On 26-07-17, 22:34, Joel Fernandes (Google) wrote: > On Wed, Jul 26, 2017 at 2:22 AM, Viresh Kumar <viresh.ku...@linaro.org> wrote: > > @@ -221,7 +226,7 @@ static void sugov_update_single(struct update_util_data > > *hook, u64 time, > > sugov_set_iowait_boost(sg_cpu, time, flags); > > sg_cpu->last_update = time; > > > > - if (!sugov_should_update_freq(sg_policy, time)) > > + if (!sugov_should_update_freq(sg_policy, time, hook->cpu)) > > return; > > Since with the remote callbacks now possible, isn't it unsafe to > modify sg_cpu and sg_policy structures without a lock in > sugov_update_single? > > Unlike sugov_update_shared, we don't acquire any lock in > sugov_update_single before updating these structures. Did I miss > something?
As Peter already mentioned it earlier, the callbacks are called with rq locks held and so sugov_update_single() wouldn't get called in parallel for a target CPU. That's the only race you were worried about ? -- viresh
