[ovs-dev] 答复: [openvswitch.org代发] [PATCH v2] netdev-afxdp: Best-effort configuration of XDP mode.

diff --git a/Documentation/intro/install/afxdp.rst
b/Documentation/intro/install/afxdp.rst
index a136db0c9..937770ad0 100644
--- a/Documentation/intro/install/afxdp.rst
+++ b/Documentation/intro/install/afxdp.rst
@@ -153,9 +153,8 @@  To kick start end-to-end autotesting::
   make check-afxdp TESTSUITEFLAGS='1'
 
 .. note::
-   Not all test cases pass at this time. Currenly all TCP related
-   tests, ex: using wget or http, are skipped due to XDP limitations
-   on veth. cvlan test is also skipped.
+   Not all test cases pass at this time. Currenly all cvlan tests are
skipped
+   due to kernel issues.
 
 If a test case fails, check the log at::
 
@@ -177,33 +176,35 @@  in :doc:`general`::
   ovs-vsctl -- add-br br0 -- set Bridge br0 datapath_type=netdev
 
 Make sure your device driver support AF_XDP, netdev-afxdp supports -the
following additional options (see man ovs-vswitchd.conf.db for
+the following additional options (see ``man ovs-vswitchd.conf.db`` for
 more details):
 
- * **xdpmode**: use "drv" for driver mode, or "skb" for skb mode.
+ * ``xdp-mode``: ``best-effort``, ``native-with-zerocopy``,
+   ``native`` or ``generic``.  Defaults to ``best-effort``, i.e. best of
+   supported modes, so in most cases you don't need to change it.
 
- * **use-need-wakeup**: default "true" if libbpf supports it, otherwise
false.
+ * ``use-need-wakeup``: default ``true`` if libbpf supports it,
+   otherwise ``false``.
 
 For example, to use 1 PMD (on core 4) on 1 queue (queue 0) device,
-configure these options: **pmd-cpu-mask, pmd-rxq-affinity, and n_rxq**.
-The **xdpmode** can be "drv" or "skb"::
+configure these options: ``pmd-cpu-mask``, ``pmd-rxq-affinity``, and
+``n_rxq``::
 
   ethtool -L enp2s0 combined 1
   ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=0x10
   ovs-vsctl add-port br0 enp2s0 -- set interface enp2s0 type="afxdp" \
-    options:n_rxq=1 options:xdpmode=drv \
-    other_config:pmd-rxq-affinity="0:4"
+                                   other_config:pmd-rxq-affinity="0:4"
 
 Or, use 4 pmds/cores and 4 queues by doing::
 
   ethtool -L enp2s0 combined 4
   ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=0x36
   ovs-vsctl add-port br0 enp2s0 -- set interface enp2s0 type="afxdp" \
-    options:n_rxq=4 options:xdpmode=drv \
-    other_config:pmd-rxq-affinity="0:1,1:2,2:3,3:4"
+    options:n_rxq=4 other_config:pmd-rxq-affinity="0:1,1:2,2:3,3:4"
 
 .. note::
-   pmd-rxq-affinity is optional. If not specified, system will auto-assign.
+   ``pmd-rxq-affinity`` is optional. If not specified, system will
auto-assign.
+   ``n_rxq`` equals ``1`` by default.
 
 To validate that the bridge has successfully instantiated, you can use
the::
 
@@ -214,12 +215,21 @@  Should show something like::
   Port "ens802f0"
    Interface "ens802f0"
       type: afxdp
-      options: {n_rxq="1", xdpmode=drv}
+      options: {n_rxq="1"}
 
 Otherwise, enable debugging by::
 
   ovs-appctl vlog/set netdev_afxdp::dbg
 
+To check which XDP mode was chosen by ``best-effort``, you can look for 
+``xdp-mode-in-use`` in the output of ``ovs-appctl dpctl/show``::
+
+  # ovs-appctl dpctl/show
+  netdev@ovs-netdev:
+    <...>
+    port 2: ens802f0 (afxdp: n_rxq=1, use-need-wakeup=true,
+                      xdp-mode=best-effort,
+                      xdp-mode-in-use=native-with-zerocopy)
 
