summaryrefslogtreecommitdiffstats
path: root/kernel/posix-timers.c
Commit message (Collapse)AuthorAgeFilesLines
* posix-timers: Prevent softirq starvation by small intervals and SIG_IGNThomas Gleixner2007-06-211-2/+33
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | posix-timers which deliver an ignored signal are currently rearmed in the timer softirq: This is necessary because the timer needs to be delivered again when SIG_IGN is removed. This is not a problem, when the interval is reasonable. With high resolution timers enabled one might arm a posix timer with a very small interval and ignore the signal. This might lead to a softirq starvation when the interval is so small that the timer is requeued onto the softirq pending list right away. This problem was pointed out by Jan Kiszka. Thanks Jan ! The correct solution would be to stop the timer, when the signal is ignored and rearm it when SIG_IGN is removed. Unfortunately this requires modification in sigaction and involves non trivial sighand locking. It's too late in the release cycle for such a change. For now we just keep the timer running and enforce that the timer only fires every jiffie. This does not break anything as we keep the overrun counter correct. It adds a little inaccuracy to the timer_gettime() interface, but... The more complex change is necessary anyway to fix another short coming of the current implementation, which I discovered while looking at this problem: A pending signal is discarded when SIG_IGN is set. In case that a posixtimer signal is pending then it is discarded as well, but when SIG_IGN is removed later nothing rearms the timer. This is not new, it's that way since posix timers have been merged. So nothing to worry about right now. I have a working solution to fix all of this, but the impact is too large for both stable and 2.6.22. I'm going to send it out for review in the next days. This should go into 2.6.21.stable as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Jan Kiszka <jan.kiszka@web.de> Cc: Ulrich Drepper <drepper@redhat.com> Cc: Stable Team <stable@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* header cleaning: don't include smp_lock.h when not usedRandy Dunlap2007-05-081-1/+0
| | | | | | | | | | | | Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] hrtimers: add high resolution timer supportThomas Gleixner2007-02-161-1/+1
| | | | | | | | | | | | | Implement high resolution timers on top of the hrtimers infrastructure and the clockevents / tick-management framework. This provides accurate timers for all hrtimer subsystem users. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] hrtimers: namespace and enum cleanupThomas Gleixner2007-02-161-6/+7
| | | | | | | | | | | | | | | | | | | - hrtimers did not use the hrtimer_restart enum and relied on the implict int representation. Fix the prototypes and the functions using the enums. - Use seperate name spaces for the enumerations - Convert hrtimer_restart macro to inline function - Add comments No functional changes. [akpm@osdl.org: fix input driver] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc().Robert P. J. Day2007-02-111-2/+1
| | | | | | | | | | | | | | | | | | | | | | Replace appropriate pairs of "kmem_cache_alloc()" + "memset(0)" with the corresponding "kmem_cache_zalloc()" call. Signed-off-by: Robert P. J. Day <rpjday@mindspring.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: Roland McGrath <roland@redhat.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Greg KH <greg@kroah.com> Acked-by: Joel Becker <Joel.Becker@oracle.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Jan Kara <jack@ucw.cz> Cc: Michael Halcrow <mhalcrow@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] slab: remove kmem_cache_tChristoph Lameter2006-12-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* fix file specification in commentsUwe Zeisberger2006-10-031-1/+1
| | | | | | | Many files include the filename at the beginning, serveral used a wrong one. Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] posix-timers: Fix clock_nanosleep() doesn't return the remaining ↵Toyo Abe2006-09-291-0/+21
| | | | | | | | | | | | | | | | | | | | | | | time in compatibility mode The clock_nanosleep() function does not return the time remaining when the sleep is interrupted by a signal. This patch creates a new call out, compat_clock_nanosleep_restart(), which handles returning the remaining time after a sleep is interrupted. This patch revives clock_nanosleep_restart(). It is now accessed via the new call out. The compat_clock_nanosleep_restart() is used for compatibility access. Since this is implemented in compatibility mode the normal path is virtually unaffected - no real performance impact. Signed-off-by: Toyo Abe <toyoa@mvista.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] hrtimers: remove data fieldRoman Zippel2006-03-261-5/+4
| | | | | | | | | | | | The nanosleep cleanup allows to remove the data field of hrtimer. The callback function can use container_of() to get it's own data. Since the hrtimer structure is anyway embedded in other structures, this adds no overhead. 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] hrtimers: posix-timer: cleanup common_timer_get()Roman Zippel2006-03-261-24/+26
| | | | | | | | | Cleanup common_timer_get() a little. 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] hrtimers: pass current time to hrtimer_forward()Roman Zippel2006-03-261-4/+10
| | | | | | | | | | | Pass current time to hrtimer_forward(). This allows to use the softirq time in the timer base when the forward function is called from the timer callback. Other places pass current time with a call to timer->base->get_time(). 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] sem2mutex: kernel/Arjan van de Ven2006-03-231-0/+1
| | | | | | | | | | | | Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Arjan van de Ven <arjan@infradead.org> 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] 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] kernel/posix-timers.c: remove do_posix_clock_notimer_create()Adrian Bunk2006-02-011-6/+0
| | | | | | | | | This function is neither used nor has any real contents. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] hrtimers: set correct initial expiry time for relative SIGEV_NONE timersThomas Gleixner2006-02-011-1/+6
