btrfs_put_delayed_ref(&head->node);
goto search_again;
}
+ spin_lock(&head->lock);
if (head->extent_op && head->extent_op->update_flags)
extent_flags |= head->extent_op->flags_to_set;
else
BUG_ON(num_refs == 0);
num_refs += head->node.ref_mod;
+ spin_unlock(&head->lock);
mutex_unlock(&head->mutex);
}
spin_unlock(&delayed_refs->lock);
select_delayed_ref(struct btrfs_delayed_ref_head *head)
{
struct rb_node *node;
- struct btrfs_delayed_ref_node *ref;
- int action = BTRFS_ADD_DELAYED_REF;
-again:
+ struct btrfs_delayed_ref_node *ref, *last = NULL;;
+
/*
* select delayed ref of type BTRFS_ADD_DELAYED_REF first.
* this prevents ref count from going down to zero when
* there still are pending delayed ref.
*/
- node = rb_prev(&head->node.rb_node);
- while (1) {
- if (!node)
- break;
+ node = rb_first(&head->ref_root);
+ while (node) {
ref = rb_entry(node, struct btrfs_delayed_ref_node,
rb_node);
- if (ref->bytenr != head->node.bytenr)
- break;
- if (ref->action == action)
+ if (ref->action == BTRFS_ADD_DELAYED_REF)
return ref;
- node = rb_prev(node);
- }
- if (action == BTRFS_ADD_DELAYED_REF) {
- action = BTRFS_DROP_DELAYED_REF;
- goto again;
+ else if (last == NULL)
+ last = ref;
+ node = rb_next(node);
}
- return NULL;
+ return last;
}
/*
* Returns 0 on success or if called with an already aborted transaction.
* Returns -ENOMEM or -EIO on failure and will abort the transaction.
*/
-static noinline int run_clustered_refs(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct list_head *cluster)
+static noinline int __btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ unsigned long nr)
{
struct btrfs_delayed_ref_root *delayed_refs;
struct btrfs_delayed_ref_node *ref;
struct btrfs_delayed_extent_op *extent_op;
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
- int count = 0;
+ unsigned long count = 0;
int must_insert_reserved = 0;
delayed_refs = &trans->transaction->delayed_refs;
while (1) {
if (!locked_ref) {
- /* pick a new head ref from the cluster list */
- if (list_empty(cluster))
+ if (count >= nr)
break;
- locked_ref = list_entry(cluster->next,
- struct btrfs_delayed_ref_head, cluster);
+ spin_lock(&delayed_refs->lock);
+ locked_ref = btrfs_select_ref_head(trans);
+ if (!locked_ref) {
+ spin_unlock(&delayed_refs->lock);
+ break;
+ }
/* grab the lock that says we are going to process
* all the refs for this head */
ret = btrfs_delayed_ref_lock(trans, locked_ref);
-
+ spin_unlock(&delayed_refs->lock);
/*
* we may have dropped the spin lock to get the head
* mutex lock, and that might have given someone else
* finish. If we merged anything we need to re-loop so we can
* get a good ref.
*/
+ spin_lock(&locked_ref->lock);
btrfs_merge_delayed_refs(trans, fs_info, delayed_refs,
locked_ref);
if (ref && ref->seq &&
btrfs_check_delayed_seq(fs_info, delayed_refs, ref->seq)) {
- /*
- * there are still refs with lower seq numbers in the
- * process of being added. Don't run this ref yet.
