From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lj1-f199.google.com (mail-lj1-f199.google.com [209.85.208.199]) by kanga.kvack.org (Postfix) with ESMTP id 4777E8E0038 for ; Wed, 9 Jan 2019 07:20:46 -0500 (EST) Received: by mail-lj1-f199.google.com with SMTP id f22-v6so1752695lja.7 for ; Wed, 09 Jan 2019 04:20:46 -0800 (PST) Received: from relay.sw.ru (relay.sw.ru. [185.231.240.75]) by mx.google.com with ESMTPS id u191-v6si73472439lja.171.2019.01.09.04.20.44 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Jan 2019 04:20:44 -0800 (PST) Subject: [PATCH 3/3] mm: Pass FGP_NOWAIT in generic_file_buffered_read and enable ext4 From: Kirill Tkhai Date: Wed, 09 Jan 2019 15:20:35 +0300 Message-ID: <154703643564.32690.8416317230641240199.stgit@localhost.localdomain> In-Reply-To: <154703479840.32690.6504699919905946726.stgit@localhost.localdomain> References: <154703479840.32690.6504699919905946726.stgit@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, hannes@cmpxchg.org, josef@toxicpanda.com, jack@suse.cz, hughd@google.com, ktkhai@virtuozzo.com, darrick.wong@oracle.com, mhocko@suse.com, aryabinin@virtuozzo.com, guro@fb.com, mgorman@techsingularity.net, shakeelb@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org All page-obtaining functions, which are used by ext4, look to go thru pagecache_get_page() path, so all taken uncharged pages will be properly charged. Thus, we enable AS_KEEP_MEMCG_RECLAIM for ext4 regular files. Since memcg accounting requires page lock, and function generic_file_buffered_read() is the only of ext4-used functions, which does not care about FGP_NOWAIT, we make it use find_get_page_flags() and pass the flag. This allows pagecache_get_page() to use lock_page(), when it's possible. Signed-off-by: Kirill Tkhai --- fs/ext4/inode.c | 1 + mm/filemap.c | 8 +++++++- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b1d7ddd70eee..2fc9e4a7c0db 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5065,6 +5065,7 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino, inode->i_op = &ext4_file_inode_operations; inode->i_fop = &ext4_file_operations; ext4_set_aops(inode); + set_bit(AS_KEEP_MEMCG_RECLAIM, &inode->i_mapping->flags); } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &ext4_dir_inode_operations; inode->i_fop = &ext4_dir_operations; diff --git a/mm/filemap.c b/mm/filemap.c index 2603c44fc74a..46922003811f 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2061,6 +2061,11 @@ static void shrink_readahead_size_eio(struct file *filp, ra->ra_pages /= 4; } +static int kiocb_fgp_flags(struct kiocb *iocb) +{ + return (iocb->ki_flags & IOCB_NOWAIT) ? FGP_NOWAIT : 0; +} + /** * generic_file_buffered_read - generic file read routine * @iocb: the iocb to read @@ -2111,7 +2116,8 @@ static ssize_t generic_file_buffered_read(struct kiocb *iocb, goto out; } - page = find_get_page(mapping, index); + page = find_get_page_flags(mapping, index, + kiocb_fgp_flags(iocb)); if (!page) { if (iocb->ki_flags & IOCB_NOWAIT) goto would_block;