summaryrefslogtreecommitdiff
path: root/kernel
AgeCommit message (Collapse)Author
2011-09-15futex: uninitialized warning correctionsVitaliy Ivanov
The variables here are really not used uninitialized. kernel/futex.c: In function 'fixup_pi_state_owner.clone.17': kernel/futex.c:1582:6: warning: 'curval' may be used uninitialized in this function kernel/futex.c: In function 'handle_futex_death': kernel/futex.c:2486:6: warning: 'nval' may be used uninitialized in this function kernel/futex.c: In function 'do_futex': kernel/futex.c:863:11: warning: 'curval' may be used uninitialized in this function kernel/futex.c:828:6: note: 'curval' was declared here kernel/futex.c:898:5: warning: 'oldval' may be used uninitialized in this function kernel/futex.c:890:6: note: 'oldval' was declared here Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com> Acked-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-15async: uninitialized warning correctionsVitaliy Ivanov
The variables here are really not used uninitialized. kernel/async.c: In function 'async_synchronize_cookie_domain': kernel/async.c:270:10: warning: 'starttime.tv64' may be used uninitialized in this function kernel/async.c: In function 'async_run_entry_fn': kernel/async.c:122:10: warning: 'calltime.tv64' may be used uninitialized in this function Signed-off-by: Vitaliy Ivanov <vitalivanov@gmail.com> Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-14workqueue: lock cwq access in drain_workqueueThomas Tuttle
Take cwq->gcwq->lock to avoid racing between drain_workqueue checking to make sure the workqueues are empty and cwq_dec_nr_in_flight decrementing and then incrementing nr_active when it activates a delayed work. We discovered this when a corner case in one of our drivers resulted in us trying to destroy a workqueue in which the remaining work would always requeue itself again in the same workqueue. We would hit this race condition and trip the BUG_ON on workqueue.c:3080. Signed-off-by: Thomas Tuttle <ttuttle@chromium.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-14alarmtimers: Fix error handlingThomas Gleixner
commit 8bc0daf (alarmtimers: Rework RTC device selection using class interface) did not implement required error checks. Add them. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-13locking, latencytop: Annotate latency_lock as rawThomas Gleixner
The latency_lock is lock can be taken in the guts of the scheduler code and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, timer_stats: Annotate table_lock as rawThomas Gleixner
The table_lock lock can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Reported-by: Andreas Sundebo <kernel@sundebo.dk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Andreas Sundebo <kernel@sundebo.dk> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, semaphores: Annotate inner lock as rawThomas Gleixner
There is no reason to have the spin_lock protecting the semaphore preemptible on -rt. Annotate it as a raw_spinlock. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. ( On rt this also solves lockdep complaining about the rt_mutex.wait_lock being not initialized. ) Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, sched: Annotate thread_group_cputimer as rawThomas Gleixner
The thread_group_cputimer lock can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, printk: Annotate logbuf_lock as rawThomas Gleixner
The logbuf_lock lock can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> [ merged and fixed it ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, tracing: Annotate tracing locks as rawThomas Gleixner
The tracing locks can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, sched, cgroups: Annotate release_list_lock as rawThomas Gleixner
The release_list_lock can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13locking, kprobes: Annotate the hash locks and kretprobe.lock as rawThomas Gleixner
The kprobe locks can be taken in atomic context and therefore cannot be preempted on -rt - annotate it. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-13clocksource: Make watchdog reset locklessThomas Gleixner
