Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20190708084357.12944-1-patrick.bellasi@arm.com>
 <20190708084357.12944-4-patrick.bellasi@arm.com> <20190715164226.GA30262@blackbody.suse.cz>
 <20190716143417.us3xhksrsaxsl2ok@e110439-lin>
In-Reply-To: <20190716143417.us3xhksrsaxsl2ok@e110439-lin>
From:   Joel Fernandes <joelaf@google.com>
Date:   Tue, 16 Jul 2019 11:46:18 -0400
Message-ID: <CAJWu+opGqXG0shybpLvt5fXOe_UdoiXU-tNWjkWSrHmO+wtavw@mail.gmail.com>
Subject: Re: [PATCH v11 3/5] sched/core: uclamp: Propagate system defaults to
 root group
To:     Patrick Bellasi <patrick.bellasi@arm.com>
Cc:     =?UTF-8?Q?Michal_Koutn=C3=BD?= <mkoutny@suse.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux PM <linux-pm@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>,
        Steve Muckle <smuckle@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Alessio Balsini <balsini@android.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, Jul 16, 2019 at 10:34 AM Patrick Bellasi
<patrick.bellasi@arm.com> wrote:
>
> On 15-Jul 18:42, Michal Koutn=C3=BD wrote:
> > On Mon, Jul 08, 2019 at 09:43:55AM +0100, Patrick Bellasi <patrick.bell=
asi@arm.com> wrote:
> > > +static void uclamp_update_root_tg(void)
> > > +{
> > > +   struct task_group *tg =3D &root_task_group;
> > > +
> > > +   uclamp_se_set(&tg->uclamp_req[UCLAMP_MIN],
> > > +                 sysctl_sched_uclamp_util_min, false);
> > > +   uclamp_se_set(&tg->uclamp_req[UCLAMP_MAX],
> > > +                 sysctl_sched_uclamp_util_max, false);
> > > +
> > > +   cpu_util_update_eff(&root_task_group.css);
> > > +}
> > cpu_util_update_eff internally calls css_for_each_descendant_pre() so
> > this should be protected with rcu_read_lock().
>
> Right, good catch! Will add in v12.
>

Hopefully these can catch it in the near future!
https://lore.kernel.org/rcu/20190715143705.117908-1-joel@joelfernandes.org/=
T/#t