diff mbox series

[ovs-dev,PATCHv3] netdev-afxdp: Add interrupt mode netdev class.

Message ID 1582837038-31955-1-git-send-email-u9012063@gmail.com
State Changes Requested
Headers show
Series [ovs-dev,PATCHv3] netdev-afxdp: Add interrupt mode netdev class. | expand

Commit Message

William Tu Feb. 27, 2020, 8:57 p.m. UTC 
The patch adds a new netdev class 'afxdp-nonpmd' to enable afxdp
interrupt mode. This is similar to 'type=afxdp', except that the
is_pmd field is set to false. As a result, the packet processing
is handled by main thread, not pmd thread. This avoids burning
the CPU to always 100% when there is no traffic.

Tested-at: https://travis-ci.org/williamtu/ovs-travis/builds/655885506
Signed-off-by: William Tu <u9012063@gmail.com>
---
 NEWS                  |  3 +++
 lib/netdev-afxdp.c    |  2 +-
 lib/netdev-linux.c    | 20 ++++++++++++++++++++
 lib/netdev-provider.h |  1 +
 lib/netdev.c          |  1 +
 tests/system-afxdp.at | 23 +++++++++++++++++++++++
 6 files changed, 49 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/NEWS b/NEWS
index f62ef1f47ea8..594c55dc11d6 100644
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,9 @@  Post-v2.13.0
    - OpenFlow:
      * The OpenFlow ofp_desc/serial_num may now be configured by setting the
        value of other-config:dp-sn in the Bridge table.
+   - AF_XDP:
+     * New netdev class 'afxdp-nonpmd' for netdev-afxdp to save CPU cycles
+       by enabling interrupt mode.
 
 
 v2.13.0 - 14 Feb 2020
diff --git a/lib/netdev-afxdp.c b/lib/netdev-afxdp.c
index 482400d8d135..b806a6344e1e 100644
--- a/lib/netdev-afxdp.c
+++ b/lib/netdev-afxdp.c
@@ -1115,9 +1115,9 @@  netdev_afxdp_batch_send(struct netdev *netdev, int qid,
     struct netdev_linux *dev;
     int ret;
 
+    qid = qid % netdev_n_txq(netdev);
     if (concurrent_txq) {
         dev = netdev_linux_cast(netdev);
-        qid = qid % netdev_n_txq(netdev);
 
         ovs_spin_lock(&dev->tx_locks[qid].lock);
         ret = __netdev_afxdp_batch_send(netdev, qid, batch);
diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index c6f3d27409b6..75b3b55d3cad 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -3605,6 +3605,26 @@  const struct netdev_class netdev_afxdp_class = {
     .rxq_destruct = netdev_afxdp_rxq_destruct,
     .rxq_recv = netdev_afxdp_rxq_recv,
 };
+
+const struct netdev_class netdev_afxdp_nonpmd_class = {
+    NETDEV_LINUX_CLASS_COMMON,
+    .type = "afxdp-nonpmd",
+    .is_pmd = false,
+    .init = netdev_afxdp_init,
+    .construct = netdev_afxdp_construct,
+    .destruct = netdev_afxdp_destruct,
+    .get_stats = netdev_afxdp_get_stats,
+    .get_custom_stats = netdev_afxdp_get_custom_stats,
+    .get_status = netdev_linux_get_status,
+    .set_config = netdev_afxdp_set_config,
+    .get_config = netdev_afxdp_get_config,
+    .reconfigure = netdev_afxdp_reconfigure,
+    .get_numa_id = netdev_linux_get_numa_id,
+    .send = netdev_afxdp_batch_send,
+    .rxq_construct = netdev_afxdp_rxq_construct,
+    .rxq_destruct = netdev_afxdp_rxq_destruct,
+    .rxq_recv = netdev_afxdp_rxq_recv,
+};
 #endif
 
 
diff --git a/lib/netdev-provider.h b/lib/netdev-provider.h
index 22f4cde3337a..06c1d98a0b07 100644
--- a/lib/netdev-provider.h
+++ b/lib/netdev-provider.h
@@ -848,6 +848,7 @@  extern const struct netdev_class netdev_tap_class;
 
 #ifdef HAVE_AF_XDP
 extern const struct netdev_class netdev_afxdp_class;
+extern const struct netdev_class netdev_afxdp_nonpmd_class;
 #endif
 #ifdef  __cplusplus
 }
diff --git a/lib/netdev.c b/lib/netdev.c
index f95b19af4da0..6d9723ebc3c1 100644
--- a/lib/netdev.c
+++ b/lib/netdev.c
@@ -154,6 +154,7 @@  netdev_initialize(void)
         netdev_register_flow_api_provider(&netdev_offload_tc);
 #ifdef HAVE_AF_XDP
         netdev_register_provider(&netdev_afxdp_class);
+        netdev_register_provider(&netdev_afxdp_nonpmd_class);
 #endif
 #endif
 #if defined(__FreeBSD__) || defined(__NetBSD__)
diff --git a/tests/system-afxdp.at b/tests/system-afxdp.at
index e4451624f882..0d09906fb6c8 100644
--- a/tests/system-afxdp.at
+++ b/tests/system-afxdp.at
@@ -22,3 +22,26 @@  AT_CHECK([grep "ovs-p0: could not set configuration" ovs-vswitchd.log | wc -l],
 OVS_TRAFFIC_VSWITCHD_STOP(["/ovs-p0: Too big 'n_rxq'/d
 /ovs-p0: could not set configuration/d"])
 AT_CLEANUP
+
+
+AT_SETUP([AF_XDP - ping between pmd and non-pmd ports])
+AT_KEYWORDS([afxdp nonpmd])
+OVS_TRAFFIC_VSWITCHD_START()
+
+AT_CHECK([ovs-ofctl add-flow br0 "actions=normal"])
+
+ADD_NAMESPACES(at_ns0, at_ns1)
+ADD_VETH(p0, at_ns0, br0, "10.1.1.1/24")
+ADD_VETH(p1, at_ns1, br0, "10.1.1.2/24")
+
+AT_CHECK([ovs-vsctl del-port ovs-p0])
+AT_CHECK([ovs-vsctl add-port br0 ovs-p0 -- \
+                    set interface ovs-p0 type=afxdp-nonpmd options:n_rxq=1],
+         [0], [], [stderr])
+
+NS_CHECK_EXEC([at_ns0], [ping -q -c 3 -i 0.3 -w 2 10.1.1.2 | FORMAT_PING], [0], [dnl
+3 packets transmitted, 3 received, 0% packet loss, time 0ms
+])
+
+OVS_TRAFFIC_VSWITCHD_STOP
+AT_CLEANUP