| Message ID | 20160831114616.2053-1-wangxg.fnst@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On 08/31/2016 07:46 AM, Wang Xiaoguang wrote: > If can_overcommit() in btrfs_calc_reclaim_metadata_size() returns true, > btrfs_async_reclaim_metadata_space() will not reclaim metadata space, just > return directly and also forget to wake up process which are waiting for > their tickets, so these processes will wait endlessly. > > Fstests case generic/172 with mount option "-o compress=lzo" have revealed > this bug in my test machine. Here if we have tickets to handle, we must > handle them first. > > Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com> Yup good catch, you can add Reviewed-by: Josef Bacik <jbacik@fb.com> Thanks, Josef -- 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
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 0450dc4..8c8a4d1 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4901,11 +4901,6 @@ btrfs_calc_reclaim_metadata_size(struct btrfs_root *root, u64 expected; u64 to_reclaim = 0; - to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M); - if (can_overcommit(root, space_info, to_reclaim, - BTRFS_RESERVE_FLUSH_ALL)) - return 0; - list_for_each_entry(ticket, &space_info->tickets, list) to_reclaim += ticket->bytes; list_for_each_entry(ticket, &space_info->priority_tickets, list) @@ -4913,6 +4908,11 @@ btrfs_calc_reclaim_metadata_size(struct btrfs_root *root, if (to_reclaim) return to_reclaim; + to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M); + if (can_overcommit(root, space_info, to_reclaim, + BTRFS_RESERVE_FLUSH_ALL)) + return 0; + used = space_info->bytes_used + space_info->bytes_reserved + space_info->bytes_pinned + space_info->bytes_readonly + space_info->bytes_may_use;
If can_overcommit() in btrfs_calc_reclaim_metadata_size() returns true, btrfs_async_reclaim_metadata_space() will not reclaim metadata space, just return directly and also forget to wake up process which are waiting for their tickets, so these processes will wait endlessly. Fstests case generic/172 with mount option "-o compress=lzo" have revealed this bug in my test machine. Here if we have tickets to handle, we must handle them first. Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com> --- fs/btrfs/extent-tree.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)