similar to: [PATCH net-next] virtio-net: batch stats updating

From: Eric Dumazet <edumazet at google.com> commit 3fa2a1df909 (virtio-net: per cpu 64 bit stats (v2)) added a race on 32bit arches. We must use separate syncp for rx and tx path as they can be run at the same time on different cpus. Thus one sequence increment can be lost and readers spin forever. Signed-off-by: Eric Dumazet <edumazet at google.com> Cc: Stephen Hemminger

From: Eric Dumazet <edumazet at google.com> commit 3fa2a1df909 (virtio-net: per cpu 64 bit stats (v2)) added a race on 32bit arches. We must use separate syncp for rx and tx path as they can be run at the same time on different cpus. Thus one sequence increment can be lost and readers spin forever. Signed-off-by: Eric Dumazet <edumazet at google.com> Cc: Stephen Hemminger

The main purpose of this patch is adding a way of checking per-queue stats. It's useful to debug performance problems on multiqueue environment. $ ethtool -S ens10 NIC statistics: rx_queue_0_packets: 2090408 rx_queue_0_bytes: 3164825094 rx_queue_1_packets: 2082531 rx_queue_1_bytes: 3152932314 tx_queue_0_packets: 2770841 tx_queue_0_bytes: 4194955474

The main purpose of this patch is adding a way of checking per-queue stats. It's useful to debug performance problems on multiqueue environment. $ ethtool -S ens10 NIC statistics: rx_packets: 4172939 tx_packets: 5855538 rx_bytes: 6317757408 tx_bytes: 8865151846 rx_dropped: 0 rx_length_errors: 0 rx_frame_errors: 0 tx_dropped: 0 tx_fifo_errors: 0

The main purpose of this patch is adding a way of checking per-queue stats. It's useful to debug performance problems on multiqueue environment. $ ethtool -S ens10 NIC statistics: rx_packets: 4172939 tx_packets: 5855538 rx_bytes: 6317757408 tx_bytes: 8865151846 rx_dropped: 0 rx_length_errors: 0 rx_frame_errors: 0 tx_dropped: 0 tx_fifo_errors: 0

Accumulate the sent packets and sent bytes in local variables and perform a single u64_stats_update_begin/end() after. Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: Michael S. Tsirkin <mst at redhat.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/net/virtio_net.c | 12 ++++++++---- 1 files changed, 8 insertions(+), 4 deletions(-) diff --git

Accumulate the sent packets and sent bytes in local variables and perform a single u64_stats_update_begin/end() after. Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: Michael S. Tsirkin <mst at redhat.com> Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/net/virtio_net.c | 12 ++++++++---- 1 files changed, 8 insertions(+), 4 deletions(-) diff --git

On Sat, 2014-10-11 at 15:16 +0800, Jason Wang wrote: > We free transmitted packets in ndo_start_xmit() in the past to get better > performance in the past. One side effect is that skb_orphan() needs to be > called in ndo_start_xmit() which makes sk_wmem_alloc not accurate in > fact. For TCP protocol, this means several optimization could not work well > such as TCP small queue and

This patch allows virtio-net driver to report traffic distribution to inbound/outbound queues through ethtool -S. The per_cpu virtnet_stats is split into receive and transmit stats and are maintained on a per receive_queue and send_queue basis. virtnet_stats() is modified to aggregate interface level statistics from per-queue statistics. Sample output below: NIC statistics: rxq0:

This patch allows virtio-net driver to report traffic distribution to inbound/outbound queues through ethtool -S. The per_cpu virtnet_stats is split into receive and transmit stats and are maintained on a per receive_queue and send_queue basis. virtnet_stats() is modified to aggregate interface level statistics from per-queue statistics. Sample output below: NIC statistics: rxq0:

From: Of Michael S. Tsirkin > On Wed, Oct 15, 2014 at 03:25:27PM +0800, Jason Wang wrote: > > Accumulate the sent packets and sent bytes in local variables and perform a > > single u64_stats_update_begin/end() after. > > > > Cc: Rusty Russell <rusty at rustcorp.com.au> > > Cc: Michael S. Tsirkin <mst at redhat.com> > > Signed-off-by: Jason Wang

