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Kirill Korotaev
8f9de51a4a [PATCH] printk() should not be called under zone->lock
This patch fixes printk() under zone->lock in show_free_areas().  It can be
unsafe to call printk() under this lock, since caller can try to
allocate/free some memory and selfdeadlock on this lock.  I found
allocations/freeing mem both in netconsole and serial console.

This issue was faced in reallity when meminfo was periodically printed for
debug purposes and netconsole was used.

Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Randy Dunlap
485bb99b49 [PATCH] kernel-doc for mm/filemap.c
mm/filemap.c:
- add lots of kernel-doc;
- fix some typos and kernel-doc errors;
- drop some blank lines between function close and EXPORT_SYMBOL();

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Paul Drynoff
800590f523 [PATCH] slab: kmalloc, kzalloc comments cleanup and fix
- Move comments for kmalloc to right place, currently it near __do_kmalloc

- Comments for kzalloc

- More detailed comments for kmalloc

- Appearance of "kmalloc" and "kzalloc" man pages after "make mandocs"

[rdunlap@xenotime.net: simplification]
Signed-off-by: Paul Drynoff <pauldrynoff@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
KAMEZAWA Hiroyuki
5a4d436159 [PATCH] update vm_total_pages at memory hotadd
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Andrew Morton
bd1e22b8e0 [PATCH] initialise total_memory() earlier
Initialise total_memory earlier in boot.  Because if for some reason we run
page reclaim early in boot, we don't want total_memory to be zero when we use
it as a divisor.

And rename total_memory to vm_total_pages to avoid naming clashes with
architectures.

Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Martin Bligh <mbligh@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Ingo Molnar
e0a4272679 [PATCH] mm/slab.c: fix early init assumption
The SLAB bootstrap code assumes that the first two kmalloc caches created
(the INDEX_AC and INDEX_L3 kmalloc caches) wont be off-slab.  But due to AC
and L3 structure size increase in lockdep, one of them ended up being
off-slab, and subsequently crashing with:

Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
 [<ffffffff80267478>] kmem_cache_alloc+0x26/0x7d

The fix is to introduce a bootstrap flag and to use it to prevent off-slab
caches being created so early during bootup.

(The calculation for off-slab caches is quite complex so i didnt want to
complicate things with introducing yet another INDEX_ calculation, the flag
approach is simpler and smaller.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Hugh Dickins
668e0d8f1a [PATCH] fix update_mmu_cache in fremap.c
There are two calls to update_mmu_cache in fremap.c, both defective.
The one in install_page needs to be accompanied by lazy_mmu_prot_update
(some other cleanup time, move that into ia64 update_mmu_cache itself); and
the one in install_file_pte should be removed since the pte is not present.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:52 -07:00
Hugh Dickins
70af7c5c64 [PATCH] swapoff: use atomic_inc_not_zero() on mm_users
Now that we have atomic_inc_not_zero, it's more elegant for try_to_unuse to
use that on mm_users: doesn't actually matter at present, but safer to be
sure that once mm_users has gone to 0, nothing raises it for an instant.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
David Howells
9637a5efd4 [PATCH] add page_mkwrite() vm_operations method
Add a new VMA operation to notify a filesystem or other driver about the
MMU generating a fault because userspace attempted to write to a page
mapped through a read-only PTE.

This facility permits the filesystem or driver to:

 (*) Implement storage allocation/reservation on attempted write, and so to
     deal with problems such as ENOSPC more gracefully (perhaps by generating
     SIGBUS).

 (*) Delay making the page writable until the contents have been written to a
     backing cache. This is useful for NFS/AFS when using FS-Cache/CacheFS.
     It permits the filesystem to have some guarantee about the state of the
     cache.

 (*) Account and limit number of dirty pages. This is one piece of the puzzle
     needed to make shared writable mapping work safely in FUSE.

Needed by cachefs (Or is it cachefiles?  Or fscache? <head spins>).

At least four other groups have stated an interest in it or a desire to use
the functionality it provides: FUSE, OCFS2, NTFS and JFFS2.  Also, things like
EXT3 really ought to use it to deal with the case of shared-writable mmap
encountering ENOSPC before we permit the page to be dirtied.

