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author | Wanpeng Li <wanpeng.li@hotmail.com> | 2017-07-09 09:40:28 +0200 |
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committer | Ingo Molnar <mingo@kernel.org> | 2017-07-14 10:27:15 +0200 |
commit | 0e4097c3354e2f5a5ad8affd9dc7f7f7d00bb6b9 (patch) | |
tree | 7806ceddfe0be9927e01527f5db610310bdbd71a /kernel/sched/deadline.c | |
parent | sched/headers/uapi: Fix linux/sched/types.h userspace compilation errors (diff) | |
download | linux-0e4097c3354e2f5a5ad8affd9dc7f7f7d00bb6b9.tar.xz linux-0e4097c3354e2f5a5ad8affd9dc7f7f7d00bb6b9.zip |
sched/cputime: Don't use smp_processor_id() in preemptible context
Recent kernels trigger this warning:
BUG: using smp_processor_id() in preemptible [00000000] code: 99-trinity/181
caller is debug_smp_processor_id+0x17/0x19
CPU: 0 PID: 181 Comm: 99-trinity Not tainted 4.12.0-01059-g2a42eb9 #1
Call Trace:
dump_stack+0x82/0xb8
check_preemption_disabled()
debug_smp_processor_id()
vtime_delta()
task_cputime()
thread_group_cputime()
thread_group_cputime_adjusted()
wait_consider_task()
do_wait()
SYSC_wait4()
do_syscall_64()
entry_SYSCALL64_slow_path()
As Frederic pointed out:
| Although those sched_clock_cpu() things seem to only matter when the
| sched_clock() is unstable. And that stability is a condition for nohz_full
| to work anyway. So probably sched_clock() alone would be enough.
This patch fixes it by replacing sched_clock_cpu() with sched_clock() to
avoid calling smp_processor_id() in a preemptible context.
Reported-by: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1499586028-7402-1-git-send-email-wanpeng.li@hotmail.com
[ Prettified the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/deadline.c')
0 files changed, 0 insertions, 0 deletions