KGDB needs to trylock watchdog_lock when trying to reset the clocksource watchdog after the system has been stopped to avoid a potential deadlock. When the trylock fails TSC usually becomes unstable. We can be more clever by using an atomic counter and checking it in the clocksource_watchdog callback. We restart the watchdog whenever the counter is > 0 and only decrement the counter when we ran through a full update cycle. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <johnstul@us.ibm.com> Acked-by: Jason Wessel <jason.wessel@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1109121326280.2723@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-12rtmutex: Cleanup the debug codeThomas Gleixner
Use the existing lock debugging macros. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-12genirq: Add IRQCHIP_SKIP_SET_WAKE flagSantosh Shilimkar
Some irq chips need the irq_set_wake() functionality, but do not require a irq_set_wake() callback. Instead of forcing an empty callback to be implemented add a flag which notes this fact. Check for the flag in set_irq_wake_real() and return success when set. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Thomas Gleixner <tglx@linutronix.de>
2011-09-12genirq: Make irq_shutdown() symmetric vs. irq_startup againGeert Uytterhoeven
If an irq_chip provides .irq_shutdown(), but neither of .irq_disable() or .irq_mask(), free_irq() crashes when jumping to NULL. Fix this by only trying .irq_disable() and .irq_mask() if there's no .irq_shutdown() provided. This revives the symmetry with irq_startup(), which tries .irq_startup(), .irq_enable(), and irq_unmask(), and makes it consistent with the comment for irq_chip.irq_shutdown() in <linux/irq.h>, which says: * @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL) This is also how __free_irq() behaved before the big overhaul, cfr. e.g. 3b56f0585fd4c02d047dc406668cb40159b2d340 ("genirq: Remove bogus conditional"), where the core interrupt code always overrode .irq_shutdown() to .irq_disable() if .irq_shutdown() was NULL. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: linux-m68k@lists.linux-m68k.org Link: http://lkml.kernel.org/r/1315742394-16036-2-git-send-email-geert@linux-m68k.org Cc: stable@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-08posix-cpu-timers: Cure SMP accounting odditiesPeter Zijlstra
David reported: Attached below is a watered-down version of rt/tst-cpuclock2.c from GLIBC. Just build it with "gcc -o test test.c -lpthread -lrt" or similar. Run it several times, and you will see cases where the main thread will measure a process clock difference before and after the nanosleep which is smaller than the cpu-burner thread's individual thread clock difference. This doesn't make any sense since the cpu-burner thread is part of the top-level process's thread group. I've reproduced this on both x86-64 and sparc64 (using both 32-bit and 64-bit binaries). For example: [davem@boricha build-x86_64-linux]$ ./test process: before(0.001221967) after(0.498624371) diff(497402404) thread: before(0.000081692) after(0.498316431) diff(498234739) self: before(0.001223521) after(0.001240219) diff(16698) [davem@boricha build-x86_64-linux]$ The diff of 'process' should always be >= the diff of 'thread'. I make sure to wrap the 'thread' clock measurements the most tightly around the nanosleep() call, and that the 'process' clock measurements are the outer-most ones. --- #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <time.h> #include <fcntl.h> #include <string.h> #include <errno.h> #include <pthread.h> static pthread_barrier_t barrier; static void *chew_cpu(void *arg) { pthread_barrier_wait(&barrier); while (1) __asm__ __volatile__("" : : : "memory"); return NULL; } int main(void) { clockid_t process_clock, my_thread_clock, th_clock; struct timespec process_before, process_after; struct timespec me_before, me_after; struct timespec th_before, th_after; struct timespec sleeptime; unsigned long diff; pthread_t th; int err; err = clock_getcpuclockid(0, &process_clock); if (err) return 1; err = pthread_getcpuclockid(pthread_self(), &my_thread_clock); if (err) return 1; pthread_barrier_init(&barrier, NULL, 2); err = pthread_create(&th, NULL, chew_cpu, NULL); if (err) return 1; err = pthread_getcpuclockid(th, &th_clock); if (err) return 1; pthread_barrier_wait(&barrier); err = clock_gettime(process_clock, &process_before); if (err) return 1; err = clock_gettime(my_thread_clock, &me_before); if (err) return 1; err = clock_gettime(th_clock, &th_before); if (err) return 1; sleeptime.tv_sec = 0; sleeptime.tv_nsec = 500000000; nanosleep(&sleeptime, NULL); err = clock_gettime(th_clock, &th_after); if (err) return 1; err = clock_gettime(my_thread_clock, &me_after); if (err) return 1; err = clock_gettime(process_clock, &process_after); if (err) return 1; diff = process_after.tv_nsec - process_before.tv_nsec; printf("process: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n", process_before.tv_sec, process_before.tv_nsec, process_after.tv_sec, process_after.tv_nsec, diff); diff = th_after.tv_nsec - th_before.tv_nsec; printf("thread: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n", th_before.tv_sec, th_before.tv_nsec, th_after.tv_sec, th_after.tv_nsec, diff); diff = me_after.tv_nsec - me_before.tv_nsec; printf("self: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n", me_before.tv_sec, me_before.tv_nsec, me_after.tv_sec, me_after.tv_nsec, diff); return 0; } This is due to us using p->se.sum_exec_runtime in thread_group_cputime() where we iterate the thread group and sum all data. This does not take time since the last schedule operation (tick or otherwise) into account. We can cure this by using task_sched_runtime() at the cost of having to take locks. This also means we can (and must) do away with thread_group_sched_runtime() since the modified thread_group_cputime() is now more accurate and would deadlock when called from thread_group_sched_runtime(). Reported-by: David Miller <davem@davemloft.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1314874459.7945.22.camel@twins Cc: stable@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-08clockevents: Add direct ktime programming functionMartin Schwidefsky
There is at least one architecture (s390) with a sane clockevent device that can be programmed with the equivalent of a ktime. No need to create a delta against the current time, the ktime can be used directly. A new clock device function 'set_next_ktime' is introduced that is called with the unmodified ktime for the timer if the clock event device has the CLOCK_EVT_FEAT_KTIME bit set. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: john stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/20110823133142.815350967@de.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-08clockevents: Make minimum delay adjustments configurableMartin Schwidefsky
The automatic increase of the min_delta_ns of a clockevents device should be done in the clockevents code as the minimum delay is an attribute of the clockevents device. In addition not all architectures want the automatic adjustment, on a massively virtualized system it can happen that the programming of a clock event fails several times in a row because the virtual cpu has been rescheduled quickly enough. In that case the minimum delay will erroneously be increased with no way back. The new config symbol GENERIC_CLOCKEVENTS_MIN_ADJUST is used to enable the automatic adjustment. The config option is selected only for x86. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: john stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/20110823133142.494157493@de.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-08nohz: Remove "Switched to NOHz mode" debugging messagesHeiko Carstens
When performing cpu hotplug tests the kernel printk log buffer gets flooded with pointless "Switched to NOHz mode..." messages. Especially when afterwards analyzing a dump this might have removed more interesting stuff out of the buffer. Assuming that switching to NOHz mode simply works just remove the printk. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Link: http://lkml.kernel.org/r/20110823112046.GB2540@osiris.boeblingen.de.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-08nohz: Make idle/iowait counter update conditionalMichal Hocko
get_cpu_{idle,iowait}_time_us update idle/iowait counters unconditionally if the given CPU is in the idle loop. This doesn't work well outside of CPU governors which are singletons so nobody (except for IRQ) can race with them. We will need to use both functions from /proc/stat handler to properly handle nohz idle/iowait times. Make the update depend on a non NULL last_update_time argument. Signed-off-by: Michal Hocko <mhocko@suse.cz> Cc: Dave Jones <davej@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alexey Dobriyan <adobriyan@gmail.com> Link: http://lkml.kernel.org/r/11f23179472635ce52e78921d47a20216b872f23.1314172057.git.mhocko@suse.cz Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-08nohz: Fix update_ts_time_stat idle accountingMichal Hocko
