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2006-06-26[PATCH] x86_64: Fix race in cpu_local_* on preemptible kernelsAndi Kleen
When a process changes CPUs while doing the non atomic cpu_local_* operations it might operate on the local_t of a different CPUs. Fix that by disabling preemption. Pointed out by Christopher Lameter Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] i386/x86-64/ia64: Move polling flag into thread_info_statusAndi Kleen
During some profiling I noticed that default_idle causes a lot of memory traffic. I think that is caused by the atomic operations to clear/set the polling flag in thread_info. There is actually no reason to make this atomic - only the idle thread does it to itself, other CPUs only read it. So I moved it into ti->status. Converted i386/x86-64/ia64 for now because that was the easiest way to fix ACPI which also manipulates these flags in its idle function. Cc: Nick Piggin <npiggin@novell.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Len Brown <len.brown@intel.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: mce_amd support for family 0x10 processorsJacob Shin
Add support for mce threshold registers found in future AMD family 0x10 processors. Backwards compatible with family 0xF hardware. AK: fixed build on !SMP Signed-off-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: mce_amd relocate sysfs filesJacob Shin
Get rid of /sys/devices/system/threshold directory and move mce_amd thresholding files into the machine sysfs directory -- /sys/devices/system/machinecheck. AK: Fixed warning Signed-off-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: apic support for extended apic interruptJacob Shin
Add support for extended APIC LVT found in future AMD processors. Signed-off-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Add X86_FEATURE_RDTSCP, fix rdtscp in /proc/cpuinfoVojtech Pavlik
This patch adds the X86_FEATURE_RDTSCP #define, so that kernel code can check for the feature easily and also fixes the location of the "rdtscp" string in the cpuinfo tables. Signed-off-by: Vojtech Pavlik <vojtech@suse.cz> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Rename oem_force_hpet_timer to apic_is_clustered_boxVojtech Pavlik
Rename oem_force_hpet_timer to apic_is_clustered_box, to give the function a better fitting name - it really isn't at all about HPET. Signed-off-by: Vojtech Pavlik <vojtech@suse.cz> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Add useful constants to time.hVojtech Pavlik
In timekeeping code, one often does need to use conversion constants. Naming these leads to code that's easier to understand, showing the reader between which units the conversion is made. Signed-off-by: Vojtech Pavlik <vojtech@suse.cz> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: moving phys_proc_id and cpu_core_id to cpuinfo_x86Rohit Seth
Most of the fields of cpuinfo are defined in cpuinfo_x86 structure. This patch moves the phys_proc_id and cpu_core_id for each processor to cpuinfo_x86 structure as well. Signed-off-by: Rohit Seth <rohitseth@google.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Calgary IOMMU - Calgary specific bitsJon Mason
This patch hooks Calgary into the build, the x86-64 IOMMU initialization paths, and introduces the Calgary specific bits. The implementation draws inspiration from both PPC (which has support for the same chip but requires firmware support which we don't have on x86-64) and gart. Calgary is different from gart in that it support a translation table per PHB, as opposed to the single gart aperture. Changes from previous version: * Addition of boot-time disablement for bus-level translation/isolation (e.g, enable userspace DMA for things like X) * Usage of newer IOMMU abstraction functions Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com> Signed-off-by: Jon Mason <jdmason@us.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Calgary IOMMU - IOMMU abstractionsJon Mason
This patch creates a new interface for IOMMUs by adding a centralized location for IOMMU allocation (for translation tables/apertures) and IOMMU initialization. In creating these, code was moved around for abstraction, uniformity, and consiceness. Take note of the move of the iommu_setup bootarg parsing code to __setup. This is enabled by moving back the location of the aperture allocation/detection to mem init (which while ugly, was already the location of the swiotlb_init). While a slight departure from the previous patch, I belive this provides the true intention of the previous versions of the patch which changed this code. It also makes the addition of the upcoming calgary code much cleaner than previous patches. [AK: Removed one broken change. iommu_setup still has to be called early] Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com> Signed-off-by: Jon Mason <jdmason@us.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Calgary IOMMU - move valid_dma_direction into the callersJon Mason
