net/ceph: make ceph_msgr_wq non-reentrant

[pandora-kernel.git] / net / ceph / messenger.c

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 1c7a2ec..dff633d 100644 (file)
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -96,12 +96,10 @@ struct workqueue_struct *ceph_msgr_wq;
 
 int ceph_msgr_init(void)
 {
-       ceph_msgr_wq = create_workqueue("ceph-msgr");
-       if (IS_ERR(ceph_msgr_wq)) {
-               int ret = PTR_ERR(ceph_msgr_wq);
-               pr_err("msgr_init failed to create workqueue: %d\n", ret);
-               ceph_msgr_wq = NULL;
-               return ret;
+       ceph_msgr_wq = alloc_workqueue("ceph-msgr", WQ_NON_REENTRANT, 0);
+       if (!ceph_msgr_wq) {
+               pr_err("msgr_init failed to create workqueue\n");
+               return -ENOMEM;
        }
        return 0;
 }
@@ -1922,20 +1920,6 @@ bad_tag:
 /*
  * Atomically queue work on a connection.  Bump @con reference to
  * avoid races with connection teardown.
- *
- * There is some trickery going on with QUEUED and BUSY because we
- * only want a _single_ thread operating on each connection at any
- * point in time, but we want to use all available CPUs.
- *
- * The worker thread only proceeds if it can atomically set BUSY.  It
- * clears QUEUED and does it's thing.  When it thinks it's done, it
- * clears BUSY, then rechecks QUEUED.. if it's set again, it loops
- * (tries again to set BUSY).
- *
- * To queue work, we first set QUEUED, _then_ if BUSY isn't set, we
- * try to queue work.  If that fails (work is already queued, or BUSY)
- * we give up (work also already being done or is queued) but leave QUEUED
- * set so that the worker thread will loop if necessary.
  */
 static void queue_con(struct ceph_connection *con)
 {
@@ -1950,11 +1934,7 @@ static void queue_con(struct ceph_connection *con)
                return;
        }
 
-       set_bit(QUEUED, &con->state);
-       if (test_bit(BUSY, &con->state)) {
-               dout("queue_con %p - already BUSY\n", con);
-               con->ops->put(con);
-       } else if (!queue_work(ceph_msgr_wq, &con->work.work)) {
+       if (!queue_delayed_work(ceph_msgr_wq, &con->work, 0)) {
                dout("queue_con %p - already queued\n", con);
                con->ops->put(con);
        } else {
@@ -1969,15 +1949,6 @@ static void con_work(struct work_struct *work)
 {
        struct ceph_connection *con = container_of(work, struct ceph_connection,
                                                   work.work);
-       int backoff = 0;
-
-more:
-       if (test_and_set_bit(BUSY, &con->state) != 0) {
-               dout("con_work %p BUSY already set\n", con);
-               goto out;
-       }
-       dout("con_work %p start, clearing QUEUED\n", con);
-       clear_bit(QUEUED, &con->state);
 
        mutex_lock(&con->mutex);
 
@@ -1996,28 +1967,13 @@ more:
            try_read(con) < 0 ||
            try_write(con) < 0) {
                mutex_unlock(&con->mutex);
-               backoff = 1;
                ceph_fault(con);     /* error/fault path */
                goto done_unlocked;
        }
 
 done:
        mutex_unlock(&con->mutex);
-
 done_unlocked:
-       clear_bit(BUSY, &con->state);
-       dout("con->state=%lu\n", con->state);
-       if (test_bit(QUEUED, &con->state)) {
-               if (!backoff || test_bit(OPENING, &con->state)) {
-                       dout("con_work %p QUEUED reset, looping\n", con);
-                       goto more;
-               }
-               dout("con_work %p QUEUED reset, but just faulted\n", con);
-               clear_bit(QUEUED, &con->state);
-       }
-       dout("con_work %p done\n", con);
-
-out:
        con->ops->put(con);
 }