update_ts_time_stat currently updates idle time even if we are in iowait loop at the moment. The only real users of the idle counter (via get_cpu_idle_time_us) are CPU governors and they expect to get cumulative time for both idle and iowait times. The value (idle_sleeptime) is also printed to userspace by print_cpu but it prints both idle and iowait times so the idle part is misleading. Let's clean this up and fix update_ts_time_stat to account both counters properly and update consumers of idle to consider iowait time as well. If we do this we might use get_cpu_{idle,iowait}_time_us from other contexts as well and we will get expected values. Signed-off-by: Michal Hocko <mhocko@suse.cz> Cc: Dave Jones <davej@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alexey Dobriyan <adobriyan@gmail.com> Link: http://lkml.kernel.org/r/e9c909c221a8da402c4da07e4cd968c3218f8eb1.1314172057.git.mhocko@suse.cz Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-07Merge branch 'timers-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tipLinus Torvalds
* 'timers-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip: rtc: twl: Fix registration vs. init order rtc: Initialized rtc_time->tm_isdst rtc: Fix RTC PIE frequency limit rtc: rtc-twl: Remove lockdep related local_irq_enable() rtc: rtc-twl: Switch to using threaded irq rtc: ep93xx: Fix 'rtc' may be used uninitialized warning alarmtimers: Avoid possible denial of service with high freq periodic timers alarmtimers: Memset itimerspec passed into alarm_timer_get alarmtimers: Avoid possible null pointer traversal
2011-09-07Merge branch 'sched-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tipLinus Torvalds
* 'sched-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip: sched: Fix a memory leak in __sdt_free() sched: Move blk_schedule_flush_plug() out of __schedule() sched: Separate the scheduler entry for preemption
2011-08-31perf_event: Fix broken calc_timer_values()Eric B Munson
We detected a serious issue with PERF_SAMPLE_READ and timing information when events were being multiplexing. Samples would have time_running > time_enabled. That was easy to reproduce with a libpfm4 example (ran 3 times to cause multiplexing on Core 2): $ syst_smpl -e uops_retired:freq=1 & $ syst_smpl -e uops_retired:freq=1 & $ syst_smpl -e uops_retired:freq=1 & IIP:0x0000000040062d ... PERIOD:2355332948 ENA=40144625315 RUN=60014875184 syst_smpl: WARNING: time_running > time_enabled 63277537998 uops_retired:freq=1 , scaled The bug was not present in kernel up to (and including) 3.0. It turns out the bug was introduced by the following commit: commit c4794295917ebeda8013b6cb9c8d71ab4f74a1fa events: Move lockless timer calculation into helper function The parameters of the function got reversed yet the call sites were not updated to reflect the change. That lead to time_running and time_enabled being swapped. That had no effect when there was no multiplexing because in that case time_running = time_enabled but it would show up in any other scenario. Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110829124112.GA4828@quad Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-31perf: provide PMU when initing eventsMark Rutland
Currently, an event's 'pmu' field is set after pmu::event_init() is called. This means that pmu::event_init() must figure out which struct pmu the event was initialised from. This makes it difficult to consolidate common event initialisation code for similar PMUs, and very difficult to implement drivers for PMUs which can have multiple instances (e.g. a USB controller PMU, a GPU PMU, etc). This patch sets the 'pmu' field before initialising the event, allowing event init code to identify the struct pmu instance easily. In the event of failure to initialise an event, the event is destroyed via kfree() without calling perf_event::destroy(), so this shouldn't result in bad behaviour even if the destroy field was set before failure to initialise was noted. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1313062280-19123-1-git-send-email-mark.rutland@arm.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-30trace: Add ring buffer stats to measure rate of eventsVaibhav Nagarnaik
