On 2022/7/25 23:39, Johannes Weiner wrote: > On Thu, Jul 21, 2022 at 12:04:31PM +0800, Chengming Zhou wrote: >> @@ -871,13 +861,23 @@ void psi_task_switch(struct task_struct *prev, struct task_struct *next, >> clear |= TSK_MEMSTALL_RUNNING; >> if (prev->in_iowait) >> set |= TSK_IOWAIT; >> + >> + /* >> + * Periodic aggregation shuts off if there is a period of no >> + * task changes, so we wake it back up if necessary. However, >> + * don't do this if the task change is the aggregation worker >> + * itself going to sleep, or we'll ping-pong forever. >> + */ >> + if (unlikely((prev->flags & PF_WQ_WORKER) && >> + wq_worker_last_func(prev) == psi_avgs_work)) >> + wake_clock = false; >> } >> >> psi_flags_change(prev, clear, set); >> >> iter = NULL; >> while ((group = iterate_groups(prev, &iter)) && group != common) >> - psi_group_change(group, cpu, clear, set, now, true); >> + psi_group_change(group, cpu, clear, set, now, wake_clock); >> >> /* >> * TSK_ONCPU is handled up to the common ancestor. If we're tasked > > Wait, there is another psi_group_change() below this, which handles > the clearing of TSK_RUNNING for common ancestors. We don't want to > wake those either, so it needs s/true/wake_clock/ as well. Yes, I was wrong, will fix. Thanks!
