diff options
author | Alex Elder <elder@inktank.com> | 2012-10-08 20:37:30 -0700 |
---|---|---|
committer | Alex Elder <elder@inktank.com> | 2012-10-09 22:00:44 -0700 |
commit | 802c6d967fbdcd2cbc91b917425661bb8bbfaade (patch) | |
tree | a5a64ac537fb69ecb1edd55db8346089fecb9f84 /net/ceph | |
parent | 8618e30bc14b06bfafa0f164cca7b0e06451f88a (diff) |
rbd: define common queue_con_delay()
This patch defines a single function, queue_con_delay() to call
queue_delayed_work() for a connection. It basically generalizes
what was previously queue_con() by adding the delay argument.
queue_con() is now a simple helper that passes 0 for its delay.
queue_con_delay() returns 0 if it queued work or an errno if it
did not for some reason.
If con_work() finds the BACKOFF flag set for a connection, it now
calls queue_con_delay() to handle arranging to start again after a
delay.
Note about connection reference counts: con_work() only ever gets
called as a work item function. At the time that work is scheduled,
a reference to the connection is acquired, and the corresponding
con_work() call is then responsible for dropping that reference
before it returns.
Previously, the backoff handling inside con_work() silently handed
off its reference to delayed work it scheduled. Now that
queue_con_delay() is used, a new reference is acquired for the
newly-scheduled work, and the original reference is dropped by the
con->ops->put() call at the end of the function.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Diffstat (limited to 'net/ceph')
-rw-r--r-- | net/ceph/messenger.c | 38 |
1 files changed, 23 insertions, 15 deletions
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 973c16c20c4..66f6f56bcb2 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -2244,22 +2244,33 @@ bad_tag: /* - * Atomically queue work on a connection. Bump @con reference to - * avoid races with connection teardown. + * Atomically queue work on a connection after the specified delay. + * Bump @con reference to avoid races with connection teardown. + * Returns 0 if work was queued, or an error code otherwise. */ -static void queue_con(struct ceph_connection *con) +static int queue_con_delay(struct ceph_connection *con, unsigned long delay) { if (!con->ops->get(con)) { - dout("queue_con %p ref count 0\n", con); - return; + dout("%s %p ref count 0\n", __func__, con); + + return -ENOENT; } - if (!queue_delayed_work(ceph_msgr_wq, &con->work, 0)) { - dout("queue_con %p - already queued\n", con); + if (!queue_delayed_work(ceph_msgr_wq, &con->work, delay)) { + dout("%s %p - already queued\n", __func__, con); con->ops->put(con); - } else { - dout("queue_con %p\n", con); + + return -EBUSY; } + + dout("%s %p %lu\n", __func__, con, delay); + + return 0; +} + +static void queue_con(struct ceph_connection *con) +{ + (void) queue_con_delay(con, 0); } /* @@ -2294,14 +2305,11 @@ restart: if (test_and_clear_bit(CON_FLAG_BACKOFF, &con->flags)) { dout("con_work %p backing off\n", con); - if (queue_delayed_work(ceph_msgr_wq, &con->work, - round_jiffies_relative(con->delay))) { - dout("con_work %p backoff %lu\n", con, con->delay); - mutex_unlock(&con->mutex); - return; - } else { + ret = queue_con_delay(con, round_jiffies_relative(con->delay)); + if (ret) { dout("con_work %p FAILED to back off %lu\n", con, con->delay); + BUG_ON(ret == -ENOENT); set_bit(CON_FLAG_BACKOFF, &con->flags); } goto done; |