Commit Graph

240976 Commits

Author SHA1 Message Date
Nick Piggin
89699605fe mm: vmap area cache
Provide a free area cache for the vmalloc virtual address allocator, based
on the algorithm used by the user virtual memory allocator.

This reduces the number of rbtree operations and linear traversals over
the vmap extents in order to find a free area, by starting off at the last
point that a free area was found.

The free area cache is reset if areas are freed behind it, or if we are
searching for a smaller area or alignment than last time.  So allocation
patterns are not changed (verified by corner-case and random test cases in
userspace testing).

This solves a regression caused by lazy vunmap TLB purging introduced in
db64fe02 (mm: rewrite vmap layer).  That patch will leave extents in the
vmap allocator after they are vunmapped, and until a significant number
accumulate that can be flushed in a single batch.  So in a workload that
vmalloc/vfree frequently, a chain of extents will build up from
VMALLOC_START address, which have to be iterated over each time (giving an
O(n) type of behaviour).

After this patch, the search will start from where it left off, giving
closer to an amortized O(1).

This is verified to solve regressions reported Steven in GFS2, and Avi in
KVM.

Hugh's update:

: I tried out the recent mmotm, and on one machine was fortunate to hit
: the BUG_ON(first->va_start < addr) which seems to have been stalling
: your vmap area cache patch ever since May.

: I can get you addresses etc, I did dump a few out; but once I stared
: at them, it was easier just to look at the code: and I cannot see how
: you would be so sure that first->va_start < addr, once you've done
: that addr = ALIGN(max(...), align) above, if align is over 0x1000
: (align was 0x8000 or 0x4000 in the cases I hit: ioremaps like Steve).

: I originally got around it by just changing the
: 		if (first->va_start < addr) {
: to
: 		while (first->va_start < addr) {
: without thinking about it any further; but that seemed unsatisfactory,
: why would we want to loop here when we've got another very similar
: loop just below it?

: I am never going to admit how long I've spent trying to grasp your
: "while (n)" rbtree loop just above this, the one with the peculiar
: 		if (!first && tmp->va_start < addr + size)
: in.  That's unfamiliar to me, I'm guessing it's designed to save a
: subsequent rb_next() in a few circumstances (at risk of then setting
: a wrong cached_hole_size?); but they did appear few to me, and I didn't
: feel I could sign off something with that in when I don't grasp it,
: and it seems responsible for extra code and mistaken BUG_ON below it.

: I've reverted to the familiar rbtree loop that find_vma() does (but
: with va_end >= addr as you had, to respect the additional guard page):
: and then (given that cached_hole_size starts out 0) I don't see the
: need for any complications below it.  If you do want to keep that loop
: as you had it, please add a comment to explain what it's trying to do,
: and where addr is relative to first when you emerge from it.

: Aren't your tests "size <= cached_hole_size" and
: "addr + size > first->va_start" forgetting the guard page we want
: before the next area?  I've changed those.

: I have not changed your many "addr + size - 1 < addr" overflow tests,
: but have since come to wonder, shouldn't they be "addr + size < addr"
: tests - won't the vend checks go wrong if addr + size is 0?

: I have added a few comments - Wolfgang Wander's 2.6.13 description of
: 1363c3cd86 Avoiding mmap fragmentation
: helped me a lot, perhaps a pointer to that would be good too.  And I found
: it easier to understand when I renamed cached_start slightly and moved the
: overflow label down.

: This patch would go after your mm-vmap-area-cache.patch in mmotm.
: Trivially, nobody is going to get that BUG_ON with this patch, and it
: appears to work fine on my machines; but I have not given it anything like
: the testing you did on your original, and may have broken all the
: performance you were aiming for.  Please take a look and test it out
: integrate with yours if you're satisfied - thanks.

[akpm@linux-foundation.org: add locking comment]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Reported-and-tested-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-and-tested-by: Avi Kivity <avi@redhat.com>
Tested-by: "Barry J. Marson" <bmarson@redhat.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Robert Morell
ef0a5e80f5 pwm_backlight: add check_fb() hook
In systems with multiple framebuffer devices, one of the devices might be
blanked while another is unblanked.  In order for the backlight blanking
logic to know whether to turn off the backlight for a particular
framebuffer's blanking notification, it needs to be able to check if a
given framebuffer device corresponds to the backlight.