The stats file under per_cpu folder provides the number of entries, overruns and other statistics about the CPU ring buffer. However, the numbers do not provide any indication of how full the ring buffer is in bytes compared to the overall size in bytes. Also, it is helpful to know the rate at which the cpu buffer is filling up. This patch adds an entry "bytes: " in printed stats for per_cpu ring buffer which provides the actual bytes consumed in the ring buffer. This field includes the number of bytes used by recorded events and the padding bytes added when moving the tail pointer to next page. It also adds the following time stamps: "oldest event ts:" - the oldest timestamp in the ring buffer "now ts:" - the timestamp at the time of reading The field "now ts" provides a consistent time snapshot to the userspace when being read. This is read from the same trace clock used by tracing event timestamps. Together, these values provide the rate at which the buffer is filling up, from the formula: bytes / (now_ts - oldest_event_ts) Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: Michael Rubin <mrubin@google.com> Cc: David Sharp <dhsharp@google.com> Link: http://lkml.kernel.org/r/1313531179-9323-3-git-send-email-vnagarnaik@google.com Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-08-30trace: Add a new readonly entry to report total buffer sizeVaibhav Nagarnaik
The current file "buffer_size_kb" reports the size of per-cpu buffer and not the overall memory allocated which could be misleading. A new file "buffer_total_size_kb" adds up all the enabled CPU buffer sizes and reports it. This is only a readonly entry. Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Cc: Michael Rubin <mrubin@google.com> Cc: David Sharp <dhsharp@google.com> Link: http://lkml.kernel.org/r/1313531179-9323-2-git-send-email-vnagarnaik@google.com Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-08-30tracing: Add preempt disable for filter self testSteven Rostedt
The self testing for event filters does not really need preemption disabled as there are no races at the time of testing, but the functions it calls uses rcu_dereference_sched() which will complain if preemption is not disabled. Cc: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-08-29perf events: Fix slow and broken cgroup context switch codeStephane Eranian
The current cgroup context switch code was incorrect leading to bogus counts. Furthermore, as soon as there was an active cgroup event on a CPU, the context switch cost on that CPU would increase by a significant amount as demonstrated by a simple ping/pong example: $ ./pong Both processes pinned to CPU1, running for 10s 10684.51 ctxsw/s Now start a cgroup perf stat: $ perf stat -e cycles,cycles -A -a -G test -C 1 -- sleep 100 $ ./pong Both processes pinned to CPU1, running for 10s 6674.61 ctxsw/s That's a 37% penalty. Note that pong is not even in the monitored cgroup. The results shown by perf stat are bogus: $ perf stat -e cycles,cycles -A -a -G test -C 1 -- sleep 100 Performance counter stats for 'sleep 100': CPU1 <not counted> cycles test CPU1 16,984,189,138 cycles # 0.000 GHz The second 'cycles' event should report a count @ CPU clock (here 2.4GHz) as it is counting across all cgroups. The patch below fixes the bogus accounting and bypasses any cgroup switches in case the outgoing and incoming tasks are in the same cgroup. With this patch the same test now yields: $ ./pong Both processes pinned to CPU1, running for 10s 10775.30 ctxsw/s Start perf stat with cgroup: $ perf stat -e cycles,cycles -A -a -G test -C 1 -- sleep 10 Run pong outside the cgroup: $ /pong Both processes pinned to CPU1, running for 10s 10687.80 ctxsw/s The penalty is now less than 2%. And the results for perf stat are correct: $ perf stat -e cycles,cycles -A -a -G test -C 1 -- sleep 10 Performance counter stats for 'sleep 10': CPU1 <not counted> cycles test # 0.000 GHz CPU1 23,933,981,448 cycles # 0.000 GHz Now perf stat reports the correct counts for for the non cgroup event. If we run pong inside the cgroup, then we also get the correct counts: $ perf stat -e cycles,cycles -A -a -G test -C 1 -- sleep 10 Performance counter stats for 'sleep 10': CPU1 22,297,726,205 cycles test # 0.000 GHz CPU1 23,933,981,448 cycles # 0.000 GHz 10.001457237 seconds time elapsed Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110825135803.GA4697@quad Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-29sched: Fix a memory leak in __sdt_free()WANG Cong
