On 04/11/22 15:22, Greg KH wrote: > On Sun, Apr 10, 2022 at 12:38:29AM +0100, Qais Yousef wrote: > > On 03/08/22 18:51, Qais Yousef wrote: > > > On 03/08/22 19:10, Greg KH wrote: > > > > On Tue, Mar 08, 2022 at 06:02:40PM +0000, Qais Yousef wrote: > > > > > +CC stable > > > > > > > > > > On 03/01/22 15:24, tip-bot2 for Valentin Schneider wrote: > > > > > > The following commit has been merged into the sched/core branch of tip: > > > > > > > > > > > > Commit-ID: fa2c3254d7cfff5f7a916ab928a562d1165f17bb > > > > > > Gitweb: https://git.kernel.org/tip/fa2c3254d7cfff5f7a916ab928a562d1165f17bb > > > > > > Author: Valentin Schneider <valentin.schneider@xxxxxxx> > > > > > > AuthorDate: Thu, 20 Jan 2022 16:25:19 > > > > > > Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > > > > > > CommitterDate: Tue, 01 Mar 2022 16:18:39 +01:00 > > > > > > > > > > > > sched/tracing: Don't re-read p->state when emitting sched_switch event > > > > > > > > > > > > As of commit > > > > > > > > > > > > c6e7bd7afaeb ("sched/core: Optimize ttwu() spinning on p->on_cpu") > > > > > > > > > > > > the following sequence becomes possible: > > > > > > > > > > > > p->__state = TASK_INTERRUPTIBLE; > > > > > > __schedule() > > > > > > deactivate_task(p); > > > > > > ttwu() > > > > > > READ !p->on_rq > > > > > > p->__state=TASK_WAKING > > > > > > trace_sched_switch() > > > > > > __trace_sched_switch_state() > > > > > > task_state_index() > > > > > > return 0; > > > > > > > > > > > > TASK_WAKING isn't in TASK_REPORT, so the task appears as TASK_RUNNING in > > > > > > the trace event. > > > > > > > > > > > > Prevent this by pushing the value read from __schedule() down the trace > > > > > > event. > > > > > > > > > > > > Reported-by: Abhijeet Dharmapurikar <adharmap@xxxxxxxxxxx> > > > > > > Signed-off-by: Valentin Schneider <valentin.schneider@xxxxxxx> > > > > > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > > > > > > Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> > > > > > > Link: https://lore.kernel.org/r/20220120162520.570782-2-valentin.schneider@xxxxxxx > > > > > > > > > > Any objection to picking this for stable? I'm interested in this one for some > > > > > Android users but prefer if it can be taken by stable rather than backport it > > > > > individually. > > > > > > > > > > I think it makes sense to pick the next one in the series too. > > > > > > > > What commit does this fix in Linus's tree? > > > > > > It should be this one: c6e7bd7afaeb ("sched/core: Optimize ttwu() spinning on p->on_cpu") > > > > Should this be okay to be picked up by stable now? I can see AUTOSEL has picked > > it up for v5.15+, but it impacts v5.10 too. > > It does not apply to 5.10 at all, how did you test this? > > {sigh} > > Again, if you want this applied to any stable trees, please test that it > works and send the properly backported patches. Sorry. I'm picking up pieces after a colleague left and was under the impression that 5.10 Android users already use as-is, but due to GKI just need it formally in stable. Few things got lost in translation, I am very sorry! Let me sort all of this out properly including the testing part for 5.15 too. Thanks! -- Qais Yousef
