On Tue, May 31, 2016 at 12:41:21PM +0200, Peter Zijlstra wrote: > On Tue, May 31, 2016 at 09:31:32AM +0800, Yuyang Du wrote: > > On Tue, May 31, 2016 at 11:21:46AM +0200, Peter Zijlstra wrote: > > > On Tue, May 31, 2016 at 09:11:37AM +0800, Yuyang Du wrote: > > > > The SD_BALANCE_WAKE is irrelevant in the contexts of these two removals, > > > > and in addition SD_BALANCE_WAKE is not and should not be set in any > > > > sched_domain flags so far. > > > > > > This Changelog doesn't make any sense... > > > > How? SD_BALANCE_WAKE is not in any sched_domain flags (sd->flags), even if > > it is, it is not used anywhere, no? > > It is and it is. See select_task_fair_rq(): > > if (tmp->flags & sd_flags) > > Now, as long as WAKE_AFFINE is also set, its hard to actually get into > the find_idlest_cpu() balancing, but if you clear all that you will > still get there. Well, that is very true, and the next patch (2/2) just makes all this what this is supposed to be: the SD_BALANCE_WAKE is a meaningful sched_domain flag.
This particular patch is a pure cleanup, may I amend the changelog to: According to the comment: "turn off/on idle balance on this domain", the SD_BALANCE_WAKE has nothing to do with idle balance, so clean them up.
