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* time: Delete do_sys_setimeofday()Deepa Dinamani2017-04-143-4/+10
| | | | | | | | | | | | | | | | | | struct timespec is not y2038 safe on 32 bit machines and needs to be replaced with struct timespec64. do_sys_timeofday() is just a wrapper function. Replace all calls to this function with direct calls to do_sys_timeofday64() instead and delete do_sys_timeofday(). Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Cc: y2038@lists.linaro.org Cc: john.stultz@linaro.org Cc: arnd@arndb.de Cc: linux-alpha@vger.kernel.org Link: http://lkml.kernel.org/r/1490555058-4603-2-git-send-email-deepa.kernel@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* timekeeping: Remove pointless conversion to boolNicholas Mc Guire2017-03-311-2/+1
| | | | | | | | | | | | interp_forward is type bool so assignment from a logical operation directly is sufficient. Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at> Cc: "Christopher S. Hall" <christopher.s.hall@intel.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/1490382215-30505-1-git-send-email-der.herr@hofr.at Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Merge branch 'fortglx/4.12/time' of ↵Thomas Gleixner2017-03-313-1/+12
|\ | | | | | | | | | | | | | | | | | | | | https://git.linaro.org/people/john.stultz/linux into timers/core Pull timekeeping changes from John Stultz: Main changes are the initial steps of Nicoli's work to make the clockevent timers be corrected for NTP adjustments. Then a few smaller fixes that I've queued, and adding Stephen Boyd to the maintainers list for timekeeping.
| * sysrq: Reset the watchdog timers while displaying high-resolution timersTom Hromatka2017-03-231-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On systems with a large number of CPUs, running sysrq-<q> can cause watchdog timeouts. There are two slow sections of code in the sysrq-<q> path in timer_list.c. 1. print_active_timers() - This function is called by print_cpu() and contains a slow goto loop. On a machine with hundreds of CPUs, this loop took approximately 100ms for the first CPU in a NUMA node. (Subsequent CPUs in the same node ran much quicker.) The total time to print all of the CPUs is ultimately long enough to trigger the soft lockup watchdog. 2. print_tickdevice() - This function outputs a large amount of textual information. This function also took approximately 100ms per CPU. Since sysrq-<q> is not a performance critical path, there should be no harm in touching the nmi watchdog in both slow sections above. Touching it in just one location was insufficient on systems with hundreds of CPUs as occasional timeouts were still observed during testing. This issue was observed on an Oracle T7 machine with 128 CPUs, but I anticipate it may affect other systems with similarly large numbers of CPUs. Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com> Reviewed-by: Rob Gardner <rob.gardner@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
| * timers, sched_clock: Update timeout for clock wrapDavid Engraf2017-03-231-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The scheduler clock framework may not use the correct timeout for the clock wrap. This happens when a new clock driver calls sched_clock_register() after the kernel called sched_clock_postinit(). In this case the clock wrap timeout is too long thus sched_clock_poll() is called too late and the clock already wrapped. On my ARM system the scheduler was no longer scheduling any other task than the idle task because the sched_clock() wrapped. Signed-off-by: David Engraf <david.engraf@sysgo.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
| * clockevents: Make clockevents_config() staticNicolai Stange2017-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A clockevent device's rate should be configured before or at registration and changed afterwards through clockevents_update_freq() only. For the configuration at registration, we already have clockevents_config_and_register(). Right now, there are no clockevents_config() users outside of the clockevents core. To mitigiate the risk of drivers errorneously reconfiguring their rates through clockevents_config() *after* device registration, make clockevents_config() static. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | hrtimer: Remove hrtimer_peek_ahead_timers() leftoversStephen Boyd2017-03-171-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | This function was removed in commit c6eb3f70d448 (hrtimer: Get rid of hrtimer softirq, 2015-04-14) but the prototype wasn't ever deleted. Delete it now. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Link: http://lkml.kernel.org/r/20170317010814.2591-1-sboyd@codeaurora.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | rlimits: Print more information when CPU/RT limits are exceededArun Raghavan2017-03-131-2/+7
