On (03/26/15 16:39), Minchan Kim wrote: > Hello Sergey, > > Sorry for slow response. > I am overwhelmed with too much to do. :( > Hello, sure, no problem. > > > diff -puN mm/zsmalloc.c~zsmalloc-remove-extra-cond_resched-in-__zs_compact mm/zsmalloc.c > > > --- a/mm/zsmalloc.c~zsmalloc-remove-extra-cond_resched-in-__zs_compact > > > +++ a/mm/zsmalloc.c > > > @@ -1717,8 +1717,6 @@ static unsigned long __zs_compact(struct > > > struct page *dst_page = NULL; > > > unsigned long nr_total_migrated = 0; > > > > > > - cond_resched(); > > > - > > > spin_lock(&class->lock); > > > while ((src_page = isolate_source_page(class))) { > > If we removed cond_resched out of outer loop(ie, your patch), we lose > the chance to reschedule if alloc_target_page fails(ie, there is no > zspage in ZS_ALMOST_FULL and ZS_ALMOST_EMPTY). in outer loop we have preemption enabled and unlocked class. wouldn't that help? (hm, UP system?) > It might be not rare event if we does compation successfully for a > size_class. However, with next coming higher size_class for __zs_compact, > we will encounter cond_resched during compaction. > So, I am happy to ack. :) > > Acked-by: Minchan Kim <minchan@xxxxxxxxxx> thanks! -ss -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>