netdev-dpdk: Track vhost tx contention.
Add a coverage counter to help diagnose contention on the vhost txqs.
This is seen as dropped packets on the physical ports for rates that
are usually handled fine by OVS.
Acked-by: Eelco Chaudron
#include <rte_vhost.h>
#include "cmap.h"
+#include "coverage.h"
#include "dirs.h"
#include "dp-packet.h"
#include "dpdk.h"
@@ -72,6 +73,8 @@ enum {VIRTIO_RXQ, VIRTIO_TXQ, VIRTIO_QNUM};
VLOG_DEFINE_THIS_MODULE(netdev_dpdk);
static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
+COVERAGE_DEFINE(vhost_tx_contention);
+
#define DPDK_PORT_WATCHDOG_INTERVAL 5
#define OVS_CACHE_LINE_SIZE CACHE_LINE_SIZE
@@ -2376,7 +2379,10 @@ __netdev_dpdk_vhost_send(struct netdev *netdev, int qid,
goto out;
}
+ if (OVS_UNLIKELY(!rte_spinlock_trylock(&dev->tx_q[qid].tx_lock))) {
+ COVERAGE_INC(vhost_tx_contention);
rte_spinlock_lock(&dev->tx_q[qid].tx_lock);
+ }
cnt = netdev_dpdk_filter_packet_len(dev, cur_pkts, cnt);
/* Check has QoS has been configured for the netdev */