This plumbs the check_fb hook from core backlight through the
pwm_backlight helper to allow platform code to plug in a check_fb hook.

Signed-off-by: Robert Morell <rmorell@nvidia.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Arun Murthy <arun.murthy@stericsson.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Axel Lin
0508e04e05 drivers/video/backlight/jornada720_*.c: make needlessly global symbols static
The following symbols are needlessly defined global: jornada_bl_init,
jornada_bl_exit, jornada_lcd_init, jornada_lcd_exit.

Make them static.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Kristoffer Ericson <kristoffer.ericson@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Randy Dunlap
b372412e15 backlight: apple_bl depends on ACPI
apple_bl uses ACPI interfaces (data & code), so it should depend on ACPI.

  drivers/video/backlight/apple_bl.c:142: warning: 'struct acpi_device' declared inside parameter list
  drivers/video/backlight/apple_bl.c:142: warning: its scope is only this definition or declaration, which is probably not what you want
  drivers/video/backlight/apple_bl.c:201: warning: 'struct acpi_device' declared inside parameter list
  drivers/video/backlight/apple_bl.c:215: error: variable 'apple_bl_driver' has initializer but incomplete type
  drivers/video/backlight/apple_bl.c:216: error: unknown field 'name' specified in initializer
  ...

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Matthew Garrett
39b3dee76f mbp_nvidia_bl: rename to apple_bl
It works on hardware other than Macbook Pros, and it works on GPUs other
than Nvidia.  It should even work on iMacs, so change the name to match
reality more precisely and include an alias so existing users don't get
confused.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Mourad De Clerck <mourad@aquazul.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Matthew Garrett
99fd28e194 mbp_nvidia_bl: check that the backlight control functions
The SMI-based backlight control functionality may fail to work if the
system is running under EFI rather than BIOS.  Check that the hardware
responds as expected, and exit if it doesn't.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Mourad De Clerck <mourad@aquazul.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Matthew Garrett
23a9847f0d mbp_nvidia_bl: remove DMI dependency
This driver only has to deal with two different classes of hardware, but
right now it needs new DMI entries for every new machine. It turns out
that there's an ACPI device that uniquely identifies Apples with backlights,
so this patch reworks the driver into an ACPI one, identifies the hardware
by checking the PCI vendor of the root bridge and strips out all the DMI
code. It also changes the config text to clarify that it works on devices
other than Macbook Pros and GPUs other than nvidia.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Mourad De Clerck <mourad@aquazul.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Matthew Garrett
9661e92c10 acpi: tie ACPI backlight devices to PCI devices if possible
Dual-GPU machines may provide more than one ACPI backlight interface.  Tie
the backlight device to the GPU in order to allow userspace to identify
the correct interface.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:00 -07:00
Matthew Garrett
7eae3efa13 nouveau: change the backlight parent device to the connector, not the PCI dev
We may eventually end up with per-connector backlights, especially with
ddcci devices.  Make sure that the parent node for the backlight device is
the connector rather than the PCI device.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Acked-by: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Michel Dänzer
63ec0119d3 radeon: expose backlight class device for legacy LVDS encoder
Allows e.g. power management daemons to control the backlight level. Inspired
by the corresponding code in radeonfb.

[mjg@redhat.com: updated to add backlight type and make the connector the parent device]
Signed-off-by: Michel Dänzer <michel@daenzer.net>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Acked-by: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: Sedat Dilek <sedat.dilek@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Matthew Garrett
bb7ca747f8 backlight: add backlight type
There may be multiple ways of controlling the backlight on a given
machine.  Allow drivers to expose the type of interface they are
providing, making it possible for userspace to make appropriate policy
decisions.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Vasiliy Kulikov
ccd7510fd8 drivers/leds/leds-lp5523.c: world-writable engine* sysfs files
Don't allow everybody to change LED settings.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Vasiliy Kulikov
67d1da79b2 drivers/leds/leds-lp5521.c: world-writable sysfs engine* files
Don't allow everybody to change LED settings.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Donghwa Lee
1baf0eb397 drivers/vidfeo/backlight: ld9040 amoled driver support
Add a ld9040 amoled panel driver.