- */
- list_del_init(&locked_ref->cluster);
+ spin_unlock(&locked_ref->lock);
btrfs_delayed_ref_unlock(locked_ref);
- locked_ref = NULL;
+ spin_lock(&delayed_refs->lock);
+ locked_ref->processing = 0;
delayed_refs->num_heads_ready++;
spin_unlock(&delayed_refs->lock);
+ locked_ref = NULL;
cond_resched();
- spin_lock(&delayed_refs->lock);
continue;
}
locked_ref->extent_op = NULL;
if (!ref) {
+
+
/* All delayed refs have been processed, Go ahead
* and send the head node to run_one_delayed_ref,
* so that any accounting fixes can happen
}
if (extent_op) {
- spin_unlock(&delayed_refs->lock);
-
+ spin_unlock(&locked_ref->lock);
ret = run_delayed_extent_op(trans, root,
ref, extent_op);
btrfs_free_delayed_extent_op(extent_op);
*/
if (must_insert_reserved)
locked_ref->must_insert_reserved = 1;
+ locked_ref->processing = 0;
btrfs_debug(fs_info, "run_delayed_extent_op returned %d", ret);
- spin_lock(&delayed_refs->lock);
btrfs_delayed_ref_unlock(locked_ref);
return ret;
}
-
- goto next;
+ continue;
}
- }
- ref->in_tree = 0;
- rb_erase(&ref->rb_node, &delayed_refs->root);
- if (btrfs_delayed_ref_is_head(ref)) {
+ /*
+ * Need to drop our head ref lock and re-aqcuire the
+ * delayed ref lock and then re-check to make sure
+ * nobody got added.
+ */
+ spin_unlock(&locked_ref->lock);
+ spin_lock(&delayed_refs->lock);
+ spin_lock(&locked_ref->lock);
+ if (rb_first(&locked_ref->ref_root)) {
+ spin_unlock(&locked_ref->lock);
+ spin_unlock(&delayed_refs->lock);
+ continue;
+ }
+ ref->in_tree = 0;
+ delayed_refs->num_heads--;
rb_erase(&locked_ref->href_node,
&delayed_refs->href_root);
+ spin_unlock(&delayed_refs->lock);
+ } else {
+ ref->in_tree = 0;
+ rb_erase(&ref->rb_node, &locked_ref->ref_root);
}
- delayed_refs->num_entries--;
+ atomic_dec(&delayed_refs->num_entries);
+
if (!btrfs_delayed_ref_is_head(ref)) {
/*
* when we play the delayed ref, also correct the
default:
WARN_ON(1);
}
- } else {
- list_del_init(&locked_ref->cluster);
}
- spin_unlock(&delayed_refs->lock);
+ spin_unlock(&locked_ref->lock);
ret = run_one_delayed_ref(trans, root, ref, extent_op,
must_insert_reserved);
btrfs_free_delayed_extent_op(extent_op);
if (ret) {
+ locked_ref->processing = 0;
btrfs_delayed_ref_unlock(locked_ref);
btrfs_put_delayed_ref(ref);
btrfs_debug(fs_info, "run_one_delayed_ref returned %d", ret);
- spin_lock(&delayed_refs->lock);
return ret;
}
}
btrfs_put_delayed_ref(ref);
count++;
-next:
cond_resched();
- spin_lock(&delayed_refs->lock);
}
- return count;
+ return 0;
}
#ifdef SCRAMBLE_DELAYED_REFS
return ret;
}
-static int refs_newer(struct btrfs_delayed_ref_root *delayed_refs, int seq,
- int count)
-{
- int val = atomic_read(&delayed_refs->ref_seq);
-
- if (val < seq || val >= seq + count)
- return 1;
- return 0;
-}
-
static inline u64 heads_to_leaves(struct btrfs_root *root, u64 heads)
{
u64 num_bytes;
struct rb_node *node;
struct btrfs_delayed_ref_root *delayed_refs;
struct btrfs_delayed_ref_head *head;
- struct list_head cluster;
int ret;
- u64 delayed_start;
int run_all = count == (unsigned long)-1;
int run_most = 0;
- int loops;
/* We'll clean this up in btrfs_cleanup_transaction */
if (trans->aborted)
btrfs_delayed_refs_qgroup_accounting(trans, root->fs_info);
delayed_refs = &trans->transaction->delayed_refs;
