Tue, Jun 18, 2024 at 02:53:42AM CEST, jasow...@redhat.com wrote: >On Mon, Jun 17, 2024 at 5:18 PM Jiri Pirko <j...@resnulli.us> wrote: >> >> Mon, Jun 17, 2024 at 04:34:26AM CEST, jasow...@redhat.com wrote: >> >On Thu, Jun 13, 2024 at 1:09 AM Jiri Pirko <j...@resnulli.us> wrote: >> >> >> >> From: Jiri Pirko <j...@nvidia.com> >> >> >> >> Add support for Byte Queue Limits (BQL). >> >> >> >> Tested on qemu emulated virtio_net device with 1, 2 and 4 queues. >> >> Tested with fq_codel and pfifo_fast. Super netperf with 50 threads is >> >> running in background. Netperf TCP_RR results: >> >> >> >> NOBQL FQC 1q: 159.56 159.33 158.50 154.31 agv: 157.925 >> >> NOBQL FQC 2q: 184.64 184.96 174.73 174.15 agv: 179.62 >> >> NOBQL FQC 4q: 994.46 441.96 416.50 499.56 agv: 588.12 >> >> NOBQL PFF 1q: 148.68 148.92 145.95 149.48 agv: 148.2575 >> >> NOBQL PFF 2q: 171.86 171.20 170.42 169.42 agv: 170.725 >> >> NOBQL PFF 4q: 1505.23 1137.23 2488.70 3507.99 agv: 2159.7875 >> >> BQL FQC 1q: 1332.80 1297.97 1351.41 1147.57 agv: 1282.4375 >> >> BQL FQC 2q: 768.30 817.72 864.43 974.40 agv: 856.2125 >> >> BQL FQC 4q: 945.66 942.68 878.51 822.82 agv: 897.4175 >> >> BQL PFF 1q: 149.69 151.49 149.40 147.47 agv: 149.5125 >> >> BQL PFF 2q: 2059.32 798.74 1844.12 381.80 agv: 1270.995 >> >> BQL PFF 4q: 1871.98 4420.02 4916.59 13268.16 agv: 6119.1875 >> >> >> >> Signed-off-by: Jiri Pirko <j...@nvidia.com> >> >> --- >> >> v1->v2: >> >> - moved netdev_tx_completed_queue() call into __free_old_xmit(), >> >> propagate use_napi flag to __free_old_xmit() and only call >> >> netdev_tx_completed_queue() in case it is true >> >> - added forgotten call to netdev_tx_reset_queue() >> >> - fixed stats for xdp packets >> >> - fixed bql accounting when __free_old_xmit() is called from xdp path >> >> - handle the !use_napi case in start_xmit() kick section >> >> --- >> >> drivers/net/virtio_net.c | 50 +++++++++++++++++++++++++--------------- >> >> 1 file changed, 32 insertions(+), 18 deletions(-) >> >> >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> >> index 61a57d134544..5863c663ccab 100644 >> >> --- a/drivers/net/virtio_net.c >> >> +++ b/drivers/net/virtio_net.c >> >> @@ -84,7 +84,9 @@ struct virtnet_stat_desc { >> >> >> >> struct virtnet_sq_free_stats { >> >> u64 packets; >> >> + u64 xdp_packets; >> >> u64 bytes; >> >> + u64 xdp_bytes; >> >> }; >> >> >> >> struct virtnet_sq_stats { >> >> @@ -506,29 +508,33 @@ static struct xdp_frame *ptr_to_xdp(void *ptr) >> >> return (struct xdp_frame *)((unsigned long)ptr & >> >> ~VIRTIO_XDP_FLAG); >> >> } >> >> >> >> -static void __free_old_xmit(struct send_queue *sq, bool in_napi, >> >> +static void __free_old_xmit(struct send_queue *sq, struct netdev_queue >> >> *txq, >> >> + bool in_napi, bool use_napi, >> >> struct virtnet_sq_free_stats *stats) >> >> { >> >> unsigned int len; >> >> void *ptr; >> >> >> >> while ((ptr = virtqueue_get_buf(sq->vq, &len)) != NULL) { >> >> - ++stats->packets; >> >> - >> >> if (!is_xdp_frame(ptr)) { >> >> struct sk_buff *skb = ptr; >> >> >> >> pr_debug("Sent skb %p\n", skb); >> >> >> >> + stats->packets++; >> >> stats->bytes += skb->len; >> >> napi_consume_skb(skb, in_napi); >> >> } else { >> >> struct xdp_frame *frame = ptr_to_xdp(ptr); >> >> >> >> - stats->bytes += xdp_get_frame_len(frame); >> >> + stats->xdp_packets++; >> >> + stats->xdp_bytes += xdp_get_frame_len(frame); >> >> xdp_return_frame(frame); >> >> } >> >> } >> >> + if (use_napi) >> >> + netdev_tx_completed_queue(txq, stats->packets, >> >> stats->bytes); >> >> + >> >> } >> > >> >I wonder if this works correctly, for example NAPI could be enabled >> >after queued but before sent. So __netdev_tx_sent_queue() is not >> >called before. >> >> How is that possible? Napi weight can't change when link is up. Or am I >> missing something? > >Something like this: > >1) packet were queued >2) if down >3) enable NAPI >4) if up >5) packet were sent
Gotcha, will try to fix. Thanks! > >? > >Thanks > >> >> > >> >Thanks >> > >> >