Signed-off-by: Donghwa Lee <dh09.lee@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Uwe Kleine-König
9517f925f2 leds: make *struct gpio_led_platform_data.leds const
And fix a typo.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Shreshtha Kumar Sahu
b1e6b7068f leds: add driver for LM3530 ALS
Simple backlight driver for National Semiconductor LM3530.  Presently only
manual mode is supported, PWM and ALS support to be added.

Signed-off-by: Shreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:59 -07:00
Mark Brown
551ea73838 leds: convert bd2802 driver to dev_pm_ops
There is a move to deprecate bus-specific PM operations and move to using
dev_pm_ops instead in order to reduce the amount of boilerplate code in
buses and facilitiate updates to the PM core.  Do this move for the bs2802
driver.

[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Kim Kyuwon <q1.kim@samsung.com>
Cc: Kim Kyuwon <chammoru@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
Phil Carmody
8d2587970b cgroups: if you list_empty() a head then don't list_del() it
list_del() leaves poison in the prev and next pointers.  The next
list_empty() will compare those poisons, and say the list isn't empty.
Any list operations that assume the node is on a list because of such a
check will be fooled into dereferencing poison.  One needs to INIT the
node after the del, and fortunately there's already a wrapper for that -
list_del_init().

Some of the dels are followed by deallocations, so can be ignored, and one
can be merged with an add to make a move.  Apart from that, I erred on the
side of caution in making nodes list_empty()-queriable.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
David Rientjes
edd45544c6 oom: avoid deferring oom killer if exiting task is being traced
The oom killer naturally defers killing anything if it finds an eligible
task that is already exiting and has yet to detach its ->mm.  This avoids
unnecessarily killing tasks when one is already in the exit path and may
free enough memory that the oom killer is no longer needed.  This is
detected by PF_EXITING since threads that have already detached its ->mm
are no longer considered at all.

The problem with always deferring when a thread is PF_EXITING, however, is
that it may never actually exit when being traced, specifically if another
task is tracing it with PTRACE_O_TRACEEXIT.  The oom killer does not want
to defer in this case since there is no guarantee that thread will ever
exit without intervention.

This patch will now only defer the oom killer when a thread is PF_EXITING
and no ptracer has stopped its progress in the exit path.  It also ensures
that a child is sacrificed for the chosen parent only if it has a
different ->mm as the comment implies: this ensures that the thread group
leader is always targeted appropriately.

Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: <stable@kernel.org>		[2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
Andrey Vagin
30e2b41f20 oom: skip zombies when iterating tasklist
We shouldn't defer oom killing if a thread has already detached its ->mm
and still has TIF_MEMDIE set.  Memory needs to be freed, so find kill
other threads that pin the same ->mm or find another task to kill.

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@kernel.org>		[2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
David Rientjes
3a5dda7a17 oom: prevent unnecessary oom kills or kernel panics
This patch prevents unnecessary oom kills or kernel panics by reverting
two commits:

	495789a5 (oom: make oom_score to per-process value)
	cef1d352 (oom: multi threaded process coredump don't make deadlock)

First, 495789a5 (oom: make oom_score to per-process value) ignores the
fact that all threads in a thread group do not necessarily exit at the
same time.

It is imperative that select_bad_process() detect threads that are in the
exit path, specifically those with PF_EXITING set, to prevent needlessly
killing additional tasks.  If a process is oom killed and the thread group
leader exits, select_bad_process() cannot detect the other threads that
are PF_EXITING by iterating over only processes.  Thus, it currently
chooses another task unnecessarily for oom kill or panics the machine when
nothing else is eligible.

By iterating over threads instead, it is possible to detect threads that
are exiting and nominate them for oom kill so they get access to memory
reserves.

Second, cef1d352 (oom: multi threaded process coredump don't make
deadlock) erroneously avoids making the oom killer a no-op when an
eligible thread other than current isfound to be exiting.  We want to
detect this situation so that we may allow that exiting thread time to
exit and free its memory; if it is able to exit on its own, that should
free memory so current is no loner oom.  If it is not able to exit on its
own, the oom killer will nominate it for oom kill which, in this case,
only means it will get access to memory reserves.

