[PATCH] mm: micro optimise zone_watermark_ok
Having min be a signed quantity means gcc can't turn high latency divides
into shifts. There happen to be two such divides for GFP_ATOMIC (ie.
networking, ie. important) allocations, one of which depends on the other.
Fixing this makes code smaller as a bonus.
Shame on somebody (probably me).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4f59d90..b5468de 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -900,7 +900,8 @@
int classzone_idx, int alloc_flags)
{
/* free_pages my go negative - that's OK */
- long min = mark, free_pages = z->free_pages - (1 << order) + 1;
+ unsigned long min = mark;
+ long free_pages = z->free_pages - (1 << order) + 1;
int o;
if (alloc_flags & ALLOC_HIGH)