From: Peter Zijlstra <a.p.zijlstra@chello.nl>

  get_user_pages(.write=1, .force=1) can generate COW hits on read-only
  shared mappings, this patch traps those as mkpage_write candidates and fails
  to handle them the old way.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Joel Becker <Joel.Becker@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Andy Whitcroft
30c253e6da [PATCH] sparsemem: record nid during memory present
Record the node id as we mark sections for instantiation.  Use this nid
during instantiation to direct allocations.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Mike Kravetz <kravetz@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Bob Picco <bob.picco@hp.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Martin Bligh <mbligh@google.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Pekka Enberg
ddc2e812d5 [PATCH] slab: verify pointers before free
Passing an invalid pointer to kfree() and kmem_cache_free() is likely to
cause bad memory corruption or even take down the whole system because the
bad pointer is likely reused immediately due to the per-CPU caches.  Until
now, we don't do any verification for this if CONFIG_DEBUG_SLAB is
disabled.

As suggested by Linus, add PageSlab check to page_to_cache() and
page_to_slab() to verify pointers passed to kfree().  Also, move the
stronger check from cache_free_debugcheck() to kmem_cache_free() to ensure
the passed pointer actually belongs to the cache we're about to free the
object.

For page_to_cache() and page_to_slab(), the assertions should have
virtually no extra cost (two instructions, no data cache pressure) and for
kmem_cache_free() the overhead should be minimal.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
04e62a29bf [PATCH] More page migration: use migration entries for file pages
This implements the use of migration entries to preserve ptes of file backed
pages during migration.  Processes can therefore be migrated back and forth
without loosing their connection to pagecache pages.

Note that we implement the migration entries only for linear mappings.
Nonlinear mappings still require the unmapping of the ptes for migration.

And another writepage() ugliness shows up.  writepage() can drop the page
lock.  Therefore we have to remove migration ptes before calling writepages()
in order to avoid having migration entries point to unlocked pages.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
442c9137de [PATCH] More page migration: do not inc/dec rss counters
If we install a migration entry then the rss not really decreases since the
page is just moved somewhere else.  We can save ourselves the work of
decrementing and later incrementing which will just eventually cause cacheline
bouncing.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:51 -07:00
Christoph Lameter
6c5240ae7f [PATCH] Swapless page migration: modify core logic
Use the migration entries for page migration

This modifies the migration code to use the new migration entries.  It now
becomes possible to migrate anonymous pages without having to add a swap
entry.

We add a couple of new functions to replace migration entries with the proper
ptes.

We cannot take the tree_lock for migrating anonymous pages anymore.  However,
we know that we hold the only remaining reference to the page when the page
count reaches 1.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
d75a0fcda2 [PATCH] Swapless page migration: rip out swap based logic
Rip the page migration logic out.

Remove all code that has to do with swapping during page migration.

This also guts the ability to migrate pages to swap.  No one used that so lets
let it go for good.

Page migration should be a bit broken after this patch.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
0697212a41 [PATCH] Swapless page migration: add R/W migration entries
Implement read/write migration ptes

We take the upper two swapfiles for the two types of migration ptes and define
a series of macros in swapops.h.

The VM is modified to handle the migration entries.  migration entries can
only be encountered when the page they are pointing to is locked.  This limits
the number of places one has to fix.  We also check in copy_pte_range and in
mprotect_pte_range() for migration ptes.

We check for migration ptes in do_swap_cache and call a function that will
then wait on the page lock.  This allows us to effectively stop all accesses
to apge.

Migration entries are created by try_to_unmap if called for migration and
removed by local functions in migrate.c

From: Hugh Dickins <hugh@veritas.com>

  Several times while testing swapless page migration (I've no NUMA, just
  hacking it up to migrate recklessly while running load), I've hit the
  BUG_ON(!PageLocked(p)) in migration_entry_to_page.

  This comes from an orphaned migration entry, unrelated to the current
  correctly locked migration, but hit by remove_anon_migration_ptes as it
  checks an address in each vma of the anon_vma list.

  Such an orphan may be left behind if an earlier migration raced with fork:
  copy_one_pte can duplicate a migration entry from parent to child, after
  remove_anon_migration_ptes has checked the child vma, but before it has
  removed it from the parent vma.  (If the process were later to fault on this
  orphaned entry, it would hit the same BUG from migration_entry_wait.)

  This could be fixed by locking anon_vma in copy_one_pte, but we'd rather
  not.  There's no such problem with file pages, because vma_prio_tree_add
  adds child vma after parent vma, and the page table locking at each end is
  enough to serialize.  Follow that example with anon_vma: add new vmas to the
  tail instead of the head.

  (There's no corresponding problem when inserting migration entries,
  because a missed pte will leave the page count and mapcount high, which is
  allowed for.  And there's no corresponding problem when migrating via swap,
  because a leftover swap entry will be correctly faulted.  But the swapless
  method has no refcounting of its entries.)

