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2008-11-19tracking-2.6.28-timer-blowup.patchAndy Green
Signed-off-by: Andy Green <andy@openmoko.com>
2008-11-06Add round_jiffies_up and related routinesAlan Stern
This patch (as1158b) adds round_jiffies_up() and friends. These routines work like the analogous round_jiffies() functions, except that they will never round down. The new routines will be useful for timeouts where we don't care exactly when the timer expires, provided it doesn't expire too soon. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-20Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', ↵Thomas Gleixner
'timers/ntp', 'timers/posixtimers' and 'timers/debug' into v28-timers-for-linus
2008-08-21migrate_timers: add comment, use spinlock_irq()Oleg Nesterov
Add the comment to explain why the double lock in migrate_timers() can't deadlock. Change the code to use spinlock_irq() instead of local_irq_disable() + spin_lock(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-11printk: robustify printkPeter Zijlstra
Avoid deadlocks against rq->lock and xtime_lock by deferring the klogd wakeup by polling from the timer tick. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (241 commits) [ARM] 5171/1: ep93xx: fix compilation of modules using clocks [ARM] 5133/2: at91sam9g20 defconfig file [ARM] 5130/4: Support for the at91sam9g20 [ARM] 5160/1: IOP3XX: gpio/gpiolib support [ARM] at91: Fix NAND FLASH timings for at91sam9x evaluation kits. [ARM] 5084/1: zylonite: Register AC97 device [ARM] 5085/2: PXA: Move AC97 over to the new central device declaration model [ARM] 5120/1: pxa: correct platform driver names for PXA25x and PXA27x UDC drivers [ARM] 5147/1: pxaficp_ir: drop pxa_gpio_mode calls, as pin setting [ARM] 5145/1: PXA2xx: provide api to control IrDA pins state [ARM] 5144/1: pxaficp_ir: cleanup includes [ARM] pxa: remove pxa_set_cken() [ARM] pxa: allow clk aliases [ARM] Feroceon: don't disable BPU on boot [ARM] Orion: LED support for HP mv2120 [ARM] Orion: add RD88F5181L-FXO support [ARM] Orion: add RD88F5181L-GE support [ARM] Orion: add Netgear WNR854T support [ARM] s3c2410_defconfig: update for current build [ARM] Acer n30: Minor style and indentation fixes. ...
2008-05-25Remove argument from open_softirq which is always NULLCarlos R. Mafra
As git-grep shows, open_softirq() is always called with the last argument being NULL block/blk-core.c: open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL); kernel/hrtimer.c: open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq, NULL); kernel/rcuclassic.c: open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL); kernel/rcupreempt.c: open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL); kernel/sched.c: open_softirq(SCHED_SOFTIRQ, run_rebalance_domains, NULL); kernel/softirq.c: open_softirq(TASKLET_SOFTIRQ, tasklet_action, NULL); kernel/softirq.c: open_softirq(HI_SOFTIRQ, tasklet_hi_action, NULL); kernel/timer.c: open_softirq(TIMER_SOFTIRQ, run_timer_softirq, NULL); net/core/dev.c: open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL); net/core/dev.c: open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL); This observation has already been made by Matthew Wilcox in June 2002 (http://www.cs.helsinki.fi/linux/linux-kernel/2002-25/0687.html) "I notice that none of the current softirq routines use the data element passed to them." and the situation hasn't changed since them. So it appears we can safely remove that extra argument to save 128 (54) bytes of kernel data (text). Signed-off-by: Carlos R. Mafra <crmafra@ift.unesp.br> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-12dyntick: Remove last reminants of dyntick supportRussell King
Remove the last reminants of dyntick support from the generic kernel. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-04-30debugobjects: add timer specific object debugging codeThomas Gleixner
Add calls to the generic object debugging infrastructure and provide fixup functions which allow to keep the system alive when recoverable problems have been detected by the object debugging core code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-17timers: simplify lockdep handlingOleg Nesterov
In order to avoid the false positive from lockdep, each per-cpu base->lock has the separate lock class and migrate_timers() uses double_spin_lock(). This all is overcomplicated: except for migrate_timers() we never take 2 locks at once, and migrate_timers() can use spin_lock_nested(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-03-26NOHZ: reevaluate idle sleep length after add_timer_on()Thomas Gleixner
add_timer_on() can add a timer on a CPU which is currently in a long idle sleep, but the timer wheel is not reevaluated by the nohz code on that CPU. So a timer can be delayed for quite a long time. This triggered a false positive in the clocksource watchdog code. To avoid this we need to wake up the idle CPU and enforce the reevaluation of the timer wheel for the next timer event. Add a function, which checks a given CPU for idle state, marks the idle task with NEED_RESCHED and sends a reschedule IPI to notify the other CPU of the change in the timer wheel. Call this function from add_timer_on(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: stable@kernel.org -- include/linux/sched.h | 6 ++++++ kernel/sched.c | 43 +++++++++++++++++++++++++++++++++++++++++++ kernel/timer.c | 10 +++++++++- 3 files changed, 58 insertions(+), 1 deletion(-)