|/ | | | | | | | | | | | | | | | | When a process is sent a SIGKILL because it exceeded CPU or RT limits, the cause may not be obvious in userspace -- daemonised processes just get killed, and even foreground process just see a 'Killed' message. The lack of any information on why this might be happening in logs can be confusing to users who are not aware of this mechanism. Add messages which dump the process name and tid in dmesg when a process exceeds its CPU or RT limits (soft and hard) in order to make it clearer to people debugging such issues. Signed-off-by: Arun Raghavan <arun@arunraghavan.net> Link: http://lkml.kernel.org/r/20170301145309.27214-1-arun@arunraghavan.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-03-071-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "This includes a fix for lockups caused by incorrect nsecs related cleanup, and a capabilities check fix for timerfd" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: jiffies: Revert bogus conversion of NSEC_PER_SEC to TICK_NSEC timerfd: Only check CAP_WAKE_ALARM when it is needed
| * jiffies: Revert bogus conversion of NSEC_PER_SEC to TICK_NSECFrederic Weisbecker2017-03-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 93825f2ec736 converted NSEC_PER_SEC to TICK_NSEC because the author confused NSEC_PER_JIFFY with NSEC_PER_SEC. As a result, the calculation of refined jiffies got broken, triggering lockups. Fixes: 93825f2ec736 ("jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY") Reported-and-tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1488880534-3777-1-git-send-email-fweisbec@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | sched/headers: Prepare to move exit_files() and exit_itimers() from ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched.h> to <linux/sched/task.h> But first update the usage site. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare to move cputime functionality from <linux/sched.h> ↵Ingo Molnar2017-03-022-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | into <linux/sched/cputime.h> Introduce a trivial, mostly empty <linux/sched/cputime.h> header to prepare for the moving of cputime functionality out of sched.h. Update all code that relies on these facilities. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-023-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/debug.h> We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-023-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/nohz.h> We are going to split <linux/sched/nohz.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/nohz.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/stat.h> We are going to split <linux/sched/stat.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/stat.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar2017-03-023-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-022-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/nmi.h> We are going to move softlockup APIs out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. <linux/nmi.h> already includes <linux/sched.h>. Include the <linux/nmi.h> header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-023-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/signal.h> We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/signal.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/loadavg.h> We are going to split <linux/sched/loadavg.h> out of <linux/sched.h>, which will have to be picked up from a couple of .c files. Create a trivial placeholder <linux/sched/topology.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-022-0/+2
|/ | | | | | | | | | | | | | | | | | | | <linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2017-02-206-167/+115
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this (fairly busy) cycle were: - There was a class of scheduler bugs related to forgetting to update the rq-clock timestamp which can cause weird and hard to debug problems, so there's a new debug facility for this: which uncovered a whole lot of bugs which convinced us that we want to keep the debug facility. (Peter Zijlstra, Matt Fleming) - Various cputime related updates: eliminate cputime and use u64 nanoseconds directly, simplify and improve the arch interfaces, implement delayed accounting more widely, etc. - (Frederic Weisbecker) - Move code around for better structure plus cleanups (Ingo Molnar) - Move IO schedule accounting deeper into the scheduler plus related changes to improve the situation (Tejun Heo) - ... plus a round of sched/rt and sched/deadline fixes, plus other fixes, updats and cleanups" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (85 commits) sched/core: Remove unlikely() annotation from sched_move_task() sched/autogroup: Rename auto_group.[ch] to autogroup.[ch] sched/topology: Split out scheduler topology code from core.c into topology.c sched/core: Remove unnecessary #include headers sched/rq_clock: Consolidate the ordering of the rq_clock methods delayacct: Include <uapi/linux/taskstats.h> sched/core: Clean up comments sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds sched/clock: Add dummy clear_sched_clock_stable() stub function sched/cputime: Remove generic asm headers sched/cputime: Remove unused nsec_to_cputime() s390, sched/cputime: Remove unused cputime definitions powerpc, sched/cputime: Remove unused cputime definitions s390, sched/cputime: Make arch_cpu_idle_time() to return nsecs ia64, sched/cputime: Remove unused cputime definitions ia64: Convert vtime to use nsec units directly ia64, sched/cputime: Move the nsecs based cputime headers to the last arch using it sched/cputime: Remove jiffies based cputime sched/cputime, vtime: Return nsecs instead of cputime_t to account sched/cputime: Complete nsec conversion of tick based accounting ...
