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* [PATCH] fix module sysfs files reference countingGreg Kroah-Hartman2006-03-202-56/+31
| | | | | | | | | | | | | The module files, refcnt, version, and srcversion did not properly increment the owner's module reference count, allowing the modules to be removed while the files were open, causing oopses. This patch fixes this, and also fixes the problem that the version and srcversion files were not showing up, unless CONFIG_MODULE_UNLOAD was enabled, which is not correct. Cc: Nathan Lynch <ntl@pobox.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] add EXPORT_SYMBOL_GPL_FUTURE() to RCU subsystemGreg Kroah-Hartman2006-03-201-3/+3
| | | | | | | | | As the RCU symbols are going to be changed to GPL in the near future, lets warn users that this is going to happen. Cc: Paul McKenney <paulmck@us.ibm.com> Acked-by: Dipankar Sarma <dipankar@in.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] add EXPORT_SYMBOL_GPL_FUTURE()Greg Kroah-Hartman2006-03-201-2/+47
| | | | | | | | This patch adds the ability to mark symbols that will be changed in the future, so that kernel modules that don't include MODULE_LICENSE("GPL") and use the symbols, will be flagged and printed out to the system log. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] Clean up module.c symbol searching logicSam Ravnborg2006-03-201-32/+41
| | | | | Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] kobject: fix build error if CONFIG_SYSFS=nJun'ichi Nomura2006-03-201-3/+0
| | | | | | | | | Moving uevent_seqnum and uevent_helper to kobject_uevent.c because they are used even if CONFIG_SYSFS=n while kernel/ksysfs.c is built only if CONFIG_SYSFS=y, Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] don't do exit_io_context() until we know we won't be doing any IOAl Viro2006-03-181-2/+5
| | | | | | | | | | | | | | | testcase: mount /dev/sdb10 /mnt touch /mnt/tmp/b umount /mnt mount /dev/sdb10 /mnt rm /mnt/tmp/b </mnt/tmp/b umount /mnt and watch blkdev_ioc line in /proc/slabinfo. Vanilla kernel leaks. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [PATCH] disable unshare(CLONE_VM) for nowOleg Nesterov2006-03-181-3/+1
| | | | | | | | | | | | | sys_unshare() does mmput(new_mm). This is not enough if we have mm->core_waiters. This patch is a temporary fix for soon to be released 2.6.16. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> [ Checked with Uli: "I'm not planning to use unshare(CLONE_VM). It's not needed for any functionality planned so far. What we (as in Red Hat) need unshare() for now is the filesystem side." ] Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] posix-timers: fix requeue accounting when signal is ignoredRoman Zippel2006-03-171-0/+1
| | | | | | | | | | | When the posix-timer signal is ignored then the timer is rearmed by the callback function. The requeue pending accounting has to be fixed up else the state might be wrong. Signed-off-by: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] time_interpolator: add __read_mostlyChristoph Lameter2006-03-171-2/+2
| | | | | | | | | | The pointer to the current time interpolator and the current list of time interpolators are typically only changed during bootup. Adding __read_mostly takes them away from possibly hot cachelines. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] unshare: Use rcu_assign_pointer when setting sighandEric W. Biederman2006-03-171-1/+1
| | | | | | | | | | | | | | The sighand pointer only needs the rcu_read_lock on the read side. So only depending on task_lock protection when setting this pointer is not enough. We also need a memory barrier to ensure the initialization is seen first. Use rcu_assign_pointer as it does this for us, and clearly documents that we are setting an rcu readable pointer. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Fix sigaltstack corruption among cloned threadsGOTO Masanori2006-03-141-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes alternate signal stack corruption among cloned threads with CLONE_SIGHAND (and CLONE_VM) for linux-2.6.16-rc6. The value of alternate signal stack is currently inherited after a call of clone(... CLONE_SIGHAND | CLONE_VM). But if sigaltstack is set by a parent thread, and then if multiple cloned child threads (+ parent threads) call signal handler at the same time, some threads may be conflicted - because they share to use the same alternative signal stack region. Finally they get sigsegv. It's an undesirable race condition. Note that child threads created from NPTL pthread_create() also hit this conflict when the parent thread uses sigaltstack, without my patch. To fix this problem, this patch clears