From: Ingo Molnar <mingo@elte.hu>

  pte_unmap_unlock() takes the pte pointer as an argument.

From: Hugh Dickins <hugh@veritas.com>

  Several times while testing swapless page migration, gcc has tried to exec
  a pointer instead of a string: smells like COW mappings are not being
  properly write-protected on fork.

  The protection in copy_one_pte looks very convincing, until at last you
  realize that the second arg to make_migration_entry is a boolean "write",
  and SWP_MIGRATION_READ is 30.

  Anyway, it's better done like in change_pte_range, using
  is_write_migration_entry and make_migration_entry_read.

From: Hugh Dickins <hugh@veritas.com>

  Remove unnecessary obfuscation from sys_swapon's range check on swap type,
  which blew up causing memory corruption once swapless migration made
  MAX_SWAPFILES no longer 2 ^ MAX_SWAPFILES_SHIFT.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
From: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
8351a6e478 [PATCH] page migration cleanup: move fallback handling into special function
Move the fallback code into a new fallback function and make the function
behave like any other migration function.  This requires retaking the lock if
pageout() drops it.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
2d1db3b117 [PATCH] page migration cleanup: pass "mapping" to migration functions
Change handling of address spaces.

Pass a pointer to the address space in which the page is migrated to all
migration function.  This avoids repeatedly having to retrieve the address
space pointer from the page and checking it for validity.  The old page
mapping will change once migration has gone to a certain step, so it is less
confusing to have the pointer always available.

Move the setting of the mapping and index for the new page into
migrate_pages().

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
c3fcf8a5da [PATCH] page migration cleanup: extract try_to_unmap from migration functions
Extract try_to_unmap and rename remove_references -> move_mapping

try_to_unmap() may significantly change the page state by for example setting
the dirty bit.  It is therefore best to unmap in migrate_pages() before
calling any migration functions.

migrate_page_remove_references() will then only move the new page in place of
the old page in the mapping.  Rename the function to
migrate_page_move_mapping().

This allows us to get rid of the special unmapping for the fallback path.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
5b5c7120e2 [PATCH] page migration cleanup: drop nr_refs in remove_references()
Drop nr_refs parameter from migrate_page_remove_references()

The nr_refs parameter is not really useful since the number of remaining
references is always

1 for anonymous pages without a mapping
2 for pages with a mapping
3 for pages with a mapping and PagePrivate set.

Remove the early check for the number of references since we are checking
page_mapcount() earlier.  Ultimately only the refcount matters after the
tree_lock has been obtained.

Signed-off-by: Christoph Lameter <clameter@sgi.coim>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
e7340f7330 [PATCH] page migration cleanup: remove useless definitions
Remove the export for migrate_page_remove_references() and migrate_page_copy()
that are unlikely to be used directly by filesystems implementing migration.
The export was useful when buffer_migrate_page() lived in fs/buffer.c but it
has now been moved to migrate.c in the migration reorg.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
1d8b85ccf1 [PATCH] page migration cleanup: group functions
Reorder functions in migrate.c.  Group all migration functions for struct
address_space_operations together.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:50 -07:00
Christoph Lameter
7352349a19 [PATCH] page migration cleanup: rename "ignrefs" to "migration"
migrate is a better name since it is only used by page migration.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:49 -07:00
OGAWA Hirofumi
111ebb6e6f [PATCH] writeback: fix range handling
When a writeback_control's `start' and `end' fields are used to
indicate a one-byte-range starting at file offset zero, the required
values of .start=0,.end=0 mean that the ->writepages() implementation
has no way of telling that it is being asked to perform a range
request.  Because we're currently overloading (start == 0 && end == 0)
to mean "this is not a write-a-range request".

To make all this sane, the patch changes range of writeback_control.

So caller does: If it is calling ->writepages() to write pages, it
sets range (range_start/end or range_cyclic) always.

And if range_cyclic is true, ->writepages() thinks the range is
cyclic, otherwise it just uses range_start and range_end.

This patch does,

    - Add LLONG_MAX, LLONG_MIN, ULLONG_MAX to include/linux/kernel.h
      -1 is usually ok for range_end (type is long long). But, if someone did,

		range_end += val;		range_end is "val - 1"
		u64val = range_end >> bits;	u64val is "~(0ULL)"

      or something, they are wrong. So, this adds LLONG_MAX to avoid nasty
      things, and uses LLONG_MAX for range_end.

    - All callers of ->writepages() sets range_start/end or range_cyclic.