- INIT_LIST_HEAD(&cluster);
if (count == 0) {
- count = delayed_refs->num_entries * 2;
+ count = atomic_read(&delayed_refs->num_entries) * 2;
run_most = 1;
}
- if (!run_all && !run_most) {
- int old;
- int seq = atomic_read(&delayed_refs->ref_seq);
-
-progress:
- old = atomic_cmpxchg(&delayed_refs->procs_running_refs, 0, 1);
- if (old) {
- DEFINE_WAIT(__wait);
- if (delayed_refs->flushing ||
- !btrfs_should_throttle_delayed_refs(trans, root))
- return 0;
-
- prepare_to_wait(&delayed_refs->wait, &__wait,
- TASK_UNINTERRUPTIBLE);
-
- old = atomic_cmpxchg(&delayed_refs->procs_running_refs, 0, 1);
- if (old) {
- schedule();
- finish_wait(&delayed_refs->wait, &__wait);
-
- if (!refs_newer(delayed_refs, seq, 256))
- goto progress;
- else
- return 0;
- } else {
- finish_wait(&delayed_refs->wait, &__wait);
- goto again;
- }
- }
-
- } else {
- atomic_inc(&delayed_refs->procs_running_refs);
- }
-
again:
- loops = 0;
- spin_lock(&delayed_refs->lock);
-
#ifdef SCRAMBLE_DELAYED_REFS
delayed_refs->run_delayed_start = find_middle(&delayed_refs->root);
#endif
-
- while (1) {
- if (!(run_all || run_most) &&
- !btrfs_should_throttle_delayed_refs(trans, root))
- break;
-
- /*
- * go find something we can process in the rbtree. We start at
- * the beginning of the tree, and then build a cluster
- * of refs to process starting at the first one we are able to
- * lock
- */
- delayed_start = delayed_refs->run_delayed_start;
- ret = btrfs_find_ref_cluster(trans, &cluster,
- delayed_refs->run_delayed_start);
- if (ret)
- break;
-
- ret = run_clustered_refs(trans, root, &cluster);
- if (ret < 0) {
- btrfs_release_ref_cluster(&cluster);
- spin_unlock(&delayed_refs->lock);
- btrfs_abort_transaction(trans, root, ret);
- atomic_dec(&delayed_refs->procs_running_refs);
- wake_up(&delayed_refs->wait);
- return ret;
- }
-
- atomic_add(ret, &delayed_refs->ref_seq);
-
- count -= min_t(unsigned long, ret, count);
-
- if (count == 0)
- break;
-
- if (delayed_start >= delayed_refs->run_delayed_start) {
- if (loops == 0) {
- /*
- * btrfs_find_ref_cluster looped. let's do one
- * more cycle. if we don't run any delayed ref
- * during that cycle (because we can't because
- * all of them are blocked), bail out.
- */
- loops = 1;
- } else {
- /*
- * no runnable refs left, stop trying
- */
- BUG_ON(run_all);
- break;
- }
- }
- if (ret) {
- /* refs were run, let's reset staleness detection */
- loops = 0;
- }
+ ret = __btrfs_run_delayed_refs(trans, root, count);
+ if (ret < 0) {
+ btrfs_abort_transaction(trans, root, ret);
+ return ret;
}
if (run_all) {
- if (!list_empty(&trans->new_bgs)) {
- spin_unlock(&delayed_refs->lock);
+ if (!list_empty(&trans->new_bgs))
btrfs_create_pending_block_groups(trans, root);
- spin_lock(&delayed_refs->lock);
- }
+ spin_lock(&delayed_refs->lock);
node = rb_first(&delayed_refs->href_root);
- if (!node)
+ if (!node) {
+ spin_unlock(&delayed_refs->lock);
goto out;
+ }
count = (unsigned long)-1;
while (node) {
node = rb_next(node);
}
spin_unlock(&delayed_refs->lock);
- schedule_timeout(1);
+ cond_resched();
goto again;
}
out:
- atomic_dec(&delayed_refs->procs_running_refs);
- smp_mb();
- if (waitqueue_active(&delayed_refs->wait))
- wake_up(&delayed_refs->wait);
-
