From dfa523ae9f2542bee4cddaea37b3be3e157f6e6b Mon Sep 17 00:00:00 2001 From: Wei Liu Date: Wed, 21 Jun 2017 10:21:22 +0100 Subject: xen-netback: correctly schedule rate-limited queues Add a flag to indicate if a queue is rate-limited. Test the flag in NAPI poll handler and avoid rescheduling the queue if true, otherwise we risk locking up the host. The rescheduling will be done in the timer callback function. Reported-by: Jean-Louis Dupond Signed-off-by: Wei Liu Tested-by: Jean-Louis Dupond Reviewed-by: Paul Durrant Signed-off-by: David S. Miller --- drivers/net/xen-netback/interface.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'drivers/net/xen-netback/interface.c') diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 8397f6c92451..e322a862ddfe 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -106,7 +106,11 @@ static int xenvif_poll(struct napi_struct *napi, int budget) if (work_done < budget) { napi_complete_done(napi, work_done); - xenvif_napi_schedule_or_enable_events(queue); + /* If the queue is rate-limited, it shall be + * rescheduled in the timer callback. + */ + if (likely(!queue->rate_limited)) + xenvif_napi_schedule_or_enable_events(queue); } return work_done; -- cgit v1.2.1