| * timers/itimer: Convert internal cputime_t units to nsecFrederic Weisbecker2017-02-012-68/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the new nsec based cputime accessors as part of the whole cputime conversion from cputime_t to nsecs. Also convert itimers to use nsec based internal counters. This simplifies it and removes the whole game with error/inc_error which served to deal with cputime_t random granularity. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1485832191-26889-20-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * timers/posix-timers: Convert internals to use nsecsFrederic Weisbecker2017-02-012-126/+90
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the new nsec based cputime accessors as part of the whole cputime conversion from cputime_t to nsecs. Also convert posix-cpu-timers to use nsec based internal counters to simplify it. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1485832191-26889-19-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * timers/posix-timers: Use TICK_NSEC instead of a dynamically ad-hoc ↵Frederic Weisbecker2017-02-011-9/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | calculated version Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1485832191-26889-18-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * sched/cputime: Introduce special task_cputime_t() API to return old-typed ↵Frederic Weisbecker2017-02-012-24/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cputime This API returns a task's cputime in cputime_t in order to ease the conversion of cputime internals to use nsecs units instead. Blindly converting all cputime readers to use this API now will later let us convert more smoothly and step by step all these places to use the new nsec based cputime. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1485832191-26889-7-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * time: Introduce jiffies64_to_nsecs()Frederic Weisbecker2017-02-012-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This will be needed for the cputime_t to nsec conversion. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1485832191-26889-2-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFYFrederic Weisbecker2017-02-011-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NSEC_PER_JIFFY is an ad-hoc redefinition of TICK_NSEC. Let's rather use a unique and well maintained version. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Link: http://lkml.kernel.org/r/1485832191-26889-1-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * Merge branch 'linus' into sched/core, to pick up fixes and refresh the branchIngo Molnar2017-02-012-2/+9
| |\ | | | | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | sched/clock, clocksource: Add optional cs::mark_unstable() methodThomas Gleixner2017-01-141-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PeterZ reported that we'd fail to mark the TSC unstable when the clocksource watchdog finds it unsuitable. Allow a clocksource to run a custom action when its being marked unstable and hook up the TSC unstable code. Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2017-02-208-573/+27
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Nothing exciting, just the usual pile of fixes, updates and cleanups: - A bunch of clocksource driver updates - Removal of CONFIG_TIMER_STATS and the related /proc file - More posix timer slim down work - A scalability enhancement in the tick broadcast code - Math cleanups" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) hrtimer: Catch invalid clockids again math64, tile: Fix build failure clocksource/drivers/arm_arch_timer:: Mark cyclecounter __ro_after_init timerfd: Protect the might cancel mechanism proper timer_list: Remove useless cast when printing time: Remove CONFIG_TIMER_STATS clocksource/drivers/arm_arch_timer: Work around Hisilicon erratum 161010101 clocksource/drivers/arm_arch_timer: Introduce generic errata handling infrastructure clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameter clocksource/drivers/arm_arch_timer: Add dt binding for hisilicon-161010101 erratum clocksource/drivers/ostm: Add renesas-ostm timer driver clocksource/drivers/ostm: Document renesas-ostm timer DT bindings clocksource/drivers/tcb_clksrc: Use 32 bit tcb as sched_clock clocksource/drivers/gemini: Add driver for the Cortina Gemini clocksource: add DT bindings for Cortina Gemini clockevents: Add a clkevt-of mechanism like clksrc-of tick/broadcast: Reduce lock cacheline contention timers: Omit POSIX timer stuff from task_struct when disabled x86/timer: Make delay() work during early bootup delay: Add explanation of udelay() inaccuracy ...