the child threads' sigaltstack information like exec(). This behavior follows the SUSv3 specification. In SUSv3, pthread_create() says "The alternate stack shall not be inherited (when new threads are initialized)". It means that sigaltstack should be cleared when sigaltstack memory space is shared by cloned threads with CLONE_SIGHAND. Note that I chose "if (clone_flags & CLONE_SIGHAND)" line because: - If clone_flags line is not existed, fork() does not inherit sigaltstack. - CLONE_VM is another choice, but vfork() does not inherit sigaltstack. - CLONE_SIGHAND implies CLONE_VM, and it looks suitable. - CLONE_THREAD is another candidate, and includes CLONE_SIGHAND + CLONE_VM, but this flag has a bit different semantics. I decided to use CLONE_SIGHAND. [ Changed to test for CLONE_VM && !CLONE_VFORK after discussion --Linus ] Signed-off-by: GOTO Masanori <gotom@sanori.org> Cc: Roland McGrath <roland@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Acked-by: Linus Torvalds <torvalds@osdl.org> Cc: Ulrich Drepper <drepper@redhat.com> Cc: Jakub Jelinek <jakub@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] remove __put_task_struct_cb export againChristoph Hellwig2006-03-112-8/+3
| | | | | | | | | | | | | | | | | | | The patch '[PATCH] RCU signal handling' [1] added an export for __put_task_struct_cb, a put_task_struct helper newly introduced in that patch. But the put_task_struct couldn't be used modular previously as __put_task_struct wasn't exported. There are not callers of it in modular code, and it shouldn't be exported because we don't want drivers to hold references to task_structs. This patch removes the export and folds __put_task_struct into __put_task_struct_cb as there's no other caller. [1] http://www2.kernel.org/git/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=e56d090310d7625ecb43a1eeebd479f04affb48b Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix file countingDipankar Sarma2006-03-081-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I have benchmarked this on an x86_64 NUMA system and see no significant performance difference on kernbench. Tested on both x86_64 and powerpc. The way we do file struct accounting is not very suitable for batched freeing. For scalability reasons, file accounting was constructor/destructor based. This meant that nr_files was decremented only when the object was removed from the slab cache. This is susceptible to slab fragmentation. With RCU based file structure, consequent batched freeing and a test program like Serge's, we just speed this up and end up with a very fragmented slab - llm22:~ # cat /proc/sys/fs/file-nr 587730 0 758844 At the same time, I see only a 2000+ objects in filp cache. The following patch I fixes this problem. This patch changes the file counting by removing the filp_count_lock. Instead we use a separate percpu counter, nr_files, for now and all accesses to it are through get_nr_files() api. In the sysctl handler for nr_files, we populate files_stat.nr_files before returning to user. Counting files as an when they are created and destroyed (as opposed to inside slab) allows us to correctly count open files with RCU. Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] rcu batch tuningDipankar Sarma2006-03-081-18/+58
| | | | | | | | | | | | | | | | | | | | | This patch adds new tunables for RCU queue and finished batches. There are two types of controls - number of completed RCU updates invoked in a batch (blimit) and monitoring for high rate of incoming RCUs on a cpu (qhimark, qlowmark). By default, the per-cpu batch limit is set to a small value. If the input RCU rate exceeds the high watermark, we do two things - force quiescent state on all cpus and set the batch limit of the CPU to INTMAX. Setting batch limit to INTMAX forces all finished RCUs to be processed in one shot. If we have more than INTMAX RCUs queued up, then we have bigger problems anyway. Once the incoming queued RCUs fall below the low watermark, the batch limit is set to the default. Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] idle threads should have a sane ->timestamp valueIngo Molnar2006-03-081-0/+1
| | | | | | | | | | | | Idle threads should have a sane ->timestamp value, to avoid init kernel thread(s) from inheriting it and causing miscalculations in try_to_wake_up(). Reported-by: Mike Galbraith <efault@gmx.de>. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] time: add barrier after updating jiffies_64Atsushi Nemoto2006-03-061-0/+2
| | | | | | | | | | | Add a compiler barrier so that we don't read jiffies before updating jiffies_64. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix next_timer_interrupt() for hrtimerTony Lindgren2006-03-062-0/+51
