From b2455396be35383c4eebc6745cc718b1dd9e23df Mon Sep 17 00:00:00 2001 From: Paul Jackson Date: Fri, 24 Mar 2006 03:16:12 -0800 Subject: [PATCH] [PATCH] cpuset: memory_spread_slab drop useless PF_SPREAD_PAGE check The hook in the slab cache allocation path to handle cpuset memory spreading for tasks in cpusets with 'memory_spread_slab' enabled has a modest performance bug. The hook calls into the memory spreading handler alternate_node_alloc() if either of 'memory_spread_slab' or 'memory_spread_page' is enabled, even though the handler does nothing (albeit harmlessly) for the page case Fix - drop PF_SPREAD_PAGE from the set of flag bits that are used to trigger a call to alternate_node_alloc(). The page case is handled by separate hooks -- see the calls conditioned on cpuset_do_page_mem_spread() in mm/filemap.c Signed-off-by: Paul Jackson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/slab.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index f80b523..26138c9 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2809,8 +2809,7 @@ static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) struct array_cache *ac; #ifdef CONFIG_NUMA - if (unlikely(current->flags & (PF_SPREAD_PAGE | PF_SPREAD_SLAB | - PF_MEMPOLICY))) { + if (unlikely(current->flags & (PF_SPREAD_SLAB | PF_MEMPOLICY))) { objp = alternate_node_alloc(cachep, flags); if (objp != NULL) return objp; @@ -2849,7 +2848,7 @@ static __always_inline void *__cache_alloc(struct kmem_cache *cachep, #ifdef CONFIG_NUMA /* - * Try allocating on another node if PF_SPREAD_PAGE|PF_SPREAD_SLAB|PF_MEMPOLICY. + * Try allocating on another node if PF_SPREAD_SLAB|PF_MEMPOLICY. * * If we are in_interrupt, then process context, including cpusets and * mempolicy, may not apply and should not be used for allocation policy. -- 2.7.4