| * | | hrtimer: Catch invalid clockids againMarc Zyngier2017-02-181-5/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 82e88ff1ea94 ("hrtimer: Revert CLOCK_MONOTONIC_RAW support") removed unfortunately a sanity check in the hrtimer code which was part of that MONOTONIC_RAW patch series. It would have caught the bogus usage of CLOCK_MONOTONIC_RAW in the wireless code. So bring it back. It is way too easy to take any random clockid and feed it to the hrtimer subsystem. At best, it gets mapped to a monotonic base, but it would be better to just catch illegal values as early as possible. Detect invalid clockids, map them to CLOCK_MONOTONIC and emit a warning. [ tglx: Replaced the BUG by a WARN and gracefully map to CLOCK_MONOTONIC ] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Link: http://lkml.kernel.org/r/1452879670-16133-3-git-send-email-marc.zyngier@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | timer_list: Remove useless cast when printingMars Cheng2017-02-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hrtimer_resolution is already unsigned int, not necessary to cast it when printing. Signed-off-by: Mars Cheng <mars.cheng@mediatek.com> Cc: CC Hwang <cc.hwang@mediatek.com> Cc: wsd_upstream@mediatek.com Cc: Loda Chou <loda.chou@mediatek.com> Cc: Jades Shih <jades.shih@mediatek.com> Cc: Miles Chen <miles.chen@mediatek.com> Cc: John Stultz <john.stultz@linaro.org> Cc: My Chuang <my.chuang@mediatek.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Yingjoe Chen <yingjoe.chen@mediatek.com> Link: http://lkml.kernel.org/r/1486626615-5879-1-git-send-email-mars.cheng@mediatek.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | time: Remove CONFIG_TIMER_STATSKees Cook2017-02-105-520/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently CONFIG_TIMER_STATS exposes process information across namespaces: kernel/time/timer_list.c print_timer(): SEQ_printf(m, ", %s/%d", tmp, timer->start_pid); /proc/timer_list: #11: <0000000000000000>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570 Given that the tracer can give the same information, this patch entirely removes CONFIG_TIMER_STATS. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: John Stultz <john.stultz@linaro.org> Cc: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: linux-doc@vger.kernel.org Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Xing Gao <xgao01@email.wm.edu> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jessica Frazelle <me@jessfraz.com> Cc: kernel-hardening@lists.openwall.com Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Michal Marek <mmarek@suse.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Olof Johansson <olof@lixom.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-api@vger.kernel.org Cc: Arjan van de Ven <arjan@linux.intel.com> Link: http://lkml.kernel.org/r/20170208192659.GA32582@beast Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | tick/broadcast: Reduce lock cacheline contentionWaiman Long2017-02-041-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was observed that on an Intel x86 system without the ARAT (Always running APIC timer) feature and with fairly large number of CPUs as well as CPUs coming in and out of intel_idle frequently, the lock contention on the tick_broadcast_lock can become significant. To reduce contention, the lock is put into its own cacheline and all the cpumask_var_t variables are put into the __read_mostly section. Running the SP benchmark of the NAS Parallel Benchmarks on a 4-socket 16-core 32-thread Nehalam system, the performance number improved from 3353.94 Mop/s to 3469.31 Mop/s when this patch was applied on a 4.9.6 kernel. This is a 3.4% improvement. Signed-off-by: Waiman Long <longman@redhat.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/1485799063-20857-1-git-send-email-longman@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | timekeeping: Remove unused timekeeping_{get,set}_tai_offset()Stephen Boyd2017-01-062-40/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The last caller to timekeeping_set_tai_offset() was in commit 0b5154fb9040 (timekeeping: Simplify tai updating from do_adjtimex, 2013-03-22) and the last caller to timekeeping_get_tai_offset() was in commit 76f4108892d9 (hrtimer: Cleanup hrtimer accessors to the timekepeing state, 2014-07-16). Remove these unused functions now that we handle TAI offsets differently. Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-02-182-10/+9
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Two small fixes:: - Prevent deadlock on the tick broadcast lock. Found and fixed by Mike. - Stop using printk() in the timekeeping debug code to prevent a deadlock against the scheduler" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Use deferred printk() in debug code tick/broadcast: Prevent deadlock on tick_broadcast_lock
