From 647757197cd34fae041e21af39ded00f5c346fc4 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Tue, 14 Apr 2015 15:47:07 -0700 Subject: [PATCH] mm: clarify __GFP_NOFAIL deprecation status __GFP_NOFAIL is documented as a deprecated flag since commit 478352e789f5 ("mm: add comment about deprecation of __GFP_NOFAIL"). This has discouraged people from using it but in some cases an opencoded endless loop around allocator has been used instead. So the allocator is not aware of the de facto __GFP_NOFAIL allocation because this information was not communicated properly. Let's make clear that if the allocation context really cannot afford failure because there is no good failure policy then using __GFP_NOFAIL is preferable to opencoding the loop outside of the allocator. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michal Hocko Acked-by: David Rientjes Cc: Johannes Weiner Cc: Dave Chinner Cc: "Theodore Ts'o" Cc: Mel Gorman Cc: Tetsuo Handa Cc: "David S. Miller" Cc: Vipul Pandya Cc: Jan Kara Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/gfp.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 4423a0f8eabe..97a9373e61e8 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -57,8 +57,10 @@ struct vm_area_struct; * _might_ fail. This depends upon the particular VM implementation. * * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller - * cannot handle allocation failures. This modifier is deprecated and no new - * users should be added. + * cannot handle allocation failures. New users should be evaluated carefully + * (and the flag should be used only when there is no reasonable failure policy) + * but it is definitely preferable to use the flag rather than opencode endless + * loop around allocator. * * __GFP_NORETRY: The VM implementation must not retry indefinitely. *