From: "Michal Koutný" <mkoutny@suse.com>
To: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
linux-api@vger.kernel.org, cgroups@vger.kernel.org,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>, Tejun Heo <tj@kernel.org>,
"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Viresh Kumar <viresh.kumar@linaro.org>,
Paul Turner <pjt@google.com>,
Quentin Perret <quentin.perret@arm.com>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Morten Rasmussen <morten.rasmussen@arm.com>,
Juri Lelli <juri.lelli@redhat.com>, Todd Kjos <tkjos@google.com>,
Joel Fernandes <joelaf@google.com>,
Steve Muckle <smuckle@google.com>,
Suren Baghdasaryan <surenb@google.com>,
Alessio Balsini <balsini@android.com>
Subject: Re: [PATCH v13 2/6] sched/core: uclamp: Propagate parent clamps
Date: Tue, 6 Aug 2019 18:11:53 +0200 [thread overview]
Message-ID: <20190806161153.GA19991@blackbody.suse.cz> (raw)
In-Reply-To: <20190802090853.4810-3-patrick.bellasi@arm.com>
[-- Attachment #1: Type: text/plain, Size: 932 bytes --]
On Fri, Aug 02, 2019 at 10:08:49AM +0100, Patrick Bellasi <patrick.bellasi@arm.com> wrote:
> @@ -7095,6 +7149,7 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf,
> if (req.ret)
> return req.ret;
>
> + mutex_lock(&uclamp_mutex);
> rcu_read_lock();
>
> tg = css_tg(of_css(of));
> @@ -7107,7 +7162,11 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf,
> */
> tg->uclamp_pct[clamp_id] = req.percent;
>
> + /* Update effective clamps to track the most restrictive value */
> + cpu_util_update_eff(of_css(of));
> +
> rcu_read_unlock();
> + mutex_unlock(&uclamp_mutex);
Following my remarks to "[PATCH v13 1/6] sched/core: uclamp: Extend
CPU's cgroup", I wonder if the rcu_read_lock() couldn't be moved right
before cpu_util_update_eff(). And by extension rcu_read_(un)lock could
be hidden into cpu_util_update_eff() closer to its actual need.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next prev parent reply other threads:[~2019-08-06 16:12 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-02 9:08 [PATCH v13 0/6] Add utilization clamping support (CGroups API) Patrick Bellasi
2019-08-02 9:08 ` [PATCH v13 1/6] sched/core: uclamp: Extend CPU's cgroup controller Patrick Bellasi
2019-08-06 16:11 ` Michal Koutný
2019-08-08 15:10 ` Patrick Bellasi
2019-08-08 17:19 ` Michal Koutný
2019-08-02 9:08 ` [PATCH v13 2/6] sched/core: uclamp: Propagate parent clamps Patrick Bellasi
2019-08-06 16:11 ` Michal Koutný [this message]
2019-08-08 15:08 ` Patrick Bellasi
2019-08-08 17:16 ` Michal Koutný
2019-08-02 9:08 ` [PATCH v13 3/6] sched/core: uclamp: Propagate system defaults to root group Patrick Bellasi
2019-08-02 9:08 ` [PATCH v13 4/6] sched/core: uclamp: Use TG's clamps to restrict TASK's clamps Patrick Bellasi
2019-08-02 9:08 ` [PATCH v13 5/6] sched/core: uclamp: Update CPU's refcount on TG's clamp changes Patrick Bellasi
2019-08-02 9:08 ` [PATCH v13 6/6] sched/core: uclamp: always use enum uclamp_id for clamp_id values Patrick Bellasi
2019-08-06 16:12 ` [PATCH v13 0/6] Add utilization clamping support (CGroups API) Michal Koutný
2019-08-06 16:40 ` Patrick Bellasi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190806161153.GA19991@blackbody.suse.cz \
--to=mkoutny@suse.com \
--cc=balsini@android.com \
--cc=cgroups@vger.kernel.org \
--cc=dietmar.eggemann@arm.com \
--cc=joelaf@google.com \
--cc=juri.lelli@redhat.com \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=morten.rasmussen@arm.com \
--cc=patrick.bellasi@arm.com \
--cc=peterz@infradead.org \
--cc=pjt@google.com \
--cc=quentin.perret@arm.com \
--cc=rafael.j.wysocki@intel.com \
--cc=smuckle@google.com \
--cc=surenb@google.com \
--cc=tj@kernel.org \
--cc=tkjos@google.com \
--cc=vincent.guittot@linaro.org \
--cc=viresh.kumar@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).