linux/kernel/sched
Juri Lelli ecda2b66e2 sched/deadline: Fix missing clock update
A missing clock update is causing the following warning:

 rq->clock_update_flags < RQCF_ACT_SKIP
 WARNING: CPU: 10 PID: 0 at kernel/sched/sched.h:963 inactive_task_timer+0x5d6/0x720
 Call Trace:
  <IRQ>
  __hrtimer_run_queues+0x10f/0x530
  hrtimer_interrupt+0xe5/0x240
  smp_apic_timer_interrupt+0x79/0x2b0
  apic_timer_interrupt+0xf/0x20
  </IRQ>
  do_idle+0x203/0x280
  cpu_startup_entry+0x6f/0x80
  start_secondary+0x1b0/0x200
  secondary_startup_64+0xa5/0xb0
 hardirqs last  enabled at (793919): [<ffffffffa27c5f6e>] cpuidle_enter_state+0x9e/0x360
 hardirqs last disabled at (793920): [<ffffffffa2a0096e>] interrupt_entry+0xce/0xe0
 softirqs last  enabled at (793922): [<ffffffffa20bef78>] irq_enter+0x68/0x70
 softirqs last disabled at (793921): [<ffffffffa20bef5d>] irq_enter+0x4d/0x70

This happens because inactive_task_timer() calls sub_running_bw() (if
TASK_DEAD and non_contending) that might trigger a schedutil update,
which might access the clock. Clock is however currently updated only
later in inactive_task_timer() function.

Fix the problem by updating the clock right after task_rq_lock().

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Claudio Scordino <claudio@evidence.eu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@santannapisa.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180530160809.9074-1-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-31 12:27:13 +02:00
..
autogroup.c sched/autogroup: Fix possible Spectre-v1 indexing for sched_prio_to_weight[] 2018-05-05 08:34:42 +02:00
autogroup.h sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
clock.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
completion.c sched/completions: Use bool in try_wait_for_completion() 2018-03-09 08:00:18 +01:00
core.c sched/core: Require cpu_active() in select_task_rq(), for user tasks 2018-05-31 12:24:25 +02:00
cpuacct.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpudeadline.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpudeadline.h sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpufreq_schedutil.c cpufreq: schedutil: Avoid using invalid next_freq 2018-05-09 12:21:17 +02:00
cpufreq.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpupri.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cpupri.h sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
cputime.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
deadline.c sched/deadline: Fix missing clock update 2018-05-31 12:27:13 +02:00
debug.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 11:49:41 -07:00
fair.c Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-13 10:53:08 -07:00
features.h sched/fair: Update util_est only on util_avg updates 2018-03-20 08:11:09 +01:00
idle.c sched: idle: Select idle state before stopping the tick 2018-04-09 11:54:07 +02:00
isolation.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
loadavg.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
Makefile sched/idle: Merge kernel/sched/idle.c and kernel/sched/idle_task.c 2018-03-04 12:39:33 +01:00
membarrier.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
rt.c sched/debug: Move the print_rt_rq() and print_dl_rq() declarations to kernel/sched/sched.h 2018-05-18 09:05:14 +02:00
sched-pelt.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sched.h sched/debug: Move the print_rt_rq() and print_dl_rq() declarations to kernel/sched/sched.h 2018-05-18 09:05:14 +02:00
stats.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
stats.h sched: Clean up and harmonize the coding style of the scheduler code base 2018-03-03 15:50:21 +01:00
stop_task.c sched: Clean up and harmonize the coding style of the scheduler code base 2018-03-03 15:50:21 +01:00
swait.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00
topology.c sched/topology: Clarify root domain(s) debug string 2018-05-25 08:03:38 +02:00
wait_bit.c sched/wait: Improve __var_waitqueue() code generation 2018-03-20 08:23:25 +01:00
wait.c sched/headers: Simplify and clean up header usage in the scheduler 2018-03-04 12:39:29 +01:00