btrfs: use verbose assert at peek_discard_list()

We now have a verbose variant of ASSERT() so that we can print the value
of the block group's discard_index. So use it for better problem analysis
in case the assertion is triggered.

Reviewed-by: Boris Burkov <boris@bur.io>
Reviewed-by: Daniel Vacek <neelx@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/discard.c b/fs/btrfs/discard.c
index de23c4b3515e5882cc7fa7f53af171c6d8c64faa..89fe85778115ab25dc5cd812a1c0f98857768457 100644 (file)
--- a/fs/btrfs/discard.c
+++ b/fs/btrfs/discard.c
@@ -256,7 +256,9 @@ again:
                                 * the discard lists.
                                 */
                                ASSERT(block_group->discard_index !=
-                                      BTRFS_DISCARD_INDEX_UNUSED);
+                                      BTRFS_DISCARD_INDEX_UNUSED,
+                                      "discard_index=%d",
+                                      block_group->discard_index);
                        } else {
                                list_del_init(&block_group->discard_list);
                                btrfs_put_block_group(block_group);