From: Theodore Ts'o Subject: [PATCH 1/3] block_write_full_page: Use synchronous writes for WBC_SYNC_ALL writebacks Date: Fri, 27 Mar 2009 16:24:29 -0400 Message-ID: <1238185471-31152-2-git-send-email-tytso@mit.edu> References: <1238185471-31152-1-git-send-email-tytso@mit.edu> Cc: Ext4 Developers List , jack@suse.cz, Theodore Ts'o To: Linux Kernel Developers List Return-path: Received: from THUNK.ORG ([69.25.196.29]:45714 "EHLO thunker.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761547AbZC0UYf (ORCPT ); Fri, 27 Mar 2009 16:24:35 -0400 In-Reply-To: <1238185471-31152-1-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: When doing synchronous writes because wbc->sync_mode is set to WBC_SYNC_ALL, send the write request using WRITE_SYNC, so that we don't unduly block system calls such as fsync(). Signed-off-by: "Theodore Ts'o" --- fs/buffer.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 891e1c7..e7ebd95 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1714,6 +1714,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page, struct buffer_head *bh, *head; const unsigned blocksize = 1 << inode->i_blkbits; int nr_underway = 0; + int write_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); BUG_ON(!PageLocked(page)); @@ -1805,7 +1806,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page, do { struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { - submit_bh(WRITE, bh); + submit_bh(write_op, bh); nr_underway++; } bh = next; @@ -1859,7 +1860,7 @@ recover: struct buffer_head *next = bh->b_this_page; if (buffer_async_write(bh)) { clear_buffer_dirty(bh); - submit_bh(WRITE, bh); + submit_bh(write_op, bh); nr_underway++; } bh = next; -- 1.5.6.3