Commit Graph

154 Commits

Author SHA1 Message Date
Al Viro
f80aabb03a [PATCH] gfp_t: dma-mapping (amd64)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:48 -07:00
Al Viro
06a544971f [PATCH] gfp_t: dma-mapping (ia64)
... and related annotations for amd64 - swiotlb code is shared, but
prototypes are not.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:47 -07:00
Linus Torvalds
79b95a454b Revert "x86-64: Avoid unnecessary double bouncing for swiotlb"
Commit id 6142891a0c

Andi Kleen reports that it seems to break things for some people,
and since it's purely a small optimization, revert it for now.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-27 16:28:39 -07:00
Andi Kleen
421c7ce6d0 [PATCH] x86_64: Allocate cpu local data for all possible CPUs
CPU hotplug fills up the possible map to NR_CPUs, but it did that after
setting up per CPU data. This lead to CPU data not getting allocated
for all possible CPUs, which lead to various side effects.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-10 16:33:25 -07:00
Kirill Korotaev
1294b118cb [PATCH] x86_64: Add missing () around arguments of pte_index macro
x86-64: Add missing () around arguments of pte_index macro

Signed-Off-By: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 08:54:38 -07:00
Andi Kleen
7d318d7747 [PATCH] Fix up TLB flush filter disabling
I checked with AMD and they requested to only disable it for family 15.
Also disable it for i386 too. And some style fixes.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-29 15:41:42 -07:00
Andrew Morton
73a0b538ee [PATCH] x86_64: desc.h-needs smp.h
include/asm/desc.h: In function `load_LDT':
include/asm/desc.h:209: warning: implicit declaration of function `get_cpu'
include/asm/desc.h:211: warning: implicit declaration of function `put_cpu'

Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:01 -07:00
Randy Dunlap
33bf56106d [PATCH] feature removal of io_remap_page_range()
As written in Documentation/feature-removal-schedule.txt, remove the
io_remap_page_range() kernel API.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-13 08:22:33 -07:00
Andi Kleen
2ade814736 [PATCH] x86-64: clean up local_add/sub arguments
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:59 -07:00
Chuck Ebbert
66759a01ad [PATCH] x86-64: i386/x86-64: Fix time going twice as fast problem on ATI Xpress chipsets
Original patch from Bertro Simul

This is probably still not quite correct, but seems to be
the best solution so far.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:58 -07:00
Jan Beulich
049cdefe19 [PATCH] x86-64: reduce x86-64 bug frame by 4 bytes
As mentioned before, the size of the bug frame can be further reduced while
continuing to use instructions to encode the information.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:58 -07:00
Jan Beulich
a2d236b3ac [PATCH] x86-64: Lose constraints on cmpxchg
While only cosmetic for x86-64, this adjusts the cmpxchg code appearantly
inherited from i386 to use more generic constraints.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:57 -07:00
Jan Beulich
1a426cb764 [PATCH] x86-64: Declare NMI_VECTOR and handle it in the IPI sending code.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:57 -07:00
Andi Kleen
a2a0c992e9 [PATCH] x86-64: Remove unused vxtime.hz field
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:57 -07:00
Andi Kleen
a0d58c9741 [PATCH] x86-64: Set the stack pointer correctly in init_thread and init_tss
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:57 -07:00
Jan Beulich
1209140c3c [PATCH] x86-64: Safe interrupts in oops_begin/end
Rather than blindly re-enabling interrupts in oops_end(), save their state
in oope_begin() and then restore that state.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:57 -07:00
Andi Kleen
059bf0f6c3 [PATCH] x86-64: Merge msr.c with i386 version
The only difference was the inline assembly, so move that into
asm/msr.h and merge with the i386 version.

This adds some missing sysfs support code to x86-64.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:57 -07:00
Jan Beulich
7effaa882a [PATCH] x86-64: Fix CFI information
Being the foundation for reliable stack unwinding, this fixes CFI unwind
annotations in many low-level x86_64 routines, plus a config option
(available to all architectures, and also present in the previously sent
patch adding such annotations to i386 code) to enable them separatly
rather than only along with adding full debug information.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:56 -07:00
Andi Kleen
27183ebd33 [PATCH] x86-64: Add dma_sync_single_range_for_{cpu,device}
Currently just defined to their non range parts.

