[PATCH 5/9] btrfs: add WARN_ON() to check is space_info op current

From: Zhaolei <zhaolei@cn.fujitsu.com>
To: <linux-btrfs@vger.kernel.org>
Cc: Zhao Lei <zhaolei@cn.fujitsu.com>
Subject: [PATCH 5/9] btrfs: add WARN_ON() to check is space_info op current
Date: Fri, 3 Apr 2015 20:12:00 +0800	[thread overview]
Message-ID: <5a5880519a0191307f400a7ca0689ee83c5da8fc.1428062473.git.zhaolei@cn.fujitsu.com> (raw)
In-Reply-To: <cover.1428062473.git.zhaolei@cn.fujitsu.com>

From: Zhao Lei <zhaolei@cn.fujitsu.com>

space_info's value calculation is some complex and easy to cause
bug, add WARN_ON() to help debug.

Changelog v1->v2:
 Put WARN_ON()s under the ENOSPC_DEBUG mount option.
 Suggested by: David Sterba <dsterba@suse.cz>

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
---
 fs/btrfs/extent-tree.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index e04ea1f..203ac63 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -9464,9 +9464,19 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 
 	spin_lock(&block_group->space_info->lock);
 	list_del_init(&block_group->ro_list);
+
+	if (btrfs_test_opt(root, ENOSPC_DEBUG)) {
+		WARN_ON(block_group->space_info->total_bytes
+			< block_group->key.offset);
+		WARN_ON(block_group->space_info->bytes_readonly
+			< block_group->key.offset);
+		WARN_ON(block_group->space_info->disk_total
+			< block_group->key.offset * factor);
+	}
 	block_group->space_info->total_bytes -= block_group->key.offset;
 	block_group->space_info->bytes_readonly -= block_group->key.offset;
 	block_group->space_info->disk_total -= block_group->key.offset * factor;
+
 	spin_unlock(&block_group->space_info->lock);
 
 	memcpy(&key, &block_group->key, sizeof(key));
-- 
1.8.5.1

