| Message ID | 20110518220125.GA26835@redhat.com |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On Thu, 19 May 2011 01:01:25 +0300, "Michael S. Tsirkin" <mst@redhat.com> wrote: > The patch virtio_net: limit xmit polling > got the logic reversed: it polled while we had > capacity not while ring was empty. > > Fix it up and clean up a bit by using a for loop. > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > --- > > OK, turns out that patch was borken. Here's > a fix that survived stress test on my box. > Pushed on my branch, I'll send a rebased series > with Rusty's comments addressed ASAP. Normally you would have missed the merge window by now, but I'd really like this stuff in, so I'm holding it open for this. I want these patches in linux-next for at least a few days before I push them. If you think we're not close enough, please tell me and I'll push the rest of the virtio patches to Linus now. Thanks, Rusty. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, May 19, 2011 at 05:00:17PM +0930, Rusty Russell wrote: > On Thu, 19 May 2011 01:01:25 +0300, "Michael S. Tsirkin" <mst@redhat.com> wrote: > > The patch virtio_net: limit xmit polling > > got the logic reversed: it polled while we had > > capacity not while ring was empty. > > > > Fix it up and clean up a bit by using a for loop. > > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com> > > --- > > > > OK, turns out that patch was borken. Here's > > a fix that survived stress test on my box. > > Pushed on my branch, I'll send a rebased series > > with Rusty's comments addressed ASAP. > > Normally you would have missed the merge window by now, but I'd really > like this stuff in, so I'm holding it open for this. I want these patches > in linux-next for at least a few days before I push them. > > If you think we're not close enough, please tell me and I'll push > the rest of the virtio patches to Linus now. > > Thanks, > Rusty. I think it makes sense to push just the patches you have applied by now (event index + delayed callback) - the rest are close but they are guest only patches so very easy to experiment with out of tree. OTOH if event index misses the window it makes testing painful as we have to keep patching both host and guest.
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 9982bd7..c8cd22d 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -514,12 +514,14 @@ static bool free_old_xmit_skbs(struct virtnet_info *vi, int capacity) struct sk_buff *skb; unsigned int len; bool c; + int n; + /* We try to free up at least 2 skbs per one sent, so that we'll get * all of the memory back if they are used fast enough. */ - int n = 2; - - while ((c = virtqueue_get_capacity(vi->svq) >= capacity) && --n > 0 && - (skb = virtqueue_get_buf(vi->svq, &len)) != NULL) { + for (n = 0; + ((c = virtqueue_get_capacity(vi->svq)) < capacity || n < 2) && + ((skb = virtqueue_get_buf(vi->svq, &len))); + ++n) { pr_debug("Sent skb %p\n", skb); vi->dev->stats.tx_bytes += skb->len; vi->dev->stats.tx_packets++;
The patch virtio_net: limit xmit polling got the logic reversed: it polled while we had capacity not while ring was empty. Fix it up and clean up a bit by using a for loop. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> --- OK, turns out that patch was borken. Here's a fix that survived stress test on my box. Pushed on my branch, I'll send a rebased series with Rusty's comments addressed ASAP. drivers/net/virtio_net.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-)