| | | | | | | | | | | | | | | | | | | | | Also from Thomas Gleixner <tglx@linutronix.de> Function next_timer_interrupt() got broken with a recent patch 6ba1b91213e81aa92b5cf7539f7d2a94ff54947c as sys_nanosleep() was moved to hrtimer. This broke things as next_timer_interrupt() did not check hrtimer tree for next event. Function next_timer_interrupt() is needed with dyntick (CONFIG_NO_IDLE_HZ, VST) implementations, as the system can be in idle when next hrtimer event was supposed to happen. At least ARM and S390 currently use next_timer_interrupt(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Add early-boot-safety check to cond_resched()Linus Torvalds2006-03-061-0/+2
| | | | | | | | | | | | | Just to be safe, we should not trigger a conditional reschedule during the early boot sequence. We've historically done some questionable early on, and the safety warnings in __might_sleep() are generally turned off during that period, so there might be problems lurking. This affects CONFIG_PREEMPT_VOLUNTARY, which takes over might_sleep() to cause a voluntary conditional reschedule. Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] time_interpolator: Use readq_relaxed() instead of readq().Christoph Lameter2006-03-021-2/+2
| | | | | | | | | | | | | | | | On some platforms readq performs additional work to make sure I/O is done in a coherent way. This is not needed for time retrieval as done by the time interpolator. So we can use readq_relaxed instead which will improve performance. It affects sparc64 and ia64 only. Apparently it makes a significant difference on ia64. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: john stultz <johnstul@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix acpi_video_flags on x86-64Stefan Seyfried2006-03-021-1/+1
| | | | | | | | | | | | acpi_video_flags variable is unsigned long, so it should be set as such. This actually matters on x86-64. Signed-off-by: Stefan Seyfried <seife@suse.de> Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: "Brown, Len" <len.brown@intel.com> Cc: Andi Kleen <ak@muc.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [IA64] sysctl option to silence unaligned trap warningsJes Sorensen2006-02-281-0/+14
| | | | | | | | | | | | Allow sysadmin to disable all warnings about userland apps making unaligned accesses by using: # echo 1 > /proc/sys/kernel/ignore-unaligned-usertrap Rather than having to use prctl on a process by process basis. Default behaivour leaves the warnings enabled. Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
* [PATCH] kjournald keeps reference to namespaceBjörn Steinbrink2006-02-201-0/+3
| | | | | | | | | | | | | | | | In daemonize() a new thread gets cleaned up and 'merged' with init_task. The current fs_struct is handled there, but not the current namespace. This adds the namespace part. [ Eric Biederman pointed out the namespace wrappers, and also notes that we can't ever count on using our parents namespace because we already have called exit_fs(), which is the only way to the namespace from a process. ] Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de> Acked-by: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Merge branch 'fixes.b8' of ↵Linus Torvalds2006-02-201-3/+3
|\ | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/bird
| * [PATCH] GFP_KERNEL allocations in atomic (auditsc)Al Viro2006-02-181-3/+3
| | | | | | | | | | | | | | | | audit_log_exit() is called from atomic contexts and gets explicit gfp_mask argument; it should use it for all allocations rather than doing some with gfp_mask and some with GFP_KERNEL. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | [PATCH] Fix compile for CONFIG_SYSVIPC=n or CONFIG_SYSCTL=nStephen Rothwell2006-02-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The compat syscalls are added to sys_ni.c since they are not defined if the above CONFIG options are off. Also, nfs would not build with CONFIG_SYSCTL off. Noticed by Arthur Othieno. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] Fix undefined symbols for nommu architectureLuke Yang2006-02-201-0/+2
| | | | | | | | | | | | | | Signed-off-by: Luke Yang <luke.adi@gmail.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* | [PATCH] suspend-to-ram: allow video options to be set at runtimePavel Machek2006-02-201-4/+12