2008-02-08kernel: remove fastcall in kernel/*Harvey Harrison
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08Pidns: make full use of xxx_vnr() callsPavel Emelyanov
Some time ago the xxx_vnr() calls (e.g. pid_vnr or find_task_by_vpid) were _all_ converted to operate on the current pid namespace. After this each call like xxx_nr_ns(foo, current->nsproxy->pid_ns) is nothing but a xxx_vnr(foo) one. Switch all the xxx_nr_ns() callers to use the xxx_vnr() calls where appropriate. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Reviewed-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06taskstats scaled time cleanupMichael Neuling
This moves the ability to scale cputime into generic code. This allows us to fix the issue in kernel/timer.c (noticed by Balbir) where we could only add an unscaled value to the scaled utime/stime. This adds a cputime_to_scaled function. As before, the POWERPC version does the scaling based on the last SPURR/PURR ratio calculated. The generic and s390 (only other arch to implement asm/cputime.h) versions are both NOPs. Also moves the SPURR and PURR snapshots closer. Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-01Merge branch 'task_killable' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc * 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits) Remove commented-out code copied from NFS NFS: Switch from intr mount option to TASK_KILLABLE Add wait_for_completion_killable Add wait_event_killable Add schedule_timeout_killable Use mutex_lock_killable in vfs_readdir Add mutex_lock_killable Use lock_page_killable Add lock_page_killable Add fatal_signal_pending Add TASK_WAKEKILL exit: Use task_is_* signal: Use task_is_* sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL ptrace: Use task_is_* power: Use task_is_* wait: Use TASK_NORMAL proc/base.c: Use task_is_* proc/array.c: Use TASK_REPORT perfmon: Use task_is_* ... Fixed up conflicts in NFS/sunrpc manually..
2008-01-30time: timer cleanupsPavel Machek
Small cleanups to tick-related code. Wrong preempt count is followed by BUG(), so it is hardly KERN_WARNING. Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30time: clean hungarian notation from timersPavel Machek
Clean up hungarian notation from timer code. Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-25hrtimer: fixup the HRTIMER_CB_IRQSAFE_NO_SOFTIRQ fallbackPeter Zijlstra
Currently all highres=off timers are run from softirq context, but HRTIMER_CB_IRQSAFE_NO_SOFTIRQ timers expect to run from irq context. Fix this up by splitting it similar to the highres=on case. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-21timer: fix section mismatchRandy Dunlap
The caller is __cpuinit. Also, this code block and its caller are inside #ifdef CONFIG_HOTPLUG_CPU blocks, so this code should reflect that config symbol's usage. WARNING: vmlinux.o(.text+0x4252f): Section mismatch: reference to .init.text: (between 'timer_cpu_notify' and 'msleep') Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@akpm@linux-foundation.org>
2008-01-13remove task_ppid_nr_nsRoland McGrath
task_ppid_nr_ns is called in three places. One of these should never have called it. In the other two, using it broke the existing semantics. This was presumably accidental. If the function had not been there, it would have been much more obvious to the eye that those patches were changing the behavior. We don't need this function. In task_state, the pid of the ptracer is not the ppid of the ptracer. In do_task_stat, ppid is the tgid of the real_parent, not its pid. I also moved the call outside of lock_task_sighand, since it doesn't need it. In sys_getppid, ppid is the tgid of the real_parent, not its pid. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-18timer: kernel/timer.c section fixesAdrian Bunk
This patch fixes the following section mismatches with CONFIG_HOTPLUG=n, CONFIG_HOTPLUG_CPU=y: ... WARNING: vmlinux.o(.text+0x41cd3): Section mismatch: reference to .init.data:tvec_base_done.22610 (between 'timer_cpu_notify' and 'run_timer_softirq') WARNING: vmlinux.o(.text+0x41d67): Section mismatch: reference to .init.data:tvec_base_done.22610 (between 'timer_cpu_notify' and 'run_timer_softirq') ... Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-12-06Add schedule_timeout_killableMatthew Wilcox
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2007-11-09sched: restore deterministic CPU accounting on powerpcPaul Mackerras
