| Message ID | 20220803025121.47018-1-wuyun.abel@bytedance.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/page_alloc: only search higher order when fallback | expand |
On 8/3/22 04:51, Abel Wu wrote: > It seems unnecessary to search pages with order < alloc_order in > fallback allocation. This can currently happen with ALLOC_NOFRAGMENT and alloc_order > pageblock_order, so add a test to prevent it. > Signed-off-by: Abel Wu <wuyun.abel@bytedance.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> > --- > mm/page_alloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index e008a3df0485..0abafc2fc3e0 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -2934,7 +2934,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, > * i.e. orders < pageblock_order. If there are no local zones free, > * the zonelists will be reiterated without ALLOC_NOFRAGMENT. > */ > - if (alloc_flags & ALLOC_NOFRAGMENT) > + if (order < pageblock_order && alloc_flags & ALLOC_NOFRAGMENT) > min_order = pageblock_order; > > /*
On Wed, Aug 3, 2022 at 10:51 AM Abel Wu <wuyun.abel@bytedance.com> wrote: > > It seems unnecessary to search pages with order < alloc_order in > fallback allocation. > > Signed-off-by: Abel Wu <wuyun.abel@bytedance.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Thanks.
On Wed, Aug 03, 2022 at 10:51:21AM +0800, Abel Wu wrote: > It seems unnecessary to search pages with order < alloc_order in > fallback allocation. > > Signed-off-by: Abel Wu <wuyun.abel@bytedance.com> Acked-by: Mel Gorman <mgorman@techsingularity.net>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e008a3df0485..0abafc2fc3e0 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2934,7 +2934,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, * i.e. orders < pageblock_order. If there are no local zones free, * the zonelists will be reiterated without ALLOC_NOFRAGMENT. */ - if (alloc_flags & ALLOC_NOFRAGMENT) + if (order < pageblock_order && alloc_flags & ALLOC_NOFRAGMENT) min_order = pageblock_order; /*
It seems unnecessary to search pages with order < alloc_order in fallback allocation. Signed-off-by: Abel Wu <wuyun.abel@bytedance.com> --- mm/page_alloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)