Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a83342aa authored by David Sterba's avatar David Sterba
Browse files

btrfs: add comments to barriers before waitqueue_active



Reduce number of undocumented barriers out there.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 33a9eca7
Loading
Loading
Loading
Loading
+3 −0
Original line number Diff line number Diff line
@@ -839,6 +839,9 @@ static void free_workspace(int type, struct list_head *workspace)
	btrfs_compress_op[idx]->free_workspace(workspace);
	atomic_dec(alloc_workspace);
wake:
	/*
	 * Make sure counter is updated before we wake up waiters.
	 */
	smp_mb();
	if (waitqueue_active(workspace_wait))
		wake_up(workspace_wait);
+1 −2
Original line number Diff line number Diff line
@@ -10363,8 +10363,7 @@ void btrfs_end_write_no_snapshoting(struct btrfs_root *root)
{
	percpu_counter_dec(&root->subv_writers->counter);
	/*
	 * Make sure counter is updated before we wake up
	 * waiters.
	 * Make sure counter is updated before we wake up waiters.
	 */
	smp_mb();
	if (waitqueue_active(&root->subv_writers->wait))
+3 −0
Original line number Diff line number Diff line
@@ -280,6 +280,9 @@ void btrfs_tree_unlock(struct extent_buffer *eb)
	if (blockers) {
		WARN_ON(atomic_read(&eb->spinning_writers));
		atomic_dec(&eb->blocking_writers);
		/*
		 * Make sure counter is updated before we wake up waiters.
		 */
		smp_mb();
		if (waitqueue_active(&eb->write_lock_wq))
			wake_up(&eb->write_lock_wq);
+6 −0
Original line number Diff line number Diff line
@@ -345,6 +345,9 @@ int btrfs_dec_test_first_ordered_pending(struct inode *inode,

	if (entry->bytes_left == 0) {
		ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
		/*
		 * Implicit memory barrier after test_and_set_bit
		 */
		if (waitqueue_active(&entry->wait))
			wake_up(&entry->wait);
	} else {
@@ -409,6 +412,9 @@ int btrfs_dec_test_ordered_pending(struct inode *inode,

	if (entry->bytes_left == 0) {
		ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
		/*
		 * Implicit memory barrier after test_and_set_bit
		 */
		if (waitqueue_active(&entry->wait))
			wake_up(&entry->wait);
	} else {
+3 −0
Original line number Diff line number Diff line
@@ -861,6 +861,9 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
	atomic_dec(&cur_trans->num_writers);
	extwriter_counter_dec(cur_trans, trans->type);

	/*
	 * Make sure counter is updated before we wake up waiters.
	 */
	smp_mb();
	if (waitqueue_active(&cur_trans->writer_wait))
		wake_up(&cur_trans->writer_wait);