diff options
| author | David Engraf <david.engraf@sysgo.com> | 2017-02-17 08:51:03 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-22 09:23:21 +0100 |
| commit | 6c07f47bbadcd54e5b54e539719528bfb146b4c6 (patch) | |
| tree | 4d5274ddd11a71e8c18af08449b2af4f0f494a23 /kernel | |
| parent | fb796cd622706be3b0481f7e0e5f8ed0e2b06d91 (diff) | |
timers, sched_clock: Update timeout for clock wrap
[ Upstream commit 1b8955bc5ac575009835e371ae55e7f3af2197a9 ]
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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/sched_clock.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c index a26036d37a38..382b159d8592 100644 --- a/kernel/time/sched_clock.c +++ b/kernel/time/sched_clock.c @@ -205,6 +205,11 @@ sched_clock_register(u64 (*read)(void), int bits, unsigned long rate) update_clock_read_data(&rd); + if (sched_clock_timer.function != NULL) { + /* update timeout for clock wrap */ + hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL); + } + r = rate; if (r >= 4000000) { r /= 1000000; |