- spin_unlock(&delayed_refs->lock);
assert_qgroups_uptodate(trans);
return 0;
}
struct rb_node *node;
int ret = 0;
- ret = -ENOENT;
delayed_refs = &trans->transaction->delayed_refs;
spin_lock(&delayed_refs->lock);
head = btrfs_find_delayed_ref_head(trans, bytenr);
- if (!head)
- goto out;
+ if (!head) {
+ spin_unlock(&delayed_refs->lock);
+ return 0;
+ }
if (!mutex_trylock(&head->mutex)) {
atomic_inc(&head->node.refs);
btrfs_put_delayed_ref(&head->node);
return -EAGAIN;
}
+ spin_unlock(&delayed_refs->lock);
- node = rb_prev(&head->node.rb_node);
- if (!node)
- goto out_unlock;
-
- ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
-
- if (ref->bytenr != bytenr)
- goto out_unlock;
+ spin_lock(&head->lock);
+ node = rb_first(&head->ref_root);
+ while (node) {
+ ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
+ node = rb_next(node);
- ret = 1;
- if (ref->type != BTRFS_EXTENT_DATA_REF_KEY)
- goto out_unlock;
+ /* If it's a shared ref we know a cross reference exists */
+ if (ref->type != BTRFS_EXTENT_DATA_REF_KEY) {
+ ret = 1;
+ break;
+ }
- data_ref = btrfs_delayed_node_to_data_ref(ref);
+ data_ref = btrfs_delayed_node_to_data_ref(ref);
- node = rb_prev(node);
- if (node) {
- int seq = ref->seq;
-
- ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
- if (ref->bytenr == bytenr && ref->seq == seq)
- goto out_unlock;
+ /*
+ * If our ref doesn't match the one we're currently looking at
+ * then we have a cross reference.
+ */
+ if (data_ref->root != root->root_key.objectid ||
+ data_ref->objectid != objectid ||
+ data_ref->offset != offset) {
+ ret = 1;
+ break;
+ }
}
-
- if (data_ref->root != root->root_key.objectid ||
- data_ref->objectid != objectid || data_ref->offset != offset)
- goto out_unlock;
-
- ret = 0;
-out_unlock:
+ spin_unlock(&head->lock);
mutex_unlock(&head->mutex);
-out:
- spin_unlock(&delayed_refs->lock);
return ret;
}
{
struct btrfs_delayed_ref_head *head;
struct btrfs_delayed_ref_root *delayed_refs;
- struct btrfs_delayed_ref_node *ref;
- struct rb_node *node;
int ret = 0;
delayed_refs = &trans->transaction->delayed_refs;
if (!head)
goto out;
- node = rb_prev(&head->node.rb_node);
- if (!node)
- goto out;
-
- ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
-
- /* there are still entries for this ref, we can't drop it */
- if (ref->bytenr == bytenr)
+ spin_lock(&head->lock);
+ if (rb_first(&head->ref_root))
goto out;
if (head->extent_op) {
* ahead and process it.
*/
head->node.in_tree = 0;
- rb_erase(&head->node.rb_node, &delayed_refs->root);
rb_erase(&head->href_node, &delayed_refs->href_root);
- delayed_refs->num_entries--;
+ atomic_dec(&delayed_refs->num_entries);
/*
* we don't take a ref on the node because we're removing it from the
* tree, so we just steal the ref the tree was holding.
*/
delayed_refs->num_heads--;
- if (list_empty(&head->cluster))
+ if (head->processing == 0)
delayed_refs->num_heads_ready--;
-
- list_del_init(&head->cluster);
+ head->processing = 0;
+ spin_unlock(&head->lock);
spin_unlock(&delayed_refs->lock);
BUG_ON(head->extent_op);
btrfs_put_delayed_ref(&head->node);
return ret;
out:
+ spin_unlock(&head->lock);
spin_unlock(&delayed_refs->lock);
return 0;
}
projects / profile / ivi / kernel-x86-ivi.git / blobdiff