|/ | | | | | | | | | | | | | | | | | Currently, acpi video options can only be set on kernel command line. That's little inflexible; I'd like userland s2ram application that just works, and modifying kernel command line according to whitelist is not fun. It is better to just allow s2ram application to set video options just before suspend (according to the whitelist). This implements sysctl to allow setting suspend video options without reboot. (akpm: Documentation updates for this new sysctl are pending..) Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: "Brown, Len" <len.brown@intel.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] swsusp: fix breakage with swap on LVMRafael J. Wysocki2006-02-171-3/+1
| | | | | | | | | | Restore the compatibility with the older code and make it possible to suspend if the kernel command line doesn't contain the "resume=" argument Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Introduce CONFIG_DEFAULT_MIGRATION_COSTIngo Molnar2006-02-171-1/+12
| | | | | | | | | | | | | | | | | | | | | Heiko Carstens <heiko.carstens@de.ibm.com> wrote: The boot sequence on s390 sometimes takes ages and we spend a very long time (up to one or two minutes) in calibrate_migration_costs. The time spent there differs from boot to boot. Also the calculated costs differ a lot. I've seen differences by up to a factor of 15 (yes, factor not percent). Also I doubt that making these measurements make much sense on a completely virtualized architecture where you cannot tell how much cpu time you will get anyway. So introduce the CONFIG_DEFAULT_MIGRATION_COST method for an architecture to set the scheduler migration costs. This turns off automatic detection of migration costs. Makes sense on virtual platforms, where migration costs are hard to measure accurately. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Provide an interface for getting the current tick lengthPaul Mackerras2006-02-171-5/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This provides an interface for arch code to find out how many nanoseconds are going to be added on to xtime by the next call to do_timer. The value returned is a fixed-point number in 52.12 format in nanoseconds. The reason for this format is that it gives the full precision that the timekeeping code is using internally. The motivation for this is to fix a problem that has arisen on 32-bit powerpc in that the value returned by do_gettimeofday drifts apart from xtime if NTP is being used. PowerPC is now using a lockless do_gettimeofday based on reading the timebase register and performing some simple arithmetic. (This method of getting the time is also exported to userspace via the VDSO.) However, the factor and offset it uses were calculated based on the nominal tick length and weren't being adjusted when NTP varied the tick length. Note that 64-bit powerpc has had the lockless do_gettimeofday for a long time now. It also had an extremely hairy routine that got called from the 32-bit compat routine for adjtimex, which adjusted the factor and offset according to what it thought the timekeeping code was going to do. Not only was this only called if a 32-bit task did adjtimex (i.e. not if a 64-bit task did adjtimex), it was also duplicating computations from kernel/timer.c and it wasn't clear that it was (still) correct. The simple solution is to ask the timekeeping code how long the current jiffy will be on each timer interrupt, after calling do_timer. If this jiffy will be a different length from the last one, we then need to compute new values for the factor and offset used in the lockless do_gettimeofday. In this way we can keep xtime and do_gettimeofday in sync, even when NTP is varying the tick length. Note that when adjtimex varies the tick length, it almost always introduces the variation from the next tick on. The only case I could see where adjtimex would vary the length of the current tick is when an old-style adjtime adjustment is being cancelled. (It's not clear to me why the adjustment has to be cancelled immediately rather than from the next tick on.) Thus I don't see any real need for a hook in adjtimex; the rare case of an old-style adjustment being cancelled can be fixed up at the next tick. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: john stultz <johnstul@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] x86_64: Add boot option to disable randomized mappings and cleanupAndi Kleen2006-02-171-2/+0
| | | | | | | | | | | | | AMD SimNow!'s JIT doesn't like them at all in the guest. For distribution installation it's easiest if it's a boot time option. Also I moved the variable to a more appropiate place and make it independent from sysctl And marked __read_mostly which it is. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] swsusp: nuke noisy messageAndrew Morton2006-02-151-3/+1
| | | | | | | | | I get about 88 squillion of these when suspending an old ad450nx server. Cc: Pavel Roskin <proski@gnu.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpuset: oops in exit on null cpuset fixPaul Jackson2006-02-151-1/+34
