Messages in this thread | | | Date | Tue, 8 Sep 2015 17:22:40 +0900 | From | Byungchul Park <> | Subject | Re: [PATCH] sched: fix lose fair sleeper bonus in switch_to_fair() |
| |
On Tue, Sep 08, 2015 at 04:04:49PM +0800, Wanpeng Li wrote: > >>However, if se->vruntime -= cfs_rq->min_vruntime is positive, the > >>behavior is different after your patch. e.g. se->vruntime(the > >>relative vruntime in switched_to_fair()) < min_vruntime - > >>sysctl_sched_latency/2 > >> > >>before your patch: > >> > >>se->vruntime = min_vruntime - sysctl_sched_latency/2 (place_entity()) > >my patch is based on ff277d4 commit at tip/sched/core. > > > >there's no change between before and after. > > > >check it please. > > > >and this logic seems to be no problem to me. :( > > Your logic will lose fair sleeper bonus in the scenario which I pointed out.
i mean in ff277d4 commit:
se->vruntime += cfs->min_vruntime (switched_to_fair()) se->vruntime = se->vruntime or bonused value (place_entity())
after my patch:
se->vruntime += cfs->min_vruntime (switched_to_fair()) se->vruntime = se->vruntime or bonused value (place_entity())
---
SAME!!!
in addtion, se->vruntime already had a bonused value if eligible, when it was detached from cfs_rq.
> > > > >>after your patch: > >> > >>se->vruntime += cfs->min_vruntime (switched_to_fair()) > >>se->vruntime = se->vruntime (place_entity()) > >> > >> > >>Regards, > >>Wanpeng Li > >> > >>-- > >>To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > >>the body of a message to majordomo@vger.kernel.org > >>More majordomo info at http://vger.kernel.org/majordomo-info.html > >>Please read the FAQ at http://www.tux.org/lkml/ > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
| |