diff options
author | Mel Gorman <mgorman@techsingularity.net> | 2021-06-28 19:42:21 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-06-29 10:53:54 -0700 |
commit | c49c2c47dab6b8d45022b3fabf0642a0e62e3109 (patch) | |
tree | 4a5929d0291298c04a6b8af7958ce77bbca64bb9 /mm/page_alloc.c | |
parent | 3b12e7e97938424de2bb1b95ba0bd6a49bad39f9 (diff) | |
download | linux-c49c2c47dab6b8d45022b3fabf0642a0e62e3109.tar.bz2 |
mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
When kswapd is active then direct reclaim is potentially active. In
either case, it is possible that a zone would be balanced if pages were
not trapped on PCP lists. Instead of draining remote pages, simply limit
the size of the PCP lists while kswapd is active.
Link: https://lkml.kernel.org/r/20210525080119.5455-6-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/page_alloc.c')
-rw-r--r-- | mm/page_alloc.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e1d1825a2611..adf35ccfd8e5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3302,6 +3302,23 @@ static int nr_pcp_free(struct per_cpu_pages *pcp, int high, int batch) return batch; } +static int nr_pcp_high(struct per_cpu_pages *pcp, struct zone *zone) +{ + int high = READ_ONCE(pcp->high); + + if (unlikely(!high)) + return 0; + + if (!test_bit(ZONE_RECLAIM_ACTIVE, &zone->flags)) + return high; + + /* + * If reclaim is active, limit the number of pages that can be + * stored on pcp lists + */ + return min(READ_ONCE(pcp->batch) << 2, high); +} + static void free_unref_page_commit(struct page *page, unsigned long pfn, int migratetype) { @@ -3313,7 +3330,7 @@ static void free_unref_page_commit(struct page *page, unsigned long pfn, pcp = this_cpu_ptr(zone->per_cpu_pageset); list_add(&page->lru, &pcp->lists[migratetype]); pcp->count++; - high = READ_ONCE(pcp->high); + high = nr_pcp_high(pcp, zone); if (pcp->count >= high) { int batch = READ_ONCE(pcp->batch); |