btrfs: remove the refcount warning/check at free_extent_map()

At free_extent_map(), it's pointless to have a WARN_ON() to check if the
refcount of the extent map is zero. Such check is already done by the
refcount_t module and refcount_dec_and_test(), which loudly complains if
we try to decrement a reference count that is currently 0.

The WARN_ON() dates back to the time when used a regular atomic_t type
for the reference counter, before we switched to the refcount_t type.
The main goal of the refcount_t type/module is precisely to catch such
types of bugs and loudly complain if they happen.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Filipe Manana 2022-09-19 15:06:34 +01:00 committed by David Sterba
parent a1ba4c080b
commit ad5d6e9148

View File

@ -74,7 +74,6 @@ void free_extent_map(struct extent_map *em)
{
if (!em)
return;
WARN_ON(refcount_read(&em->refs) == 0);
if (refcount_dec_and_test(&em->refs)) {
WARN_ON(extent_map_in_tree(em));
WARN_ON(!list_empty(&em->list));