Re: [PATCH v11 3/5] sched/core: uclamp: Propagate system defaults to root group

[Patrick Bellasi]

On 16-Jul 17:36, Michal Koutný wrote:
> On Tue, Jul 16, 2019 at 03:34:17PM +0100, Patrick Bellasi <patrick.bellasi@xxxxxxx> wrote:
> > > 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.
> When I responded to your other patch, it occurred to me that since
> cpu_util_update_eff goes writing down to child csses, it should take
> also uclamp_mutex here to avoid race with direct cgroup attribute
> writers.

Yep, I should drop the "dedicated" mutex we have now in
sysctl_sched_uclamp_handler() and use the uclamp_mutex we already
have.

Thanks, Patrick


-- 
#include <best/regards.h>

Patrick Bellasi