    - Fix updates of ->writeback_index. It seems already bit strange.
      If it starts at 0 and ended by check of nr_to_write, this last
      index may reduce chance to scan end of file.  So, this updates
      ->writeback_index only if range_cyclic is true or whole-file is
      scanned.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Steven French <sfrench@us.ibm.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:49 -07:00
Pekka Enberg
58ce1fd580 [PATCH] slab: redzone double-free detection
At present our slab debugging tells us that it detected a double-free or
corruption - it does not distinguish between them.  Sometimes it's useful
to be able to differentiate between these two types of information.

Add double-free detection to redzone verification when freeing an object.
As explained by Manfred, when we are freeing an object, both redzones
should be RED_ACTIVE.  However, if both are RED_INACTIVE, we are trying to
free an object that was already free'd.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:49 -07:00
Hua Zhong
b344e05c58 [PATCH] likely cleanup: remove unlikely in sys_mprotect()
With likely/unlikely profiling on my not-so-busy-typical-developmentsystem
there are 5k misses vs 2k hits.  So I guess we should remove the unlikely.

Signed-off-by: Hua Zhong <hzhong@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:49 -07:00
Nick Piggin
833423143c [PATCH] mm: introduce remap_vmalloc_range()
Add remap_vmalloc_range, vmalloc_user, and vmalloc_32_user so that drivers
can have a nice interface for remapping vmalloc memory.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:49 -07:00
Rafael J. Wysocki
d6277db4ab [PATCH] swsusp: rework memory shrinker
Rework the swsusp's memory shrinker in the following way:

- Simplify balance_pgdat() by removing all of the swsusp-related code
  from it.

- Make shrink_all_memory() use shrink_slab() and a new function
  shrink_all_zones() which calls shrink_active_list() and
  shrink_inactive_list() directly for each zone in a way that's optimized
  for suspend.

In shrink_all_memory() we try to free exactly as many pages as the caller
asks for, preferably in one shot, starting from easier targets.   If slab
caches are huge, they are most likely to have enough pages to reclaim.
 The inactive lists are next (the zones with more inactive pages go first)
etc.

Each time shrink_all_memory() attempts to shrink the active and inactive
lists for each zone in 5 passes.   In the first pass, only the inactive
lists are taken into consideration.   In the next two passes the active
lists are also shrunk, but mapped pages are not reclaimed.   In the last
two passes the active and inactive lists are shrunk and mapped pages are
reclaimed as well.  The aim of this is to alter the reclaim logic to choose
the best pages to keep on resume and improve the responsiveness of the
resumed system.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:48 -07:00
Christoph Hellwig
7a7c381d25 [PATCH] slab: stop using list_for_each
Use the _entry variant everywhere to clean the code up a tiny bit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:48 -07:00
Christoph Hellwig
e1b6aa6f14 [PATCH] slab: clean up kmem_getpages
The last ifdef addition hit the ugliness treshold on this functions, so:

 - rename the variable i to nr_pages so it's somewhat descriptive
 - remove the addr variable and do the page_address call at the very end
 - instead of ifdef'ing the whole alloc_pages_node call just make the
   __GFP_COMP addition to flags conditional
 - rewrite the __GFP_COMP comment to make sense

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:48 -07:00
Chen, Kenneth W
a43a8c39bb [PATCH] tightening hugetlb strict accounting
Current hugetlb strict accounting for shared mapping always assume mapping
starts at zero file offset and reserves pages between zero and size of the
file.  This assumption often reserves (or lock down) a lot more pages then
necessary if application maps at none zero file offset.  libhugetlbfs is
one example that requires proper reservation on shared mapping starts at
none zero offset.

This patch extends the reservation and hugetlb strict accounting to support
any arbitrary pair of (offset, len), resulting a much more robust and
accurate scheme.  More importantly, it won't lock down any hugetlb pages
outside file mapping.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Acked-by: Adam Litke <agl@us.ibm.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:48 -07:00
Dave Peterson
6937a25cff [PATCH] mm: fix typos in comments in mm/oom_kill.c
This fixes a few typos in the comments in mm/oom_kill.c.

Signed-off-by: David S. Peterson <dsp@llnl.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:47 -07:00
KAMEZAWA Hiroyuki
fadd8fbd15 [PATCH] support for panic at OOM
This patch adds panic_on_oom sysctl under sys.vm.

When sysctl vm.panic_on_oom = 1, the kernel panics intead of killing rogue
processes.  And if vm.panic_on_oom is 0 the kernel will do oom_kill() in
the same way as it does today.  Of course, the default value is 0 and only
root can modifies it.

