From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp2120.oracle.com ([141.146.126.78]:34516 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750955AbeAVFuS (ORCPT ); Mon, 22 Jan 2018 00:50:18 -0500 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w0M5nvos025927 for ; Mon, 22 Jan 2018 05:50:18 GMT Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp2120.oracle.com with ESMTP id 2fna5e0030-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Mon, 22 Jan 2018 05:50:18 +0000 Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w0M5oH6v030731 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Mon, 22 Jan 2018 05:50:17 GMT Received: from abhmp0005.oracle.com (abhmp0005.oracle.com [141.146.116.11]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w0M5oGJ6029145 for ; Mon, 22 Jan 2018 05:50:16 GMT From: Anand Jain To: linux-btrfs@vger.kernel.org Subject: [PATCH v2 2/2] btrfs: optimize move uuid_mutex closer to the critical section Date: Mon, 22 Jan 2018 13:51:23 +0800 Message-Id: <20180122055123.10404-2-anand.jain@oracle.com> In-Reply-To: <20180122055123.10404-1-anand.jain@oracle.com> References: <20180122055123.10404-1-anand.jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: Move uuid_mutex closer to the exclusion section. Signed-off-by: Anand Jain Reviewed-by: David Sterba --- v1->v1: No change. Add received reviewed-by. Thxs. fs/btrfs/volumes.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 001894782d84..d9166737c747 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1197,13 +1197,10 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, */ bytenr = btrfs_sb_offset(0); flags |= FMODE_EXCL; - mutex_lock(&uuid_mutex); bdev = blkdev_get_by_path(path, flags, holder); - if (IS_ERR(bdev)) { - ret = PTR_ERR(bdev); - goto error; - } + if (IS_ERR(bdev)) + return PTR_ERR(bdev); if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super)) { ret = -EINVAL; @@ -1214,7 +1211,12 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, transid = btrfs_super_generation(disk_super); total_devices = btrfs_super_num_devices(disk_super); + mutex_lock(&uuid_mutex); ret = device_list_add(path, disk_super, devid, fs_devices_ret); + if (ret >= 0 && fs_devices_ret) + (*fs_devices_ret)->total_devices = total_devices; + mutex_unlock(&uuid_mutex); + if (ret > 0) { if (disk_super->label[0]) pr_info("BTRFS: device label %s ", disk_super->label); @@ -1224,15 +1226,12 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, pr_cont("devid %llu transid %llu %s\n", devid, transid, path); ret = 0; } - if (!ret && fs_devices_ret) - (*fs_devices_ret)->total_devices = total_devices; btrfs_release_disk_super(page); error_bdev_put: blkdev_put(bdev, flags); -error: - mutex_unlock(&uuid_mutex); + return ret; } -- 2.15.0