static void ext4_mb_pa_free(struct ext4_allocation_context *ac)
{
	struct ext4_prealloc_space *pa = ac->ac_pa;

	BUG_ON(!pa);
	ac->ac_pa = NULL;
	WARN_ON(!atomic_dec_and_test(&pa->pa_count));
	kmem_cache_free(ext4_pspace_cachep, pa);
}
static void ext4_mb_pa_free(struct ext4_allocation_context *ac)
{
	struct ext4_prealloc_space *pa = ac->ac_pa;

	BUG_ON(!pa);
	ac->ac_pa = NULL;
	WARN_ON(!atomic_dec_and_test(&pa->pa_count));
	kmem_cache_free(ext4_pspace_cachep, pa);
}