| Message ID | 1461640422-20779-1-git-send-email-jasowang@redhat.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Jason Wang <jasowang@redhat.com> Date: Mon, 25 Apr 2016 23:13:42 -0400 > There's no need to calculate rps hash if it was not enabled. So this > patch export rps_needed and check it before trying to get rps > hash. Tests (using pktgen to inject packets to guest) shows this can > improve pps about 13% (when rps is disabled). > > Before: > ~1150000 pps > After: > ~1300000 pps > > Cc: Michael S. Tsirkin <mst@redhat.com> > Signed-off-by: Jason Wang <jasowang@redhat.com> Applied, thanks Jason.
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index afdf950..8df9e23 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -819,7 +819,8 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) if (txq >= numqueues) goto drop; - if (numqueues == 1) { +#ifdef CONFIG_RPS + if (numqueues == 1 && static_key_false(&rps_needed)) { /* Select queue was not called for the skbuff, so we extract the * RPS hash and save it into the flow_table here. */ @@ -834,6 +835,7 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) tun_flow_save_rps_rxhash(e, rxhash); } } +#endif tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len); diff --git a/net/core/dev.c b/net/core/dev.c index b9bcbe7..d4ba936 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3428,6 +3428,7 @@ u32 rps_cpu_mask __read_mostly; EXPORT_SYMBOL(rps_cpu_mask); struct static_key rps_needed __read_mostly; +EXPORT_SYMBOL(rps_needed); static struct rps_dev_flow * set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
There's no need to calculate rps hash if it was not enabled. So this patch export rps_needed and check it before trying to get rps hash. Tests (using pktgen to inject packets to guest) shows this can improve pps about 13% (when rps is disabled). Before: ~1150000 pps After: ~1300000 pps Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> ---- Changes from V1: - Fix build when CONFIG_RPS is not set --- drivers/net/tun.c | 4 +++- net/core/dev.c | 1 + 2 files changed, 4 insertions(+), 1 deletion(-)