Since powerpc started using CONFIG_GENERIC_CLOCKEVENTS, the deterministic CPU accounting (CONFIG_VIRT_CPU_ACCOUNTING) has been broken on powerpc, because we end up counting user time twice: once in timer_interrupt() and once in update_process_times(). This fixes the problem by pulling the code in update_process_times that updates utime and stime into a separate function called account_process_tick. If CONFIG_VIRT_CPU_ACCOUNTING is not defined, there is a version of account_process_tick in kernel/timer.c that simply accounts a whole tick to either utime or stime as before. If CONFIG_VIRT_CPU_ACCOUNTING is defined, then arch code gets to implement account_process_tick. This also lets us simplify the s390 code a bit; it means that the s390 timer interrupt can now call update_process_times even when CONFIG_VIRT_CPU_ACCOUNTING is turned on, and can just implement a suitable account_process_tick(). account_process_tick() now takes the task_struct * as an argument. Tested both with and without CONFIG_VIRT_CPU_ACCOUNTING. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-05time: fix inconsistent function names in commentsLi Zefan
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19pid namespaces: changes to show virtual ids to userPavel Emelyanov
This is the largest patch in the set. Make all (I hope) the places where the pid is shown to or get from user operate on the virtual pids. The idea is: - all in-kernel data structures must store either struct pid itself or the pid's global nr, obtained with pid_nr() call; - when seeking the task from kernel code with the stored id one should use find_task_by_pid() call that works with global pids; - when showing pid's numerical value to the user the virtual one should be used, but however when one shows task's pid outside this task's namespace the global one is to be used; - when getting the pid from userspace one need to consider this as the virtual one and use appropriate task/pid-searching functions. [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: nuther build fix] [akpm@linux-foundation.org: yet nuther build fix] [akpm@linux-foundation.org: remove unneeded casts] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Paul Menage <menage@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18Add scaled time to taskstats based process accountingMichael Neuling
This adds items to the taststats struct to account for user and system time based on scaling the CPU frequency and instruction issue rates. Adds account_(user|system)_time_scaled callbacks which architectures can use to account for time using this mechanism. Signed-off-by: Michael Neuling <mikey@neuling.org> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18whitespace fixes: system timersDaniel Walker
Signed-off-by: Daniel Walker <dwalker@mvista.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-20Pull ia64-clocksource into release branchTony Luck
2007-07-20[IA64] remove time interpolatorBob Picco
Remove time_interpolator code (This is generic code, but only user was ia64. It has been superseded by the CONFIG_GENERIC_TIME code). Signed-off-by: Bob Picco <bob.picco@hp.com> Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Peter Keilty <peter.keilty@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-07-19timer.c: cleanup recently introduced whitespace damageThomas Gleixner
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17Slab allocators: Replace explicit zeroing with __GFP_ZEROChristoph Lameter
kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing variant in the past. But with __GFP_ZERO it is possible now to do zeroing while allocating. Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever we can. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16Add a flag to indicate deferrable timers in /proc/timer_statsVenki Pallipadi
Add a flag in /proc/timer_stats to indicate deferrable timers. This will let developers/users to differentiate between types of tiemrs in /proc/timer_stats. Deferrable timer and normal timer will appear in /proc/timer_stats as below. 10D, 1 swapper queue_delayed_work_on (delayed_work_timer_fn) 10, 1 swapper queue_delayed_work_on (delayed_work_timer_fn) Also version of timer_stats changes from v0.1 to v0.2 Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16Use boot based time for uptime in /procTomas Janousek
Commit 411187fb05cd11676b0979d9fbf3291db69dbce2 caused uptime not to increase during suspend. This may cause confusion so I restore the old behaviour by using the boot based time instead of monotonic for uptime. Signed-off-by: Tomas Janousek <tjanouse@redhat.com> Acked-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-29NOHZ: prevent multiplication overflow - stop timer for huge timeoutsThomas Gleixner
get_next_timer_interrupt() returns a delta of (LONG_MAX > 1) in case there is no timer pending. On 64 bit machines this results in a multiplication overflow in tick_nohz_stop_sched_tick(). Reported by: Dave Miller <davem@davemloft.net> Make the return value a constant and limit the return value to a 32 bit value. When the max timeout value is returned, we can safely stop the tick timer device. The max jiffies delta results in a 12 days timeout for HZ=1000. In the long term the get_next_timer_interrupt() code needs to be reworked to return ktime instead of jiffies, but we have to wait until the last users of the original NO_IDLE_HZ code are converted. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-14timekeeping fix patch got mis-appliedThomas Gleixner
