[Devel] Re: [PATCH 05/10] memcg: add dirty page accounting infrastructure
Greg Thelen
gthelen at google.com
Tue Oct 5 00:35:07 PDT 2010
KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com> writes:
> On Sun, 3 Oct 2010 23:58:00 -0700
> Greg Thelen <gthelen at google.com> wrote:
>
>> Add memcg routines to track 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.
>>
>> Signed-off-by: Greg Thelen <gthelen at google.com>
>> Signed-off-by: Andrea Righi <arighi at develer.com>
>
> a small request. see below.
>
>> ---
>> include/linux/memcontrol.h | 3 +
>> mm/memcontrol.c | 89 ++++++++++++++++++++++++++++++++++++++++----
>> 2 files changed, 84 insertions(+), 8 deletions(-)
>>
>> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
>> index 7c7bec4..6303da1 100644
>> --- a/include/linux/memcontrol.h
>> +++ b/include/linux/memcontrol.h
>> @@ -28,6 +28,9 @@ struct mm_struct;
>> /* Stats that can be updated by kernel. */
>> enum mem_cgroup_write_page_stat_item {
>> MEMCG_NR_FILE_MAPPED, /* # of pages charged as file rss */
>> + MEMCG_NR_FILE_DIRTY, /* # of dirty pages in page cache */
>> + MEMCG_NR_FILE_WRITEBACK, /* # of pages under writeback */
>> + MEMCG_NR_FILE_UNSTABLE_NFS, /* # of NFS unstable pages */
>> };
>>
>> extern unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan,
>> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
>> index 267d774..f40839f 100644
>> --- a/mm/memcontrol.c
>> +++ b/mm/memcontrol.c
>> @@ -85,10 +85,13 @@ enum mem_cgroup_stat_index {
>> */
>> MEM_CGROUP_STAT_CACHE, /* # of pages charged as cache */
>> MEM_CGROUP_STAT_RSS, /* # of pages charged as anon rss */
>> - MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */
>> MEM_CGROUP_STAT_PGPGIN_COUNT, /* # of pages paged in */
>> MEM_CGROUP_STAT_PGPGOUT_COUNT, /* # of pages paged out */
>> MEM_CGROUP_STAT_SWAPOUT, /* # of pages, swapped out */
>> + MEM_CGROUP_STAT_FILE_MAPPED, /* # of pages charged as file rss */
>> + MEM_CGROUP_STAT_FILE_DIRTY, /* # of dirty pages in page cache */
>> + MEM_CGROUP_STAT_FILE_WRITEBACK, /* # of pages under writeback */
>> + MEM_CGROUP_STAT_FILE_UNSTABLE_NFS, /* # of NFS unstable pages */
>> MEM_CGROUP_STAT_DATA, /* end of data requires synchronization */
>> /* incremented at every pagein/pageout */
>> MEM_CGROUP_EVENTS = MEM_CGROUP_STAT_DATA,
>> @@ -1626,6 +1629,48 @@ void mem_cgroup_update_page_stat(struct page *page,
>> 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))
>> + /* already set */
>> + val = 0;
>> + } else {
>> + if (!TestClearPageCgroupFileDirty(pc))
>> + /* already cleared */
>> + val = 0;
>> + }
>> + idx = MEM_CGROUP_STAT_FILE_DIRTY;
>> + break;
>> +
>> + case MEMCG_NR_FILE_WRITEBACK:
>> + /*
>> + * This counter is adjusted while holding the mapping's
>> + * tree_lock. Therefore there is no race between settings and
>> + * clearing of this flag.
>> + */
>
> nice description.
