Commit eeee9a8c authored Jan 07, 2009 by KOSAKI Motohiro Committed by Linus Torvalds Jan 08, 2009

mm: make get_scan_ratio() safe for memcg



Currently, get_scan_ratio() always calculate the balancing value for
global reclaim and memcg reclaim doesn't use it.  Therefore it doesn't
have scan_global_lru() condition.

However, we plan to expand get_scan_ratio() to be usable for memcg too,
latter.  Then, The dependency code of global reclaim in the
get_scan_ratio() insert into scan_global_lru() condision explictly.

This patch doesn't have any functional change.

Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent c9f299d9

mm/vmscan.c

+9 −6

Original line number	Diff line number	Diff line
		@@ -1376,14 +1376,17 @@ static void get_scan_ratio(struct zone zone, struct scan_control sc,
		zone_nr_pages(zone, sc, LRU_INACTIVE_ANON);
		file = zone_nr_pages(zone, sc, LRU_ACTIVE_FILE) +
		zone_nr_pages(zone, sc, LRU_INACTIVE_FILE);
		free = zone_page_state(zone, NR_FREE_PAGES);

		/* If we have very few page cache pages, force-scan anon pages. */
		if (scan_global_lru(sc)) {
		free = zone_page_state(zone, NR_FREE_PAGES);
		/* If we have very few page cache pages,
		force-scan anon pages. */
		if (unlikely(file + free <= zone->pages_high)) {
		percent[0] = 100;
		percent[1] = 0;
		return;
		}
		}

		/*
		* OK, so we have swap space and a fair amount of page cache