In general, oom_killer works well and kill rogue processes.  So the whole
system can survive.  But there are environments where panic is preferable
rather than kill some processes.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:47 -07:00
Andy Whitcroft
67de648211 [PATCH] squash duplicate page_to_pfn and pfn_to_page
We have architectures where the size of page_to_pfn and pfn_to_page are
significant enough to overall image size that they wish to push them out of
line.  However, in the process we have grown a second copy of the
implementation of each of these routines for each memory model.  Share the
implmentation exposing it either inline or out-of-line as required.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:47 -07:00
Yasunori Goto
6811378e7d [PATCH] wait_table and zonelist initializing for memory hotadd: update zonelists
In current code, zonelist is considered to be build once, no modification.
But MemoryHotplug can add new zone/pgdat.  It must be updated.

This patch modifies build_all_zonelists().  By this, build_all_zonelist() can
reconfig pgdat's zonelists.

To update them safety, this patch use stop_machine_run().  Other cpus don't
touch among updating them by using it.

In old version (V2 of node hotadd), kernel updated them after zone
initialization.  But present_page of its new zone is still 0, because
online_page() is not called yet at this time.  Build_zonelists() checks
present_pages to find present zone.  It was too early.  So, I changed it after
online_pages().

Signed-off-by: Yasunori Goto     <y-goto@jp.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Yasunori Goto
cca448fe92 [PATCH] wait_table and zonelist initializing for memory hotadd: wait_table initialization
Wait_table is initialized according to zone size at boot time.  But, we cannot
know the maixmum zone size when memory hotplug is enabled.  It can be
changed....  And resizing of wait_table is hard.

So kernel allocate and initialzie wait_table as its maximum size.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Yasunori Goto
718127cc31 [PATCH] wait_table and zonelist initializing for memory hotadd: add return code for init_current_empty_zone
When add_zone() is called against empty zone (not populated zone), we have to
initialize the zone which didn't initialize at boot time.  But,
init_currently_empty_zone() may fail due to allocation of wait table.  So,
this patch is to catch its error code.

Changes against wait_table is in the next patch.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Yasunori Goto
86356ab147 [PATCH] wait_table and zonelist initializing for memory hotadd: change to meminit for build_zonelist
Change definitions of some functions and data from __init to __meminit.

These functions and data can be used after bootup by this patch to be used for
hot-add codes.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Yasunori Goto
02b694dea4 [PATCH] wait_table and zonelist initializing for memory hotadd: change name of wait_table_size()
This is just to rename from wait_table_size() to wait_table_hash_nr_entries().

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Christoph Lameter
3c5a87f476 [PATCH] migration: remove unnecessary PageSwapCache checks
Remove two unnecessary PageSwapCache checks.  The page refcount is raised
and therefore page migration cannot occur in both functions.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Pekka Enberg
4776874ff0 [PATCH] slab: page mapping cleanup
Clean up slab allocator page mapping a bit.  The memory allocated for a
slab is physically contiguous so it is okay to assume struct pages are too
so kill the long-standing comment.  Furthermore, rename set_slab_attr to
slab_map_pages and add a comment explaining why its needed.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Pekka Enberg
729bd0b74c [PATCH] slab: extract cache_free_alien from __cache_free
Move alien object freeing to cache_free_alien() to reduce #ifdef clutter in
__cache_free().

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:46 -07:00
Christoph Lameter
4da5eda0dc [PATCH] Page Migration: Make do_swap_page redo the fault
It is better to redo the complete fault if do_swap_page() finds that the
page is not in PageSwapCache() because the page migration code may have
replaced the swap pte already with a pte pointing to valid memory.

do_swap_page() may interpret an invalid swap entry without this patch
because we do not reload the pte if we are looping back.  The page
migration code may already have reused the swap entry referenced by our
local swp_entry.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
Andy Whitcroft
cb2b95e1c6 [PATCH] zone handle unaligned zone boundaries
The buddy allocator has a requirement that boundaries between contigious
zones occur aligned with the the MAX_ORDER ranges.  Where they do not we
will incorrectly merge pages cross zone boundaries.  This can lead to pages
from the wrong zone being handed out.

Originally the buddy allocator would check that buddies were in the same
zone by referencing the zone start and end page frame numbers.  This was
removed as it became very expensive and the buddy allocator already made
the assumption that zones boundaries were aligned.

It is clear that not all configurations and architectures are honouring
this alignment requirement.  Therefore it seems safest to reintroduce
support for non-aligned zone boundaries.  This patch introduces a new check
when considering a page a buddy it compares the zone_table index for the
two pages and refuses to merge the pages where they do not match.  The
zone_table index is unique for each node/zone combination when
FLATMEM/DISCONTIGMEM is enabled and for each section/zone combination when
SPARSEMEM is enabled (a SPARSEMEM section is at least a MAX_ORDER size).

