From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934229Ab2JKB32 (ORCPT ); Wed, 10 Oct 2012 21:29:28 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:60353 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934029Ab2JKBY2 (ORCPT ); Wed, 10 Oct 2012 21:24:28 -0400 X-Sasl-enc: kwN0xQr482KS2NUL/AE7dhMwVailMmPLpFWpXcOXmP7O 1349918667 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Yongqiang Yang , "Theodore Tso" Subject: [ 066/120] ext4: avoid duplicate writes of the backup bg descriptor blocks Date: Thu, 11 Oct 2012 10:00:18 +0900 Message-Id: <20121011005838.135913092@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.rc0.18.gf84667d In-Reply-To: <20121011005825.364610894@linuxfoundation.org> References: <20121011005825.364610894@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yongqiang Yang commit 2ebd1704ded88a8ae29b5f3998b13959c715c4be upstream. The resize code was needlessly writing the backup block group descriptor blocks multiple times (once per block group) during an online resize. Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- fs/ext4/resize.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1302,13 +1302,15 @@ exit_journal: err = err2; if (!err) { - int i; + int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); + int gdb_num_end = ((group + flex_gd->count - 1) / + EXT4_DESC_PER_BLOCK(sb)); + update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, sizeof(struct ext4_super_block)); - for (i = 0; i < flex_gd->count; i++, group++) { + for (; gdb_num <= gdb_num_end; gdb_num++) { struct buffer_head *gdb_bh; - int gdb_num; - gdb_num = group / EXT4_BLOCKS_PER_GROUP(sb); + gdb_bh = sbi->s_group_desc[gdb_num]; update_backups(sb, gdb_bh->b_blocknr, gdb_bh->b_data, gdb_bh->b_size);