From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:49711 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752004Ab2L0JDz (ORCPT ); Thu, 27 Dec 2012 04:03:55 -0500 Received: from acsinet22.oracle.com (acsinet22.oracle.com [141.146.126.238]) by aserp1040.oracle.com (Sentrion-MTA-4.2.2/Sentrion-MTA-4.2.2) with ESMTP id qBR93rur008507 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 27 Dec 2012 09:03:54 GMT Received: from acsmt358.oracle.com (acsmt358.oracle.com [141.146.40.158]) by acsinet22.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id qBR93rWI009268 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Thu, 27 Dec 2012 09:03:53 GMT Received: from abhmt114.oracle.com (abhmt114.oracle.com [141.146.116.66]) by acsmt358.oracle.com (8.12.11.20060308/8.12.11) with ESMTP id qBR93rEE019842 for ; Thu, 27 Dec 2012 03:03:53 -0600 From: Liu Bo To: linux-btrfs@vger.kernel.org Subject: [PATCH 6/8] Btrfs: save us a read_lock Date: Thu, 27 Dec 2012 17:01:22 +0800 Message-Id: <1356598884-22952-6-git-send-email-bo.li.liu@oracle.com> In-Reply-To: <1356598884-22952-1-git-send-email-bo.li.liu@oracle.com> References: <1356598884-22952-1-git-send-email-bo.li.liu@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: This does not change the logic of code, but can save us a read_lock. Signed-off-by: Liu Bo --- fs/btrfs/locking.c | 5 ++--- 1 files changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index 2a1762c..e95df43 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -113,11 +113,10 @@ again: read_unlock(&eb->lock); return; } - read_unlock(&eb->lock); - wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0); - read_lock(&eb->lock); if (atomic_read(&eb->blocking_writers)) { read_unlock(&eb->lock); + wait_event(eb->write_lock_wq, + atomic_read(&eb->blocking_writers) == 0); goto again; } atomic_inc(&eb->read_locks); -- 1.7.7.6