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
David Howells
726c334223 [PATCH] VFS: Permit filesystem to perform statfs with a known root dentry
Give the statfs superblock operation a dentry pointer rather than a superblock
pointer.

This complements the get_sb() patch.  That reduced the significance of
sb->s_root, allowing NFS to place a fake root there.  However, NFS does
require a dentry to use as a target for the statfs operation.  This permits
the root in the vfsmount to be used instead.

linux/mount.h has been added where necessary to make allyesconfig build
successfully.

Interest has also been expressed for use with the FUSE and XFS filesystems.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
David Howells
454e2398be [PATCH] VFS: Permit filesystem to override root dentry on mount
Extend the get_sb() filesystem operation to take an extra argument that
permits the VFS to pass in the target vfsmount that defines the mountpoint.

The filesystem is then required to manually set the superblock and root dentry
pointers.  For most filesystems, this should be done with simple_set_mnt()
which will set the superblock pointer and then set the root dentry to the
superblock's s_root (as per the old default behaviour).

The get_sb() op now returns an integer as there's now no need to return the
superblock pointer.

This patch permits a superblock to be implicitly shared amongst several mount
points, such as can be done with NFS to avoid potential inode aliasing.  In
such a case, simple_set_mnt() would not be called, and instead the mnt_root
and mnt_sb would be set directly.

The patch also makes the following changes:

 (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount
     pointer argument and return an integer, so most filesystems have to change
     very little.

 (*) If one of the convenience function is not used, then get_sb() should
     normally call simple_set_mnt() to instantiate the vfsmount. This will
     always return 0, and so can be tail-called from get_sb().

 (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the
     dcache upon superblock destruction rather than shrink_dcache_anon().

     This is required because the superblock may now have multiple trees that
     aren't actually bound to s_root, but that still need to be cleaned up. The
     currently called functions assume that the whole tree is rooted at s_root,
     and that anonymous dentries are not the roots of trees which results in
     dentries being left unculled.

     However, with the way NFS superblock sharing are currently set to be
     implemented, these assumptions are violated: the root of the filesystem is
     simply a dummy dentry and inode (the real inode for '/' may well be
     inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries
     with child trees.

     [*] Anonymous until discovered from another tree.

 (*) The documentation has been adjusted, including the additional bit of
     changing ext2_* into foo_* in the documentation.

[akpm@osdl.org: convert ipath_fs, do other stuff]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:45 -07:00
Steven Whitehouse
bf9f424d9a [GFS2] Make file_read_actor export _GPL
Make file_read_actor export a _GPL export.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-06-21 11:54:43 -04:00
Trond Myklebust
d59bf96cdd Merge branch 'master' of /home/trondmy/kernel/linux-2.6/ 2006-06-20 08:59:45 -04:00
Steven Whitehouse
2b3d6e2f23 Merge branch 'master' 2006-06-19 09:21:08 -04:00
Sergey Vlasov
86bc843a26 [PATCH] tmpfs: Decrement i_nlink correctly in shmem_rmdir()
shmem_rmdir() must undo the increment of i_nlink done in
shmem_get_inode() for directories, otherwise at least
IN_DELETE_SELF inotify event generation is broken.

Signed-off-by: Sergey Vlasov <vsu@altlinux.ru>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-12 14:29:04 -07:00
Robin H. Johnson
cfd95a9cf5 [PATCH] tmpfs: time granularity fix for [acm]time going backwards
I noticed a strange behavior in a tmpfs file system the other day, while
building packages - occasionally, and seemingly at random, make decided to
rebuild a target. However, only on tmpfs.

A file would be created, and if checked, it had a sub-second timestamp.
However, after an utimes related call where sub-seconds should be set, they
were zeroed instead. In the case that a file was created, and utimes(...,NULL)
was used on it in the same second, the timestamp on the file moved backwards.

After some digging, I found that this was being caused by tmpfs not having a
time granularity set, thus inheriting the default 1 second granularity.

Hugh adds: yes, we missed tmpfs when the s_time_gran mods went into 2.6.11.
Unfortunately, the granularity of CURRENT_TIME, often used in filesystems,
does not match the default granularity set by alloc_super.  A few more such
discrepancies have been found, but this is the most important to fix now.

Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-12 13:55:52 -07:00
Christoph Lameter
c0bbbc73d5 [PATCH] typo in vmscan.c
From: Christoph Lameter <clameter@sgi.com>

Looks like a comma was left from the conversion from a struct to an
assignment.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-11 15:27:37 -07:00
Trond Myklebust
1f5ce9e93a VFS: Unexport do_kern_mount() and clean up simple_pin_fs()
Replace all module uses with the new vfs_kern_mount() interface, and fix up
simple_pin_fs().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-09 09:34:16 -04:00
Steven Whitehouse
4b01abc977 Merge branch 'master' 2006-06-06 10:31:26 -04:00
Ingo Molnar
b1ab41c494 [PATCH] slab.c: fix offslab_limit bug
mm/slab.c's offlab_limit logic is totally broken.

Firstly, "offslab_limit" is a global variable while it should either be
calculated in situ or should be passed in as a parameter.

Secondly, the more serious problem with it is that the condition for
calculating it:

               if (!(OFF_SLAB(sizes->cs_cachep))) {
                       offslab_limit = sizes->cs_size - sizeof(struct slab);
                       offslab_limit /= sizeof(kmem_bufctl_t);

is in total disconnect with the condition that makes use of it:

               /* More than offslab_limit objects will cause problems */
               if ((flags & CFLGS_OFF_SLAB) && num > offslab_limit)
                       break;

but due to offslab_limit being a global variable this breakage was
hidden.

Up until lockdep came along and perturbed the slab sizes sufficiently so
that the first off-slab cache would still see a (non-calculated) zero
value for offslab_limit and would panic with:

  kmem_cache_create: couldn't create cache size-512.

  Call Trace:
   [<ffffffff8020a5b9>] show_trace+0x96/0x1c8
   [<ffffffff8020a8f0>] dump_stack+0x13/0x15
   [<ffffffff8022994f>] panic+0x39/0x21a
   [<ffffffff80270814>] kmem_cache_create+0x5a0/0x5d0
   [<ffffffff80aced62>] kmem_cache_init+0x193/0x379
   [<ffffffff80abf779>] start_kernel+0x17f/0x218
   [<ffffffff80abf263>] _sinittext+0x263/0x26a

  Kernel panic - not syncing: kmem_cache_create(): failed to create slab `size-512'

Paolo Ornati's config on x86_64 managed to trigger it.

The fix is to move the calculation to the place that makes use of it.
This also makes slab.o 54 bytes smaller.

Btw., the check itself is quite silly. Its intention is to test whether
the number of objects per slab would be higher than the number of slab
control pointers possible. In theory it could be triggered: if someone
tried to allocate 4-byte objects cache and explicitly requested with
CFLGS_OFF_SLAB. So i kept the check.

Out of historic interest i checked how old this bug was and it's
ancient, 10 years old! It is the oldest hidden and then truly triggering
bugs i ever saw being fixed in the kernel!

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-02 11:21:10 -07:00
Yasunori Goto
25a6df9525 [PATCH] spanned_pages is not updated at a case of memory hot-add
From: Yasunori Goto <y-goto@jp.fujitsu.com>

If hot-added memory's address is smaller than old area, spanned_pages will
not be updated.  It must be fixed.

example) Old zone_start_pfn = 0x60000, and spanned_pages = 0x10000
         Added new memory's start_pfn = 0x50000, and end_pfn = 0x60000

  new spanned_pages will be still 0x10000 by old code.
  (It should be updated to 0x20000.) Because old_zone_end_pfn will be
  0x70000, and end_pfn smaller than it. So, spanned_pages will not be
  updated.

In current code, spanned_pages is updated only when end_pfn is updated.
But, it should be updated by subtraction between bigger end_pfn and new
zone_start_pfn.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-31 16:27:10 -07:00
Steven Whitehouse
c6a756795d Merge branch 'master' 2006-05-25 12:40:08 -04:00
Bob Picco
e984bb43f7 [PATCH] Align the node_mem_map endpoints to a MAX_ORDER boundary
Andy added code to buddy allocator which does not require the zone's
endpoints to be aligned to MAX_ORDER.  An issue is that the buddy allocator
requires the node_mem_map's endpoints to be MAX_ORDER aligned.  Otherwise
__page_find_buddy could compute a buddy not in node_mem_map for partial
MAX_ORDER regions at zone's endpoints.  page_is_buddy will detect that
these pages at endpoints are not PG_buddy (they were zeroed out by bootmem
allocator and not part of zone).  Of course the negative here is we could
waste a little memory but the positive is eliminating all the old checks
for zone boundary conditions.