Without this change, it is easy for the oom killer to unnecessarily target
tasks when all threads of a victim don't exit before the thread group
leader or, in the worst case, panic the machine.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: <stable@kernel.org>		[2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
Mel Gorman
52c50567d8 mm: swap: unlock swapfile inode mutex before closing file on bad swapfiles
If an administrator tries to swapon a file backed by NFS, the inode mutex is
taken (as it is for any swapfile) but later identified to be a bad swapfile
due to the lack of bmap and tries to cleanup. During cleanup, an attempt is
made to close the file but with inode->i_mutex still held. Closing an NFS
file syncs it which tries to acquire the inode mutex leading to deadlock. If
lockdep is enabled the following appears on the console;

    =============================================
    [ INFO: possible recursive locking detected ]
    2.6.38-rc8-autobuild #1
    ---------------------------------------------
    swapon/2192 is trying to acquire lock:
     (&sb->s_type->i_mutex_key#13){+.+.+.}, at: vfs_fsync_range+0x47/0x7c

    but task is already holding lock:
     (&sb->s_type->i_mutex_key#13){+.+.+.}, at: sys_swapon+0x28d/0xae7

    other info that might help us debug this:
    1 lock held by swapon/2192:
     #0:  (&sb->s_type->i_mutex_key#13){+.+.+.}, at: sys_swapon+0x28d/0xae7

    stack backtrace:
    Pid: 2192, comm: swapon Not tainted 2.6.38-rc8-autobuild #1
    Call Trace:
        __lock_acquire+0x2eb/0x1623
        find_get_pages_tag+0x14a/0x174
        pagevec_lookup_tag+0x25/0x2e
        vfs_fsync_range+0x47/0x7c
        lock_acquire+0xd3/0x100
        vfs_fsync_range+0x47/0x7c
        nfs_flush_one+0x0/0xdf [nfs]
        mutex_lock_nested+0x40/0x2b1
        vfs_fsync_range+0x47/0x7c
        vfs_fsync_range+0x47/0x7c
        vfs_fsync+0x1c/0x1e
        nfs_file_flush+0x64/0x69 [nfs]
        filp_close+0x43/0x72
        sys_swapon+0xa39/0xae7
        sysret_check+0x2e/0x69
        system_call_fastpath+0x16/0x1b

This patch releases the mutex if its held before calling filep_close()
so swapon fails as expected without deadlock when the swapfile is backed
by NFS.  If accepted for 2.6.39, it should also be considered a -stable
candidate for 2.6.38 and 2.6.37.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: <stable@kernel.org>		[2.6.37+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
Andrew Morton
c7a1fcd8e6 include/asm-generic/unistd.h: fix syncfs syscall number
syncfs() is duplicating name_to_handle_at() due to a merging mistake.

Cc: Sage Weil <sage@newdream.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:43:58 -07:00
Linus Torvalds
01ba825146 Merge branch 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: Add statistics for this_cmpxchg_double failures
  slub: Add missing irq restore for the OOM path
2011-03-22 16:26:57 -07:00
Linus Torvalds
ab70a1d7c7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  [net/9p]: Introduce basic flow-control for VirtIO transport.
  9p: use the updated offset given by generic_write_checks
  [net/9p] Don't re-pin pages on retrying virtqueue_add_buf().
  [net/9p] Set the condition just before waking up.
  [net/9p] unconditional wake_up to proc waiting for space on VirtIO ring
  fs/9p: Add v9fs_dentry2v9ses
  fs/9p: Attach writeback_fid on first open with WR flag
  fs/9p: Open writeback fid in O_SYNC mode
  fs/9p: Use truncate_setsize instead of vmtruncate
  net/9p: Fix compile warning
  net/9p: Convert the in the 9p rpc call path to GFP_NOFS
  fs/9p: Fix race in initializing writeback fid
2011-03-22 16:26:10 -07:00
Linus Torvalds
0adfc56ce8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: use watch/notify for changes in rbd header
  libceph: add lingering request and watch/notify event framework
  rbd: update email address in Documentation
  ceph: rename dentry_release -> d_release, fix comment
  ceph: add request to the tail of unsafe write list
  ceph: remove request from unsafe list if it is canceled/timed out
  ceph: move readahead default to fs/ceph from libceph
  ceph: add ino32 mount option
  ceph: update common header files
  ceph: remove debugfs debug cruft
  libceph: fix osd request queuing on osdmap updates
  ceph: preserve I_COMPLETE across rename
  libceph: Fix base64-decoding when input ends in newline.
2011-03-22 16:25:25 -07:00
Linus Torvalds
f23eb2b2b2 tty: stop using "delayed_work" in the tty layer
Using delayed-work for tty flip buffers ends up causing us to wait for
the next tick to complete some actions.  That's usually not all that
noticeable, but for certain latency-critical workloads it ends up being
totally unacceptable.