This patch fixes the following memory leak: unreferenced object 0xffff880107266800 (size 512): comm "sched-powersave", pid 3718, jiffies 4323097853 (age 27495.450s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff81133940>] create_object+0x187/0x28b [<ffffffff814ac103>] kmemleak_alloc+0x73/0x98 [<ffffffff811232ba>] __kmalloc_node+0x104/0x159 [<ffffffff81044b98>] kzalloc_node.clone.97+0x15/0x17 [<ffffffff8104cb90>] build_sched_domains+0xb7/0x7f3 [<ffffffff8104d4df>] partition_sched_domains+0x1db/0x24a [<ffffffff8109ee4a>] do_rebuild_sched_domains+0x3b/0x47 [<ffffffff810a00c7>] rebuild_sched_domains+0x10/0x12 [<ffffffff8104d5ba>] sched_power_savings_store+0x6c/0x7b [<ffffffff8104d5df>] sched_mc_power_savings_store+0x16/0x18 [<ffffffff8131322c>] sysdev_class_store+0x20/0x22 [<ffffffff81193876>] sysfs_write_file+0x108/0x144 [<ffffffff81135b10>] vfs_write+0xaf/0x102 [<ffffffff81135d23>] sys_write+0x4d/0x74 [<ffffffff814c8a42>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff Signed-off-by: WANG Cong <amwang@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: stable@kernel.org # 3.0 Link: http://lkml.kernel.org/r/1313671017-4112-1-git-send-email-amwang@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-29sched: Move blk_schedule_flush_plug() out of __schedule()Thomas Gleixner
There is no real reason to run blk_schedule_flush_plug() with interrupts and preemption disabled. Move it into schedule() and call it when the task is going voluntarily to sleep. There might be false positives when the task is woken between that call and actually scheduling, but that's not really different from being woken immediately after switching away. This fixes a deadlock in the scheduler where the blk_schedule_flush_plug() callchain enables interrupts and thereby allows a wakeup to happen of the task that's going to sleep. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: stable@kernel.org # 2.6.39+ Link: http://lkml.kernel.org/n/tip-dwfxtra7yg1b5r65m32ywtct@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-29sched: Separate the scheduler entry for preemptionThomas Gleixner
Block-IO and workqueues call into notifier functions from the scheduler core code with interrupts and preemption disabled. These calls should be made before entering the scheduler core. To simplify this, separate the scheduler core code into __schedule(). __schedule() is directly called from the places which set PREEMPT_ACTIVE and from schedule(). This allows us to add the work checks into schedule(), so they are only called when a task voluntary goes to sleep. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: stable@kernel.org # 2.6.39+ Link: http://lkml.kernel.org/r/20110622174918.813258321@linutronix.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-26All Arch: remove linkage for sys_nfsservctl system callNeilBrown
The nfsservctl system call is now gone, so we should remove all linkage for it. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25kernel/printk: do not turn off bootconsole in printk_late_init() if keep_bootconNishanth Aravamudan
It seems that 7bf693951a8e ("console: allow to retain boot console via boot option keep_bootcon") doesn't always achieve what it aims, as when printk_late_init() runs it unconditionally turns off all boot consoles. With this patch, I am able to see more messages on the boot console in KVM guests than I can without, when keep_bootcon is specified. I think it is appropriate for the relevant -stable trees. However, it's more of an annoyance than a serious bug (ideally you don't need to keep the boot console around as console handover should be working -- I was encountering a situation where the console handover wasn't working and not having the boot console available meant I couldn't see why). Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com> Cc: David S. Miller <davem@davemloft.net> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Greg KH <gregkh@suse.de> Acked-by: Fabio M. Di Nitto <fdinitto@redhat.com> Cc: <stable@kernel.org> [2.6.39.x, 3.0.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25Add a personality to report 2.6.x version numbersAndi Kleen
