summaryrefslogtreecommitdiff
path: root/mm/failslab.c
diff options
context:
space:
mode:
authorNicolas Boichat <drinkcat@chromium.org>2019-07-12 06:55:03 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-12 21:05:43 +0300
commita9659476d4b391aec3f5357f176b63b9f8c46231 (patch)
treebf4725f93941912a40c89b14cfd81131a2a37ad1 /mm/failslab.c
parentf445884562dd8bc51eb4136bd21f014403d1813d (diff)
downloadlinux-a9659476d4b391aec3f5357f176b63b9f8c46231.tar.xz
mm/failslab.c: by default, do not fail allocations with direct reclaim only
When failslab was originally written, the intention of the "ignore-gfp-wait" flag default value ("N") was to fail GFP_ATOMIC allocations. Those were defined as (__GFP_HIGH), and the code would test for __GFP_WAIT (0x10u). However, since then, __GFP_WAIT was replaced by __GFP_RECLAIM (___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM), and GFP_ATOMIC is now defined as (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM). This means that when the flag is false, almost no allocation ever fails (as even GFP_ATOMIC allocations contain ___GFP_KSWAPD_RECLAIM). Restore the original intent of the code, by ignoring calls that directly reclaim only (__GFP_DIRECT_RECLAIM), and thus, failing GFP_ATOMIC calls again by default. Link: http://lkml.kernel.org/r/20190520214514.81360-1-drinkcat@chromium.org Fixes: 71baba4b92dc1fa1 ("mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM") Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/failslab.c')
-rw-r--r--mm/failslab.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/mm/failslab.c b/mm/failslab.c
index ec5aad211c5b..f92fed91ac23 100644
--- a/mm/failslab.c
+++ b/mm/failslab.c
@@ -23,7 +23,8 @@ bool __should_failslab(struct kmem_cache *s, gfp_t gfpflags)
if (gfpflags & __GFP_NOFAIL)
return false;
- if (failslab.ignore_gfp_reclaim && (gfpflags & __GFP_RECLAIM))
+ if (failslab.ignore_gfp_reclaim &&
+ (gfpflags & __GFP_DIRECT_RECLAIM))
return false;
if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))