Messages in this thread | | | Date | Wed, 29 Feb 2012 08:27:43 +0800 | From | Fengguang Wu <> | Subject | Re: [PATCH 2/9] memcg: add dirty page accounting infrastructure |
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On Tue, Feb 28, 2012 at 02:37:38PM -0800, Andrew Morton wrote: > On Tue, 28 Feb 2012 22:00:24 +0800 > Fengguang Wu <fengguang.wu@intel.com> wrote: > > > From: Greg Thelen <gthelen@google.com> > > > > 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_inc_page_stat>> mem_cgroup_update_page_stat(page, idx, 1);
4 157 /c/linux/include/linux/memcontrol.h <<mem_cgroup_dec_page_stat>> mem_cgroup_update_page_stat(page, idx, -1);
Thanks, Fengguang
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