diff options
| -rw-r--r-- | include/linux/slab.h | 57 | ||||
| -rw-r--r-- | include/linux/slob_def.h | 8 | ||||
| -rw-r--r-- | init/Kconfig | 11 | ||||
| -rw-r--r-- | mm/slab.c | 51 | ||||
| -rw-r--r-- | mm/slab.h | 3 | ||||
| -rw-r--r-- | mm/slab_common.c | 18 | ||||
| -rw-r--r-- | mm/slob.c | 4 | ||||
| -rw-r--r-- | mm/slub.c | 38 |
8 files changed, 121 insertions, 69 deletions
diff --git a/include/linux/slab.h b/include/linux/slab.h index 0c62175..6c5cc0e 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -169,11 +169,7 @@ struct kmem_cache { struct list_head list; /* List of all slab caches on the system */ }; -#define KMALLOC_MAX_SIZE (1UL << 30) - -#include <linux/slob_def.h> - -#else /* CONFIG_SLOB */ +#endif /* CONFIG_SLOB */ /* * Kmalloc array related definitions @@ -195,7 +191,9 @@ struct kmem_cache { #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif -#else +#endif + +#ifdef CONFIG_SLUB /* * SLUB allocates up to order 2 pages directly and otherwise * passes the request to the page allocator. @@ -207,6 +205,19 @@ struct kmem_cache { #endif #endif +#ifdef CONFIG_SLOB +/* + * SLOB passes all page size and larger requests to the page allocator. + * No kmalloc array is necessary since objects of different sizes can + * be allocated from the same page. + */ +#define KMALLOC_SHIFT_MAX 30 +#define KMALLOC_SHIFT_HIGH PAGE_SHIFT +#ifndef KMALLOC_SHIFT_LOW +#define KMALLOC_SHIFT_LOW 3 +#endif +#endif + /* Maximum allocatable size */ #define KMALLOC_MAX_SIZE (1UL << KMALLOC_SHIFT_MAX) /* Maximum size for which we actually use a slab cache */ @@ -221,6 +232,7 @@ struct kmem_cache { #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW) #endif +#ifndef CONFIG_SLOB extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1]; #ifdef CONFIG_ZONE_DMA extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1]; @@ -275,13 +287,18 @@ static __always_inline int kmalloc_index(size_t size) /* Will never be reached. Needed because the compiler may complain */ return -1; } +#endif /* !CONFIG_SLOB */ #ifdef CONFIG_SLAB #include <linux/slab_def.h> -#elif defined(CONFIG_SLUB) +#endif + +#ifdef CONFIG_SLUB #include <linux/slub_def.h> -#else -#error "Unknown slab allocator" +#endif + +#ifdef CONFIG_SLOB +#include <linux/slob_def.h> #endif /* @@ -291,6 +308,7 @@ static __always_inline int kmalloc_index(size_t size) */ static __always_inline int kmalloc_size(int n) { +#ifndef CONFIG_SLOB if (n > 2) return 1 << n; @@ -299,10 +317,9 @@ static __always_inline int kmalloc_size(int n) if (n == 2 && KMALLOC_MIN_SIZE <= 64) return 192; - +#endif return 0; } -#endif /* !CONFIG_SLOB */ /* * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment. @@ -356,9 +373,8 @@ int cache_show(struct kmem_cache *s, struct seq_file *m); void print_slabinfo_header(struct seq_file *m); /** - * kmalloc_array - allocate memory for an array. - * @n: number of elements. - * @size: element size. + * kmalloc - allocate memory + * @size: how many bytes of memory are required. * @flags: the type of memory to allocate. * * The @flags argument may be one of: @@ -405,6 +421,17 @@ void print_slabinfo_header(struct seq_file *m); * There are other flags available as well, but these are not intended * for general use, and so are not documented here. For a full list of * potential flags, always refer to linux/gfp.h. + * + * kmalloc is the normal method of allocating memory + * in the kernel. + */ +static __always_inline void *kmalloc(size_t size, gfp_t flags); + +/** + * kmalloc_array - allocate memory for an array. + * @n: number of elements. + * @size: element size. + * @flags: the type of memory to allocate (see kmalloc). */ static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags) { @@ -428,7 +455,7 @@ static inline void *kcalloc(size_t n, size_t size, gfp_t flags) /** * kmalloc_node - allocate memory from a specific node * @size: how many bytes of memory are required. - * @flags: the type of memory to allocate (see kcalloc). + * @flags: the type of memory to allocate (see kmalloc). * @node: node to allocate from. * * kmalloc() for non-local nodes, used to allocate from a specific node diff --git a/include/linux/slob_def.h b/include/linux/slob_def.h index f28e14a..095a5a4 100644 --- a/include/linux/slob_def.h +++ b/include/linux/slob_def.h @@ -18,14 +18,6 @@ static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node) return __kmalloc_node(size, flags, node); } -/** - * kmalloc - allocate memory - * @size: how many bytes of memory are required. - * @flags: the type of memory to allocate (see kcalloc). - * - * kmalloc is the normal method of allocating memory - * in the kernel. - */ static __always_inline void *kmalloc(size_t size, gfp_t flags) { return __kmalloc_node(size, flags, NUMA_NO_NODE); diff --git a/init/Kconfig b/init/Kconfig index 54d3fa5..247084b 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1596,6 +1596,17 @@ config SLOB endchoice +config SLUB_CPU_PARTIAL + default y + depends on SLUB + bool "SLUB per cpu partial cache" + help + Per cpu partial caches accellerate objects allocation and freeing + that is local to a processor at the price of more indeterminism + in the latency of the free. On overflow these caches will be cleared + which requires the taking of locks that may cause latency spikes. + Typically one would choose no for a realtime system. + config MMAP_ALLOW_UNINITIALIZED bool "Allow mmapped anonymous memory to be uninitialized" depends on EXPERT && !MMU @@ -565,7 +565,7 @@ static void init_node_lock_keys(int q) if (slab_state < UP) return; - for (i = 1; i < PAGE_SHIFT + MAX_ORDER; i++) { + for (i = 1; i <= KMALLOC_SHIFT_HIGH; i++) { struct kmem_cache_node *n; struct kmem_cache *cache = kmalloc_caches[i]; @@ -1180,6 +1180,12 @@ static int init_cache_node_node(int node) return 0; } +static inline int slabs_tofree(struct kmem_cache *cachep, + struct kmem_cache_node *n) +{ + return (n->free_objects + cachep->num - 1) / cachep->num; +} + static void __cpuinit cpuup_canceled(long cpu) { struct kmem_cache *cachep; @@ -1241,7 +1247,7 @@ free_array_cache: n = cachep->node[node]; if (!n) continue; - drain_freelist(cachep, n, n->free_objects); + drain_freelist(cachep, n, slabs_tofree(cachep, n)); } } @@ -1408,7 +1414,7 @@ static int __meminit drain_cache_node_node(int node) if (!n) continue; - drain_freelist(cachep, n, n->free_objects); + drain_freelist(cachep, n, slabs_tofree(cachep, n)); if (!list_empty(&n->slabs_full) || !list_empty(&n->slabs_partial)) { @@ -2532,7 +2538,7 @@ static int __cache_shrink(struct kmem_cache *cachep) if (!n) continue; - drain_freelist(cachep, n, n->free_objects); + drain_freelist(cachep, n, slabs_tofree(cachep, n)); ret += !list_empty(&n->slabs_full) || !list_empty(&n->slabs_partial); @@ -3338,18 +3344,6 @@ done: return obj; } -/** - * 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 * slab_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid, unsigned long caller) @@ -3643,6 +3637,17 @@ EXPORT_SYMBOL(kmem_cache_alloc_trace); #endif #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. + * + * 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. + */ void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) { void *ret = slab_alloc_node(cachep, flags, nodeid, _RET_IP_); @@ -4431,20 +4436,10 @@ static int leaks_show(struct seq_file *m, void *p) return 0; } -static void *s_next(struct seq_file *m, void *p, loff_t *pos) -{ - return seq_list_next(p, &slab_caches, pos); -} - -static void s_stop(struct seq_file *m, void *p) -{ - mutex_unlock(&slab_mutex); -} - static const struct seq_operations slabstats_op = { .start = leaks_start, - .next = s_next, - .stop = s_stop, + .next = slab_next, + .stop = slab_stop, .show = leaks_show, }; @@ -271,3 +271,6 @@ struct kmem_cache_node { #endif }; + +void *slab_next(struct seq_file *m, void *p, loff_t *pos); +void slab_stop(struct seq_file *m, void *p); diff --git a/mm/slab_common.c b/mm/slab_common.c index 2d41450..538bade 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -497,6 +497,13 @@ void __init create_kmalloc_caches(unsigned long flags) #ifdef CONFIG_SLABINFO + +#ifdef CONFIG_SLAB +#define SLABINFO_RIGHTS (S_IWUSR | S_IRUSR) +#else +#define SLABINFO_RIGHTS S_IRUSR +#endif + void print_slabinfo_header(struct seq_file *m) { /* @@ -531,12 +538,12 @@ static void *s_start(struct seq_file *m, loff_t *pos) return seq_list_start(&slab_caches, *pos); } -static void *s_next(struct seq_file *m, void *p, loff_t *pos) +void *slab_next(struct seq_file *m, void *p, loff_t *pos) { return seq_list_next(p, &slab_caches, pos); } -static void s_stop(struct seq_file *m, void *p) +void slab_stop(struct seq_file *m, void *p) { mutex_unlock(&slab_mutex); } @@ -613,8 +620,8 @@ static int s_show(struct seq_file *m, void *p) */ static const struct seq_operations slabinfo_op = { .start = s_start, - .next = s_next, - .stop = s_stop, + .next = slab_next, + .stop = slab_stop, .show = s_show, }; @@ -633,7 +640,8 @@ static const struct file_operations proc_slabinfo_operations = { static int __init slab_proc_init(void) { - proc_create("slabinfo", S_IRUSR, NULL, &proc_slabinfo_operations); + proc_create("slabinfo", SLABINFO_RIGHTS, NULL, + &proc_slabinfo_operations); return 0; } module_init(slab_proc_init); @@ -122,7 +122,7 @@ static inline void clear_slob_page_free(struct page *sp) } #define SLOB_UNIT sizeof(slob_t) -#define SLOB_UNITS(size) (((size) + SLOB_UNIT - 1)/SLOB_UNIT) +#define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) /* * struct slob_rcu is inserted at the tail of allocated slob blocks, which @@ -554,7 +554,7 @@ void *kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) flags, node); } - if (c->ctor) + if (b && c->ctor) c->ctor(b); kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); @@ -123,6 +123,15 @@ static inline int kmem_cache_debug(struct kmem_cache *s) #endif } +static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s) +{ +#ifdef CONFIG_SLUB_CPU_PARTIAL + return !kmem_cache_debug(s); +#else + return false; +#endif +} + /* * Issues still to be resolved: * @@ -1573,7 +1582,8 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n, put_cpu_partial(s, page, 0); stat(s, CPU_PARTIAL_NODE); } - if (kmem_cache_debug(s) || available > s->cpu_partial / 2) + if (!kmem_cache_has_cpu_partial(s) + || available > s->cpu_partial / 2) break; } @@ -1884,6 +1894,7 @@ redo: static void unfreeze_partials(struct kmem_cache *s, struct kmem_cache_cpu *c) { +#ifdef CONFIG_SLUB_CPU_PARTIAL struct kmem_cache_node *n = NULL, *n2 = NULL; struct page *page, *discard_page = NULL; @@ -1938,6 +1949,7 @@ static void unfreeze_partials(struct kmem_cache *s, discard_slab(s, page); stat(s, FREE_SLAB); } +#endif } /* @@ -1951,10 +1963,14 @@ static void unfreeze_partials(struct kmem_cache *s, */ static void put_cpu_partial(struct kmem_cache *s, struct page *page, int drain) { +#ifdef CONFIG_SLUB_CPU_PARTIAL struct page *oldpage; int pages; int pobjects; + if (!s->cpu_partial) + return; + do { pages = 0; pobjects = 0; @@ -1987,6 +2003,7 @@ static void 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); +#endif } static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) @@ -2358,7 +2375,7 @@ redo: object = c->freelist; page = c->page; - if (unlikely(!object || !node_match(page, node))) + if (unlikely(!object || !page || !node_match(page, node))) object = __slab_alloc(s, gfpflags, node, addr, c); else { @@ -2495,7 +2512,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page, new.inuse--; if ((!new.inuse || !prior) && !was_frozen) { - if (!kmem_cache_debug(s) && !prior) + if (kmem_cache_has_cpu_partial(s) && !prior) /* * Slab was on no list before and will be partially empty @@ -2550,8 +2567,9 @@ static void __slab_free(struct kmem_cache *s, struct page *page, * Objects left in the slab. If it was not on the partial list before * then add it. */ - if (kmem_cache_debug(s) && unlikely(!prior)) { - remove_full(s, page); + if (!kmem_cache_has_cpu_partial(s) && unlikely(!prior)) { + if (kmem_cache_debug(s)) + remove_full(s, page); add_partial(n, page, DEACTIVATE_TO_TAIL); stat(s, FREE_ADD_PARTIAL); } @@ -3059,7 +3077,7 @@ static int kmem_cache_open(struct kmem_cache *s, unsigned long flags) * per node list when we run out of per cpu objects. We only fetch 50% * to keep some capacity around for frees. */ - if (kmem_cache_debug(s)) + if (!kmem_cache_has_cpu_partial(s)) s->cpu_partial = 0; else if (s->size >= PAGE_SIZE) s->cpu_partial = 2; @@ -4456,7 +4474,7 @@ static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf, err = strict_strtoul(buf, 10, &objects); if (err) return err; - if (objects && kmem_cache_debug(s)) + if (objects && !kmem_cache_has_cpu_partial(s)) return -EINVAL; s->cpu_partial = objects; @@ -5269,7 +5287,6 @@ __initcall(slab_sysfs_init); #ifdef CONFIG_SLABINFO void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) { - unsigned long nr_partials = 0; unsigned long nr_slabs = 0; unsigned long nr_objs = 0; unsigned long nr_free = 0; @@ -5281,9 +5298,8 @@ void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo) if (!n) continue; - nr_partials += n->nr_partial; - nr_slabs += atomic_long_read(&n->nr_slabs); - nr_objs += atomic_long_read(&n->total_objects); + nr_slabs += node_nr_slabs(n); + nr_objs += node_nr_objs(n); nr_free += count_partial(n, count_free); } |