Pointed out by John Linville

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:56 -07:00
Adrian Bunk
9c0aa0f9a1 [PATCH] Replace extern inline with static inline in asm-x86_64/*
They should be identical in the kernel now, but this
makes it consistent with other code.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:56 -07:00
Nakul Saraiya
f297e4e5e4 [PATCH] Increase nodemap hash.
Needed for some newer Opteron systems with E stepping and memory
relocation enabled. The node addresses are different in lower
bits now so the nodemap hash function needs to be enlarged.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:55 -07:00
Jim Paradis
fb048927ad [PATCH] x86-64: Fix off by one in pfn_valid
When I gave proposed the fix to pfn_valid() for RHEL4, Stephen Tweedie's
sharp eyes caught this:

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:55 -07:00
Andi Kleen
2b4a08150e [PATCH] x86-64: Increase TLB flush array size
The generic TLB flush functions kept upto 506 pages per
CPU to avoid too frequent IPIs.

This value was done for the L1 cache of older x86 CPUs,
but with modern CPUs it does not make much sense anymore.
TLB flushing is slow enough that using the L2 cache is fine.

This patch increases the flush array on x86-64 to cache
5350 pages. That is roughly 20MB with 4K pages. It speeds
up large munmaps in multithreaded processes on SMP considerably.

The cost is roughly 42k of memory per CPU, which is reasonable.

I only increased it on x86-64 for now, but it would probably
make sense to increase it everywhere. Embedded architectures
with SMP may keep it smaller to save some memory per CPU.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:58 -07:00
Andi Kleen
165aeb8284 [PATCH] x86-64: Don't include config.h in asm/timex.h
asm-x86-64/timex.h does not reference CONFIG constants.
Do not need to include config.h.

Signed-off-by: Grant Grundler <iod00d@hp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:58 -07:00
Andi Kleen
3f74478b5f [PATCH] x86-64: Some cleanup and optimization to the processor data area.
- Remove unused irqrsp field
- Remove pda->me
- Optimize set_softirq_pending slightly

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:58 -07:00
Andi Kleen
e5bc8b6baf [PATCH] x86-64: Make remote TLB flush more scalable
Instead of using a global spinlock to protect the state
of the remote TLB flush use a lock and state for each sending CPU.

To tell the receiver where to look for the state use 8 different
call vectors.  Each CPU uses a specific vector to trigger flushes on other
CPUs. Depending on the received vector the target CPUs look into
the right per cpu variable for the flush data.

When the system has more than 8 CPUs they are hashed to the 8 available
vectors. The limited global vector space forces us to this right now.
In future when interrupts are split into per CPU domains this could be
fixed, at the cost of needing more IPIs in flat mode.

Also some minor cleanup in the smp flush code and remove some outdated
debug code.

Requires patch to move cpu_possible_map setup earlier.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:58 -07:00
Andi Kleen
69e1a33f62 [PATCH] x86-64: Use ACPI PXM to parse PCI<->node assignments
Since this is shared code I had to implement it for i386 too

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:57 -07:00
Andi Kleen
b9aac10ddd [PATCH] x86-64: Remove redundant max_mapnr and replace with end_pfn
The FLATMEM people added it, but there doesn't seem a good reason
because end_pfn is identical.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:57 -07:00
Andi Kleen
6142891a0c [PATCH] x86-64: Avoid unnecessary double bouncing for swiotlb
PCI_DMA_BUS_IS_PHYS has to be zero even when the GART IOMMU is disabled
and the swiotlb is used. Otherwise the block layer does unnecessary
double bouncing.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:56 -07:00
Andi Kleen
3f098c2605 [PATCH] x86-64: Support dualcore and 8 socket systems in k8 fallback node parsing
In particular on systems where the local APIC space and node space
is very different from the Linux CPU number space.

Previously the older NUMA setup code directly parsing the K8
northbridge registers had some issues on 8 socket or dual core
systems. This patch fixes them.

This is mainly done by fixing some confusion between Linux
CPU numbers and local APIC ids. We now pass the local APIC IDs
to later code, which avoids mismatches.

Also add some heuristics to detect cases where the Hypertransport
nodeids and the local APIC IDs don't match, but are shifted
by a constant offset.

