btrfs: qgroup: move noisy underflow warning to debugging build

The WARN_ON and warning from report_reserved_underflow can become very
noisy and is visible unconditionally although this is namely for
debugging. The patch "btrfs: Add WARN_ON for qgroup reserved underflow"
(18dc22c19bef520cca11ce4c0807ac9dec48d31f) went to 4.11-rc1 and the plan
was to get the fix as well, but this hasn't happened.

CC: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index a59801dc2a34..afbea61d957e 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1042,9 +1042,12 @@ static void report_reserved_underflow(struct btrfs_fs_info *fs_info,
                                       struct btrfs_qgroup *qgroup,
                                       u64 num_bytes)
 {
-        btrfs_warn(fs_info,
+#ifdef CONFIG_BTRFS_DEBUG
+        WARN_ON(qgroup->reserved < num_bytes);
+        btrfs_debug(fs_info,
                 "qgroup %llu reserved space underflow, have: %llu, to free: %llu",
                 qgroup->qgroupid, qgroup->reserved, num_bytes);
+#endif
         qgroup->reserved = 0;
 }
 /*
@@ -1075,7 +1078,7 @@ static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
         qgroup->excl += sign * num_bytes;
         qgroup->excl_cmpr += sign * num_bytes;
         if (sign > 0) {
-                if (WARN_ON(qgroup->reserved < num_bytes))
+                if (qgroup->reserved < num_bytes)
                         report_reserved_underflow(fs_info, qgroup, num_bytes);
                 else
                         qgroup->reserved -= num_bytes;
@@ -1100,7 +1103,7 @@ static int __qgroup_excl_accounting(struct btrfs_fs_info *fs_info,
                 WARN_ON(sign < 0 && qgroup->excl < num_bytes);
                 qgroup->excl += sign * num_bytes;
                 if (sign > 0) {
-                        if (WARN_ON(qgroup->reserved < num_bytes))
+                        if (qgroup->reserved < num_bytes)
                                 report_reserved_underflow(fs_info, qgroup,
                                                           num_bytes);
                         else
@@ -2469,7 +2472,7 @@ void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
 
                 qg = unode_aux_to_qgroup(unode);
 
-                if (WARN_ON(qg->reserved < num_bytes))
+                if (qg->reserved < num_bytes)
                         report_reserved_underflow(fs_info, qg, num_bytes);
                 else
                         qg->reserved -= num_bytes;