Merge "mm: vmscan: only write dirty pages that the scanner has seen twice" (20fa9d7f) · Commits · e / devices / android_kernel_fairphone_FP3

mm/vmscan.c

+10 −6

Original line number	Diff line number	Diff line
		@@ -1154,14 +1154,18 @@ static unsigned long shrink_page_list(struct list_head *page_list,

		if (PageDirty(page)) {
		/*
		* Only kswapd can writeback filesystem pages to
		* avoid risk of stack overflow but only writeback
		* if many dirty pages have been encountered.
		* Only kswapd can writeback filesystem pages
		* to avoid risk of stack overflow. But avoid
		* injecting inefficient single-page IO into
		* flusher writeback as much as possible: only
		* write pages when we've encountered many
		* dirty pages, and when we've already scanned
		* the rest of the LRU for clean pages and see
		* the same dirty pages again (PageReclaim).
		*/
		if (page_is_file_cache(page) &&
		(!current_is_kswapd() \|\|
		(pgdat &&
		!test_bit(PGDAT_DIRTY, &pgdat->flags)))) {
		(!current_is_kswapd() \|\| !PageReclaim(page) \|\|
		!test_bit(PGDAT_DIRTY, &pgdat->flags))) {
		/*
		* Immediately reclaim when written back.
		* Similar in principal to deactivate_page()