>
>> + if (val > 0)
>> + SetPageCgroupFileWriteback(pc);
>> + else
>> + ClearPageCgroupFileWriteback(pc);
>> + idx = MEM_CGROUP_STAT_FILE_WRITEBACK;
>> + break;
>> +
>> + case MEMCG_NR_FILE_UNSTABLE_NFS:
>> + /* Use Test{Set,Clear} to only un/charge the memcg once. */
>> + if (val > 0) {
>> + if (TestSetPageCgroupFileUnstableNFS(pc))
>> + /* already set */
>> + val = 0;
>> + } else {
>> + if (!TestClearPageCgroupFileUnstableNFS(pc))
>> + /* already cleared */
>> + val = 0;
>> + }
>> + idx = MEM_CGROUP_STAT_FILE_UNSTABLE_NFS;
>> + break;
>> +
>> default:
>> BUG();
>> }
>> @@ -2133,6 +2178,16 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *mem,
>> memcg_check_events(mem, pc->page);
>> }
>>
>> +static void mem_cgroup_move_account_page_stat(struct mem_cgroup *from,
>> + struct mem_cgroup *to,
>> + enum mem_cgroup_stat_index idx)
>> +{
>> + preempt_disable();
>> + __this_cpu_dec(from->stat->count[idx]);
>> + __this_cpu_inc(to->stat->count[idx]);
>> + preempt_enable();
>> +}
>> +
>> /**
>> * __mem_cgroup_move_account - move account of the page
>> * @pc: page_cgroup of the page.
>> @@ -2159,13 +2214,18 @@ static void __mem_cgroup_move_account(struct page_cgroup *pc,
>> VM_BUG_ON(!PageCgroupUsed(pc));
>> VM_BUG_ON(pc->mem_cgroup != from);
>>
>> - if (PageCgroupFileMapped(pc)) {
>> - /* Update mapped_file data for mem_cgroup */
>> - preempt_disable();
>> - __this_cpu_dec(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
>> - __this_cpu_inc(to->stat->count[MEM_CGROUP_STAT_FILE_MAPPED]);
>> - preempt_enable();
>> - }
>> + if (PageCgroupFileMapped(pc))
>> + mem_cgroup_move_account_page_stat(from, to,
>> + MEM_CGROUP_STAT_FILE_MAPPED);
>> + if (PageCgroupFileDirty(pc))
>> + mem_cgroup_move_account_page_stat(from, to,
>> + MEM_CGROUP_STAT_FILE_DIRTY);
>> + if (PageCgroupFileWriteback(pc))
>> + mem_cgroup_move_account_page_stat(from, to,
>> + MEM_CGROUP_STAT_FILE_WRITEBACK);
>> + if (PageCgroupFileUnstableNFS(pc))
>> + mem_cgroup_move_account_page_stat(from, to,
>> + MEM_CGROUP_STAT_FILE_UNSTABLE_NFS);
>> mem_cgroup_charge_statistics(from, pc, false);
>> if (uncharge)
>> /* This is not "cancel", but cancel_charge does all we need. */
>> @@ -3545,6 +3605,9 @@ enum {
>> MCS_PGPGIN,
>> MCS_PGPGOUT,
>> MCS_SWAP,
>> + MCS_FILE_DIRTY,
>> + MCS_WRITEBACK,
>> + MCS_UNSTABLE_NFS,
>> MCS_INACTIVE_ANON,
>> MCS_ACTIVE_ANON,
>> MCS_INACTIVE_FILE,
>> @@ -3567,6 +3630,9 @@ struct {
>> {"pgpgin", "total_pgpgin"},
>> {"pgpgout", "total_pgpgout"},
>> {"swap", "total_swap"},
>> + {"dirty", "total_dirty"},
>> + {"writeback", "total_writeback"},
>> + {"nfs", "total_nfs"},
>
> Could you make this as nfs_unstable as meminfo shows ?
> If I am a user, I think this is the number of NFS pages not NFS_UNSTABLE pages.
Good catch! In the next revision I will change this from
"nfs"/"total_nfs" to "NFS_Unstable"/"total_NFS_Unstable" to match
/proc/meminfo.
> Thanks,
> -Kame
_______________________________________________
Containers mailing list
Containers at lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/containers
More information about the Devel
mailing list