| | | | | | | | | | | | | | | Fix a latent bug in cpuset_exit() handling. If a task tried to allocate memory after calling cpuset_exit(), it oops'd in cpuset_update_task_memory_state() on a NULL cpuset pointer. So set the exiting tasks cpuset to the root cpuset instead of to NULL. A distro kernel hit this with an added kernel package that had just such a hook (allocating memory) in the exit code path. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix zap_thread's ptrace related problemsOleg Nesterov2006-02-151-10/+15
| | | | | | | | | | | | | | | 1. The tracee can go from ptrace_stop() to do_signal_stop() after __ptrace_unlink(p). 2. It is unsafe to __ptrace_unlink(p) while p->parent may wait for tasklist_lock in ptrace_detach(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Roland McGrath <roland@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Christoph Hellwig <hch@lst.de> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix kill_proc_info() vs fork() theoretical raceOleg Nesterov2006-02-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | copy_process: attach_pid(p, PIDTYPE_PID, p->pid); attach_pid(p, PIDTYPE_TGID, p->tgid); What if kill_proc_info(p->pid) happens in between? copy_process() holds current->sighand.siglock, so we are safe in CLONE_THREAD case, because current->sighand == p->sighand. Otherwise, p->sighand is unlocked, the new process is already visible to the find_task_by_pid(), but have a copy of parent's 'struct pid' in ->pids[PIDTYPE_TGID]. This means that __group_complete_signal() may hang while doing do ... while (next_thread() != p) We can solve this problem if we reverse these 2 attach_pid()s: attach_pid() does wmb() group_send_sig_info() calls spin_lock(), which provides a read barrier. // Yes ? I don't think we can hit this race in practice, but still. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Roland McGrath <roland@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix kill_proc_info() vs CLONE_THREAD raceOleg Nesterov2006-02-151-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | There is a window after copy_process() unlocks ->sighand.siglock and before it adds the new thread to the thread list. In that window __group_complete_signal(SIGKILL) will not see the new thread yet, so this thread will start running while the whole thread group was supposed to exit. I beleive we have another good reason to place attach_pid(PID/TGID) under ->sighand.siglock. We can do the same for release_task()->__unhash_process() de_thread()->switch_exec_pids() After that we don't need tasklist_lock to iterate over the thread list, and we can simplify things, see for example do_sigaction() or sys_times(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Roland McGrath <roland@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] hrtimer: round up relative start time on low-res archesIngo Molnar2006-02-141-1/+12
| | | | | | | | | | | | | CONFIG_TIME_LOW_RES is a temporary way for architectures to signal that they simply return xtime in do_gettimeoffset(). In this corner-case we want to round up by resolution when starting a relative timer, to avoid short timeouts. This will go away with the GTOD framework. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: revert "filter affine wakeups"Chen, Kenneth W2006-02-141-9/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert commit d7102e95b7b9c00277562c29aad421d2d521c5f6: [PATCH] sched: filter affine wakeups Apparently caused more than 10% performance regression for aim7 benchmark. The setup in use is 16-cpu HP rx8620, 64Gb of memory and 12 MSA1000s with 144 disks. Each disk is 72Gb with a single ext3 filesystem (courtesy of HP, who supplied benchmark results). The problem is, for aim7, the wake-up pattern is random, but it still needs load balancing action in the wake-up path to achieve best performance. With the above commit, lack of load balancing hurts that workload. However, for workloads like database transaction processing, the requirement is exactly opposite. In the wake up path, best performance is achieved with absolutely zero load balancing. We simply wake up the process on the CPU that it was previously run. Worst performance is obtained when we do load balancing at wake up. There isn't an easy way to auto detect the workload characteristics. Ingo's earlier patch that detects idle CPU and decide whether to load balance or not doesn't perform with aim7 either since all CPUs are busy (it causes even bigger perf. regression). Revert commit d7102e95b7b9c00277562c29aad421d2d521c5f6, which causes more than 10% performance regression with aim7. Signed-off-by: Ken Chen <kenneth.w.chen@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] compound page: no access_process_vm checkHugh Dickins2006-02-141-2/+1
