Btrfs: Add leak debugging for extent_buffer and extent_state
This also fixes one leak around the super block when failing to mount the
FS.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 6dab664..b99cfab 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -26,6 +26,7 @@
static LIST_HEAD(buffers);
static LIST_HEAD(states);
+static spinlock_t leak_lock = SPIN_LOCK_UNLOCKED;
#define BUFFER_LRU_MAX 64
@@ -64,15 +65,22 @@
void extent_io_exit(void)
{
struct extent_state *state;
+ struct extent_buffer *eb;
while (!list_empty(&states)) {
- state = list_entry(states.next, struct extent_state, list);
+ state = list_entry(states.next, struct extent_state, leak_list);
printk("state leak: start %Lu end %Lu state %lu in tree %p refs %d\n", state->start, state->end, state->state, state->tree, atomic_read(&state->refs));
- list_del(&state->list);
+ list_del(&state->leak_list);
kmem_cache_free(extent_state_cache, state);
}
+ while (!list_empty(&buffers)) {
+ eb = list_entry(buffers.next, struct extent_buffer, leak_list);
+ printk("buffer leak start %Lu len %lu refs %d\n", eb->start, eb->len, atomic_read(&eb->refs));
+ list_del(&eb->leak_list);
+ kmem_cache_free(extent_buffer_cache, eb);
+ }
if (extent_state_cache)
kmem_cache_destroy(extent_state_cache);
if (extent_buffer_cache)
@@ -109,6 +117,7 @@
struct extent_state *alloc_extent_state(gfp_t mask)
{
struct extent_state *state;
+ unsigned long flags;
state = kmem_cache_alloc(extent_state_cache, mask);
if (!state || IS_ERR(state))
@@ -116,6 +125,9 @@
state->state = 0;
state->private = 0;
state->tree = NULL;
+ spin_lock_irqsave(&leak_lock, flags);
+ list_add(&state->leak_list, &states);
+ spin_unlock_irqrestore(&leak_lock, flags);
atomic_set(&state->refs, 1);
init_waitqueue_head(&state->wq);
@@ -128,7 +140,11 @@
if (!state)
return;
if (atomic_dec_and_test(&state->refs)) {
+ unsigned long flags;
WARN_ON(state->tree);
+ spin_lock_irqsave(&leak_lock, flags);
+ list_del(&state->leak_list);
+ spin_unlock_irqrestore(&leak_lock, flags);
kmem_cache_free(extent_state_cache, state);
}
}
@@ -2582,6 +2598,7 @@
gfp_t mask)
{
struct extent_buffer *eb = NULL;
+ unsigned long flags;
spin_lock(&tree->lru_lock);
eb = find_lru(tree, start, len);
@@ -2594,6 +2611,9 @@
INIT_LIST_HEAD(&eb->lru);
eb->start = start;
eb->len = len;
+ spin_lock_irqsave(&leak_lock, flags);
+ list_add(&eb->leak_list, &buffers);
+ spin_unlock_irqrestore(&leak_lock, flags);
atomic_set(&eb->refs, 1);
return eb;
@@ -2601,6 +2621,10 @@
static void __free_extent_buffer(struct extent_buffer *eb)
{
+ unsigned long flags;
+ spin_lock_irqsave(&leak_lock, flags);
+ list_del(&eb->leak_list);
+ spin_unlock_irqrestore(&leak_lock, flags);
kmem_cache_free(extent_buffer_cache, eb);
}