Btrfs: init worker struct fields before kthread-run

This patch fixes a bug which may result race condition
between btrfs_start_workers() and worker_loop().

btrfs_start_workers() executed in a parent thread writes
on workers->worker and worker_loop() in a child thread
reads workers->worker. However, there is no synchronization
enforcing the order of two operations.

This patch makes btrfs_start_workers() fill workers->worker
before it starts a child thread with worker_loop()

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Shin Hong 2009-06-10 20:11:29 -04:00 committed by Chris Mason
parent 4eedeb75e7
commit fd0fb038d5
1 changed files with 1 additions and 1 deletions

View File

@ -294,10 +294,10 @@ int btrfs_start_workers(struct btrfs_workers *workers, int num_workers)
INIT_LIST_HEAD(&worker->worker_list);
spin_lock_init(&worker->lock);
atomic_set(&worker->num_pending, 0);
worker->workers = workers;
worker->task = kthread_run(worker_loop, worker,
"btrfs-%s-%d", workers->name,
workers->num_workers + i);
worker->workers = workers;
if (IS_ERR(worker->task)) {
kfree(worker);
ret = PTR_ERR(worker->task);