The time keeping code move to kernel/time/timekeeping.c broke the clocksource resume logic patch, which got applied to the old file by a fuzzy application. Fix it up and move the clocksource_resume() call to the appropriate place. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [ tssk, tssk, everybody should use --fuzz=0 ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-10timer: revert parenthesis fix in tbase_get_deferrable() etcakpm@linux-foundation.org
On 09-05-2007 21:10, Pallipadi, Venkatesh wrote: ... > On a 64 bit system, converting pointer to int causes unnecessary > compiler warning, and intermediate long conversion was to avoid that. > I will have to rephrase my comment to remove 32 bit value and use int, > as that is what the function returns. So, this patch reverts all changes done by my previous patch. I apologize for my wrong comment about "logical error" here. Cc: "Pallipadi, Venkatesh" <venkatesh.pallipadi@intel.com> Cc: Satyam Sharma <satyam.sharma@gmail.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Jarek Poplawski <jarkao2@o2.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09clocksource: fix resume logicThomas Gleixner
We need to make sure that the clocksources are resumed, when timekeeping is resumed. The current resume logic does not guarantee this. Add a resume function pointer to the clocksource struct, so clocksource drivers which need to reinitialize the clocksource can provide a resume function. Add a resume function, which calls the maybe available clocksource resume functions and resets the watchdog function, so a stable TSC can be used accross suspend/resume. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: john stultz <johnstul@us.ibm.com> Cc: Andi Kleen <ak@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09Add suspend-related notifications for CPU hotplugRafael J. Wysocki
Since nonboot CPUs are now disabled after tasks and devices have been frozen and the CPU hotplug infrastructure is used for this purpose, we need special CPU hotplug notifications that will help the CPU-hotplug-aware subsystems distinguish normal CPU hotplug events from CPU hotplug events related to a system-wide suspend or resume operation in progress. This patch introduces such notifications and causes them to be used during suspend and resume transitions. It also changes all of the CPU-hotplug-aware subsystems to take these notifications into consideration (for now they are handled in the same way as the corresponding "normal" ones). [oleg@tv-sign.ru: cleanups] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Gautham R Shenoy <ego@in.ibm.com> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09timer: parenthesis fix in tbase_get_deferrable() etcJarek Poplawski
Signed-off-by: Jarek Poplawski <jarkao2@o2.pl> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08Introduce a handy list_first_entry macroPavel Emelianov
There are many places in the kernel where the construction like foo = list_entry(head->next, struct foo_struct, list); are used. The code might look more descriptive and neat if using the macro list_first_entry(head, type, member) \ list_entry((head)->next, type, member) Here is the macro itself and the examples of its usage in the generic code. If it will turn out to be useful, I can prepare the set of patches to inject in into arch-specific code, drivers, networking, etc. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Signed-off-by: Kirill Korotaev <dev@openvz.org> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Zach Brown <zach.brown@oracle.com> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: john stultz <johnstul@us.ibm.com> Cc: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08Move timekeeping code to timekeeping.cjohn stultz
Move the timekeeping code out of kernel/timer.c and into kernel/time/timekeeping.c. I made no cleanups or other changes in transit. [akpm@linux-foundation.org: build fix] Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08Add support for deferrable timersVenki Pallipadi
Introduce a new flag for timers - deferrable: Timers that work normally when system is busy. But, will not cause CPU to come out of idle (just to service this timer), when CPU is idle. Instead, this timer will be serviced when CPU eventually wakes up with a subsequent non-deferrable timer. The main advantage of this is to avoid unnecessary timer interrupts when CPU is idle. If the routine currently called by a timer can wait until next event without any issues, this new timer can be used to setup timer event for that routine. This, with dynticks, allows CPUs to be lazy, allowing them to stay in idle for extended period of time by reducing unnecesary wakeup and thereby reducing the power consumption. This patch: Builds this new timer on top of existing timer infrastructure. It uses last bit in 'base' pointer of timer_list structure to store this deferrable timer flag. __next_timer_interrupt() function skips over these deferrable timers when CPU looks for next timer event for which it has to wake up. This is exported by a new interface init_timer_deferrable() that can be called in place of regular init_timer(). [akpm@linux-foundation.org: Privatise a #define] Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-26[AF_RXRPC]: Make it possible to merely try to cancel timers from a moduleDavid Howells
