diff options
Diffstat (limited to 'mm/slub.c')
| -rw-r--r-- | mm/slub.c | 76 |
1 files changed, 55 insertions, 21 deletions
diff --git a/mm/slub.c b/mm/slub.c index 4907563ef7ff..ffe13fdf8144 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -29,6 +29,7 @@ #include <linux/math64.h> #include <linux/fault-inject.h> #include <linux/stacktrace.h> +#include <linux/prefetch.h> #include <trace/events/kmem.h> @@ -269,6 +270,11 @@ static inline void *get_freepointer(struct kmem_cache *s, void *object) return *(void **)(object + s->offset); } +static void prefetch_freepointer(const struct kmem_cache *s, void *object) +{ + prefetch(object + s->offset); +} + static inline void *get_freepointer_safe(struct kmem_cache *s, void *object) { void *p; @@ -1560,6 +1566,7 @@ static void *get_partial_node(struct kmem_cache *s, } else { page->freelist = t; available = put_cpu_partial(s, page, 0); + stat(s, CPU_PARTIAL_NODE); } if (kmem_cache_debug(s) || available > s->cpu_partial / 2) break; @@ -1581,6 +1588,7 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags, struct zone *zone; enum zone_type high_zoneidx = gfp_zone(flags); void *object; + unsigned int cpuset_mems_cookie; /* * The defrag ratio allows a configuration of the tradeoffs between @@ -1604,23 +1612,32 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags, get_cycles() % 1024 > s->remote_node_defrag_ratio) return NULL; - get_mems_allowed(); - zonelist = node_zonelist(slab_node(current->mempolicy), flags); - for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { - struct kmem_cache_node *n; - - n = get_node(s, zone_to_nid(zone)); - - if (n && cpuset_zone_allowed_hardwall(zone, flags) && - n->nr_partial > s->min_partial) { - object = get_partial_node(s, n, c); - if (object) { - put_mems_allowed(); - return object; + do { + cpuset_mems_cookie = get_mems_allowed(); + zonelist = node_zonelist(slab_node(current->mempolicy), flags); + for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { + struct kmem_cache_node *n; + + n = get_node(s, zone_to_nid(zone)); + + if (n && cpuset_zone_allowed_hardwall(zone, flags) && + n->nr_partial > s->min_partial) { + object = get_partial_node(s, n, c); + if (object) { + /* + * Return the object even if + * put_mems_allowed indicated that + * the cpuset mems_allowed was + * updated in parallel. It's a + * harmless race between the alloc + * and the cpuset update. + */ + put_mems_allowed(cpuset_mems_cookie); + return object; + } } } - } - put_mems_allowed(); + } while (!put_mems_allowed(cpuset_mems_cookie)); #endif return NULL; } @@ -1973,6 +1990,7 @@ int put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) local_irq_restore(flags); pobjects = 0; pages = 0; + stat(s, CPU_PARTIAL_DRAIN); } } @@ -1984,7 +2002,6 @@ int put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) page->next = oldpage; } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage); - stat(s, CPU_PARTIAL_FREE); return pobjects; } @@ -2018,9 +2035,17 @@ static void flush_cpu_slab(void *d) __flush_cpu_slab(s, smp_processor_id()); } +static bool has_cpu_slab(int cpu, void *info) +{ + struct kmem_cache *s = info; + struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); + + return !!(c->page); +} + static void flush_all(struct kmem_cache *s) { - on_each_cpu(flush_cpu_slab, s, 1); + on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC); } /* @@ -2309,6 +2334,8 @@ redo: object = __slab_alloc(s, gfpflags, node, addr, c); else { + void *next_object = get_freepointer_safe(s, object); + /* * The cmpxchg will only match if there was no additional * operation and if we are on the right processor. @@ -2324,11 +2351,12 @@ redo: if (unlikely(!this_cpu_cmpxchg_double( s->cpu_slab->freelist, s->cpu_slab->tid, object, tid, - get_freepointer_safe(s, object), next_tid(tid)))) { + next_object, next_tid(tid)))) { note_cmpxchg_failure("slab_alloc", s, tid); goto redo; } + prefetch_freepointer(s, next_object); stat(s, ALLOC_FASTPATH); } @@ -2465,9 +2493,10 @@ static void __slab_free(struct kmem_cache *s, struct page *page, * If we just froze the page then put it onto the * per cpu partial list. */ - if (new.frozen && !was_frozen) + if (new.frozen && !was_frozen) { put_cpu_partial(s, page, 1); - + stat(s, CPU_PARTIAL_FREE); + } /* * The list lock was not taken therefore no list * activity can be necessary. @@ -3929,13 +3958,14 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size, if (kmem_cache_open(s, n, size, align, flags, ctor)) { list_add(&s->list, &slab_caches); + up_write(&slub_lock); if (sysfs_slab_add(s)) { + down_write(&slub_lock); list_del(&s->list); kfree(n); kfree(s); goto err; } - up_write(&slub_lock); return s; } kfree(n); @@ -5059,6 +5089,8 @@ STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail); STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail); STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc); STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); +STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); +STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); #endif static struct attribute *slab_attrs[] = { @@ -5124,6 +5156,8 @@ static struct attribute *slab_attrs[] = { &cmpxchg_double_cpu_fail_attr.attr, &cpu_partial_alloc_attr.attr, &cpu_partial_free_attr.attr, + &cpu_partial_node_attr.attr, + &cpu_partial_drain_attr.attr, #endif #ifdef CONFIG_FAILSLAB &failslab_attr.attr, |