From: Pekka Enberg Date: Sat, 10 Feb 2007 09:42:53 +0000 (-0800) Subject: [PATCH] slab: cache alloc cleanups X-Git-Tag: v2.6.21-rc1~274^2~478 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8c8cc2c10c21943dd3499a2df7aac835093b37f3;p=linux-2.6 [PATCH] slab: cache alloc cleanups Clean up __cache_alloc and __cache_alloc_node functions a bit. We no longer need to do NUMA_BUILD tricks and the UMA allocation path is much simpler. No functional changes in this patch. Note: saves few kernel text bytes on x86 NUMA build due to using gotos in __cache_alloc_node() and moving __GFP_THISNODE check in to fallback_alloc(). Cc: Andy Whitcroft Cc: Christoph Hellwig Cc: Manfred Spraul Acked-by: Christoph Lameter Cc: Paul Jackson Signed-off-by: Pekka Enberg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/slab.c b/mm/slab.c index aea1cd2531..b595323e24 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -3189,35 +3189,6 @@ static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) return objp; } -static __always_inline void *__cache_alloc(struct kmem_cache *cachep, - gfp_t flags, void *caller) -{ - unsigned long save_flags; - void *objp = NULL; - - cache_alloc_debugcheck_before(cachep, flags); - - local_irq_save(save_flags); - - if (unlikely(NUMA_BUILD && - current->flags & (PF_SPREAD_SLAB | PF_MEMPOLICY))) - objp = alternate_node_alloc(cachep, flags); - - if (!objp) - objp = ____cache_alloc(cachep, flags); - /* - * We may just have run out of memory on the local node. - * ____cache_alloc_node() knows how to locate memory on other nodes - */ - if (NUMA_BUILD && !objp) - objp = ____cache_alloc_node(cachep, flags, numa_node_id()); - local_irq_restore(save_flags); - objp = cache_alloc_debugcheck_after(cachep, flags, objp, - caller); - prefetchw(objp); - return objp; -} - #ifdef CONFIG_NUMA /* * Try allocating on another node if PF_SPREAD_SLAB|PF_MEMPOLICY. @@ -3249,14 +3220,20 @@ static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) * allocator to do its reclaim / fallback magic. We then insert the * slab into the proper nodelist and then allocate from it. */ -void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) +static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags) { - struct zonelist *zonelist = &NODE_DATA(slab_node(current->mempolicy)) - ->node_zonelists[gfp_zone(flags)]; + struct zonelist *zonelist; + gfp_t local_flags; struct zone **z; void *obj = NULL; int nid; - gfp_t local_flags = (flags & GFP_LEVEL_MASK); + + if (flags & __GFP_THISNODE) + return NULL; + + zonelist = &NODE_DATA(slab_node(current->mempolicy)) + ->node_zonelists[gfp_zone(flags)]; + local_flags = (flags & GFP_LEVEL_MASK); retry: /* @@ -3366,16 +3343,110 @@ must_grow: if (x) goto retry; - if (!(flags & __GFP_THISNODE)) - /* Unable to grow the cache. Fall back to other nodes. */ - return fallback_alloc(cachep, flags); - - return NULL; + return fallback_alloc(cachep, flags); done: return obj; } -#endif + +/** + * kmem_cache_alloc_node - Allocate an object on the specified node + * @cachep: The cache to allocate from. + * @flags: See kmalloc(). + * @nodeid: node number of the target node. + * @caller: return address of caller, used for debug information + * + * Identical to kmem_cache_alloc but it will allocate memory on the given + * node, which can improve the performance for cpu bound structures. + * + * Fallback to other node is possible if __GFP_THISNODE is not set. + */ +static __always_inline void * +__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, + void *caller) +{ + unsigned long save_flags; + void *ptr; + + cache_alloc_debugcheck_before(cachep, flags); + local_irq_save(save_flags); + + if (unlikely(nodeid == -1)) + nodeid = numa_node_id(); + + if (unlikely(!cachep->nodelists[nodeid])) { + /* Node not bootstrapped yet */ + ptr = fallback_alloc(cachep, flags); + goto out; + } + + if (nodeid == numa_node_id()) { + /* + * Use the locally cached objects if possible. + * However ____cache_alloc does not allow fallback + * to other nodes. It may fail while we still have + * objects on other nodes available. + */ + ptr = ____cache_alloc(cachep, flags); + if (ptr) + goto out; + } + /* ___cache_alloc_node can fall back to other nodes */ + ptr = ____cache_alloc_node(cachep, flags, nodeid); + out: + local_irq_restore(save_flags); + ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, caller); + + return ptr; +} + +static __always_inline void * +__do_cache_alloc(struct kmem_cache *cache, gfp_t flags) +{ + void *objp; + + if (unlikely(current->flags & (PF_SPREAD_SLAB | PF_MEMPOLICY))) { + objp = alternate_node_alloc(cache, flags); + if (objp) + goto out; + } + objp = ____cache_alloc(cache, flags); + + /* + * We may just have run out of memory on the local node. + * ____cache_alloc_node() knows how to locate memory on other nodes + */ + if (!objp) + objp = ____cache_alloc_node(cache, flags, numa_node_id()); + + out: + return objp; +} +#else + +static __always_inline void * +__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags) +{ + return ____cache_alloc(cachep, flags); +} + +#endif /* CONFIG_NUMA */ + +static __always_inline void * +__cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller) +{ + unsigned long save_flags; + void *objp; + + cache_alloc_debugcheck_before(cachep, flags); + local_irq_save(save_flags); + objp = __do_cache_alloc(cachep, flags); + local_irq_restore(save_flags); + objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller); + prefetchw(objp); + + return objp; +} /* * Caller needs to acquire correct kmem_list's list_lock @@ -3574,57 +3645,6 @@ out: } #ifdef CONFIG_NUMA -/** - * kmem_cache_alloc_node - Allocate an object on the specified node - * @cachep: The cache to allocate from. - * @flags: See kmalloc(). - * @nodeid: node number of the target node. - * @caller: return address of caller, used for debug information - * - * Identical to kmem_cache_alloc but it will allocate memory on the given - * node, which can improve the performance for cpu bound structures. - * - * Fallback to other node is possible if __GFP_THISNODE is not set. - */ -static __always_inline void * -__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, - int nodeid, void *caller) -{ - unsigned long save_flags; - void *ptr = NULL; - - cache_alloc_debugcheck_before(cachep, flags); - local_irq_save(save_flags); - - if (unlikely(nodeid == -1)) - nodeid = numa_node_id(); - - if (likely(cachep->nodelists[nodeid])) { - if (nodeid == numa_node_id()) { - /* - * Use the locally cached objects if possible. - * However ____cache_alloc does not allow fallback - * to other nodes. It may fail while we still have - * objects on other nodes available. - */ - ptr = ____cache_alloc(cachep, flags); - } - if (!ptr) { - /* ___cache_alloc_node can fall back to other nodes */ - ptr = ____cache_alloc_node(cachep, flags, nodeid); - } - } else { - /* Node not bootstrapped yet */ - if (!(flags & __GFP_THISNODE)) - ptr = fallback_alloc(cachep, flags); - } - - local_irq_restore(save_flags); - ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, caller); - - return ptr; -} - void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) { return __cache_alloc_node(cachep, flags, nodeid,