diff options
| author | Davidlohr Bueso <dave@stgolabs.net> | 2018-04-02 09:49:54 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-30 07:49:08 +0200 |
| commit | 094c145f4cb0c278e755f56faca21a77800eb2fd (patch) | |
| tree | 81dc263bd87115eb9e7b56beb54ff0fae665109c /kernel | |
| parent | 6b6933fdb14c030dd082dde9ff3b1f0db87fc62f (diff) | |
sched/rt: Fix rq->clock_update_flags < RQCF_ACT_SKIP warning
[ Upstream commit d29a20645d5e929aa7e8616f28e5d8e1c49263ec ]
While running rt-tests' pi_stress program I got the following splat:
rq->clock_update_flags < RQCF_ACT_SKIP
WARNING: CPU: 27 PID: 0 at kernel/sched/sched.h:960 assert_clock_updated.isra.38.part.39+0x13/0x20
[...]
<IRQ>
enqueue_top_rt_rq+0xf4/0x150
? cpufreq_dbs_governor_start+0x170/0x170
sched_rt_rq_enqueue+0x65/0x80
sched_rt_period_timer+0x156/0x360
? sched_rt_rq_enqueue+0x80/0x80
__hrtimer_run_queues+0xfa/0x260
hrtimer_interrupt+0xcb/0x220
smp_apic_timer_interrupt+0x62/0x120
apic_timer_interrupt+0xf/0x20
</IRQ>
[...]
do_idle+0x183/0x1e0
cpu_startup_entry+0x5f/0x70
start_secondary+0x192/0x1d0
secondary_startup_64+0xa5/0xb0
We can get rid of it be the "traditional" means of adding an
update_rq_clock() call after acquiring the rq->lock in
do_sched_rt_period_timer().
The case for the RT task throttling (which this workload also hits)
can be ignored in that the skip_update call is actually bogus and
quite the contrary (the request bits are removed/reverted).
By setting RQCF_UPDATED we really don't care if the skip is happening
or not and will therefore make the assert_clock_updated() check happy.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Cc: linux-kernel@vger.kernel.org
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/20180402164954.16255-1-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.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/sched/rt.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 2ef31c93e195..801b4ec40702 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -822,6 +822,8 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun) struct rq *rq = rq_of_rt_rq(rt_rq); raw_spin_lock(&rq->lock); + update_rq_clock(rq); + if (rt_rq->rt_time) { u64 runtime; |