From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx136.postini.com [74.125.245.136]) by kanga.kvack.org (Postfix) with SMTP id 9A1996B004A for ; Tue, 28 Feb 2012 19:33:08 -0500 (EST) Date: Wed, 29 Feb 2012 08:27:43 +0800 From: Fengguang Wu Subject: Re: [PATCH 2/9] memcg: add dirty page accounting infrastructure Message-ID: <20120229002743.GA11583@localhost> References: <20120228140022.614718843@intel.com> <20120228144746.971869014@intel.com> <20120228143738.b84d49ff.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120228143738.b84d49ff.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Greg Thelen , Jan Kara , Ying Han , "hannes@cmpxchg.org" , KAMEZAWA Hiroyuki , Rik van Riel , Andrea Righi , Linux Memory Management List , LKML On Tue, Feb 28, 2012 at 02:37:38PM -0800, Andrew Morton wrote: > On Tue, 28 Feb 2012 22:00:24 +0800 > Fengguang Wu wrote: > > > From: Greg Thelen > > > > Add memcg routines to count dirty, writeback, and unstable_NFS pages. > > These routines are not yet used by the kernel to count such pages. A > > later change adds kernel calls to these new routines. > > > > As inode pages are marked dirty, if the dirtied page's cgroup differs > > from the inode's cgroup, then mark the inode shared across several > > cgroup. > > > > ... > > > > @@ -1885,6 +1888,44 @@ void mem_cgroup_update_page_stat(struct > > ClearPageCgroupFileMapped(pc); > > idx = MEM_CGROUP_STAT_FILE_MAPPED; > > break; > > + > > + case MEMCG_NR_FILE_DIRTY: > > + /* Use Test{Set,Clear} to only un/charge the memcg once. */ > > + if (val > 0) { > > + if (TestSetPageCgroupFileDirty(pc)) > > + val = 0; > > + } else { > > + if (!TestClearPageCgroupFileDirty(pc)) > > + val = 0; > > + } > > Made me scratch my head for a while, but I see now that the `val' arg > to (the undocumented) mem_cgroup_update_page_stat() can only ever have > the values 1 or -1. I hope. Yeah, I see it's called this way: 3 151 /c/linux/include/linux/memcontrol.h <> mem_cgroup_update_page_stat(page, idx, 1); 4 157 /c/linux/include/linux/memcontrol.h <> mem_cgroup_update_page_stat(page, idx, -1); Thanks, Fengguang -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org