On Thu, Aug 17, 2017 at 09:51:34PM -0700, Joel Fernandes (Google) wrote: > On Thu, Aug 17, 2017 at 6:25 PM, Byungchul Park <byungchul.p...@lge.com> > wrote: > > On Mon, Aug 07, 2017 at 12:50:32PM +0900, Byungchul Park wrote: > >> When cpudl_find() returns any among free_cpus, the cpu might not be > >> closer than others, considering sched domain. For example: > >> > >> this_cpu: 15 > >> free_cpus: 0, 1,..., 14 (== later_mask) > >> best_cpu: 0 > >> > >> topology: > >> > >> 0 --+ > >> +--+ > >> 1 --+ | > >> +-- ... --+ > >> 2 --+ | | > >> +--+ | > >> 3 --+ | > >> > >> ... ... > >> > >> 12 --+ | > >> +--+ | > >> 13 --+ | | > >> +-- ... -+ > >> 14 --+ | > >> +--+ > >> 15 --+ > >> > >> In this case, it would be best to select 14 since it's a free cpu and > >> closest to 15(this_cpu). However, currently the code select 0(best_cpu) > >> even though that's just any among free_cpus. Fix it. > > > > Could you let me know your opinions about this? > > Patch looks good to me, I would also add a comment ontop of > fallback_cpu (I think Steve mentioned similar thing at [1]) > > /* > * fallback is the closest CPU in the closest SD incase > * all domains are PREFER_SIBLING > */ > if (fallback_cpu == -1) > fallback_cpu = best_cpu; > > And clarify this in the commit message.
Right. I will add it. Thank you very much, Byungchul