From: Of Michael S. Tsirkin > On Wed, Oct 15, 2014 at 03:25:27PM +0800, Jason Wang wrote: > > Accumulate the sent packets and sent bytes in local variables and perform a > > single u64_stats_update_begin/end() after. > > > > Cc: Rusty Russell <rusty at rustcorp.com.au> > > Cc: Michael S. Tsirkin <mst at redhat.com> > > Signed-off-by: Jason Wang

From: Michael S. Tsirkin > On Wed, Oct 15, 2014 at 09:49:01AM +0000, David Laight wrote: > > From: Of Michael S. Tsirkin > > > On Wed, Oct 15, 2014 at 03:25:27PM +0800, Jason Wang wrote: > > > > Accumulate the sent packets and sent bytes in local variables and perform a > > > > single u64_stats_update_begin/end() after. > > > > > > >

From: Michael S. Tsirkin > On Wed, Oct 15, 2014 at 09:49:01AM +0000, David Laight wrote: > > From: Of Michael S. Tsirkin > > > On Wed, Oct 15, 2014 at 03:25:27PM +0800, Jason Wang wrote: > > > > Accumulate the sent packets and sent bytes in local variables and perform a > > > > single u64_stats_update_begin/end() after. > > > > > > >

On Wed, Oct 15, 2014 at 09:49:01AM +0000, David Laight wrote: > From: Of Michael S. Tsirkin > > On Wed, Oct 15, 2014 at 03:25:27PM +0800, Jason Wang wrote: > > > Accumulate the sent packets and sent bytes in local variables and perform a > > > single u64_stats_update_begin/end() after. > > > > > > Cc: Rusty Russell <rusty at rustcorp.com.au> >

On Wed, Oct 15, 2014 at 06:25:25PM +0800, Jason Wang wrote: > On 10/15/2014 06:18 PM, Michael S. Tsirkin wrote: > > On Wed, Oct 15, 2014 at 03:25:29PM +0800, Jason Wang wrote: > >> > Orphan skb in ndo_start_xmit() breaks socket accounting and packet > >> > queuing. This in fact breaks lots of things such as pktgen and several > >> > TCP optimizations.

On Wed, Oct 15, 2014 at 03:25:27PM +0800, Jason Wang wrote: > Accumulate the sent packets and sent bytes in local variables and perform a > single u64_stats_update_begin/end() after. > > Cc: Rusty Russell <rusty at rustcorp.com.au> > Cc: Michael S. Tsirkin <mst at redhat.com> > Signed-off-by: Jason Wang <jasowang at redhat.com> Not sure how much it's worth

From: Jason Wang <jasowang at redhat.com> We already have counters for sent packets and sent bytes. Use them to reduce the number of u64_stats_update_begin/end(). Take care not to bother with stats update when called speculatively. Based on a patch by Jason Wang. Cc: Rusty Russell <rusty at rustcorp.com.au> Signed-off-by: Jason Wang <jasowang at redhat.com> Signed-off-by:

From: Jason Wang <jasowang at redhat.com> We already have counters for sent packets and sent bytes. Use them to reduce the number of u64_stats_update_begin/end(). Take care not to bother with stats update when called speculatively. Based on a patch by Jason Wang. Cc: Rusty Russell <rusty at rustcorp.com.au> Signed-off-by: Jason Wang <jasowang at redhat.com> Signed-off-by:

From: Jason Wang <jasowang at redhat.com> We already have counters for sent packets and sent bytes. Use them to reduce the number of u64_stats_update_begin/end(). Take care not to bother with stats update when called speculatively. Based on a patch by Jason Wang. Cc: Rusty Russell <rusty at rustcorp.com.au> Signed-off-by: Jason Wang <jasowang at redhat.com> Signed-off-by: