On 24/06/20 18:26, Qais Yousef wrote:
> struct uclamp_rq was zeroed out entirely in assumption that in the first
> call to uclamp_rq_inc() they'd be initialized correctly in accordance to
> default settings.
>
> But when next patch introduces a static key to skip
> uclamp_rq_{inc,dec}() until userspace opts in to use uclamp, schedutil
> will fail to perform any frequency changes because the
> rq->uclamp[UCLAMP_MAX].value is zeroed at init and stays as such. Which
> means all rqs are capped to 0 by default.
>
> Fix it by making sure we do proper initialization at init without
> relying on uclamp_rq_inc() doing it later.
>
> Fixes: 69842cba9ace ("sched/uclamp: Add CPU's clamp buckets refcounting")
> Signed-off-by: Qais Yousef <qais.you...@arm.com>
> Cc: Juri Lelli <juri.le...@redhat.com>
> Cc: Vincent Guittot <vincent.guit...@linaro.org>
> Cc: Dietmar Eggemann <dietmar.eggem...@arm.com>
> Cc: Steven Rostedt <rost...@goodmis.org>
> Cc: Ben Segall <bseg...@google.com>
> Cc: Mel Gorman <mgor...@suse.de>
> CC: Patrick Bellasi <patrick.bell...@matbug.net>
> Cc: Chris Redpath <chris.redp...@arm.com>
> Cc: Lukasz Luba <lukasz.l...@arm.com>
> Cc: linux-kernel@vger.kernel.orgReviewed-by: Valentin Schneider <valentin.schnei...@arm.com>