| * | | timekeeping: Use deferred printk() in debug codeSergey Senozhatsky2017-02-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We cannot do printk() from tk_debug_account_sleep_time(), because tk_debug_account_sleep_time() is called under tk_core seq lock. The reason why printk() is unsafe there is that console_sem may invoke scheduler (up()->wake_up_process()->activate_task()), which, in turn, can return back to timekeeping code, for instance, via get_time()->ktime_get(), deadlocking the system on tk_core seq lock. [ 48.950592] ====================================================== [ 48.950622] [ INFO: possible circular locking dependency detected ] [ 48.950622] 4.10.0-rc7-next-20170213+ #101 Not tainted [ 48.950622] ------------------------------------------------------- [ 48.950622] kworker/0:0/3 is trying to acquire lock: [ 48.950653] (tk_core){----..}, at: [<c01cc624>] retrigger_next_event+0x4c/0x90 [ 48.950683] but task is already holding lock: [ 48.950683] (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90 [ 48.950714] which lock already depends on the new lock. [ 48.950714] the existing dependency chain (in reverse order) is: [ 48.950714] -> #5 (hrtimer_bases.lock){-.-...}: [ 48.950744] _raw_spin_lock_irqsave+0x50/0x64 [ 48.950775] lock_hrtimer_base+0x28/0x58 [ 48.950775] hrtimer_start_range_ns+0x20/0x5c8 [ 48.950775] __enqueue_rt_entity+0x320/0x360 [ 48.950805] enqueue_rt_entity+0x2c/0x44 [ 48.950805] enqueue_task_rt+0x24/0x94 [ 48.950836] ttwu_do_activate+0x54/0xc0 [ 48.950836] try_to_wake_up+0x248/0x5c8 [ 48.950836] __setup_irq+0x420/0x5f0 [ 48.950836] request_threaded_irq+0xdc/0x184 [ 48.950866] devm_request_threaded_irq+0x58/0xa4 [ 48.950866] omap_i2c_probe+0x530/0x6a0 [ 48.950897] platform_drv_probe+0x50/0xb0 [ 48.950897] driver_probe_device+0x1f8/0x2cc [ 48.950897] __driver_attach+0xc0/0xc4 [ 48.950927] bus_for_each_dev+0x6c/0xa0 [ 48.950927] bus_add_driver+0x100/0x210 [ 48.950927] driver_register+0x78/0xf4 [ 48.950958] do_one_initcall+0x3c/0x16c [ 48.950958] kernel_init_freeable+0x20c/0x2d8 [ 48.950958] kernel_init+0x8/0x110 [ 48.950988] ret_from_fork+0x14/0x24 [ 48.950988] -> #4 (&rt_b->rt_runtime_lock){-.-...}: [ 48.951019] _raw_spin_lock+0x40/0x50 [ 48.951019] rq_offline_rt+0x9c/0x2bc [ 48.951019] set_rq_offline.part.2+0x2c/0x58 [ 48.951049] rq_attach_root+0x134/0x144 [ 48.951049] cpu_attach_domain+0x18c/0x6f4 [ 48.951049] build_sched_domains+0xba4/0xd80 [ 48.951080] sched_init_smp+0x68/0x10c [ 48.951080] kernel_init_freeable+0x160/0x2d8 [ 48.951080] kernel_init+0x8/0x110 [ 48.951080] ret_from_fork+0x14/0x24 [ 48.951110] -> #3 (&rq->lock){-.-.-.}: [ 48.951110] _raw_spin_lock+0x40/0x50 [ 48.951141] task_fork_fair+0x30/0x124 [ 48.951141] sched_fork+0x194/0x2e0 [ 48.951141] copy_process.part.5+0x448/0x1a20 [ 48.951171] _do_fork+0x98/0x7e8 [ 48.951171] kernel_thread+0x2c/0x34 [ 48.951171] rest_init+0x1c/0x18c [ 48.951202] start_kernel+0x35c/0x3d4 [ 48.951202] 0x8000807c [ 48.951202] -> #2 (&p->pi_lock){-.-.-.}: [ 48.951232] _raw_spin_lock_irqsave+0x50/0x64 [ 48.951232] try_to_wake_up+0x30/0x5c8 [ 48.951232] up+0x4c/0x60 [ 48.951263] __up_console_sem+0x2c/0x58 [ 48.951263] console_unlock+0x3b4/0x650 [ 48.951263] vprintk_emit+0x270/0x474 [ 48.951293] vprintk_default+0x20/0x28 [ 48.951293] printk+0x20/0x30 [ 48.951324] kauditd_hold_skb+0x94/0xb8 [ 48.951324] kauditd_thread+0x1a4/0x56c [ 48.951324] kthread+0x104/0x148 [ 48.951354] ret_from_fork+0x14/0x24 [ 48.951354] -> #1 ((console_sem).lock){-.....}: [ 48.951385] _raw_spin_lock_irqsave+0x50/0x64 [ 48.951385] down_trylock+0xc/0x2c [ 48.951385] __down_trylock_console_sem+0x24/0x80 [ 48.951385] console_trylock+0x10/0x8c [ 48.951416] vprintk_emit+0x264/0x474 [ 48.951416] vprintk_default+0x20/0x28 [ 48.951416] printk+0x20/0x30 [ 48.951446] tk_debug_account_sleep_time+0x5c/0x70 [ 48.951446] __timekeeping_inject_sleeptime.constprop.3+0x170/0x1a0 [ 48.951446] timekeeping_resume+0x218/0x23c [ 48.951477] syscore_resume+0x94/0x42c [ 48.951477] suspend_enter+0x554/0x9b4 [ 48.951477] suspend_devices_and_enter+0xd8/0x4b4 [ 48.951507] enter_state+0x934/0xbd4 [ 48.951507] pm_suspend+0x14/0x70 [ 48.951507] state_store+0x68/0xc8 [ 48.951538] kernfs_fop_write+0xf4/0x1f8 [ 48.951538] __vfs_write+0x1c/0x114 [ 48.951538] vfs_write+0xa0/0x168 [ 48.951568] SyS_write+0x3c/0x90 [ 48.951568] __sys_trace_return+0x0/0x10 [ 48.951568] -> #0 (tk_core){----..}: [ 48.951599] lock_acquire+0xe0/0x294 [ 48.951599] ktime_get_update_offsets_now+0x5c/0x1d4 [ 48.951629] retrigger_next_event+0x4c/0x90 [ 48.951629] on_each_cpu+0x40/0x7c [ 48.951629] clock_was_set_work+0x14/0x20 [ 48.951660] process_one_work+0x2b4/0x808 [ 48.951660] worker_thread+0x3c/0x550 [ 48.951660] kthread+0x104/0x148 [ 48.951690] ret_from_fork+0x14/0x24 [ 48.951690] other info that might help us debug this: [ 48.951690] Chain exists of: tk_core --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock [ 48.951721] Possible unsafe locking scenario: [ 48.951721] CPU0 CPU1 [ 48.951721] ---- ---- [ 48.951721] lock(hrtimer_bases.lock); [ 48.951751] lock(&rt_b->rt_runtime_lock); [ 48.951751] lock(hrtimer_bases.lock); [ 48.951751] lock(tk_core); [ 48.951782] *** DEADLOCK *** [ 48.951782] 3 locks held by kworker/0:0/3: [ 48.951782] #0: ("events"){.