Export try_to_del_timer_sync() for use by the AF_RXRPC module. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-07[PATCH] high-res timers: resume fixIngo Molnar
Soeren Sonnenburg reported that upon resume he is getting this backtrace: [<c0119637>] smp_apic_timer_interrupt+0x57/0x90 [<c0142d30>] retrigger_next_event+0x0/0xb0 [<c0104d30>] apic_timer_interrupt+0x28/0x30 [<c0142d30>] retrigger_next_event+0x0/0xb0 [<c0140068>] __kfifo_put+0x8/0x90 [<c0130fe5>] on_each_cpu+0x35/0x60 [<c0143538>] clock_was_set+0x18/0x20 [<c0135cdc>] timekeeping_resume+0x7c/0xa0 [<c02aabe1>] __sysdev_resume+0x11/0x80 [<c02ab0c7>] sysdev_resume+0x47/0x80 [<c02b0b05>] device_power_up+0x5/0x10 it turns out that on resume we mistakenly re-enable interrupts too early. Do the timer retrigger only on the current CPU. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Soeren Sonnenburg <kernel@nn7.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-25[PATCH] dynticks: fix hrtimer rounding error in next_timer_interruptThomas Gleixner
The rework of next_timer_interrupt() fixed the timer wheel bugs, but invented a rounding error versus the next hrtimer event. This is caused by the conversion of the hrtimer internal representation to relative jiffies. This causes bug #8100: http://bugzilla.kernel.org/show_bug.cgi?id=8100 next_timer_interrupt() returns "now" in such a case and causes the code in tick_nohz_stop_sched_tick() to trigger the timer softirq, which is bogus as no timer is due for expiry. This results in an endless context switching between idle and ksoftirqd until a timer is due for expiry. Modify the hrtimer evaluation so that, it returns now + 1, when the conversion results in a delta < 1 jiffie. It's confirmed to resolve bug #8100 Reported-by: Emil Karlson <jkarlson@cc.hut.fi> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-06[PATCH] fix vsyscall settimeofdayDaniel Walker
I've only seen this on x86_64. The vsyscall state only gets updated when a timer interrupts comes in. So if the time is set long before the next timer, there will be a period when a gettimeofday() won't reflect the correct time. I added an explicit update_vsyscall() during the settimeofday(), that way the vsyscall state doesn't get stale. Signed-off-by: Daniel Walker <dwalker@mvista.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-06[PATCH] Save/restore periodic tick information over suspend/resumeThomas Gleixner
The programming of periodic tick devices needs to be saved/restored across suspend/resume - otherwise we might end up with a system coming up that relies on getting a PIT (or HPET) interrupt, while those devices default to 'no interrupts' after powerup. (To confuse things it worked to a certain degree on some systems because the lapic gets initialized as a side-effect of SMP bootup.) This suspend / resume thing was dropped unintentionally during the last-minute -mm code reshuffling. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-05[PATCH] timer/hrtimer: take per cpu locks in sane orderHeiko Carstens
Doing something like this on a two cpu system # echo 0 > /sys/devices/system/cpu/cpu0/online # echo 1 > /sys/devices/system/cpu/cpu0/online # echo 0 > /sys/devices/system/cpu/cpu1/online will give me this: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.21-rc2-g562aa1d4-dirty #7 ------------------------------------------------------- bash/1282 is trying to acquire lock: (&cpu_base->lock_key){.+..}, at: [<000000000005f17e>] hrtimer_cpu_notify+0xc6/0x240 but task is already holding lock: (&cpu_base->lock_key#2){.+..}, at: [<000000000005f174>] hrtimer_cpu_notify+0xbc/0x240 which lock already depends on the new lock. This happens because we have the following code in kernel/hrtimer.c: migrate_hrtimers(int cpu) [...] old_base = &per_cpu(hrtimer_bases, cpu); new_base = &get_cpu_var(hrtimer_bases); [...] spin_lock(&new_base->lock); spin_lock(&old_base->lock); Which means the spinlocks are taken in an order which depends on which cpu gets shut down from which other cpu. Therefore lockdep complains that there might be an ABBA deadlock. Since migrate_hrtimers() gets only called on cpu hotplug it's safe to assume that it isn't executed concurrently on a The same problem exists in kernel/timer.c: migrate_timers(). As pointed out by Christian Borntraeger one possible solution to avoid the locking order complaints would be to make sure that the locks are always taken in the same order. E.g. by taking the lock of the cpu with the lower number first. To achieve this we introduce two new spinlock functions double_spin_lock and double_spin_unlock which lock or unlock two locks in a given order. Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: John Stultz <johnstul@us.ibm.com> Cc: Christian Borntraeger <cborntra@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-01[PATCH] kernel-doc fixes for 2.6.20-git15 (non-drivers)Randy Dunlap
Fix kernel-doc warnings in 2.6.20-git15 (lib/, mm/, kernel/, include/). 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>
2007-03-01[PATCH] update timekeeping_is_continuous commentDaniel Walker
Signed-off-by: Daniel Walker <dwalker@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>