| | | | | | | | | | | The expiry time for relative timers with SIGEV_NONE set was never updated to the correct value. Pointed out by George Anzinger. 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] hrtimers: cleanups and simplificationsGeorge Anzinger2006-02-011-28/+9
| | | | | | | | | | | | Clean up the interface to hrtimers by changing the init code to pass the mode as well as the clock. This allow the init code to select the correct base and eliminates extra timer re-init code in posix-timers. We also simplify the restart interface nanosleep use. Signed-off-by: George Anzinger <george@mvista.com> 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] hrtimers: fix possible use of NULL pointer in posix-timersThomas Gleixner2006-02-011-1/+2
| | | | | | | | Fixup the conversion of posix-timers to hrtimers. 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] Unlinline a bunch of other functionsArjan van de Ven2006-01-141-4/+4
| | | | | | | | | | | Remove the "inline" keyword from a bunch of big functions in the kernel with the goal of shrinking it by 30kb to 40kb Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jeff Garzik <jgarzik@pobox.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] hrtimer: convert posix timers completelyThomas Gleixner2006-01-101-582/+135
| | | | | | | | | | | | - convert posix-timers.c to use hrtimers - remove the now obsolete abslist code Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] hrtimer: switch clock_nanosleep to hrtimer nanosleep APIThomas Gleixner2006-01-101-124/+27
| | | | | | | | | Switch clock_nanosleep to use the new nanosleep functions in hrtimer.c Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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] hrtimer: create and use timespec_valid macroThomas Gleixner2006-01-101-3/+2
| | | | | | | | | add timespec_valid(ts) [returns false if the timespec is denorm] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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] hrtimer: make clockid_t arguments constThomas Gleixner2006-01-101-17/+21
| | | | | | | | | add const arguments to the posix-timers.h API functions Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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] hrtimer: remove duplicate div_long_long_rem implementationThomas Gleixner2006-01-101-9/+1
| | | | | | | | | make posix-timers.c use the generic calc64.h facility Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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] timespec: normalize off by one errorsGeorge Anzinger2005-11-131-7/+3
| | | | | | | | | | It would appear that the timespec normalize code has an off by one error. Found in three places. Thanks to Ben for spotting. Signed-off-by: George Anzinger<george@mvista.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] posix-timers: use schedule_timeout() in common_nsleep()Oleg Nesterov2005-10-301-18/+1
| | | | | | | | | common_nsleep() reimplements schedule_timeout_interruptible() for unknown reason. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Call exit_itimers from do_exit, not __exit_signalRoland McGrath2005-10-211-1/+1
| | | | | | | | | | | | | | | | | When I originally moved exit_itimers into __exit_signal, that was the only place where we could reliably know it was the last thread in the group dying, without races. Since then we've gotten the signal_struct.live counter, and do_exit can reliably do group-wide cleanup work. This patch moves the call to do_exit, where it's made without locks. This avoids the deadlock issues that the old __exit_signal code's comment talks about, and the one that Oleg found recently with process CPU timers. [ This replaces e03d13e985d48ac4885382c9e3b1510c78bd047f, which is why it was just reverted. ] Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] fix send_sigqueue() vs thread exit raceOleg Nesterov2005-09-071-13/+15
| | | | | | | | | | | | | | | | | | | posix_timer_event() first checks that the thread (SIGEV_THREAD_ID case) does not have PF_EXITING flag, then it calls send_sigqueue() which locks task list. But if the thread exits in between the kernel will oops (->sighand == NULL after __exit_sighand). This patch moves the PF_EXITING check into the send_sigqueue(), it must be done atomically under tasklist_lock. When send_sigqueue() detects exiting thread it returns -1. In that case posix_timer_event will send the signal to thread group. Also, this patch fixes task_struct use-after-free in posix_timer_event. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] revert "timer exit cleanup"Andrew Morton2005-08-041-1/+0
| | | | | | | | | | Revert this June 17 patch: it broke persistence of timers across execve(). Cc: Roland McGrath <roland@redhat.com> Cc: george anzinger <george@mvista.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] posix timers: fix normalization problemGeorge Anzinger2005-07-281-14/+3
| | | | | | | | | | | | | | | | | | | | | | | (We found this (after a customer complained) and it is in the kernel.org kernel. Seems that for CLOCK_MONOTONIC absolute timers and clock_nanosleep calls both the request time and wall_to_monotonic are subtracted prior to the normalize resulting in an overflow in the existing normalize test. This causes the result to be shifted ~4 seconds ahead instead of ~2 seconds back in time.) The normalize code in posix-timers.c fails when the tv_nsec member is ~1.2 seconds negative. This can happen on absolute timers (and clock_nanosleeps) requested on CLOCK_MONOTONIC (both the request time and wall_to_monotonic are subtracted resulting in the possibility of a number close to -2 seconds.) This fix uses the set_normalized_timespec() (which does not have an overflow problem) to fix the problem and as a side effect makes the code cleaner. Signed-off-by: George Anzinger <george@mvista.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] posix-timers: use try_to_del_timer_sync()Oleg Nesterov2005-06-231-27/+7
| | | | | | | | | | | | | | sys_timer_settime/sys_timer_delete needs to delete k_itimer->real.timer synchronously while holding ->it_lock, which is also locked in posix_timer_fn. This patch removes timer_active/set_timer_inactive which plays with timer_list's internals in favour of using try_to_del_timer_sync(), which was introduced in the previous patch. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] timer exit cleanupIngo Molnar2005-06-171-0/+1
| | | | | | | Do all timer zapping in exit_itimers. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+1584
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!