Re: [PATCH v5 6/9] memcg: add kernel calls for memcg dirty pagestats

From: Minchan Kim
Date: Sun Feb 27 2011 - 12:02:01 EST


On Fri, Feb 25, 2011 at 01:35:57PM -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@xxxxxxxxxx>
> Signed-off-by: Andrea Righi <arighi@xxxxxxxxxxx>
> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
> Reviewed-by: Daisuke Nishimura <nishimura@xxxxxxxxxxxxxxxxx>
> ---
> fs/nfs/write.c | 4 ++++
> mm/filemap.c | 1 +
> mm/page-writeback.c | 4 ++++
> mm/truncate.c | 1 +
> 4 files changed, 10 insertions(+), 0 deletions(-)
>
> diff --git a/fs/nfs/write.c b/fs/nfs/write.c
> index c8278f4..118935b 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;
> @@ -1317,6 +1319,8 @@ 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 7b137b4..e234b8d 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 00424b9..8d61cfa 100644
> --- a/mm/page-writeback.c
> +++ b/mm/page-writeback.c
> @@ -1119,6 +1119,7 @@ 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);
> @@ -1308,6 +1309,7 @@ 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);
> @@ -1338,6 +1340,7 @@ int test_clear_page_writeback(struct page *page)
> __dec_bdi_stat(bdi, BDI_WRITEBACK);
> __bdi_writeout_inc(bdi);
> }
> + mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_WRITEBACK);
> }
> spin_unlock_irqrestore(&mapping->tree_lock, flags);
> } else {
> @@ -1365,6 +1368,7 @@ int test_set_page_writeback(struct page *page)
> PAGECACHE_TAG_WRITEBACK);
> if (bdi_cap_account_writeback(bdi))
> __inc_bdi_stat(bdi, BDI_WRITEBACK);
> + mem_cgroup_inc_page_stat(page, MEMCG_NR_FILE_WRITEBACK);

Question:
Why should we care of BDI_CAP_NO_WRITEBACK?


--
Kind regards,
Minchan Kim
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/