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| author | Rafael Aquini <aquini@redhat.com> | 2012-03-09 17:27:27 -0300 |
|---|---|---|
| committer | Pekka Enberg <penberg@kernel.org> | 2012-03-10 10:45:17 +0200 |
| commit | 8bdec192b40cf7f7eec170b317c76089eb5eeddb (patch) | |
| tree | 78bf7e353438b4ebe26b494e50d26111dc87d0d5 /mm/slab.c | |
| parent | a8203725dfded5c1f79dca3368a4a273e24b59bb (diff) | |
| download | lwn-8bdec192b40cf7f7eec170b317c76089eb5eeddb.tar.gz lwn-8bdec192b40cf7f7eec170b317c76089eb5eeddb.zip | |
mm: SLAB Out-of-memory diagnostics
Following the example at mm/slub.c, add out-of-memory diagnostics to the
SLAB allocator to help on debugging certain OOM conditions.
An example print out looks like this:
<snip page allocator out-of-memory message>
SLAB: Unable to allocate memory on node 0 (gfp=0x11200)
cache: bio-0, object size: 192, order: 0
node 0: slabs: 3/3, objs: 60/60, free: 0
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Diffstat (limited to 'mm/slab.c')
| -rw-r--r-- | mm/slab.c | 51 |
1 files changed, 50 insertions, 1 deletions
diff --git a/mm/slab.c b/mm/slab.c index 806a754fad8e..67e0e0589267 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1731,6 +1731,52 @@ static int __init cpucache_init(void) } __initcall(cpucache_init); +static noinline void +slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid) +{ + struct kmem_list3 *l3; + struct slab *slabp; + unsigned long flags; + int node; + + printk(KERN_WARNING + "SLAB: Unable to allocate memory on node %d (gfp=0x%x)\n", + nodeid, gfpflags); + printk(KERN_WARNING " cache: %s, object size: %d, order: %d\n", + cachep->name, cachep->buffer_size, cachep->gfporder); + + for_each_online_node(node) { + unsigned long active_objs = 0, num_objs = 0, free_objects = 0; + unsigned long active_slabs = 0, num_slabs = 0; + + l3 = cachep->nodelists[node]; + if (!l3) + continue; + + spin_lock_irqsave(&l3->list_lock, flags); + list_for_each_entry(slabp, &l3->slabs_full, list) { + active_objs += cachep->num; + active_slabs++; + } + list_for_each_entry(slabp, &l3->slabs_partial, list) { + active_objs += slabp->inuse; + active_slabs++; + } + list_for_each_entry(slabp, &l3->slabs_free, list) + num_slabs++; + + free_objects += l3->free_objects; + spin_unlock_irqrestore(&l3->list_lock, flags); + + num_slabs += active_slabs; + num_objs = num_slabs * cachep->num; + printk(KERN_WARNING + " node %d: slabs: %ld/%ld, objs: %ld/%ld, free: %ld\n", + node, active_slabs, num_slabs, active_objs, num_objs, + free_objects); + } +} + /* * Interface to system's page allocator. No need to hold the cache-lock. * @@ -1757,8 +1803,11 @@ static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) flags |= __GFP_RECLAIMABLE; page = alloc_pages_exact_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder); - if (!page) + if (!page) { + if (!(flags & __GFP_NOWARN) && printk_ratelimit()) + slab_out_of_memory(cachep, flags, nodeid); return NULL; + } nr_pages = (1 << cachep->gfporder); if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |