Dear all, If using acpi-cpufreq instead, v4.6, v4.6-rc3, v4.7-rc3 can't reproduce the issue. It seems only intel_pstate is impacted.
Thanks, Jisheng ________________________________________ From: Jisheng Zhang Sent: Friday, June 17, 2016 23:53 To: Rafael J. Wysocki Cc: Peter Zijlstra; Paul E. McKenney; Rafael J. Wysocki; Viresh Kumar; linux...@vger.kernel.org; Linux Kernel Mailing List Subject: RE: regression caused by bb6ab52f2bef ("intel_pstate: Do not set utilization update hook too early") Dear Rafael, I used intel_pstate. I just tested v4.7-rc3, which should include commit 4578ee7e1def intel_pstate: Avoid unnecessary synchronize_sched() during initialization, I can still get the same wakeups, so it's not sufficient. Another clue maybe helpful, I found these top2 wakeup/s is consistent, e.g rcu_sched always gives about 10 wakeups/s, and tick_sched_timer gave 5.6-5.9 wakeups/s, 144.3 µs/s 10.0 Process [rcu_sched] 193.9 µs/s 5.7 Timer tick_sched_timer Thanks, Jisheng ________________________________________ From: Rafael J. Wysocki Sent: Friday, June 17, 2016 23:42 To: Jisheng Zhang Cc: Peter Zijlstra; Paul E. McKenney; Rafael J. Wysocki; Viresh Kumar; linux...@vger.kernel.org; Linux Kernel Mailing List Subject: Re: regression caused by bb6ab52f2bef ("intel_pstate: Do not set utilization update hook too early") On Fri, Jun 17, 2016 at 5:40 PM, Rafael J. Wysocki wrote: > On Fri, Jun 17, 2016 at 5:32 PM, Jisheng Zhang wrote: >> Hi all, >> >> First of all, sorry for top post, only webmail is available now. >> >> Second, sorry again for report incorrect commit, I were too tired this >> morning so I remember the wrong commit. The regression is caused by >> bb6ab52f2bef ("intel_pstate: Do not set utilization update hook too early"), >> so I update the email title. > > OK, that makes much more sense. :-) > > And > > 4578ee7e1def intel_pstate: Avoid unnecessary synchronize_sched() > during initialization > > is not sufficient I suppose? I mean, it is not sufficient to reduce the number of wakeups again?