Based on Andi Kleen's comments on the original Calgary patch, move valid_dma_direction into the calling functions. Signed-off-by: Muli Ben-Yehuda <muli@il.ibm.com> Signed-off-by: Jon Mason <jdmason@us.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Calgary IOMMU - introduce iommu_detectedJon Mason
swiotlb relies on the gart specific iommu_aperture variable to know if we discovered a hardware IOMMU before swiotlb initialization. Introduce iommu_detected to do the same thing, but in a HW IOMMU neutral manner, in preparation for adding the Calgary HW IOMMU. Signed-Off-By: Muli Ben-Yehuda <muli@il.ibm.com> Signed-Off-By: Jon Mason <jdmason@us.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Get rid of pud_offset_k / __pud_offset_kAndi Kleen
pud_offset_k() equivalent to pud_offset() now. Pointed out by Jan Beulich Similar for __pud_offset_ok, which needs a small change in the callers. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: allow unwinder to build without module supportJan Beulich
Add proper conditionals to be able to build with CONFIG_MODULES=n. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] i386/x86-64: fall back to old-style call trace if no unwindingJan Beulich
If no unwinding is possible at all for a certain exception instance, fall back to the old style call trace instead of not showing any trace at all. Also, allow setting the stack trace mode at the command line. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] i386: reliable stack trace support i386 entry.SJan Beulich
To increase the usefulness of reliable stack unwinding, this adds CFI unwind annotations to many low-level i386 routines. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] i386: reliable stack trace support (i386)Jan Beulich
These are the i386-specific pieces to enable reliable stack traces. This is going to be even more useful once CFI annotations get added to he assembly code, namely to entry.S. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: reliable stack trace support (x86-64)Jan Beulich
These are the x86_64-specific pieces to enable reliable stack traces. The only restriction with this is that it currently cannot unwind across the interrupt->normal stack boundary, as that transition is lacking proper annotation. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: reliable stack trace supportJan Beulich
These are the generic bits needed to enable reliable stack traces based on Dwarf2-like (.eh_frame) unwind information. Subsequent patches will enable x86-64 and i386 to make use of this. Thanks to Andi Kleen and Ingo Molnar, who pointed out several possibilities for improvement. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Rename IOMMU option, fix help and mark option embedded.Andi Kleen
- Rename the GART_IOMMU option to IOMMU to make clear it's not just for AMD - Rewrite the help text to better emphatise this fact - Make it an embedded option because too many people get it wrong. To my astonishment I discovered the aacraid driver tests this symbol directly. This looks quite broken to me - it's an internal implementation detail of the PCI DMA API. Can the maintainer please clarify what this test was intended to do? Cc: linux-scsi@vger.kernel.org Cc: alan@redhat.com Cc: markh@osdl.org Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: remove unused gart header fileJon Mason
include/asm-x86_64/gart-mapping.h is only ever used in arch/x86_64/kernel/setup.c and none of its contents are referenced. Looks to be leftover cruft not removed in the dma_ops patch. Signed-off-by: Jon Mason <jdmason@us.ibm.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Optimize bitmap_weight for small bitmapsAndi Kleen
Use inline code bitmaps <= BITS_PER_LONG in bitmap_weight. This gives _much_ better code. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Remove long obsolete CVSAndi Kleen
Early development of x86-64 Linux was in CVS, but that hasn't been the case for a long time now. Remove the obsolete $Id$s. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: nmi watchdog header cleanupDon Zickus
Misc header cleanup for nmi watchdog. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Add compat_printk and sysctl to turn off compat layer warningsAndi Kleen
Sometimes e.g. with crashme the compat layer warnings can be noisy. Add a way to turn them off by gating all output through compat_printk that checks a global sysctl. The default is not changed. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Clean and enhance up K8 northbridge access codeAndi Kleen
- Factor out the duplicated access/cache code into a single file * Shared between i386/x86-64. - Share flush code between AGP and IOMMU * Fix a bug: AGP didn't wait for end of flush before - Drop 8 northbridges limit and allocate dynamically - Add lock to serialize AGP and IOMMU GART flushes - Add PCI ID for next AMD northbridge - Random related cleanups The old K8 NUMA discovery code is unchanged. New systems should all use SRAT for this. Cc: "Navin Boppuri" <navin.boppuri@newisys.com> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Remove bogus comment in topology.hAndi Kleen
Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Remove most of ia32_unistd.hAndi Kleen
It's only needed for three system calls, no need to maintain a full list forever. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: x86_64 version of the smp alternative patch.Gerd Hoffmann
Changes are largely identical to the i386 version: * alternative #define are moved to the new alternative.h file. * one new elf section with pointers to the lock prefixes which can be nop'ed out for non-smp. * two new elf sections simliar to the "classic" alternatives to replace SMP code with simpler UP code. * fixup headers to use alternative.h instead of defining their own LOCK / LOCK_PREFIX macros. The patch reuses the i386 version of the alternatives code to avoid code duplication. The code in alternatives.c was shuffled around a bit to reduce the number of #ifdefs needed. It also got some tweaks needed for x86_64 (vsyscall page handling) and new features (noreplacement option which was x86_64 only up to now). Debug printk's are changed from compile-time to runtime. Loosely based on a early version from Bastian Blank <waldi@debian.org> Signed-off-by: Gerd Hoffmann <kraxel@suse.de> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] i386/x86-64: Emulate CPUID4 on AMDAndi Kleen
Intel systems report the cache level data from CPUID 4 in sysfs. Add a CPUID 4 emulation for AMD CPUs to report the same information for them. This allows programs to read this information in a uniform way. The AMD way to report this is less flexible so some assumptions are hardcoded (e.g. no L3) Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] x86_64: Use __always_inline for __inline_memcpyAndi Kleen
Inspired from i386 changes Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: make enable_irq() macro statementGreg Ungerer
Change enable_irq() macro to be a statement, not expression. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: fix ColdFire 5249 PLL setGreg Ungerer
Fix PLL setting for the Coldfire 5249 CPU. This brings it into line with the new style frequency configuration of m68knommu parts. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: ColdFire cache flush fixupsGreg Ungerer
Fix flush code for the ColdFire 5206/5206e/5272 cases. Add support for the new ColdFire 532x CPU family Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: force stack alignment on ColdFireGreg Ungerer
This patch solve a bug triggered by execvp (this function use calloc to store the argument list and gcc 3.4.x align the stack to word, not to dword). This situation aren't related to signal handling and all 2.6.x have the bug. On ColdFire targets we must force the stack to be aligned. Original patch from Andrea Tarani <andrea.tarani@gilbarco.com>, Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: configurable frequency selection headerGreg Ungerer
Remove list of fixed clock frequency options used for configuring master clock, and make field an int. Much more flexible this way, no need to add more options for every new used freqency. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25Revert "swsusp special saveable pages support" commitsLinus Torvalds
This reverts commits 3e3318dee0878d42ed62a19c292a2ac284135db3 [PATCH] swsusp: x86_64 mark special saveable/unsaveable pages b6370d96e09944c6e3ae8d5743ca8a8ab1f79f6c [PATCH] swsusp: i386 mark special saveable/unsaveable pages ce4ab0012b32c1a4a1d6e934aeb73bf3151c48d9 [PATCH] swsusp: add architecture special saveable pages support because not only do they apparently cause page faults on x86, the infrastructure doesn't compile on powerpc. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: add ColdFire 532x UART address supportGreg Ungerer
Add support for the UART addressing on the new Freescale M532x CPU family. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: include ColdFire 532x register definitionsGreg Ungerer
Include the ColdFire 532x support when including ColdFire peripharp support definitions. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: add ColdFire 532x cache initGreg Ungerer
Add cache init support for the new ColdFire 532x CPU family. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: ColdFire 532x register definitionsGreg Ungerer
Register definitions for the new Freescale 532x Coldfire CPU family. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: read/write register access for PIT timerGreg Ungerer
Modify the m68knommu/ColdFire PIT timer code to use register offsets with raw_read/raw_write access, instead of a mapped struct. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] m68knommu: read/write register access for ColdFire core timerGreg Ungerer
Modify the m68knommu/ColdFire core timer code to use register offsets with raw_read/raw_write access, instead of a mapped struct. Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25Merge git://git.linux-nfs.org/pub/linux/nfs-2.6Linus Torvalds
* 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 ...
