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 <redacted>
Signed-off-by: Andrea Righi <redacted>
Acked-by: KAMEZAWA Hiroyuki <redacted>
Reviewed-by: Daisuke Nishimura <redacted>
---
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;
 
 }