diff options
| author | David Vrabel <david.vrabel@citrix.com> | 2015-02-02 19:57:51 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-02-03 06:39:04 +0300 |
| commit | 42b5212fee4f57907e9415b18fe19c13e65574bc (patch) | |
| tree | 3fb44adcfd6de16f9e3ceddcf46d7a2c9c54532c | |
| parent | 5a2e87b16875f9b83b7e9494cf1fce8e17dc764a (diff) | |
| download | linux-42b5212fee4f57907e9415b18fe19c13e65574bc.tar.xz | |
xen-netback: stop the guest rx thread after a fatal error
After commit e9d8b2c2968499c1f96563e6522c56958d5a1d0d (xen-netback:
disable rogue vif in kthread context), a fatal (protocol) error would
leave the guest Rx thread spinning, wasting CPU time. Commit
ecf08d2dbb96d5a4b4bcc53a39e8d29cc8fef02e (xen-netback: reintroduce
guest Rx stall detection) made this even worse by removing a
cond_resched() from this path.
Since a fatal error is non-recoverable, just allow the guest Rx thread
to exit. This requires taking additional refs to the task so the
thread exiting early is handled safely.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Julien Grall <julien.grall@linaro.org>
Tested-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/xen-netback/interface.c | 2 | ||||
| -rw-r--r-- | drivers/net/xen-netback/netback.c | 3 |
2 files changed, 3 insertions, 2 deletions
diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 9259a732e8a4..037f74f0fcf6 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -578,6 +578,7 @@ int xenvif_connect(struct xenvif_queue *queue, unsigned long tx_ring_ref, goto err_rx_unbind; } queue->task = task; + get_task_struct(task); task = kthread_create(xenvif_dealloc_kthread, (void *)queue, "%s-dealloc", queue->name); @@ -634,6 +635,7 @@ void xenvif_disconnect(struct xenvif *vif) if (queue->task) { kthread_stop(queue->task); + put_task_struct(queue->task); queue->task = NULL; } diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 908e65e9b821..c8ce701a7efb 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -2109,8 +2109,7 @@ int xenvif_kthread_guest_rx(void *data) */ if (unlikely(vif->disabled && queue->id == 0)) { xenvif_carrier_off(vif); - xenvif_rx_queue_purge(queue); - continue; + break; } if (!skb_queue_empty(&queue->rx_queue)) |