From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:60522 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727191AbeHaLh6 (ORCPT ); Fri, 31 Aug 2018 07:37:58 -0400 Subject: Re: [PATCH 22/35] btrfs: make sure we create all new bgs To: Josef Bacik , linux-btrfs@vger.kernel.org References: <20180830174225.2200-1-josef@toxicpanda.com> <20180830174225.2200-23-josef@toxicpanda.com> From: Nikolay Borisov Message-ID: Date: Fri, 31 Aug 2018 10:31:49 +0300 MIME-Version: 1.0 In-Reply-To: <20180830174225.2200-23-josef@toxicpanda.com> Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 30.08.2018 20:42, Josef Bacik wrote: > We can actually allocate new chunks while we're creating our bg's, so > instead of doing list_for_each_safe, just do while (!list_empty()) so we > make sure to catch any new bg's that get added to the list. HOw can this occur, please elaborate and put an example callstack in the commit log. > > Signed-off-by: Josef Bacik > --- > fs/btrfs/extent-tree.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index ca98c39308f6..fc30ff96f0d6 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -10331,7 +10331,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info) > void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans) > { > struct btrfs_fs_info *fs_info = trans->fs_info; > - struct btrfs_block_group_cache *block_group, *tmp; > + struct btrfs_block_group_cache *block_group; > struct btrfs_root *extent_root = fs_info->extent_root; > struct btrfs_block_group_item item; > struct btrfs_key key; > @@ -10339,7 +10339,10 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans) > bool can_flush_pending_bgs = trans->can_flush_pending_bgs; > > trans->can_flush_pending_bgs = false; > - list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) { > + while (!list_empty(&trans->new_bgs)) { > + block_group = list_first_entry(&trans->new_bgs, > + struct btrfs_block_group_cache, > + bg_list); > if (ret) > goto next; > >