2006-06-25Merge master.kernel.org:/pub/scm/linux/kernel/git/mchehab/v4l-dvbLinus Torvalds
* master.kernel.org:/pub/scm/linux/kernel/git/mchehab/v4l-dvb: (244 commits) V4L/DVB (4210b): git-dvb: tea575x-tuner build fix V4L/DVB (4210a): git-dvb versus matroxfb V4L/DVB (4209): Added some BTTV PCI IDs for newer boards Fixes some sync issues between V4L/DVB development and GIT V4L/DVB (4206): Cx88-blackbird: always set encoder height based on tvnorm->id V4L/DVB (4205): Merge tda9887 module into tuner. V4L/DVB (4203): Explicitly set the enum values. V4L/DVB (4202): allow selecting CX2341x port mode V4L/DVB (4200): Disable bitrate_mode when encoding mpeg-1. V4L/DVB (4199): Add cx2341x-specific control array to cx2341x.c V4L/DVB (4198): Avoid newer usages of obsoleted experimental MPEGCOMP API V4L/DVB (4197): Port new MPEG API to saa7134-empress with saa6752hs V4L/DVB (4196): Port cx88-blackbird to the new MPEG API. V4L/DVB (4193): Update cx2341x fw encoding API doc. V4L/DVB (4192): Use control helpers for saa7115, cx25840, msp3400. V4L/DVB (4191): Add CX2341X MPEG encoder module. V4L/DVB (4190): Add helper functions for control processing to v4l2-common. V4L/DVB (4189): Add videodev support for VIDIOC_S/G/TRY_EXT_CTRLS. V4L/DVB (4188): Add new MPEG control/ioctl definitions to videodev2.h V4L/DVB (4186): Add support for the DNTV Live! mini DVB-T card. ...
2006-06-25[PATCH] Fix "biovec-(256)" in /proc/slabinfoAlexey Dobriyan
Stringify does what it was told to do. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] pacct: none-delayed process accounting accumulationKaiGai Kohei
In current 2.6.17 implementation, signal_struct refered from task_struct is used for per-process data structure. The pacct facility also uses it as a per-process data structure to store stime, utime, minflt, majflt. But those members are saved in __exit_signal(). It's too late. For example, if some threads exits at same time, pacct facility has a possibility to drop accountings for a part of those threads. (see, the following 'The results of original 2.6.17 kernel') I think accounting information should be completely collected into the per-process data structure before writing out an accounting record. This patch fixes this matter. Accumulation of stime, utime, minflt and majflt are done before generating accounting record. [mingo@elte.hu: fix acct_collect() siglock bug found by lockdep] Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] pacct: avoidance to refer the last thread as a representation of the ↵KaiGai Kohei
process When pacct facility generate an 'ac_flag' field in accounting record, it refers a task_struct of the thread which died last in the process. But any other task_structs are ignored. Therefore, pacct facility drops ASU flag even if root-privilege operations are used by any other threads except the last one. In addition, AFORK flag is always set when the thread of group-leader didn't die last, although this process has called execve() after fork(). We have a same matter in ac_exitcode. The recorded ac_exitcode is an exit code of the last thread in the process. There is a possibility this exitcode is not the group leader's one.
2006-06-25[PATCH] pacct: add pacct_struct to fix some pacct bugs.KaiGai Kohei
The pacct facility need an i/o operation when an accounting record is generated. There is a possibility to wake OOM killer up. If OOM killer is activated, it kills some processes to make them release process memory regions. But acct_process() is called in the killed processes context before calling exit_mm(), so those processes cannot release own memory. In the results, any processes stop in this point and it finally cause a system stall.