From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754410AbZBJEkR (ORCPT ); Mon, 9 Feb 2009 23:40:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752017AbZBJEkD (ORCPT ); Mon, 9 Feb 2009 23:40:03 -0500 Received: from ns2.suse.de ([195.135.220.15]:34981 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751266AbZBJEkA (ORCPT ); Mon, 9 Feb 2009 23:40:00 -0500 Date: Tue, 10 Feb 2009 05:39:53 +0100 From: Nick Piggin To: Linux Kernel Mailing List , Peter Zijlstra , YAMAMOTO Takashi , Andrew Morton Subject: [patch] mm: task dirty accounting fix Message-ID: <20090210043953.GD28301@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, This is based from an earlier patch from YAMAMOTO-san which I have somewhat simplified. What do you think? Thanks, Nick -- YAMAMOTO-san noticed that task_dirty_inc doesn't seem to be called properly for cases where set_page_dirty is not used to dirty a page (eg. mark_buffer_dirty). Additionally, there is some inconsistency about when task_dirty_inc is called. It is used for dirty balancing, however it even gets called for __set_page_dirty_no_writeback. So rather than increment it in a set_page_dirty wrapper, move it down to exactly where the dirty page accounting stats are incremented. Cc: YAMAMOTO Takashi Signed-off-by: Nick Piggin --- fs/buffer.c | 1 + include/linux/mm.h | 1 + mm/page-writeback.c | 13 +++---------- 3 files changed, 5 insertions(+), 10 deletions(-) Index: linux-2.6/include/linux/mm.h =================================================================== --- linux-2.6.orig/include/linux/mm.h +++ linux-2.6/include/linux/mm.h @@ -1162,6 +1162,7 @@ extern int filemap_fault(struct vm_area_ /* mm/page-writeback.c */ int write_one_page(struct page *page, int wait); +void task_dirty_inc(struct task_struct *tsk); /* readahead.c */ #define VM_MAX_READAHEAD 128 /* kbytes */ Index: linux-2.6/mm/page-writeback.c =================================================================== --- linux-2.6.orig/mm/page-writeback.c +++ linux-2.6/mm/page-writeback.c @@ -241,7 +241,7 @@ void bdi_writeout_inc(struct backing_dev } EXPORT_SYMBOL_GPL(bdi_writeout_inc); -static inline void task_dirty_inc(struct task_struct *tsk) +void task_dirty_inc(struct task_struct *tsk) { prop_inc_single(&vm_dirties, &tsk->dirties); } @@ -1228,6 +1228,7 @@ int __set_page_dirty_nobuffers(struct pa __inc_zone_page_state(page, NR_FILE_DIRTY); __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE); + task_dirty_inc(current); task_io_account_write(PAGE_CACHE_SIZE); } radix_tree_tag_set(&mapping->page_tree, @@ -1263,7 +1264,7 @@ EXPORT_SYMBOL(redirty_page_for_writepage * If the mapping doesn't provide a set_page_dirty a_op, then * just fall through and assume that it wants buffer_heads. */ -static int __set_page_dirty(struct page *page) +int set_page_dirty(struct page *page) { struct address_space *mapping = page_mapping(page); @@ -1281,14 +1282,6 @@ static int __set_page_dirty(struct page } return 0; } - -int set_page_dirty(struct page *page) -{ - int ret = __set_page_dirty(page); - if (ret) - task_dirty_inc(current); - return ret; -} EXPORT_SYMBOL(set_page_dirty); /* Index: linux-2.6/fs/buffer.c =================================================================== --- linux-2.6.orig/fs/buffer.c +++ linux-2.6/fs/buffer.c @@ -628,6 +628,7 @@ static int __set_page_dirty(struct page __inc_zone_page_state(page, NR_FILE_DIRTY); __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE); + task_dirty_inc(current); task_io_account_write(PAGE_CACHE_SIZE); } radix_tree_tag_set(&mapping->page_tree,