From 136333d104bd3a62d783b0ac3d0f32ac0108c5d0 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Wed, 24 Aug 2011 08:57:52 +0800 Subject: [PATCH] slub: explicitly document position of inserting slab to partial list Adding slab to partial list head/tail is sensitive to performance. So explicitly uses DEACTIVATE_TO_TAIL/DEACTIVATE_TO_HEAD to document it to avoid we get it wrong. Acked-by: Christoph Lameter Signed-off-by: Shaohua Li Signed-off-by: Shaohua Li Signed-off-by: Pekka Enberg --- mm/slub.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 7c54fe83a90..91a120f185d 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1534,7 +1534,7 @@ static inline void add_partial(struct kmem_cache_node *n, struct page *page, int tail) { n->nr_partial++; - if (tail) + if (tail == DEACTIVATE_TO_TAIL) list_add_tail(&page->lru, &n->partial); else list_add(&page->lru, &n->partial); @@ -1781,13 +1781,13 @@ static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) enum slab_modes l = M_NONE, m = M_NONE; void *freelist; void *nextfree; - int tail = 0; + int tail = DEACTIVATE_TO_HEAD; struct page new; struct page old; if (page->freelist) { stat(s, DEACTIVATE_REMOTE_FREES); - tail = 1; + tail = DEACTIVATE_TO_TAIL; } c->tid = next_tid(c->tid); @@ -1893,7 +1893,7 @@ redo: if (m == M_PARTIAL) { add_partial(n, page, tail); - stat(s, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); + stat(s, tail); } else if (m == M_FULL) { @@ -2377,7 +2377,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page, */ if (unlikely(!prior)) { remove_full(s, page); - add_partial(n, page, 1); + add_partial(n, page, DEACTIVATE_TO_TAIL); stat(s, FREE_ADD_PARTIAL); } } @@ -2695,7 +2695,7 @@ static void early_kmem_cache_node_alloc(int node) init_kmem_cache_node(n, kmem_cache_node); inc_slabs_node(kmem_cache_node, node, page->objects); - add_partial(n, page, 0); + add_partial(n, page, DEACTIVATE_TO_HEAD); } static void free_kmem_cache_nodes(struct kmem_cache *s) -- 2.39.5