Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754466AbaBDOpb (ORCPT ); Tue, 4 Feb 2014 09:45:31 -0500 Received: from cantor2.suse.de ([195.135.220.15]:56456 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753409AbaBDOp1 (ORCPT ); Tue, 4 Feb 2014 09:45:27 -0500 Date: Tue, 4 Feb 2014 15:45:26 +0100 From: Michal Hocko To: Vladimir Davydov Cc: akpm@linux-foundation.org, rientjes@google.com, penberg@kernel.org, cl@linux.com, glommer@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, devel@openvz.org Subject: Re: [PATCH 2/8] memcg, slab: remove cgroup name from memcg cache names Message-ID: <20140204144526.GG4890@dhcp22.suse.cz> References: <90b34882d51b18a9dd557d24f6a377df1ba13945.1391356789.git.vdavydov@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <90b34882d51b18a9dd557d24f6a377df1ba13945.1391356789.git.vdavydov@parallels.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun 02-02-14 20:33:47, Vladimir Davydov wrote: > The cgroup name is not informative at all in case the cgroup hierarchy > is not flat. Besides, we can always find the memcg a particular cache > belongs to by its kmemcg id, which is now exported via "memory.kmem.id" > cgroup fs file for each memcg. > > So let's remove the cgroup name part from kmem caches names - it will > greatly simplify the call paths and make the code look clearer. > > Signed-off-by: Vladimir Davydov I guess this one doesn't make much sense withou 1/8, right? > --- > mm/memcontrol.c | 63 +++++++++++++----------------------------------------- > mm/slab_common.c | 6 +++++- > 2 files changed, 20 insertions(+), 49 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 91d242707404..3351c5b5486d 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -3405,44 +3405,6 @@ void mem_cgroup_destroy_cache(struct kmem_cache *cachep) > schedule_work(&cachep->memcg_params->destroy); > } > > -static struct kmem_cache *memcg_create_kmem_cache(struct mem_cgroup *memcg, > - struct kmem_cache *s) > -{ > - struct kmem_cache *new = NULL; > - static char *tmp_name = NULL; > - static DEFINE_MUTEX(mutex); /* protects tmp_name */ > - > - BUG_ON(!memcg_can_account_kmem(memcg)); > - > - mutex_lock(&mutex); > - /* > - * kmem_cache_create_memcg duplicates the given name and > - * cgroup_name for this name requires RCU context. > - * This static temporary buffer is used to prevent from > - * pointless shortliving allocation. > - */ > - if (!tmp_name) { > - tmp_name = kmalloc(PATH_MAX, GFP_KERNEL); > - if (!tmp_name) > - goto out; > - } > - > - rcu_read_lock(); > - snprintf(tmp_name, PATH_MAX, "%s(%d:%s)", s->name, > - memcg_cache_id(memcg), cgroup_name(memcg->css.cgroup)); > - rcu_read_unlock(); > - > - new = kmem_cache_create_memcg(memcg, tmp_name, s->object_size, s->align, > - (s->flags & ~SLAB_PANIC), s->ctor, s); > - if (new) > - new->allocflags |= __GFP_KMEMCG; > - else > - new = s; > -out: > - mutex_unlock(&mutex); > - return new; > -} > - > void kmem_cache_destroy_memcg_children(struct kmem_cache *s) > { > struct kmem_cache *c; > @@ -3489,12 +3451,6 @@ void kmem_cache_destroy_memcg_children(struct kmem_cache *s) > mutex_unlock(&activate_kmem_mutex); > } > > -struct create_work { > - struct mem_cgroup *memcg; > - struct kmem_cache *cachep; > - struct work_struct work; > -}; > - > static void mem_cgroup_destroy_all_caches(struct mem_cgroup *memcg) > { > struct kmem_cache *cachep; > @@ -3512,13 +3468,24 @@ static void mem_cgroup_destroy_all_caches(struct mem_cgroup *memcg) > mutex_unlock(&memcg->slab_caches_mutex); > } > > +struct create_work { > + struct mem_cgroup *memcg; > + struct kmem_cache *cachep; > + struct work_struct work; > +}; > + > static void memcg_create_cache_work_func(struct work_struct *w) > { > - struct create_work *cw; > + struct create_work *cw = container_of(w, struct create_work, work); > + struct mem_cgroup *memcg = cw->memcg; > + struct kmem_cache *s = cw->cachep; > + struct kmem_cache *new; > > - cw = container_of(w, struct create_work, work); > - memcg_create_kmem_cache(cw->memcg, cw->cachep); > - css_put(&cw->memcg->css); > + new = kmem_cache_create_memcg(memcg, s->name, s->object_size, s->align, > + (s->flags & ~SLAB_PANIC), s->ctor, s); > + if (new) > + new->allocflags |= __GFP_KMEMCG; > + css_put(&memcg->css); > kfree(cw); > } > > diff --git a/mm/slab_common.c b/mm/slab_common.c > index 1ec3c619ba04..152d9b118b7a 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -213,7 +213,11 @@ kmem_cache_create_memcg(struct mem_cgroup *memcg, const char *name, size_t size, > s->align = calculate_alignment(flags, align, size); > s->ctor = ctor; > > - s->name = kstrdup(name, GFP_KERNEL); > + if (!memcg) > + s->name = kstrdup(name, GFP_KERNEL); > + else > + s->name = kasprintf(GFP_KERNEL, "%s:%d", > + name, memcg_cache_id(memcg)); > if (!s->name) > goto out_free_cache; > > -- > 1.7.10.4 > -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/