+ mm-zone_reclaim-make-isolate_lru_page-filter-aware.patch added to -mm tree

+ mm-zone_reclaim-make-isolate_lru_page-filter-aware.patch added to -mm tree

[akpm]

The patch titled
     mm: zone_reclaim: make isolate_lru_page() filter-aware
has been added to the -mm tree.  Its filename is
     mm-zone_reclaim-make-isolate_lru_page-filter-aware.patch

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------------------------------------------------------
Subject: mm: zone_reclaim: make isolate_lru_page() filter-aware
From: Minchan Kim <minchan.kim@gmail.com>

In __zone_reclaim case, we don't want to shrink mapped page.  Nonetheless,
we have isolated mapped page and re-add it into LRU's head.  It's
unnecessary CPU overhead and makes LRU churning.

Of course, when we isolate the page, the page might be mapped but when we
try to migrate the page, the page would be not mapped.  So it could be
migrated.  But race is rare and although it happens, it's no big deal.

Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/mmzone.h |    3 +++
 mm/vmscan.c            |   20 ++++++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff -puN include/linux/mmzone.h~mm-zone_reclaim-make-isolate_lru_page-filter-aware include/linux/mmzone.h
--- a/include/linux/mmzone.h~mm-zone_reclaim-make-isolate_lru_page-filter-aware
+++ a/include/linux/mmzone.h
@@ -170,6 +170,9 @@ static inline int is_unevictable_lru(enu
 #define ISOLATE_ACTIVE		((__force fmode_t)0x2)
 /* Isolate clean file */
 #define ISOLATE_CLEAN		((__force fmode_t)0x4)
+/* Isolate unmapped file */
+#define ISOLATE_UNMAPPED	((__force fmode_t)0x8)
+
 /* LRU Isolation modes. */
 typedef unsigned __bitwise__ isolate_mode_t;
 
diff -puN mm/vmscan.c~mm-zone_reclaim-make-isolate_lru_page-filter-aware mm/vmscan.c
--- a/mm/vmscan.c~mm-zone_reclaim-make-isolate_lru_page-filter-aware
+++ a/mm/vmscan.c
@@ -1049,6 +1049,9 @@ int __isolate_lru_page(struct page *page
 	if ((mode & ISOLATE_CLEAN) && (PageDirty(page) || PageWriteback(page)))
 		return ret;
 
+	if ((mode & ISOLATE_UNMAPPED) && page_mapped(page))
+		return ret;
+
 	if (likely(get_page_unless_zero(page))) {
 		/*
 		 * Be careful not to clear PageLRU until after we're
@@ -1478,6 +1481,12 @@ shrink_inactive_list(unsigned long nr_to
 		reclaim_mode |= ISOLATE_ACTIVE;
 
 	lru_add_drain();
+
+	if (!sc->may_unmap)
+		reclaim_mode |= ISOLATE_UNMAPPED;
+	if (!sc->may_writepage)
+		reclaim_mode |= ISOLATE_CLEAN;
+
 	spin_lock_irq(&zone->lru_lock);
 
 	if (scanning_global_lru(sc)) {
@@ -1598,19 +1607,26 @@ static void shrink_active_list(unsigned 
 	struct page *page;
 	struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
 	unsigned long nr_rotated = 0;
+	isolate_mode_t reclaim_mode = ISOLATE_ACTIVE;
 
 	lru_add_drain();
+
+	if (!sc->may_unmap)
+		reclaim_mode |= ISOLATE_UNMAPPED;
+	if (!sc->may_writepage)
+		reclaim_mode |= ISOLATE_CLEAN;
+
 	spin_lock_irq(&zone->lru_lock);
 	if (scanning_global_lru(sc)) {
 		nr_taken = isolate_pages_global(nr_pages, &l_hold,
 						&pgscanned, sc->order,
-						ISOLATE_ACTIVE, zone,
+						reclaim_mode, zone,
 						1, file);
 		zone->pages_scanned += pgscanned;
 	} else {
 		nr_taken = mem_cgroup_isolate_pages(nr_pages, &l_hold,
 						&pgscanned, sc->order,
-						ISOLATE_ACTIVE, zone,
+						reclaim_mode, zone,
 						sc->mem_cgroup, 1, file);
 		/*
 		 * mem_cgroup_isolate_pages() keeps track of
_

Patches currently in -mm which might be from minchan.kim@gmail.com are

origin.patch
mm-compaction-trivial-clean-up-in-acct_isolated.patch
mm-change-isolate-mode-from-define-to-bitwise-type.patch
mm-compaction-make-isolate_lru_page-filter-aware.patch
mm-zone_reclaim-make-isolate_lru_page-filter-aware.patch
mm-migration-clean-up-unmap_and_move.patch