This is still all quite hackish, hopefully BIOS writers fill
in correct SRATs instead.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:56 -07:00
Andi Kleen
b91691164b [PATCH] x86-64: Don't cache align PDA on UP builds
Suggested by someone I forgot who sorry.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:56 -07:00
Andi Kleen
0b07e984fc [PATCH] x86-64: Don't assign CPU numbers in SRAT parsing
Do that later when the CPU boots. SRAT just stores the APIC<->Node
mapping node. This fixes problems on systems where the order
of SRAT entries does not match the MADT.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:55 -07:00
Andi Kleen
61c11341ed [PATCH] x86-64: Remove esr disable hack in APIC code
This was just needed for the Numasaurus, which fortunately
doesn't support x86-64 CPUs.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:55 -07:00
Andi Kleen
eddfb4ed29 [PATCH] x86-64: Remove obsolete APIC "write around" bug workaround
No x86-64 chipset has this bug

Generated code doesn't change because it was always disabled.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:49:55 -07:00
Adrian Bunk
672289e9fa [PATCH] i386/x86_64: make get_cpu_vendor() static
get_cpu_vendor() no longer has any users in other files.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 10:06:35 -07:00
Ingo Molnar
fb1c8f93d8 [PATCH] spinlock consolidation
This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code.  It does the following
things:

 - consolidates and enhances the spinlock/rwlock debugging code

 - simplifies the asm/spinlock.h files

 - encapsulates the raw spinlock type and moves generic spinlock
   features (such as ->break_lock) into the generic code.

 - cleans up the spinlock code hierarchy to get rid of the spaghetti.

Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c.  (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)

Also, i've enhanced the rwlock debugging facility, it will now track
write-owners.  There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.

The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:

 include/asm-i386/spinlock_types.h       |   16
 include/asm-x86_64/spinlock_types.h     |   16

I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:

   SMP                         |  UP
   ----------------------------|-----------------------------------
   asm/spinlock_types_smp.h    |  linux/spinlock_types_up.h
   linux/spinlock_types.h      |  linux/spinlock_types.h
   asm/spinlock_smp.h          |  linux/spinlock_up.h
   linux/spinlock_api_smp.h    |  linux/spinlock_api_up.h
   linux/spinlock.h            |  linux/spinlock.h

/*
 * here's the role of the various spinlock/rwlock related include files:
 *
 * on SMP builds:
 *
 *  asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
 *                        initializers
 *
 *  linux/spinlock_types.h:
 *                        defines the generic type and initializers
 *
 *  asm/spinlock.h:       contains the __raw_spin_*()/etc. lowlevel
 *                        implementations, mostly inline assembly code
 *
 *   (also included on UP-debug builds:)
 *
 *  linux/spinlock_api_smp.h:
 *                        contains the prototypes for the _spin_*() APIs.
 *
 *  linux/spinlock.h:     builds the final spin_*() APIs.
 *
 * on UP builds:
 *
 *  linux/spinlock_type_up.h:
 *                        contains the generic, simplified UP spinlock type.
 *                        (which is an empty structure on non-debug builds)
 *
 *  linux/spinlock_types.h:
 *                        defines the generic type and initializers
 *
 *  linux/spinlock_up.h:
 *                        contains the __raw_spin_*()/etc. version of UP
 *                        builds. (which are NOPs on non-debug, non-preempt
 *                        builds)
 *
 *   (included on UP-non-debug builds:)
 *
 *  linux/spinlock_api_up.h:
 *                        builds the _spin_*() APIs.
 *
 *  linux/spinlock.h:     builds the final spin_*() APIs.
 */

All SMP and UP architectures are converted by this patch.

arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers.  m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.

From: Grant Grundler <grundler@parisc-linux.org>

  Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
  Builds 32-bit SMP kernel (not booted or tested).  I did not try to build
  non-SMP kernels.  That should be trivial to fix up later if necessary.

  I converted bit ops atomic_hash lock to raw_spinlock_t.  Doing so avoids
  some ugly nesting of linux/*.h and asm/*.h files.  Those particular locks
  are well tested and contained entirely inside arch specific code.  I do NOT
  expect any new issues to arise with them.

 If someone does ever need to use debug/metrics with them, then they will
  need to unravel this hairball between spinlocks, atomic ops, and bit ops
  that exist only because parisc has exactly one atomic instruction: LDCW
  (load and clear word).