+.+.+}, at: [<c0156590>] process_one_work+0x1f8/0x808 [ 48.951812] #1: (hrtimer_work){+.+...}, at: [<c0156590>] process_one_work+0x1f8/0x808 [ 48.951843] #2: (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90 [ 48.951843] stack backtrace: [ 48.951873] CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.10.0-rc7-next-20170213+ [ 48.951904] Workqueue: events clock_was_set_work [ 48.951904] [<c0110208>] (unwind_backtrace) from [<c010c224>] (show_stack+0x10/0x14) [ 48.951934] [<c010c224>] (show_stack) from [<c04ca6c0>] (dump_stack+0xac/0xe0) [ 48.951934] [<c04ca6c0>] (dump_stack) from [<c019b5cc>] (print_circular_bug+0x1d0/0x308) [ 48.951965] [<c019b5cc>] (print_circular_bug) from [<c019d2a8>] (validate_chain+0xf50/0x1324) [ 48.951965] [<c019d2a8>] (validate_chain) from [<c019ec18>] (__lock_acquire+0x468/0x7e8) [ 48.951995] [<c019ec18>] (__lock_acquire) from [<c019f634>] (lock_acquire+0xe0/0x294) [ 48.951995] [<c019f634>] (lock_acquire) from [<c01d0ea0>] (ktime_get_update_offsets_now+0x5c/0x1d4) [ 48.952026] [<c01d0ea0>] (ktime_get_update_offsets_now) from [<c01cc624>] (retrigger_next_event+0x4c/0x90) [ 48.952026] [<c01cc624>] (retrigger_next_event) from [<c01e4e24>] (on_each_cpu+0x40/0x7c) [ 48.952056] [<c01e4e24>] (on_each_cpu) from [<c01cafc4>] (clock_was_set_work+0x14/0x20) [ 48.952056] [<c01cafc4>] (clock_was_set_work) from [<c015664c>] (process_one_work+0x2b4/0x808) [ 48.952087] [<c015664c>] (process_one_work) from [<c0157774>] (worker_thread+0x3c/0x550) [ 48.952087] [<c0157774>] (worker_thread) from [<c015d644>] (kthread+0x104/0x148) [ 48.952087] [<c015d644>] (kthread) from [<c0107830>] (ret_from_fork+0x14/0x24) Replace printk() with printk_deferred(), which does not call into the scheduler. Fixes: 0bf43f15db85 ("timekeeping: Prints the amounts of time spent during suspend") Reported-and-tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J . Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: John Stultz <john.stultz@linaro.org> Cc: "[4.9+]" <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20170215044332.30449-1-sergey.senozhatsky@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | tick/broadcast: Prevent deadlock on tick_broadcast_lockMike Galbraith2017-02-131-8/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tick_broadcast_lock is taken from interrupt context, but the following call chain takes the lock without disabling interrupts: [ 12.703736] _raw_spin_lock+0x3b/0x50 [ 12.703738] tick_broadcast_control+0x5a/0x1a0 [ 12.703742] intel_idle_cpu_online+0x22/0x100 [ 12.703744] cpuhp_invoke_callback+0x245/0x9d0 [ 12.703752] cpuhp_thread_fun+0x52/0x110 [ 12.703754] smpboot_thread_fn+0x276/0x320 So the following deadlock can happen: lock(tick_broadcast_lock); <Interrupt> lock(tick_broadcast_lock); intel_idle_cpu_online() is the only place which violates the calling convention of tick_broadcast_control(). This was caused by the removal of the smp function call in course of the cpu hotplug rework. Instead of slapping local_irq_disable/enable() at the call site, we can relax the calling convention and handle it in the core code, which makes the whole machinery more robust. Fixes: 29d7bbada98e ("intel_idle: Remove superfluous SMP fuction call") Reported-by: Gabriel C <nix.or.die@gmail.com> Signed-off-by: Mike Galbraith <efault@gmx.de> Cc: Ruslan Ruslichenko <rruslich@cisco.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: lwn@lwn.net Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: stable <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1486953115.5912.4.camel@gmx.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | Revert "nohz: Fix collision between tick and other hrtimers"Linus Torvalds2017-02-162-14/+2
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 24b91e360ef521a2808771633d76ebc68bd5604b and commit 7bdb59f1ad47 ("tick/nohz: Fix possible missing clock reprog after tick soft restart") that depends on it, Pavel reports that it causes occasional boot hangs for him that seem to depend on just how the machine was booted. In particular, his machine hangs at around the PCI fixups of the EHCI USB host controller, but only hangs from cold boot, not from a warm boot. Thomas Gleixner suspecs it's a CPU hotplug interaction, particularly since Pavel also saw suspend/resume issues that seem to be related. We're reverting for now while trying to figure out the root cause. Reported-bisected-and-tested-by: Pavel Machek <pavel@ucw.cz> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org # reverted commits were marked for stable Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | tick/nohz: Fix possible missing clock reprog after tick soft restartFrederic Weisbecker2017-02-101-0/+5
