From 20cea9683ecc6dd75a80c0dd02dc69c64e95be75 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Fri, 6 Jul 2012 15:25:13 -0500 Subject: [PATCH] mm, sl[aou]b: Move kmem_cache_create mutex handling to common code Move the mutex handling into the common kmem_cache_create() function. Then we can also move more checks out of SLAB's kmem_cache_create() into the common code. Reviewed-by: Glauber Costa Signed-off-by: Christoph Lameter Signed-off-by: Pekka Enberg --- mm/slab.c | 52 +--------------------------------------------------- mm/slab_common.c | 41 ++++++++++++++++++++++++++++++++++++++++- mm/slub.c | 28 +++++++++++++--------------- 3 files changed, 54 insertions(+), 67 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index fd7dac6..1fcf3ac 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2228,55 +2228,10 @@ __kmem_cache_create (const char *name, size_t size, size_t align, unsigned long flags, void (*ctor)(void *)) { size_t left_over, slab_size, ralign; - struct kmem_cache *cachep = NULL, *pc; + struct kmem_cache *cachep = NULL; gfp_t gfp; - /* - * Sanity checks... these are all serious usage bugs. - */ - if (!name || in_interrupt() || (size < BYTES_PER_WORD) || - size > KMALLOC_MAX_SIZE) { - printk(KERN_ERR "%s: Early error in slab %s\n", __func__, - name); - BUG(); - } - - /* - * We use cache_chain_mutex to ensure a consistent view of - * cpu_online_mask as well. Please see cpuup_callback - */ - if (slab_is_available()) { - get_online_cpus(); - mutex_lock(&slab_mutex); - } - - list_for_each_entry(pc, &slab_caches, list) { - char tmp; - int res; - - /* - * This happens when the module gets unloaded and doesn't - * destroy its slab cache and no-one else reuses the vmalloc - * area of the module. Print a warning. - */ - res = probe_kernel_address(pc->name, tmp); - if (res) { - printk(KERN_ERR - "SLAB: cache with size %d has lost its name\n", - pc->size); - continue; - } - - if (!strcmp(pc->name, name)) { - printk(KERN_ERR - "kmem_cache_create: duplicate cache %s\n", name); - dump_stack(); - goto oops; - } - } - #if DEBUG - WARN_ON(strchr(name, ' ')); /* It confuses parsers */ #if FORCED_DEBUG /* * Enable redzoning and last user accounting, except for caches with @@ -2495,11 +2450,6 @@ __kmem_cache_create (const char *name, size_t size, size_t align, /* cache setup completed, link it into the list */ list_add(&cachep->list, &slab_caches); -oops: - if (slab_is_available()) { - mutex_unlock(&slab_mutex); - put_online_cpus(); - } return cachep; } diff --git a/mm/slab_common.c b/mm/slab_common.c index 50e1ff1..12637ce 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -11,7 +11,8 @@ #include #include #include - +#include +#include #include #include #include @@ -61,8 +62,46 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size, size_t align } #endif + get_online_cpus(); + mutex_lock(&slab_mutex); + +#ifdef CONFIG_DEBUG_VM + list_for_each_entry(s, &slab_caches, list) { + char tmp; + int res; + + /* + * This happens when the module gets unloaded and doesn't + * destroy its slab cache and no-one else reuses the vmalloc + * area of the module. Print a warning. + */ + res = probe_kernel_address(s->name, tmp); + if (res) { + printk(KERN_ERR + "Slab cache with size %d has lost its name\n", + s->object_size); + continue; + } + + if (!strcmp(s->name, name)) { + printk(KERN_ERR "kmem_cache_create(%s): Cache name" + " already exists.\n", + name); + dump_stack(); + s = NULL; + goto oops; + } + } + + WARN_ON(strchr(name, ' ')); /* It confuses parsers */ +#endif + s = __kmem_cache_create(name, size, align, flags, ctor); +oops: + mutex_unlock(&slab_mutex); + put_online_cpus(); + #ifdef CONFIG_DEBUG_VM out: #endif diff --git a/mm/slub.c b/mm/slub.c index 8c4fd37..0e0504e 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3911,7 +3911,6 @@ struct kmem_cache *__kmem_cache_create(const char *name, size_t size, struct kmem_cache *s; char *n; - mutex_lock(&slab_mutex); s = find_mergeable(size, align, flags, name, ctor); if (s) { s->refcount++; @@ -3924,37 +3923,36 @@ struct kmem_cache *__kmem_cache_create(const char *name, size_t size, if (sysfs_slab_alias(s, name)) { s->refcount--; - goto err; + return NULL; } - mutex_unlock(&slab_mutex); return s; } n = kstrdup(name, GFP_KERNEL); if (!n) - goto err; + return NULL; s = kmalloc(kmem_size, GFP_KERNEL); if (s) { if (kmem_cache_open(s, n, size, align, flags, ctor)) { + int r; + list_add(&s->list, &slab_caches); mutex_unlock(&slab_mutex); - if (sysfs_slab_add(s)) { - mutex_lock(&slab_mutex); - list_del(&s->list); - kfree(n); - kfree(s); - goto err; - } - return s; + r = sysfs_slab_add(s); + mutex_lock(&slab_mutex); + + if (!r) + return s; + + list_del(&s->list); + kmem_cache_close(s); } kfree(s); } kfree(n); -err: - mutex_unlock(&slab_mutex); - return s; + return NULL; } #ifdef CONFIG_SMP -- 2.7.4