virtio_net: reduce raw_smp_processor_id() calling in virtnet_xdp_get_sq

smp_processor_id()/raw* will be called once each when not
more queues in virtnet_xdp_get_sq() which is called in
non-preemptible context, so it's safe to call the function
smp_processor_id() once.

Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index b4ae2ac..271d38c 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -528,19 +528,20 @@ static int __virtnet_xdp_xmit_one(struct virtnet_info *vi,
  * functions to perfectly solve these three problems at the same time.
  */
 #define virtnet_xdp_get_sq(vi) ({                                       \
+       int cpu = smp_processor_id();                                   \
        struct netdev_queue *txq;                                       \
        typeof(vi) v = (vi);                                            \
        unsigned int qp;                                                \
                                                                        \
        if (v->curr_queue_pairs > nr_cpu_ids) {                         \
                qp = v->curr_queue_pairs - v->xdp_queue_pairs;          \
-               qp += smp_processor_id();                               \
+               qp += cpu;                                              \
                txq = netdev_get_tx_queue(v->dev, qp);                  \
                __netif_tx_acquire(txq);                                \
        } else {                                                        \
-               qp = smp_processor_id() % v->curr_queue_pairs;          \
+               qp = cpu % v->curr_queue_pairs;                         \
                txq = netdev_get_tx_queue(v->dev, qp);                  \
-               __netif_tx_lock(txq, raw_smp_processor_id());           \
+               __netif_tx_lock(txq, cpu);                              \
        }                                                               \
        v->sq + qp;                                                     \
 })