 References
 ----------
@@ -323,8 +333,11 @@  Limitations/Known Issues  #. Most of the tests are done
using i40e single port. Multiple ports and
    also ixgbe driver also needs to be tested.
 #. No latency test result (TODO items)
-#. Due to limitations of current upstream kernel, TCP and various
offloading
+#. Due to limitations of current upstream kernel, various offloading
    (vlan, cvlan) is not working over virtual interfaces (i.e. veth pair).
+   Also, TCP is not working over virtual interfaces in generic XDP mode.
+   Some more information and possible workaround available `here
+   <https://github.com/cilium/cilium/issues/3077#issuecomment-430801467>`__
.
 
 
 PVP using tap device
@@ -335,8 +348,7 @@  First, start OVS, then add physical port::
   ethtool -L enp2s0 combined 1
   ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=0x10
   ovs-vsctl add-port br0 enp2s0 -- set interface enp2s0 type="afxdp" \
-    options:n_rxq=1 options:xdpmode=drv \
-    other_config:pmd-rxq-affinity="0:4"
+    options:n_rxq=1 other_config:pmd-rxq-affinity="0:4"
 
 Start a VM with virtio and tap device::
 
@@ -414,13 +426,11 @@  Create namespace and veth peer devices::
 
 Attach the veth port to br0 (linux kernel mode)::
 
-  ovs-vsctl add-port br0 afxdp-p0 -- \
-    set interface afxdp-p0 options:n_rxq=1
+  ovs-vsctl add-port br0 afxdp-p0 -- set interface afxdp-p0
 
-Or, use AF_XDP with skb mode::
+Or, use AF_XDP::
 
-  ovs-vsctl add-port br0 afxdp-p0 -- \
-    set interface afxdp-p0 type="afxdp" options:n_rxq=1 options:xdpmode=skb
+  ovs-vsctl add-port br0 afxdp-p0 -- set interface afxdp-p0 type="afxdp"
 
 Setup the OpenFlow rules::
 
diff --git a/NEWS b/NEWS
index 88b818948..d5f476d6e 100644
--- a/NEWS
+++ b/NEWS
@@ -5,11 +5,19 @@  Post-v2.12.0
        separate project. You can find it at
        https://github.com/ovn-org/ovn.git
    - Userspace datapath:
+     * Add option to enable, disable and query TCP sequence checking in
+       conntrack.
+   - AF_XDP:
      * New option 'use-need-wakeup' for netdev-afxdp to control enabling
        of corresponding 'need_wakeup' flag in AF_XDP rings.  Enabled by
default
        if supported by libbpf.
-     * Add option to enable, disable and query TCP sequence checking in
-       conntrack.
+     * 'xdpmode' option for netdev-afxdp renamed to 'xdp-mode'.
+       Modes also updated.  New values:
+         native-with-zerocopy  - former DRV
+         native                - new one, DRV without zero-copy
+         generic               - former SKB
+         best-effort [default] - new one, chooses the best available from
+                                 3 above modes
 
 v2.12.0 - 03 Sep 2019
 ---------------------
diff --git a/lib/netdev-afxdp.c b/lib/netdev-afxdp.c index
af654d498..74dde219d 100644
--- a/lib/netdev-afxdp.c
+++ b/lib/netdev-afxdp.c
@@ -89,12 +89,42 @@  BUILD_ASSERT_DECL(PROD_NUM_DESCS == CONS_NUM_DESCS);
#define UMEM2DESC(elem, base) ((uint64_t)((char *)elem - (char *)base))
 
 static struct xsk_socket_info *xsk_configure(int ifindex, int xdp_queue_id,
-                                             int mode, bool
use_need_wakeup);
-static void xsk_remove_xdp_program(uint32_t ifindex, int xdpmode);
+                                             enum afxdp_mode mode,
+                                             bool use_need_wakeup,
+                                             bool 
+report_socket_failures); static void xsk_remove_xdp_program(uint32_t 
+ifindex, enum afxdp_mode);
 static void xsk_destroy(struct xsk_socket_info *xsk);  static int
xsk_configure_all(struct netdev *netdev);  static void
xsk_destroy_all(struct netdev *netdev);
 