As an extreme case of this, passing a token back-and-forth over a pty
will take two ticks per iteration, so even just a thousand iterations
will take 8 seconds assuming a common 250Hz configuration.

Avoiding the whole delayed work issue brings that ping-pong test-case
down to 0.009s on my machine.

In more practical terms, this latency has been a performance problem for
things like dive computer simulators (simulating the serial interface
using the ptys) and for other environments (Alan mentions a CP/M emulator).

Reported-by: Jef Driesen <jefdriesen@telenet.be>
Acked-by: Greg KH <gregkh@suse.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 16:17:32 -07:00
Venkateswararao Jujjuri (JV)
68da9ba4ee [net/9p]: Introduce basic flow-control for VirtIO transport.
Recent zerocopy work in the 9P VirtIO transport maps and pins
user buffers into kernel memory for the server to work on them.
Since the user process can initiate this kind of pinning with a simple
read/write call, thousands of IO threads initiated by the user process can
hog the system resources and could result into denial of service.

This patch introduces flow control to avoid that extreme scenario.

The ceiling limit to avoid denial of service attacks is set to relatively
high (nr_free_pagecache_pages()/4) so that it won't interfere with
regular usage, but can step in extreme cases to limit the total system
hang. Since we don't have a global structure to accommodate this variable,
I choose the virtio_chan as the home for this.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Reviewed-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 16:32:50 -05:00
M. Mohan Kumar
aaf0ef1d2b 9p: use the updated offset given by generic_write_checks
Without this fix, even if a file is opened in O_APPEND mode, data will be
written at current file position instead of end of file.

Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 16:32:49 -05:00
Venkateswararao Jujjuri (JV)
316ad5501c [net/9p] Don't re-pin pages on retrying virtqueue_add_buf().
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 16:32:48 -05:00
Venkateswararao Jujjuri (JV)
a01a984035 [net/9p] Set the condition just before waking up.
Given that the sprious wake-ups are common, we need to move the
condition setting right next to the wake_up().  After setting the condition
to req->status = REQ_STATUS_RCVD, sprious wakeups may cause the
virtqueue back on the free list for someone else to use.
This may result in kernel panic while relasing the pinned pages
in p9_release_req_pages().

Also rearranged the while loop in req_done() for better redability.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 16:32:47 -05:00
Venkateswararao Jujjuri (JV)
53bda3e5b4 [net/9p] unconditional wake_up to proc waiting for space on VirtIO ring
Process may wait to get space on VirtIO ring to send a transaction to
VirtFS server. Current code just does a conditional wake_up() which
means only one process will be woken up even if multiple processes
are waiting.

This fix makes the wake_up unconditional. Hence we won't have any
processes waiting for-ever.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 16:32:19 -05:00
Aneesh Kumar K.V
42869c8ada fs/9p: Add v9fs_dentry2v9ses
Add the new static inline and use the same

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:36 -05:00
Aneesh Kumar K.V
7add697a3d fs/9p: Attach writeback_fid on first open with WR flag
We don't need writeback fid if we are only doing O_RDONLY open

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:36 -05:00
Aneesh Kumar K.V
ea59bb759b fs/9p: Open writeback fid in O_SYNC mode
Older version of protocol don't support tsyncfs operation.
So for them force a O_SYNC flag on the server

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:36 -05:00
Aneesh Kumar K.V
059c138bc7 fs/9p: Use truncate_setsize instead of vmtruncate
convert vmtruncate usage to truncate_setsize. We also writeback
all dirty pages before doing 9p operations and on success call truncate_setsize.
This ensure that we continue sanely on failed truncate on the server. The
disadvantage is that we are now going to write back the content that get
thrown away later as a part of truncate.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:35 -05:00
Aneesh Kumar K.V
472e7f9f8b net/9p: Fix compile warning
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:35 -05:00
Aneesh Kumar K.V
eeff66ef6e net/9p: Convert the in the 9p rpc call path to GFP_NOFS
Without this we can cause reclaim allocation in writepage.