SPARSEMEM won't encounter this issue because of MAX_ORDER size constraint
when SPARSEMEM is configured.  ia64 VIRTUAL_MEM_MAP doesn't need the logic
either because the holes and endpoints are handled differently.  This
leaves checking alloc_remap and other arches which privately allocate for
node_mem_map.

Signed-off-by: Bob Picco <bob.picco@hp.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-21 12:59:22 -07:00
Paul Jackson
bdd804f478 [PATCH] Cpuset: might sleep checking zones allowed fix
Fix a couple of infrequently encountered 'sleeping function called from
invalid context' in the cpuset hooks in __alloc_pages.  Could sleep while
interrupts disabled.

The routine cpuset_zone_allowed() is called by code in mm/page_alloc.c
__alloc_pages() to determine if a zone is allowed in the current tasks
cpuset.  This routine can sleep, for certain GFP_KERNEL allocations, if the
zone is on a memory node not allowed in the current cpuset, but might be
allowed in a parent cpuset.

But we can't sleep in __alloc_pages() if in interrupt, nor if called for a
GFP_ATOMIC request (__GFP_WAIT not set in gfp_flags).

The rule was intended to be:
  Don't call cpuset_zone_allowed() if you can't sleep, unless you
  pass in the __GFP_HARDWALL flag set in gfp_flag, which disables
  the code that might scan up ancestor cpusets and sleep.

This rule was being violated in a couple of places, due to a bogus change
made (by myself, pj) to __alloc_pages() as part of the November 2005 effort
to cleanup its logic, and also due to a later fix to constrain which swap
daemons were awoken.

The bogus change can be seen at:
  http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-11/4691.html
  [PATCH 01/05] mm fix __alloc_pages cpuset ALLOC_* flags

This was first noticed on a tight memory system, in code that was disabling
interrupts and doing allocation requests with __GFP_WAIT not set, which
resulted in __might_sleep() writing complaints to the log "Debug: sleeping
function called ...", when the code in cpuset_zone_allowed() tried to take
the callback_sem cpuset semaphore.

We haven't seen a system hang on this 'might_sleep' yet, but we are at
decent risk of seeing it fairly soon, especially since the additional
cpuset_zone_allowed() check was added, conditioning wakeup_kswapd(), in
March 2006.

Special thanks to Dave Chinner, for figuring this out, and a tip of the hat
to Nick Piggin who warned me of this back in Nov 2005, before I was ready
to listen.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-21 12:59:18 -07:00
Mike Kravetz
12783b002d [PATCH] SPARSEMEM incorrectly calculates section number
A bad calculation/loop in __section_nr() could result in incorrect section
information being put into sysfs memory entries.  This primarily impacts
memory add operations as the sysfs information is used while onlining new
memory.

Fix suggested by Dave Hansen.

Note that the bug may not be obvious from the patch.  It actually occurs in
the function's return statement:

	return (root_nr * SECTIONS_PER_ROOT) + (ms - root);

In the existing code, root_nr has already been multiplied by
SECTIONS_PER_ROOT.

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-21 12:59:17 -07:00
Roland Dreier
a4523a8b38 [PATCH] slab: Fix kmem_cache_destroy() on NUMA
With CONFIG_NUMA set, kmem_cache_destroy() may fail and say "Can't
free all objects."  The problem is caused by sequences such as the
following (suppose we are on a NUMA machine with two nodes, 0 and 1):

 * Allocate an object from cache on node 0.
 * Free the object on node 1.  The object is put into node 1's alien
   array_cache for node 0.
 * Call kmem_cache_destroy(), which ultimately ends up in __cache_shrink().
 * __cache_shrink() does drain_cpu_caches(), which loops through all nodes.
   For each node it drains the shared array_cache and then handles the
   alien array_cache for the other node.

However this means that node 0's shared array_cache will be drained,
and then node 1 will move the contents of its alien[0] array_cache
into that same shared array_cache.  node 0's shared array_cache is
never looked at again, so the objects left there will appear to be in
use when __cache_shrink() calls __node_shrink() for node 0.  So
__node_shrink() will return 1 and kmem_cache_destroy() will fail.

This patch fixes this by having drain_cpu_caches() do
drain_alien_cache() on every node before it does drain_array() on the
nodes' shared array_caches.

The problem was originally reported by Or Gerlitz <ogerlitz@voltaire.com>.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-16 07:59:32 -07:00
Mike Kravetz
39d24e6426 [PATCH] add slab_is_available() routine for boot code
slab_is_available() indicates slab based allocators are available for use.
SPARSEMEM code needs to know this as it can be called at various times
during the boot process.

Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-15 11:20:56 -07:00