From: "Luck, Tony" <tony.luck@intel.com>

   ia64 fix

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 10:06:21 -07:00
Linus Torvalds
486a153f0e Merge master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild 2005-09-09 15:46:49 -07:00
Kenji Kaneshige
24b20ac6e1 [PATCH] remove unnecessary handle_IRQ_event() prototypes
The function prototype for handle_IRQ_event() in a few architctures is not
needed because they use GENERIC_HARDIRQ.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:57:33 -07:00
Sam Ravnborg
e2d5df935d kbuild: alpha,x86_64 use generic asm-offsets.h support
Delete obsolete stuff from arch makefiles
Rename .h file to asm-offsets.h

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2005-09-09 21:28:48 +02:00
Len Brown
64e47488c9 Merge linux-2.6 with linux-acpi-2.6 2005-09-08 01:45:47 -04:00
Stephen Rothwell
5ac353f9ba [PATCH] Clean up struct flock definitions
This patch just gathers together all the struct flock definitions except
xtensa into asm-generic/fcntl.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
1abf62afb6 [PATCH] Clean up the fcntl operations
This patch puts the most popular of each fcntl operation/flag into
asm-generic/fcntl.h and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
e64ca97fd8 [PATCH] Clean up the open flags
This patch puts the most popular of each open flag into asm-generic/fcntl.h
and cleans up the arch files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:38 -07:00
Stephen Rothwell
9317259ead [PATCH] Create asm-generic/fcntl.h
This set of patches creates asm-generic/fcntl.h and consolidates as much as
possible from the asm-*/fcntl.h files into it.

This patch just gathers all the identical bits of the asm-*/fcntl.h files into
asm-generic/fcntl.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:37 -07:00
Jesper Juhl
97de50c0ad [PATCH] remove verify_area(): remove verify_area() from various uaccess.h headers
Remove the deprecated (and unused) verify_area() from various uaccess.h
headers.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:35 -07:00
Christoph Hellwig
c8d127418d [PATCH] remove asm-*/hdreg.h
unused and useless..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:30 -07:00
H. J. Lu
36d57ac4a8 [PATCH] auxiliary vector cleanups
The size of auxiliary vector is fixed at 42 in linux/sched.h.  But it isn't
very obvious when looking at linux/elf.h.  This patch adds AT_VECTOR_SIZE
so that we can change it if necessary when a new vector is added.

Because of include file ordering problems, doing this necessitated the
extraction of the AT_* symbols into a standalone header file.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:21 -07:00
Stephen Rothwell
202e5979af [PATCH] compat: be more consistent about [ug]id_t
When I first wrote the compat layer patches, I was somewhat cavalier about
the definition of compat_uid_t and compat_gid_t (or maybe I just
misunderstood :-)).  This patch makes the compat types much more consistent
with the types we are being compatible with and hopefully will fix a few
bugs along the way.

	compat type		type in compat arch
	__compat_[ug]id_t	__kernel_[ug]id_t
	__compat_[ug]id32_t	__kernel_[ug]id32_t
	compat_[ug]id_t		[ug]id_t

The difference is that compat_uid_t is always 32 bits (for the archs we
care about) but __compat_uid_t may be 16 bits on some.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:19 -07:00
Jakub Jelinek
4732efbeb9 [PATCH] FUTEX_WAKE_OP: pthread_cond_signal() speedup
ATM pthread_cond_signal is unnecessarily slow, because it wakes one waiter
(which at least on UP usually means an immediate context switch to one of
the waiter threads).  This waiter wakes up and after a few instructions it
attempts to acquire the cv internal lock, but that lock is still held by
the thread calling pthread_cond_signal.  So it goes to sleep and eventually
the signalling thread is scheduled in, unlocks the internal lock and wakes
the waiter again.

Now, before 2003-09-21 NPTL was using FUTEX_REQUEUE in pthread_cond_signal
to avoid this performance issue, but it was removed when locks were
redesigned to the 3 state scheme (unlocked, locked uncontended, locked
contended).