[ 3433.448430] =================================
[ 3433.449117] [ INFO: inconsistent lock state ]
[ 3433.449117] 2.6.38-rc5+ #84
[ 3433.449117] ---------------------------------
[ 3433.449117] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-R} usage.
[ 3433.449117] kswapd0/505 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 3433.449117]  (iprune_sem){+++++-}, at: [<ffffffff810ebbab>] shrink_icache_memory+0x45/0x2b1
[ 3433.449117] {RECLAIM_FS-ON-W} state was registered at:
[ 3433.449117]   [<ffffffff8107fe5f>] mark_held_locks+0x52/0x70
[ 3433.449117]   [<ffffffff8107ff02>] lockdep_trace_alloc+0x85/0x9f
[ 3433.449117]   [<ffffffff810d353d>] slab_pre_alloc_hook+0x18/0x3c
[ 3433.449117]   [<ffffffff810d3fd5>] kmem_cache_alloc+0x23/0xa2
[ 3433.449117]   [<ffffffff8127be77>] idr_pre_get+0x2d/0x6f
[ 3433.449117]   [<ffffffff815434eb>] p9_idpool_get+0x30/0xae
[ 3433.449117]   [<ffffffff81540123>] p9_client_rpc+0xd7/0x9b0
[ 3433.449117]   [<ffffffff815427b0>] p9_client_clunk+0x88/0xdb
[ 3433.449117]   [<ffffffff811d56e5>] v9fs_evict_inode+0x3c/0x48
[ 3433.449117]   [<ffffffff810eb511>] evict+0x1f/0x87
[ 3433.449117]   [<ffffffff810eb5c0>] dispose_list+0x47/0xe3
[ 3433.449117]   [<ffffffff810eb8da>] evict_inodes+0x138/0x14f
[ 3433.449117]   [<ffffffff810d90e2>] generic_shutdown_super+0x57/0xe8
[ 3433.449117]   [<ffffffff810d91e8>] kill_anon_super+0x11/0x50
[ 3433.449117]   [<ffffffff811d4951>] v9fs_kill_super+0x49/0xab
[ 3433.449117]   [<ffffffff810d926e>] deactivate_locked_super+0x21/0x46
[ 3433.449117]   [<ffffffff810d9e84>] deactivate_super+0x40/0x44
[ 3433.449117]   [<ffffffff810ef848>] mntput_no_expire+0x100/0x109
[ 3433.449117]   [<ffffffff810f0aeb>] sys_umount+0x2f1/0x31c
[ 3433.449117]   [<ffffffff8102c87b>] system_call_fastpath+0x16/0x1b
[ 3433.449117] irq event stamp: 192941
[ 3433.449117] hardirqs last  enabled at (192941): [<ffffffff81568dcf>] _raw_spin_unlock_irq+0x2b/0x30
[ 3433.449117] hardirqs last disabled at (192940): [<ffffffff810b5f97>] shrink_inactive_list+0x290/0x2f5
[ 3433.449117] softirqs last  enabled at (188470): [<ffffffff8105fd65>] __do_softirq+0x133/0x152
[ 3433.449117] softirqs last disabled at (188455): [<ffffffff8102d7cc>] call_softirq+0x1c/0x28
[ 3433.449117]
[ 3433.449117] other info that might help us debug this:
[ 3433.449117] 1 lock held by kswapd0/505:
[ 3433.449117]  #0:  (shrinker_rwsem){++++..}, at: [<ffffffff810b52e2>] shrink_slab+0x38/0x15f
[ 3433.449117]
[ 3433.449117] stack backtrace:
[ 3433.449117] Pid: 505, comm: kswapd0 Not tainted 2.6.38-rc5+ #84
[ 3433.449117] Call Trace:
[ 3433.449117]  [<ffffffff8107fbce>] ? valid_state+0x17e/0x191
[ 3433.449117]  [<ffffffff81036896>] ? save_stack_trace+0x28/0x45
[ 3433.449117]  [<ffffffff81080426>] ? check_usage_forwards+0x0/0x87
[ 3433.449117]  [<ffffffff8107fcf4>] ? mark_lock+0x113/0x22c
[ 3433.449117]  [<ffffffff8108105f>] ? __lock_acquire+0x37a/0xcf7
[ 3433.449117]  [<ffffffff8107fc0e>] ? mark_lock+0x2d/0x22c
[ 3433.449117]  [<ffffffff81081077>] ? __lock_acquire+0x392/0xcf7
[ 3433.449117]  [<ffffffff810b14d2>] ? determine_dirtyable_memory+0x15/0x28
[ 3433.449117]  [<ffffffff81081a33>] ? lock_acquire+0x57/0x6d
[ 3433.449117]  [<ffffffff810ebbab>] ? shrink_icache_memory+0x45/0x2b1
[ 3433.449117]  [<ffffffff81567d85>] ? down_read+0x47/0x5c
[ 3433.449117]  [<ffffffff810ebbab>] ? shrink_icache_memory+0x45/0x2b1
[ 3433.449117]  [<ffffffff810ebbab>] ? shrink_icache_memory+0x45/0x2b1
[ 3433.449117]  [<ffffffff810b5385>] ? shrink_slab+0xdb/0x15f
[ 3433.449117]  [<ffffffff810b69bc>] ? kswapd+0x574/0x96a
[ 3433.449117]  [<ffffffff810b6448>] ? kswapd+0x0/0x96a
[ 3433.449117]  [<ffffffff810714e2>] ? kthread+0x7d/0x85
[ 3433.449117]  [<ffffffff8102d6d4>] ? kernel_thread_helper+0x4/0x10
[ 3433.449117]  [<ffffffff81569200>] ? restore_args+0x0/0x30
[ 3433.449117]  [<ffffffff81071465>] ? kthread+0x0/0x85
[ 3433.449117]  [<ffffffff8102d6d0>] ? kernel_thread_helper+0x0/0x10

