diff options
| author | David S. Miller <davem@davemloft.net> | 2008-08-13 15:18:38 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-08-13 15:18:38 -0700 |
| commit | b9a3b1102bc80b4044224494100f67de132d5448 (patch) | |
| tree | 26d693207ad5c5e9ea79a2b21de48b1e409f628e | |
| parent | 26b284de54a5ca3dfbe2fd9a51ac1923e80085a2 (diff) | |
pkt_sched: Fix queue quiescence testing in dev_deactivate().
Based upon discussions with Jarek P. and Herbert Xu.
First, we're testing the wrong qdisc. We just reset the device
queue qdiscs to &noop_qdisc and checking it's state is completely
pointless here.
We want to wait until the previous qdisc that was sitting at
the ->qdisc pointer is not busy any more. And that would be
->qdisc_sleeping.
Because of how we propagate the samples qdisc pointer down into
qdisc_run and friends via per-cpu ->output_queue and netif_schedule,
we have to wait also for the __QDISC_STATE_SCHED bit to clear as
well.
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/sched/sch_generic.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 7cf83b37459d..468574682caa 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -647,7 +647,7 @@ static void dev_deactivate_queue(struct net_device *dev, } } -static bool some_qdisc_is_running(struct net_device *dev, int lock) +static bool some_qdisc_is_busy(struct net_device *dev, int lock) { unsigned int i; @@ -658,13 +658,14 @@ static bool some_qdisc_is_running(struct net_device *dev, int lock) int val; dev_queue = netdev_get_tx_queue(dev, i); - q = dev_queue->qdisc; + q = dev_queue->qdisc_sleeping; root_lock = qdisc_lock(q); if (lock) spin_lock_bh(root_lock); - val = test_bit(__QDISC_STATE_RUNNING, &q->state); + val = (test_bit(__QDISC_STATE_RUNNING, &q->state) || + test_bit(__QDISC_STATE_SCHED, &q->state)); if (lock) spin_unlock_bh(root_lock); @@ -689,14 +690,14 @@ void dev_deactivate(struct net_device *dev) /* Wait for outstanding qdisc_run calls. */ do { - while (some_qdisc_is_running(dev, 0)) + while (some_qdisc_is_busy(dev, 0)) yield(); /* * Double-check inside queue lock to ensure that all effects * of the queue run are visible when we return. */ - running = some_qdisc_is_running(dev, 1); + running = some_qdisc_is_busy(dev, 1); /* * The running flag should never be set at this point because |