This patch provides kmem_cache_dup(), that duplicates a cache for a memcg, preserving its creation properties. Object size, alignment and flags are all respected. An exception is the SLAB_PANIC flag, since cache creation inside a memcg should not be fatal.
This code is mostly written by Suleiman Souhlal, with some adaptations and simplifications by me. Signed-off-by: Glauber Costa <[email protected]> CC: Christoph Lameter <[email protected]> CC: Pekka Enberg <[email protected]> CC: Michal Hocko <[email protected]> CC: Kamezawa Hiroyuki <[email protected]> CC: Johannes Weiner <[email protected]> CC: Suleiman Souhlal <[email protected]> --- mm/slab.c | 32 ++++++++++++++++++++++++++++++++ 1 files changed, 32 insertions(+), 0 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index d05a326..985714a 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -301,6 +301,8 @@ static void free_block(struct kmem_cache *cachep, void **objpp, int len, int node); static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp); static void cache_reap(struct work_struct *unused); +static int do_tune_cpucache(struct kmem_cache *cachep, int limit, + int batchcount, int shared, gfp_t gfp); /* * This function must be completely optimized away if a constant is passed to @@ -2598,6 +2600,36 @@ kmem_cache_create(const char *name, size_t size, size_t align, EXPORT_SYMBOL(kmem_cache_create); #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM +struct kmem_cache *kmem_cache_dup(struct mem_cgroup *memcg, + struct kmem_cache *cachep) +{ + struct kmem_cache *new; + unsigned long flags; + char *name; + + name = mem_cgroup_cache_name(memcg, cachep); + if (!name) + return NULL; + + flags = cachep->flags & ~(SLAB_PANIC|CFLGS_OFF_SLAB); + mutex_lock(&cache_chain_mutex); + new = __kmem_cache_create(memcg, name, obj_size(cachep), + cachep->memcg_params.orig_align, flags, cachep->ctor); + + if (new == NULL) + goto out; + + if ((cachep->limit != new->limit) || + (cachep->batchcount != new->batchcount) || + (cachep->shared != new->shared)) + do_tune_cpucache(new, cachep->limit, cachep->batchcount, + cachep->shared, GFP_KERNEL); +out: + mutex_unlock(&cache_chain_mutex); + kfree(name); + return new; +} + static int __init memcg_slab_register_all(void) { struct kmem_cache *cachep; -- 1.7.7.6 _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
