From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: [PATCH v3 14/28] slab: create duplicate cache Date: Fri, 25 May 2012 17:03:34 +0400 Message-ID: <1337951028-3427-15-git-send-email-glommer@parallels.com> References: <1337951028-3427-1-git-send-email-glommer@parallels.com> Return-path: In-Reply-To: <1337951028-3427-1-git-send-email-glommer-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org, Tejun Heo , Li Zefan , Greg Thelen , Suleiman Souhlal , Michal Hocko , Johannes Weiner , devel-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org, David Rientjes , Glauber Costa , Christoph Lameter , Pekka Enberg 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. [ v3: add get_online cpus before the slab mutex ] Signed-off-by: Glauber Costa Signed-off-by: Suleiman Souhlal CC: Christoph Lameter CC: Pekka Enberg CC: Michal Hocko CC: Kamezawa Hiroyuki CC: Johannes Weiner --- mm/slab.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 44 insertions(+), 0 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index 8bff32a1..e2227de 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 @@ -2616,6 +2618,42 @@ 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); + + get_online_cpus(); + 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) { + kfree(name); + 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); + put_online_cpus(); + return new; +} +#endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ + #if DEBUG static void check_irq_off(void) { @@ -2811,6 +2849,12 @@ void kmem_cache_destroy(struct kmem_cache *cachep) rcu_barrier(); mem_cgroup_release_cache(cachep); +#ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM + /* memcg cache: free the name string. Doing it here saves us + * a pointer to it outside the slab code */ + if (cachep->memcg_params.id == -1) + kfree(cachep->name); +#endif __kmem_cache_destroy(cachep); mutex_unlock(&cache_chain_mutex); -- 1.7.7.6