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:35 -05:00
Aneesh Kumar K.V
5a7e0a8cf5 fs/9p: Fix race in initializing writeback fid
When two process open the same file we can end up with both of them
allocating the writeback_fid. Add a new mutex which can be used
for synchronizing v9fs_inode member values.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2011-03-22 15:43:35 -05:00
Christoph Lameter
4fdccdfbb4 slub: Add statistics for this_cmpxchg_double failures
Add some statistics for debugging.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-03-22 20:48:04 +02:00
Christoph Lameter
2fd66c517d slub: Add missing irq restore for the OOM path
OOM path is missing the irq restore in the CONFIG_CMPXCHG_LOCAL case.

Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-03-22 20:48:04 +02:00
Yehuda Sadeh
59c2be1e4d rbd: use watch/notify for changes in rbd header
Send notifications when we change the rbd header (e.g. create a snapshot)
and wait for such notifications.  This allows synchronizing the snapshot
creation between different rbd clients/rools.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2011-03-22 11:33:56 -07:00
Yehuda Sadeh
a40c4f10e3 libceph: add lingering request and watch/notify event framework
Lingering requests are requests that are sent to the OSD normally but
tracked also after we get a successful request.  This keeps the OSD
connection open and resends the original request if the object moves to
another OSD.  The OSD can then send notification messages back to us
if another client initiates a notify.

