From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754797AbYF2ANW (ORCPT ); Sat, 28 Jun 2008 20:13:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751873AbYF2ANN (ORCPT ); Sat, 28 Jun 2008 20:13:13 -0400 Received: from extu-mxob-2.symantec.com ([216.10.194.135]:36071 "EHLO extu-mxob-2.symantec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751769AbYF2ANM (ORCPT ); Sat, 28 Jun 2008 20:13:12 -0400 Date: Sun, 29 Jun 2008 01:13:20 +0100 (BST) From: Hugh Dickins X-X-Sender: hugh@blonde.site To: Andrew Morton cc: KAMEZAWA Hiroyuki , Balbir Singh , linux-kernel@vger.kernel.org Subject: [PATCH] memcg: fix shmem_unuse_inode charging Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The mem_cgroup_cache_charge in shmem_unuse_inode has been moved after the radix_tree_preload, so generating a BUG: sleeping function called from invalid context. Move it back, uncharging where necessary. Signed-off-by: Hugh Dickins --- Should follow mmotm's memcg-remove-refcnt-from-page_cgroup.patch mm/shmem.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) --- mmotm/mm/shmem.c 2008-06-27 13:39:20.000000000 +0100 +++ linux/mm/shmem.c 2008-06-27 17:25:41.000000000 +0100 @@ -922,27 +922,24 @@ found: error = 1; if (!inode) goto out; - error = radix_tree_preload(GFP_KERNEL); - if (error) - goto out; - /* - * Because we use GFP_NOWAIT in add_to_page_cache(), we can see -ENOMEM - * failure because of memory pressure in memory resource controller. - * Then, precharge page while we can wait, uncharge at failure will be - * automatically done in add_to_page_cache() - */ + /* Precharge page using GFP_KERNEL while we can wait */ error = mem_cgroup_cache_charge(page, current->mm, GFP_KERNEL); if (error) - goto preload_out; - + goto out; + error = radix_tree_preload(GFP_KERNEL); + if (error) { + mem_cgroup_uncharge_cache_page(page); + goto out; + } error = 1; spin_lock(&info->lock); ptr = shmem_swp_entry(info, idx, NULL); - if (ptr && ptr->val == entry.val) - error = add_to_page_cache(page, inode->i_mapping, idx, - GFP_NOWAIT); - else /* we don't have to account this page. */ + if (ptr && ptr->val == entry.val) { + error = add_to_page_cache(page, inode->i_mapping, + idx, GFP_NOWAIT); + /* does mem_cgroup_uncharge_cache_page on error */ + } else /* we must compensate for our precharge above */ mem_cgroup_uncharge_cache_page(page); if (error == -EEXIST) { @@ -969,7 +966,6 @@ found: if (ptr) shmem_swp_unmap(ptr); spin_unlock(&info->lock); -preload_out: radix_tree_preload_end(); out: unlock_page(page);