Following scenario shows why simply using FUTEX_REQUEUE in
pthread_cond_signal together with using lll_mutex_unlock_force in place of
lll_mutex_unlock is not enough and probably why it has been disabled at
that time:

The number is value in cv->__data.__lock.
        thr1            thr2            thr3
0       pthread_cond_wait
1       lll_mutex_lock (cv->__data.__lock)
0       lll_mutex_unlock (cv->__data.__lock)
0       lll_futex_wait (&cv->__data.__futex, futexval)
0                       pthread_cond_signal
1                       lll_mutex_lock (cv->__data.__lock)
1                                       pthread_cond_signal
2                                       lll_mutex_lock (cv->__data.__lock)
2                                         lll_futex_wait (&cv->__data.__lock, 2)
2                       lll_futex_requeue (&cv->__data.__futex, 0, 1, &cv->__data.__lock)
                          # FUTEX_REQUEUE, not FUTEX_CMP_REQUEUE
2                       lll_mutex_unlock_force (cv->__data.__lock)
0                         cv->__data.__lock = 0
0                         lll_futex_wake (&cv->__data.__lock, 1)
1       lll_mutex_lock (cv->__data.__lock)
0       lll_mutex_unlock (cv->__data.__lock)
          # Here, lll_mutex_unlock doesn't know there are threads waiting
          # on the internal cv's lock

Now, I believe it is possible to use FUTEX_REQUEUE in pthread_cond_signal,
but it will cost us not one, but 2 extra syscalls and, what's worse, one of
these extra syscalls will be done for every single waiting loop in
pthread_cond_*wait.

We would need to use lll_mutex_unlock_force in pthread_cond_signal after
requeue and lll_mutex_cond_lock in pthread_cond_*wait after lll_futex_wait.

Another alternative is to do the unlocking pthread_cond_signal needs to do
(the lock can't be unlocked before lll_futex_wake, as that is racy) in the
kernel.

I have implemented both variants, futex-requeue-glibc.patch is the first
one and futex-wake_op{,-glibc}.patch is the unlocking inside of the kernel.
 The kernel interface allows userland to specify how exactly an unlocking
operation should look like (some atomic arithmetic operation with optional
constant argument and comparison of the previous futex value with another
constant).

It has been implemented just for ppc*, x86_64 and i?86, for other
architectures I'm including just a stub header which can be used as a
starting point by maintainers to write support for their arches and ATM
will just return -ENOSYS for FUTEX_WAKE_OP.  The requeue patch has been
(lightly) tested just on x86_64, the wake_op patch on ppc64 kernel running
32-bit and 64-bit NPTL and x86_64 kernel running 32-bit and 64-bit NPTL.

With the following benchmark on UP x86-64 I get:

for i in nptl-orig nptl-requeue nptl-wake_op; do echo time elf/ld.so --library-path .:$i /tmp/bench; \
for j in 1 2; do echo ( time elf/ld.so --library-path .:$i /tmp/bench ) 2>&1; done; done
time elf/ld.so --library-path .:nptl-orig /tmp/bench
real 0m0.655s user 0m0.253s sys 0m0.403s
real 0m0.657s user 0m0.269s sys 0m0.388s
time elf/ld.so --library-path .:nptl-requeue /tmp/bench
real 0m0.496s user 0m0.225s sys 0m0.271s
real 0m0.531s user 0m0.242s sys 0m0.288s
time elf/ld.so --library-path .:nptl-wake_op /tmp/bench
real 0m0.380s user 0m0.176s sys 0m0.204s
real 0m0.382s user 0m0.175s sys 0m0.207s

The benchmark is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00001.txt
Older futex-requeue-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00002.txt
Older futex-wake_op-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00003.txt
Will post a new version (just x86-64 fixes so that the patch
applies against pthread_cond_signal.S) to libc-hacker ml soon.

Attached is the kernel FUTEX_WAKE_OP patch as well as a simple-minded
testcase that will not test the atomicity of the operation, but at least
check if the threads that should have been woken up are woken up and
whether the arithmetic operation in the kernel gave the expected results.

Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Jamie Lokier <jamie@shareable.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:17 -07:00
Eric Dumazet
19aaabb584 [PATCH] x86_64: prefetchw() can fall back to prefetch() if !3DNOW
This is a multi-part message in MIME format.  If the cpu lacks 3DNOW
feature, we can use a normal prefetcht0 instruction instead of NOP5.
"prefetchw (%rxx)" and "prefetcht0 (%rxx)" have the same length, ranging
from 3 to 5 bytes depending on the register.  So this patch even helps
AMD64, shortening the length of the code.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:15 -07:00