On 08-Mar 10:48, Peter Zijlstra wrote: > On Thu, Feb 22, 2018 at 05:01:53PM +0000, Patrick Bellasi wrote: > > +#define UTIL_EST_NEED_UPDATE_FLAG 0x1 > > > @@ -5321,12 +5345,19 @@ static inline void util_est_dequeue(struct cfs_rq > > *cfs_rq, > > if (!task_sleep) > > return; > > > > + /* > > + * Skip update of task's estimated utilization if the PELT signal has > > + * never been updated (at least once) since last enqueue time. > > + */ > > + ue = READ_ONCE(p->se.avg.util_est); > > + if (ue.enqueued & UTIL_EST_NEED_UPDATE_FLAG) > > + return; > > The name and function seem inverted, if the flag is set, we do _NOT_ > update util_est.
My reading was along the line "when the flag is set we need an update of util_avg to collect a new util_est sample"... ... but I agree that's confusing... and unnecessary long. > How about something like UTIL_EST_UNCHANGED ? That would give: I would prefer UTIL_AVG_UNCHANGED, since the flags is reset when we have a change in util_avg, thus enabling util_est updates. > /* > * If the PELT values haven't changed since enqueue time, > * skip the util_est update. > */ > if (enqueue & UTIL_EST_UNCHANGED) > return; -- #include <best/regards.h> Patrick Bellasi
