Since commit 2139cbe627b8 ("cma: fix counting of isolated pages") free pages in isolated pageblocks are not accounted to NR_FREE_PAGES counters, so watermarks check is not required if one operates on a free page in isolated pageblock.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- mm/page_alloc.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fd154fe..43ab09f 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1394,10 +1394,12 @@ int capture_free_page(struct page *page, int alloc_order, int migratetype) zone = page_zone(page); order = page_order(page);
- /* Obey watermarks as if the page was being allocated */ - watermark = low_wmark_pages(zone) + (1 << order); - if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) - return 0; + if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE) { + /* Obey watermarks as if the page was being allocated */ + watermark = low_wmark_pages(zone) + (1 << order); + if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) + return 0; + }
/* Remove page from free list */ list_del(&page->lru);