vmscan: change shrinker API by passing shrink_control struct
Change each shrinker's API by consolidating the existing parameters into
shrink_control struct. This will simplify any further features added w/o
touching each file of shrinker.
[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: fix warning]
[kosaki.motohiro@jp.fujitsu.com: fix up new shrinker API]
[akpm@linux-foundation.org: fix xfs warning]
[akpm@linux-foundation.org: update gfs2]
Signed-off-by: Ying Han <yinghan@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 32cfa96..5cbbf78 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1166,18 +1166,20 @@
* We consolidate the values for easier extention later.
*/
struct shrink_control {
- unsigned long nr_scanned;
gfp_t gfp_mask;
+
+ /* How many slab objects shrinker() should scan and try to reclaim */
+ unsigned long nr_to_scan;
};
/*
* A callback you can register to apply pressure to ageable caches.
*
- * 'shrink' is passed a count 'nr_to_scan' and a 'gfpmask'. It should
- * look through the least-recently-used 'nr_to_scan' entries and
- * attempt to free them up. It should return the number of objects
- * which remain in the cache. If it returns -1, it means it cannot do
- * any scanning at this time (eg. there is a risk of deadlock).
+ * 'sc' is passed shrink_control which includes a count 'nr_to_scan'
+ * and a 'gfpmask'. It should look through the least-recently-used
+ * 'nr_to_scan' entries and attempt to free them up. It should return
+ * the number of objects which remain in the cache. If it returns -1, it means
+ * it cannot do any scanning at this time (eg. there is a risk of deadlock).
*
* The 'gfpmask' refers to the allocation we are currently trying to
* fulfil.
@@ -1186,7 +1188,7 @@
* querying the cache size, so a fastpath for that case is appropriate.
*/
struct shrinker {
- int (*shrink)(struct shrinker *, int nr_to_scan, gfp_t gfp_mask);
+ int (*shrink)(struct shrinker *, struct shrink_control *sc);
int seeks; /* seeks to recreate an obj */
/* These are for internal use */
@@ -1640,7 +1642,8 @@
int drop_caches_sysctl_handler(struct ctl_table *, int,
void __user *, size_t *, loff_t *);
unsigned long shrink_slab(struct shrink_control *shrink,
- unsigned long lru_pages);
+ unsigned long nr_pages_scanned,
+ unsigned long lru_pages);
#ifndef CONFIG_MMU
#define randomize_va_space 0