I ran into a couple of programs which broke with the new Linux 3.0 version. Some of those were binary only. I tried to use LD_PRELOAD to work around it, but it was quite difficult and in one case impossible because of a mix of 32bit and 64bit executables. For example, all kind of management software from HP doesnt work, unless we pretend to run a 2.6 kernel. $ uname -a Linux svivoipvnx001 3.0.0-08107-g97cd98f #1062 SMP Fri Aug 12 18:11:45 CEST 2011 i686 i686 i386 GNU/Linux $ hpacucli ctrl all show Error: No controllers detected. $ rpm -qf /usr/sbin/hpacucli hpacucli-8.75-12.0 Another notable case is that Python now reports "linux3" from sys.platform(); which in turn can break things that were checking sys.platform() == "linux2": https://bugzilla.mozilla.org/show_bug.cgi?id=664564 It seems pretty clear to me though it's a bug in the apps that are using '==' instead of .startswith(), but this allows us to unbreak broken programs. This patch adds a UNAME26 personality that makes the kernel report a 2.6.40+x version number instead. The x is the x in 3.x. I know this is somewhat ugly, but I didn't find a better workaround, and compatibility to existing programs is important. Some programs also read /proc/sys/kernel/osrelease. This can be worked around in user space with mount --bind (and a mount namespace) To use: wget ftp://ftp.kernel.org/pub/linux/kernel/people/ak/uname26/uname26.c gcc -o uname26 uname26.c ./uname26 program Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25PM QoS: Add global notification mechanism for device constraintsJean Pihet
Add a global notification chain that gets called upon changes to the aggregated constraint value for any device. The notification callbacks are passing the full constraint request data in order for the callees to have access to it. The current use is for the platform low-level code to access the target device of the constraint. Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM QoS: Generalize and export constraints management codeJean Pihet
In preparation for the per-device constratins support: - rename update_target to pm_qos_update_target - generalize and export pm_qos_update_target for usage by the upcoming per-device latency constraints framework: * operate on struct pm_qos_constraints for constraints management, * introduce an 'action' parameter for constraints add/update/remove, * the return value indicates if the aggregated constraint value has changed, - update the internal code to operate on struct pm_qos_constraints - add a NULL pointer check in the API functions Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM QoS: Reorganize data structsJean Pihet
In preparation for the per-device constratins support, re-organize the data strctures: - add a struct pm_qos_constraints which contains the constraints related data - update struct pm_qos_object contents to the PM QoS internal object data. Add a pointer to struct pm_qos_constraints - update the internal code to use the new data structs. Signed-off-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM QoS: Code reorganizationJean Pihet
Move around the PM QoS misc devices management code for better readability. Signed-off-by: Jean Pihet <j-pihet@ti.com> Acked-by: markgross <markgross@thegnar.org> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM QoS: Minor clean-upsJean Pihet
- Misc fixes to improve code readability: * rename struct pm_qos_request_list to struct pm_qos_request, * rename pm_qos_req parameter to req in internal code, consistenly use req in the API parameters, * update the in-kernel API callers to the new parameters names, * rename of fields names (requests, list, node, constraints) Signed-off-by: Jean Pihet <j-pihet@ti.com> Acked-by: markgross <markgross@thegnar.org> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-25PM QoS: Move and rename the implementation filesJean Pihet
The PM QoS implementation files are better named kernel/power/qos.c and include/linux/pm_qos.h. The PM QoS support is compiled under the CONFIG_PM option. Signed-off-by: Jean Pihet <j-pihet@ti.com> Acked-by: markgross <markgross@thegnar.org> Reviewed-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-08-23Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: fix tracing builds inside the source tree xfs: remove subdirectories xfs: don't expect xfs headers to be in subdirectories
2011-08-23Revert "irq: Always set IRQF_ONESHOT if no primary handler is specified"Linus Torvalds
