Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757554Ab2B2CDI (ORCPT ); Tue, 28 Feb 2012 21:03:08 -0500 Received: from zene.cmpxchg.org ([85.214.230.12]:46279 "EHLO zene.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752773Ab2B2CDG (ORCPT ); Tue, 28 Feb 2012 21:03:06 -0500 Date: Wed, 29 Feb 2012 03:02:46 +0100 From: Johannes Weiner To: KAMEZAWA Hiroyuki Cc: Konstantin Khlebnikov , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch 2/2] mm: memcg: count pte references from every member of the reclaimed hierarchy Message-ID: <20120229020246.GF1702@cmpxchg.org> References: <1330438489-21909-1-git-send-email-hannes@cmpxchg.org> <1330438489-21909-2-git-send-email-hannes@cmpxchg.org> <20120229093946.611a20d3.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120229093946.611a20d3.kamezawa.hiroyu@jp.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1321 Lines: 35 On Wed, Feb 29, 2012 at 09:39:46AM +0900, KAMEZAWA Hiroyuki wrote: > On Tue, 28 Feb 2012 15:14:49 +0100 > Johannes Weiner wrote: > > --- a/mm/vmscan.c > > +++ b/mm/vmscan.c > > @@ -708,7 +708,8 @@ static enum page_references page_check_references(struct page *page, > > int referenced_ptes, referenced_page; > > unsigned long vm_flags; > > > > - referenced_ptes = page_referenced(page, 1, mz->mem_cgroup, &vm_flags); > > + referenced_ptes = page_referenced(page, 1, sc->target_mem_cgroup, > > + &vm_flags); > > > I'm sorry if I don't understand the codes... !sc->target_mem_cgroup case is handled ? Yes, but it's not obvious from the diff alone. page_referenced() does this: /* * If we are reclaiming on behalf of a cgroup, skip * counting on behalf of references from different * cgroups */ if (memcg && !mm_match_cgroup(vma->vm_mm, memcg)) continue; As a result, !sc->target_mem_cgroup -- global reclaim -- will never ignore references, or put differently, respect references from all memcgs, which is what we want. -- 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/