lkml.org 
[lkml]   [2011]   [Mar]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v6 4/9] memcg: add kernel calls for memcg dirty page stats
On Fri, Mar 11, 2011 at 10:43:26AM -0800, Greg Thelen wrote:
> Add calls into memcg dirty page accounting. Notify memcg when pages
> transition between clean, file dirty, writeback, and unstable nfs.
> This allows the memory controller to maintain an accurate view of
> the amount of its memory that is dirty.
>
> Signed-off-by: Greg Thelen <gthelen@google.com>
> Signed-off-by: Andrea Righi <arighi@develer.com>
> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
> Reviewed-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
> ---
> Changelog since v5:
> - moved accounting site in test_clear_page_writeback() and
> test_set_page_writeback().
>
> fs/nfs/write.c | 4 ++++
> mm/filemap.c | 1 +
> mm/page-writeback.c | 10 ++++++++--
> mm/truncate.c | 1 +
> 4 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/fs/nfs/write.c b/fs/nfs/write.c
> index 42b92d7..7863777 100644
> --- a/fs/nfs/write.c
> +++ b/fs/nfs/write.c
> @@ -451,6 +451,7 @@ nfs_mark_request_commit(struct nfs_page *req)
> NFS_PAGE_TAG_COMMIT);
> nfsi->ncommit++;
> spin_unlock(&inode->i_lock);
> + mem_cgroup_inc_page_stat(req->wb_page, MEMCG_NR_FILE_UNSTABLE_NFS);
> inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
> inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_RECLAIMABLE);
> __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
> @@ -462,6 +463,7 @@ nfs_clear_request_commit(struct nfs_page *req)
> struct page *page = req->wb_page;
>
> if (test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) {
> + mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_UNSTABLE_NFS);
> dec_zone_page_state(page, NR_UNSTABLE_NFS);
> dec_bdi_stat(page->mapping->backing_dev_info, BDI_RECLAIMABLE);
> return 1;
> @@ -1319,6 +1321,8 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how)
> req = nfs_list_entry(head->next);
> nfs_list_remove_request(req);
> nfs_mark_request_commit(req);
> + mem_cgroup_dec_page_stat(req->wb_page,
> + MEMCG_NR_FILE_UNSTABLE_NFS);
> dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
> dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
> BDI_RECLAIMABLE);
> diff --git a/mm/filemap.c b/mm/filemap.c
> index a6cfecf..7e751fe 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -143,6 +143,7 @@ void __delete_from_page_cache(struct page *page)
> * having removed the page entirely.
> */
> if (PageDirty(page) && mapping_cap_account_dirty(mapping)) {
> + mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_DIRTY);
> dec_zone_page_state(page, NR_FILE_DIRTY);
> dec_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
> }
> diff --git a/mm/page-writeback.c b/mm/page-writeback.c
> index 632b464..d8005b0 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -1118,6 +1118,7 @@ int __set_page_dirty_no_writeback(struct page *page)
> void account_page_dirtied(struct page *page, struct address_space *mapping)
> {
> if (mapping_cap_account_dirty(mapping)) {
> + mem_cgroup_inc_page_stat(page, MEMCG_NR_FILE_DIRTY);
> __inc_zone_page_state(page, NR_FILE_DIRTY);
> __inc_zone_page_state(page, NR_DIRTIED);
> __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
> @@ -1317,6 +1318,7 @@ int clear_page_dirty_for_io(struct page *page)
> * for more comments.
> */
> if (TestClearPageDirty(page)) {
> + mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_DIRTY);
> dec_zone_page_state(page, NR_FILE_DIRTY);
> dec_bdi_stat(mapping->backing_dev_info,
> BDI_RECLAIMABLE);
> @@ -1352,8 +1354,10 @@ int test_clear_page_writeback(struct page *page)
> } else {
> ret = TestClearPageWriteback(page);
> }
> - if (ret)
> + if (ret) {
> + mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_WRITEBACK);
> dec_zone_page_state(page, NR_WRITEBACK);
> + }
> return ret;
> }
>
> @@ -1386,8 +1390,10 @@ int test_set_page_writeback(struct page *page)
> } else {
> ret = TestSetPageWriteback(page);
> }
> - if (!ret)
> + if (!ret) {
> + mem_cgroup_inc_page_stat(page, MEMCG_NR_FILE_WRITEBACK);
> account_page_writeback(page);
> + }
> return ret;
>
> }

At least in mainline, NR_WRITEBACK handling codes are following as.

1) increase

* account_page_writeback

2) decrease

* test_clear_page_writeback
* __nilfs_end_page_io

I think account_page_writeback name is good to add your account function into that.
The problem is decreasement. Normall we can handle decreasement in test_clear_page_writeback.
But I am not sure it's okay in __nilfs_end_page_io.
I think if __nilfs_end_page_io is right, __nilfs_end_page_io should call
mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_WRITEBACK).

What do you think about it?



--
Kind regards,
Minchan Kim


\
 
 \ /
  Last update: 2011-03-14 16:13    [W:2.637 / U:0.320 seconds]
©2003-2014 Jasper Spaans. hosted at Digital Ocean