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ts->next_tick keeps track of the next tick deadline in order to optimize clock programmation on irq exit and avoid redundant clock device writes. Now if ts->next_tick missed an update, we may spuriously miss a clock reprog later as the nohz code is fooled by an obsolete next_tick value. This is what happens here on a specific path: when we observe an expired timer from the nohz update code on irq exit, we perform a soft tick restart which simply fires the closest possible tick without actually exiting the nohz mode and restoring a periodic state. But we forget to update ts->next_tick accordingly. As a result, after the next tick resulting from such soft tick restart, the nohz code sees a stale value on ts->next_tick which doesn't match the clock deadline that just expired. If that obsolete ts->next_tick value happens to collide with the actual next tick deadline to be scheduled, we may spuriously bypass the clock reprogramming. In the worst case, the tick may never fire again. Fix this with a ts->next_tick reset on soft tick restart. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed: Wanpeng Li <wanpeng.li@hotmail.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1486485894-29173-1-git-send-email-fweisbec@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | nohz: Fix collision between tick and other hrtimersFrederic Weisbecker2017-01-112-2/+9
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the tick is stopped and an interrupt occurs afterward, we check on that interrupt exit if the next tick needs to be rescheduled. If it doesn't need any update, we don't want to do anything. In order to check if the tick needs an update, we compare it against the clockevent device deadline. Now that's a problem because the clockevent device is at a lower level than the tick itself if it is implemented on top of hrtimer. Every hrtimer share this clockevent device. So comparing the next tick deadline against the clockevent device deadline is wrong because the device may be programmed for another hrtimer whose deadline collides with the tick. As a result we may end up not reprogramming the tick accidentally. In a worst case scenario under full dynticks mode, the tick stops firing as it is supposed to every 1hz, leaving /proc/stat stalled: Task in a full dynticks CPU ---------------------------- * hrtimer A is queued 2 seconds ahead * the tick is stopped, scheduled 1 second ahead * tick fires 1 second later * on tick exit, nohz schedules the tick 1 second ahead but sees the clockevent device is already programmed to that deadline, fooled by hrtimer A, the tick isn't rescheduled. * hrtimer A is cancelled before its deadline * tick never fires again until an interrupt happens... In order to fix this, store the next tick deadline to the tick_sched local structure and reuse that value later to check whether we need to reprogram the clock after an interrupt. On the other hand, ts->sleep_length still wants to know about the next clock event and not just the tick, so we want to improve the related comment to avoid confusion. Reported-by: James Hartsock <hartsjc@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Rik van Riel <riel@redhat.com> Link: http://lkml.kernel.org/r/1483539124-5693-1-git-send-email-fweisbec@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* ktime: Cleanup ktime_set() usageThomas Gleixner2016-12-254-6/+6
| | | | | | | | | | ktime_set(S,N) was required for the timespec storage type and is still useful for situations where a Seconds and Nanoseconds part of a time value needs to be converted. For anything where the Seconds argument is 0, this is pointless and can be replaced with a simple assignment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
* ktime: Get rid of the unionThomas Gleixner2016-12-2511-83/+83
| | | | | | | | | | | | | | | ktime is a union because the initial implementation stored the time in scalar nanoseconds on 64 bit machine and in a endianess optimized timespec variant for 32bit machines. The Y2038 cleanup removed the timespec variant and switched everything to scalar nanoseconds. The union remained, but become completely pointless. Get rid of the union and just keep ktime_t as simple typedef of type s64. The conversion was done with coccinelle and some manual mopping up. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
