From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx113.postini.com [74.125.245.113]) by kanga.kvack.org (Postfix) with SMTP id E8B576B005C for ; Wed, 27 Jun 2012 00:01:35 -0400 (EDT) Received: by dakp5 with SMTP id p5so928650dak.14 for ; Tue, 26 Jun 2012 21:01:35 -0700 (PDT) Date: Tue, 26 Jun 2012 21:01:32 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH 06/11] memcg: kmem controller infrastructure In-Reply-To: <4FE97E31.3010201@parallels.com> Message-ID: References: <1340633728-12785-1-git-send-email-glommer@parallels.com> <1340633728-12785-7-git-send-email-glommer@parallels.com> <4FE97E31.3010201@parallels.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: cgroups@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, Frederic Weisbecker , Pekka Enberg , Michal Hocko , Johannes Weiner , Christoph Lameter , devel@openvz.org, KAMEZAWA Hiroyuki , Tejun Heo , Pekka Enberg On Tue, 26 Jun 2012, Glauber Costa wrote: > > > @@ -416,6 +423,43 @@ static inline void sock_update_memcg(struct sock *sk) > > > static inline void sock_release_memcg(struct sock *sk) > > > { > > > } > > > + > > > +#define mem_cgroup_kmem_on 0 > > > +#define __mem_cgroup_new_kmem_page(a, b, c) false > > > +#define __mem_cgroup_free_kmem_page(a,b ) > > > +#define __mem_cgroup_commit_kmem_page(a, b, c) > > > +#define is_kmem_tracked_alloc (false) > > > #endif /* CONFIG_CGROUP_MEM_RES_CTLR_KMEM */ > > > + > > > +static __always_inline > > > +bool mem_cgroup_new_kmem_page(gfp_t gfp, void *handle, int order) > > > +{ > > > + if (!mem_cgroup_kmem_on) > > > + return true; > > > + if (!is_kmem_tracked_alloc) > > > + return true; > > > + if (!current->mm) > > > + return true; > > > + if (in_interrupt()) > > > + return true; > > > > You can't test for current->mm in irq context, so you need to check for > > in_interrupt() first. > > > Right, thanks. > > > Also, what prevents __mem_cgroup_new_kmem_page() > > from being called for a kthread that has called use_mm() before > > unuse_mm()? > > Nothing, but I also don't see how to prevent that. You can test for current->flags & PF_KTHREAD following the check for in_interrupt() and return true, it's what you were trying to do with the check for !current->mm. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org