From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1050.oracle.com ([156.151.31.82]:42897 "EHLO userp1050.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751113AbdCGV6B (ORCPT ); Tue, 7 Mar 2017 16:58:01 -0500 Received: from userp1040.oracle.com (userp1040.oracle.com [156.151.31.81]) by userp1050.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id v27KbAVA016569 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Tue, 7 Mar 2017 20:37:10 GMT Date: Tue, 7 Mar 2017 12:34:07 -0800 From: Liu Bo To: Adam Borowski Cc: Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org Subject: Re: [PATCH] btrfs: fix a bogus warning when converting only data or metadata Message-ID: <20170307203406.GC12408@lim.localdomain> Reply-To: bo.li.liu@oracle.com References: <20170307054251.4361-1-kilobyte@angband.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20170307054251.4361-1-kilobyte@angband.pl> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Tue, Mar 07, 2017 at 06:42:51AM +0100, Adam Borowski wrote: > If your filesystem has, eg, data:raid0 metadata:raid1, and you run "btrfs > balance -dconvert=raid1", the meta.target field will be uninitialized. > That's otherwise ok, as it's unused except for this warning. > > Thus, let's use the existing set of raid levels for the comparison. > > As a side effect, non-convert balances will now nag about data>metadata. > > Signed-off-by: Adam Borowski > --- > To reproduce: > dd if=/dev/zero bs=1048576 count=1 seek=4095 of=ra > dd if=/dev/zero bs=1048576 count=1 seek=4095 of=rb > mkfs.btrfs ra rb # defaults to -draid0 -mraid1 > losetup -f ra > losetup -f rb > mount /dev/loop0 /mnt/vol1 > btrfs balance start -dconvert=raid1 /mnt/vol1 > > fs/btrfs/volumes.c | 5 +++++ > 1 file changed, 5 insertions(+) > diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c > index 3645af2749f8..c016db81ba43 100644 > --- a/fs/btrfs/volumes.c > +++ b/fs/btrfs/volumes.c > @@ -3846,6 +3846,11 @@ int btrfs_balance(struct btrfs_balance_control *bctl, > } > } while (read_seqretry(&fs_info->profiles_lock, seq)); > > + /* if we're not converting, the target field is uninitialized */ > + if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) > + bctl->meta.target = fs_info->avail_metadata_alloc_bits; > + if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) > + bctl->data.target = fs_info->avail_data_alloc_bits; This looks good, but this also brings another side effect, @bctl would also be kept in balance_item which will be used to resume balance in case of crash, so it may see a different bctl->meta.target. So would you please use local varibles for meta.target and data.target? Thanks, -liubo > if (btrfs_get_num_tolerated_disk_barrier_failures(bctl->meta.target) < > btrfs_get_num_tolerated_disk_barrier_failures(bctl->data.target)) { > btrfs_warn(fs_info, > -- > 2.11.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html