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| author | Ravikiran G Thirumalai <kiran@scalex86.org> | 2006-02-10 01:51:13 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-02-10 08:13:12 -0800 |
| commit | f0188f47482efdbd2e005103bb4f0224a835dfad (patch) | |
| tree | 4d08110ea4560b433eecb4fa4de05dae6ea103e9 | |
| parent | 8e36709d8cea48a4d341294ce2b46678a2e77159 (diff) | |
| download | lwn-f0188f47482efdbd2e005103bb4f0224a835dfad.tar.gz lwn-f0188f47482efdbd2e005103bb4f0224a835dfad.zip | |
[PATCH] slab: Avoid deadlock at kmem_cache_create/kmem_cache_destroy
Prevents deadlock situation between
kmem_cache_create()/kmem_cache_destory(), and kmem_cache_create() /cpu
hotplug. The locking order probably got moved over time.
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | mm/slab.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/mm/slab.c b/mm/slab.c index d66c2b0d9715..add05d808a4a 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1717,6 +1717,12 @@ kmem_cache_create (const char *name, size_t size, size_t align, BUG(); } + /* + * Prevent CPUs from coming and going. + * lock_cpu_hotplug() nests outside cache_chain_mutex + */ + lock_cpu_hotplug(); + mutex_lock(&cache_chain_mutex); list_for_each(p, &cache_chain) { @@ -1918,8 +1924,6 @@ kmem_cache_create (const char *name, size_t size, size_t align, cachep->dtor = dtor; cachep->name = name; - /* Don't let CPUs to come and go */ - lock_cpu_hotplug(); if (g_cpucache_up == FULL) { enable_cpucache(cachep); @@ -1978,12 +1982,12 @@ kmem_cache_create (const char *name, size_t size, size_t align, /* cache setup completed, link it into the list */ list_add(&cachep->next, &cache_chain); - unlock_cpu_hotplug(); oops: if (!cachep && (flags & SLAB_PANIC)) panic("kmem_cache_create(): failed to create slab `%s'\n", name); mutex_unlock(&cache_chain_mutex); + unlock_cpu_hotplug(); return cachep; } EXPORT_SYMBOL(kmem_cache_create); |