This framework will be used by RBD so that the client gets notification
when a snapshot is created by another node or tool.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2011-03-22 11:33:55 -07:00
Linus Torvalds
f741a79e98 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: make fuse_dentry_revalidate() RCU aware
  fuse: make fuse_permission() RCU aware
  fuse: wakeup pollers on connection release/abort
  fuse: reduce size of struct fuse_request
2011-03-22 10:42:43 -07:00
Linus Torvalds
73d5a8675f Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  xen: update mask_rw_pte after kernel page tables init changes
  xen: set max_pfn_mapped to the last pfn mapped
  x86: Cleanup highmap after brk is concluded

Fix up trivial onflict (added header file includes) in
arch/x86/mm/init_64.c
2011-03-22 10:41:36 -07:00
Linus Torvalds
e77277dfe2 Merge branch 'next-samsung' of git://git.fluff.org/bjdooks/linux
* 'next-samsung' of git://git.fluff.org/bjdooks/linux:
  ARM: H1940/RX1950: Change default LED triggers
  ARM: S3C2442: RX1950: Add support for LED blinking
  ARM: S3C2442: RX1950: Retain LEDs state in suspend
  ARM: S3C2410: H1940: Fix lcd_power_set function
  ARM: S3C2410: H1940: Add battery support
  ARM: S3C2410: H1940: Use leds-gpio driver for LEDs managing
  ARM: S3C2410: H1940: Make h1940-bluetooth.c compile again
  ARM: S3C2410: H1940: Add keys device
2011-03-22 10:06:54 -07:00
Linus Torvalds
75ea6358bc Merge branch 'for-linus/2639/i2c-2' of git://git.fluff.org/bjdooks/linux
* 'for-linus/2639/i2c-2' of git://git.fluff.org/bjdooks/linux:
  i2c-pxa2xx: Don't clear isr bits too early
  i2c-pxa2xx: Fix register offsets
  i2c-pxa2xx: pass of_node from platform driver to adapter and publish
  i2c-pxa2xx: check timeout correctly
  i2c-pxa2xx: add support for shared IRQ handler
  i2c-pxa2xx: Add PCI support for PXA I2C controller
  ARM: pxa2xx: reorganize I2C files
  i2c-pxa2xx: use dynamic register layout
  i2c-mxs: set controller to pio queue mode after reset
  i2c-eg20t: support new device OKI SEMICONDUCTOR ML7213 IOH
  i2c/busses: Add support for Diolan U2C-12 USB-I2C adapter
2011-03-22 10:05:27 -07:00
Linus Torvalds
14577beb82 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: Dont define useless label in the !CONFIG_CMPXCHG_LOCAL case
  slab,rcu: don't assume the size of struct rcu_head
  slub,rcu: don't assume the size of struct rcu_head
  slub: automatically reserve bytes at the end of slab
  Lockless (and preemptless) fastpaths for slub
  slub: Get rid of slab_free_hook_irq()
  slub: min_partial needs to be in first cacheline
  slub: fix ksize() build error
  slub: fix kmemcheck calls to match ksize() hints
  Revert "slab: Fix missing DEBUG_SLAB last user"
  mm: Remove support for kmem_cache_name()
2011-03-22 09:36:23 -07:00
Martin K. Petersen
09b9cc44c9 sd: Fail discard requests when logical block provisioning has been disabled
Ensure that we kill discard requests after logical block provisioning
has been disabled in sysfs.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 09:35:53 -07:00
Linus Torvalds
c62b389863 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (33 commits)
  IPVS: Use global mutex in ip_vs_app.c
  ipvs: fix a typo in __ip_vs_control_init()
  veth: Fix the byte counters
  net ipv6: Fix duplicate /proc/sys/net/ipv6/neigh directory entries.
  macvlan: Fix use after free of struct macvlan_port.
  net: fix incorrect spelling in drop monitor protocol
  can: c_can: Do basic c_can configuration _before_ enabling the interrupts
  net/appletalk: fix atalk_release use after free
  ipx: fix ipx_release()
  snmp: SNMP_UPD_PO_STATS_BH() always called from softirq
  l2tp: fix possible oops on l2tp_eth module unload
  xfrm: Fix initialize repl field of struct xfrm_state
  netfilter: ipt_CLUSTERIP: fix buffer overflow
  netfilter: xtables: fix reentrancy
  netfilter: ipset: fix checking the type revision at create command
  netfilter: ipset: fix address ranges at hash:*port* types
  niu: Rename NIU parent platform device name to fix conflict.
  r8169: fix a bug in rtl8169_init_phy()
  bonding: fix a typo in a comment
  ftmac100: use resource_size()
  ...
2011-03-22 09:25:34 -07:00