From: Anand Jain anand.jain@oracle.com
[ Upstream commit a69976bc69308aa475d0ba3b8b3efd1d013c0460 ]
We had a report indicating that some read errors aren't reported by the device stats in the userland. It is important to have the errors reported in the device stat as user land scripts might depend on it to take the reasonable corrective actions. But to debug these issue we need to be really sure that request to reset the device stat did not come from the userland itself. So log an info message when device error reset happens.
For example: BTRFS info (device sdc): device stats zeroed by btrfs(9223)
Reported-by: philip@philip-seeger.de Link: https://www.spinics.net/lists/linux-btrfs/msg96528.html Reviewed-by: Josef Bacik josef@toxicpanda.com Signed-off-by: Anand Jain anand.jain@oracle.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/volumes.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 5bbcdcff68a9e..9c3b394b99fa2 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -7260,6 +7260,8 @@ int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info, else btrfs_dev_stat_reset(dev, i); } + btrfs_info(fs_info, "device stats zeroed by %s (%d)", + current->comm, task_pid_nr(current)); } else { for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) if (stats->nr_items > i)