* clocksource: Use a plain u64 instead of cycle_tThomas Gleixner2016-12-255-39/+36
| | | | | | | | | | | | | | | | | | | | | There is no point in having an extra type for extra confusion. u64 is unambiguous. Conversion was done with the following coccinelle script: @rem@ @@ -typedef u64 cycle_t; @fix@ typedef cycle_t; @@ -cycle_t +u64 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org>
* Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds2016-12-248-8/+8
| | | | | | | | | | | | | This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2016-12-181-0/+3
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "Prevent NULL pointer dereferencing in the tick broadcast code. Old bug, which got unearthed by the hotplug ordering problem" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick/broadcast: Prevent NULL pointer dereference
| * tick/broadcast: Prevent NULL pointer dereferenceThomas Gleixner2016-12-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a disfunctional timer, e.g. dummy timer, is installed, the tick core tries to setup the broadcast timer. If no broadcast device is installed, the kernel crashes with a NULL pointer dereference in tick_broadcast_setup_oneshot() because the function has no sanity check. Reported-by: Mason <slash.tmp@free.fr> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Richard Cochran <rcochran@linutronix.de> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org>, Cc: Sebastian Frias <sf84@laposte.net> Cc: Thibaud Cornic <thibaud_cornic@sigmadesigns.com> Cc: Robin Murphy <robin.murphy@arm.com> Link: http://lkml.kernel.org/r/1147ef90-7877-e4d2-bb2b-5c4fa8d3144b@free.fr
* | posix-timers: give lazy compilers some help optimizing code awayNicolas Pitre2016-12-141-1/+2
|/ | | | | | | | | | | | | | | | | | The OpenRISC compiler (so far) fails to optimize away a large portion of code containing a reference to posix_timer_event in alarmtimer.c when CONFIG_POSIX_TIMERS is unset. Let's give it a direct clue to let the build succeed. This fixes [linux-next:master 6682/7183] alarmtimer.c:undefined reference to `posix_timer_event' reported by kbuild test robot. Signed-off-by: Nicolas Pitre <nico@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2016-12-128-94/+275
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "The time/timekeeping/timer folks deliver with this update: - Fix a reintroduced signed/unsigned issue and cleanup the whole signed/unsigned mess in the timekeeping core so this wont happen accidentaly again. - Add a new trace clock based on boot time - Prevent injection of random sleep times when PM tracing abuses the RTC for storage - Make posix timers configurable for real tiny systems - Add tracepoints for the alarm timer subsystem so timer based suspend wakeups can be instrumented - The usual pile of fixes and updates to core and drivers" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) timekeeping: Use mul_u64_u32_shr() instead of open coding it timekeeping: Get rid of pointless typecasts timekeeping: Make the conversion call chain consistently unsigned timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion alarmtimer: Add tracepoints for alarm timers trace: Update documentation for mono, mono_raw and boot clock trace: Add an option for boot clock as trace clock timekeeping: Add a fast and NMI safe boot clock timekeeping/clocksource_cyc2ns: Document intended range limitation timekeeping: Ignore the bogus sleep time if pm_trace is enabled selftests/timers: Fix spelling mistake "Asyncrhonous" -> "Asynchronous" clocksource/drivers/bcm2835_timer: Unmap region obtained by of_iomap clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map() arm64: dts: rockchip: Arch counter doesn't tick in system suspend clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend posix-timers: Make them configurable posix_cpu_timers: Move the add_device_randomness() call to a proper place timer: Move sys_alarm from timer.c to itimer.c ptp_clock: Allow for it to be optional Kconfig: Regenerate *.c_shipped files after previous changes ...
| * timekeeping: Use mul_u64_u32_shr() instead of open coding itThomas Gleixner2016-12-091-21/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The resume code must deal with a clocksource delta which is potentially big enough to overflow the 64bit mult. Replace the open coded handling with the proper function. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Parit Bhargava <prarit@redhat.com> Cc: Laurent Vivier <lvivier@redhat.com> Cc: "Christopher S. Hall" <christopher.s.hall@intel.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Liav Rehana <liavr@mellanox.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20161208204228.921674404@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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