This reverts commit f3637a5f2e2eb391ff5757bc83fb5de8f9726464. It turns out that this breaks several drivers, one example being OMAP boards which use the on-board OMAP UARTs and the omap-serial driver that will not boot to userspace after the commit. Paul Walmsley reports that enabling CONFIG_DEBUG_SHIRQ reveals 'IRQ handler type mismatch' errors: IRQ handler type mismatch for IRQ 74 current handler: serial idle ... and the reason is that setting IRQF_ONESHOT will now result in those interrupt handlers having different IRQF flags, and thus being unsharable. So the commit log in the reverted commit: "Since it is required for those users and there is no difference for others it makes sense to add this flag unconditionally." is simply not true: there may not be any difference from a "actions at irq time", but there is a *big* difference wrt this flag testing irq management (see __setup_irq() in kernel/irq/manage.c). One solution may be to stop verifying IRQF_ONESHOT in __setup_irq(), but right now the safe course of action is to revert the change. Let's revisit this in a later merge window. Reported-by: Paul Walmsley <paul@pwsan.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Requested-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-23CRED: fix build error due to 'tgcred' undeclaredAxel Lin
This patch adds CONFIG_KEYS guard for tgcred to fix below build error if CONFIG_KEYS is not configured. CC kernel/cred.o kernel/cred.c: In function 'prepare_kernel_cred': kernel/cred.c:657: error: 'tgcred' undeclared (first use in this function) kernel/cred.c:657: error: (Each undeclared identifier is reported only once kernel/cred.c:657: error: for each function it appears in.) make[1]: *** [kernel/cred.o] Error 1 make: *** [kernel] Error 2 Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23CRED: Fix prepare_kernel_cred() to provide a new thread_group_cred structDavid Howells
Fix prepare_kernel_cred() to provide a new, separate thread_group_cred struct otherwise when using request_key() ____call_usermodehelper() calls umh_keys_init() with the new creds pointing to init_tgcred, which umh_keys_init() then blithely alters. The problem can be demonstrated by: # keyctl request2 user a debug:a @s 249681132 # grep req /proc/keys 079906a5 I--Q-- 1 perm 1f3f0000 0 0 keyring _req.249681132: 1/4 38ef1626 IR---- 1 expd 0b010000 0 0 .request_ key:ee1d4ec pid:4371 ci:1 The keyring _req.XXXX should have gone away, but something (init_tgcred) is pinning it. That key actually requested can then be removed and a new one created: # keyctl unlink 249681132 1 links removed [root@andromeda ~]# grep req /proc/keys 116cecac IR---- 1 expd 0b010000 0 0 .request_ key:eeb4911 pid:4379 ci:1 36d1cbf8 I--Q-- 1 perm 1f3f0000 0 0 keyring _req.250300689: 1/4 which causes the old _req keyring to go away and a new one to take its place. This is a consequence of the changes in: commit 879669961b11e7f40b518784863a259f735a72bf Author: David Howells <dhowells@redhat.com> Date: Fri Jun 17 11:25:59 2011 +0100 KEYS/DNS: Fix ____call_usermodehelper() to not lose the session keyring and: commit 17f60a7da150fdd0cfb9756f86a262daa72c835f Author: Eric Paris <eparis@redhat.com> Date: Fri Apr 1 17:07:50 2011 -0400 capabilites: allow the application of capability limits to usermode helpers After this patch is applied, the _req keyring and the .request_key key are cleaned up. Signed-off-by: David Howells <dhowells@redhat.com> cc: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
2011-08-19tracing/filter: Add startup tests for events filterJiri Olsa
Adding automated tests running as late_initcall. Tests are compiled in with CONFIG_FTRACE_STARTUP_TEST option. Adding test event "ftrace_test_filter" used to simulate filter processing during event occurance. String filters are compiled and tested against several test events with different values. Also testing that evaluation of explicit predicates is ommited due to the lazy filter evaluation. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1313072754-4620-11-git-send-email-jolsa@redhat.com Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-08-19tracing/filter: Change filter_match_preds function to use walk_pred_treeJiri Olsa
Changing filter_match_preds function to use unified predicates tree processing. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1313072754-4620-10-git-send-email-jolsa@redhat.com Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-08-19tracing/filter: Change fold_pred function to use walk_pred_treeJiri Olsa
Changing fold_pred_tree function to use unified predicates tree processing. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1313072754-4620-9-git-send-email-jolsa@redhat.com Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-08-19tracing/filter: Change fold_pred_tree function to use walk_pred_treeJiri Olsa
Changing fold_pred_tree function to use unified predicates tree processing. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1313072754-4620-8-git-send-email-jolsa@redhat.com Signed-off-by: Steven Rostedt <rostedt@goodmis.org>