From: Jan Kara Subject: Re: [PATCH 1/3] block_write_full_page: Use synchronous writes for WBC_SYNC_ALL writebacks Date: Fri, 27 Mar 2009 21:55:41 +0100 Message-ID: <20090327205541.GD31071@duck.suse.cz> References: <1238185471-31152-1-git-send-email-tytso@mit.edu> <1238185471-31152-2-git-send-email-tytso@mit.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linux Kernel Developers List , Ext4 Developers List , jack@suse.cz To: Theodore Ts'o Return-path: Received: from cantor2.suse.de ([195.135.220.15]:57099 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756213AbZC0Uzo (ORCPT ); Fri, 27 Mar 2009 16:55:44 -0400 Content-Disposition: inline In-Reply-To: <1238185471-31152-2-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Fri 27-03-09 16:24:29, Theodore Ts'o wrote: > 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" Looks sane. You can add "Acked-by: Jan Kara " Honza > --- > 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 > -- Jan Kara SUSE Labs, CR