From 8e125cd85517c9716695b0abfabc0a4a3fcb94f3 Mon Sep 17 00:00:00 2001
From: Minchan Kim <minchan@kernel.org>
Date: Tue, 31 Jul 2012 16:43:16 -0700
Subject: [PATCH] vmscan: remove obsolete shrink_control comment
09f363c7 ("vmscan: fix shrinker callback bug in fs/super.c") fixed a
shrinker callback which was returning -1 when nr_to_scan is zero, which
caused excessive slab scanning. But 635697c6 ("vmscan: fix initial
shrinker size handling") fixed the problem, again so we can freely return
-1 although nr_to_scan is zero. So let's revert 09f363c7 because the
comment added in 09f363c7 made an unnecessary rule.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
fs/super.c | 2 +-
include/linux/shrinker.h | 1 -
2 files changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/super.c b/fs/super.c
index 4c5d82f56ec4..4bf714459a4b 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -62,7 +62,7 @@ static int prune_super(struct shrinker *shrink, struct shrink_control *sc)
return -1;
if (!grab_super_passive(sb))
- return !sc->nr_to_scan ? 0 : -1;
+ return -1;
if (sb->s_op && sb->s_op->nr_cached_objects)
fs_objects = sb->s_op->nr_cached_objects(sb);
diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h
index 07ceb97d53fa..ac6b8ee07825 100644
--- a/include/linux/shrinker.h
+++ b/include/linux/shrinker.h
@@ -20,7 +20,6 @@ struct shrink_control {
* '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 callback must not return -1 if nr_to_scan is zero.
*
* The 'gfpmask' refers to the allocation we are currently trying to
* fulfil.
--
GitLab