From e838a45f9392a5bd2be1cd3ab0b16ae85857461c Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Fri, 24 Jun 2016 14:49:37 -0700 Subject: [PATCH] mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask Commit d0164adc89f6 ("mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd") modified __GFP_WAIT to explicitly identify the difference between atomic callers and those that were unwilling to sleep. Later the definition was removed entirely. The GFP_RECLAIM_MASK is the set of flags that affect watermark checking and reclaim behaviour but __GFP_ATOMIC was never added. Without it, atomic users of the slab allocator strip the __GFP_ATOMIC flag and cannot access the page allocator atomic reserves. This patch addresses the problem. The user-visible impact depends on the workload but potentially atomic allocations unnecessarily fail without this path. Link: http://lkml.kernel.org/r/20160610093832.GK2527@techsingularity.net Signed-off-by: Mel Gorman Reported-by: Marcin Wojtas Acked-by: Vlastimil Babka Acked-by: Michal Hocko Cc: [4.4+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/internal.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/internal.h b/mm/internal.h index a37e5b6f9d25..2524ec880e24 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -24,7 +24,8 @@ */ #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\ __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\ - __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC) + __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\ + __GFP_ATOMIC) /* The GFP flags allowed during early boot */ #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))