| | | | | | | | | | | The PageCompound check before access_process_vm's set_page_dirty_lock is no longer necessary, so remove it. But leave the PageCompound checks in bio_set_pages_dirty, dio_bio_complete and nfs_free_user_pages: at least some of those were introduced as a little optimization on hugetlb pages. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] prevent recursive panic from softlockup watchdogJan Beulich2006-02-101-0/+1
| | | | | | | | | When panic_timeout is zero, suppress triggering a nested panic due to soft lockup detection. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sched: remove smpniceNick Piggin2006-02-101-111/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I don't think the code is quite ready, which is why I asked for Peter's additions to also be merged before I acked it (although it turned out that it still isn't quite ready with his additions either). Basically I have had similar observations to Suresh in that it does not play nicely with the rest of the balancing infrastructure (and raised similar concerns in my review). The samples (group of 4) I got for "maximum recorded imbalance" on a 2x2 SMP+HT Xeon are as follows: | Following boot | hackbench 20 | hackbench 40 -----------+----------------+---------------------+--------------------- 2.6.16-rc2 | 30,37,100,112 | 5600,5530,6020,6090 | 6390,7090,8760,8470 +nosmpnice | 3, 2, 4, 2 | 28, 150, 294, 132 | 348, 348, 294, 347 Hackbench raw performance is down around 15% with smpnice (but that in itself isn't a huge deal because it is just a benchmark). However, the samples show that the imbalance passed into move_tasks is increased by about a factor of 10-30. I think this would also go some way to explaining latency blips turning up in the balancing code (though I haven't actually measured that). We'll probably have to revert this in the SUSE kernel. Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Peter Williams <pwil3058@bigpond.net.au> Cc: "Martin J. Bligh" <mbligh@aracnet.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] do_sigaction: cleanup ->sa_mask manipulationOleg Nesterov2006-02-091-5/+3
| | | | | | | Clear unblockable signals beforehand. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] sys_signal: initialize ->sa_maskOleg Nesterov2006-02-091-0/+1
| | | | | | | | | | | | Pointed out by Linus Torvalds. sys_signal() forgets to initialize ->sa_mask. ( I suspect arch/ia64/ia32/ia32_signal.c:sys32_signal() also needs this fix ) Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] kernel/sys.c NULL noise removalAl Viro2006-02-071-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [PATCH] timer.c NULL noise removalAl Viro2006-02-071-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [PATCH] remove bogus asm/bug.h includes.Al Viro2006-02-071-1/+0
| | | | | | | A bunch of asm/bug.h includes are both not needed (since it will get pulled anyway) and bogus (since they are done too early). Removed. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [PATCH] unshare system call -v5: unshare filesJANAK DESAI2006-02-071-30/+51
| | | | | | | | | | | | | | If the file descriptor structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai <janak@us.ibm.com> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Michael Kerrisk <mtk-manpages@gmx.net> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] unshare system call -v5: unshare vmJANAK DESAI2006-02-071-31/+56
| | | | | | | | | | | | | | If vm structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai <janak@us.ibm.com> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Michael Kerrisk <mtk-manpages@gmx.net> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] unshare system call -v5: unshare namespaceJANAK DESAI2006-02-071-6/+11
| | | | | | | | | | | | | | If the namespace structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai <janak@us.ibm.com> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Michael Kerrisk <mtk-manpages@gmx.net> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] unshare system call -v5: unshare filesystem infoJANAK DESAI2006-02-071-3/+6
| | | | | | | | | | | | | | If filesystem structure is being shared, allocate a new one and copy information from the current, shared, structure. Signed-off-by: Janak Desai <janak@us.ibm.com> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Cc: Michael Kerrisk <mtk-manpages@gmx.net> Cc: Andi Kleen <ak@muc.de> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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