+static struct {
+    const char *name;
+    uint32_t bind_flags;
+    uint32_t xdp_flags;
+} xdp_modes[] = {
+    [OVS_AF_XDP_MODE_UNSPEC] = {
+        .name = "unspecified", .bind_flags = 0, .xdp_flags = 0,
+    },
+    [OVS_AF_XDP_MODE_BEST_EFFORT] = {
+        .name = "best-effort", .bind_flags = 0, .xdp_flags = 0,
+    },
+    [OVS_AF_XDP_MODE_NATIVE_ZC] = {
+        .name = "native-with-zerocopy",
+        .bind_flags = XDP_ZEROCOPY,
+        .xdp_flags = XDP_FLAGS_DRV_MODE,
+    },
+    [OVS_AF_XDP_MODE_NATIVE] = {
+        .name = "native",
+        .bind_flags = XDP_COPY,
+        .xdp_flags = XDP_FLAGS_DRV_MODE,
+    },
+    [OVS_AF_XDP_MODE_GENERIC] = {
+        .name = "generic",
+        .bind_flags = XDP_COPY,
+        .xdp_flags = XDP_FLAGS_SKB_MODE,
+    },
+};
+
 struct unused_pool {
     struct xsk_umem_info *umem_info;
     int lost_in_rings; /* Number of packets left in tx, rx, cq and fq. */
@@ -214,7 +244,7 @@  netdev_afxdp_sweep_unused_pools(void *aux OVS_UNUSED)  }
 
 static struct xsk_umem_info *
-xsk_configure_umem(void *buffer, uint64_t size, int xdpmode)
+xsk_configure_umem(void *buffer, uint64_t size)
 {
     struct xsk_umem_config uconfig;
     struct xsk_umem_info *umem;
@@ -232,9 +262,7 @@  xsk_configure_umem(void *buffer, uint64_t size, int
xdpmode)
     ret = xsk_umem__create(&umem->umem, buffer, size, &umem->fq, &umem->cq,
                            &uconfig);
     if (ret) {
-        VLOG_ERR("xsk_umem__create failed (%s) mode: %s",
-                 ovs_strerror(errno),
-                 xdpmode == XDP_COPY ? "SKB": "DRV");
+        VLOG_ERR("xsk_umem__create failed: %s.", ovs_strerror(errno));
         free(umem);
         return NULL;
     }
@@ -290,7 +318,8 @@  xsk_configure_umem(void *buffer, uint64_t size, int
xdpmode)
 
 static struct xsk_socket_info *
 xsk_configure_socket(struct xsk_umem_info *umem, uint32_t ifindex,
-                     uint32_t queue_id, int xdpmode, bool use_need_wakeup)
+                     uint32_t queue_id, enum afxdp_mode mode,
+                     bool use_need_wakeup, bool report_socket_failures)
 {
     struct xsk_socket_config cfg;
     struct xsk_socket_info *xsk;
@@ -304,14 +333,8 @@  xsk_configure_socket(struct xsk_umem_info *umem,
uint32_t ifindex,
     cfg.rx_size = CONS_NUM_DESCS;
     cfg.tx_size = PROD_NUM_DESCS;
     cfg.libbpf_flags = 0;
-
-    if (xdpmode == XDP_ZEROCOPY) {
-        cfg.bind_flags = XDP_ZEROCOPY;
-        cfg.xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST | XDP_FLAGS_DRV_MODE;
-    } else {
-        cfg.bind_flags = XDP_COPY;
-        cfg.xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST | XDP_FLAGS_SKB_MODE;
-    }
+    cfg.bind_flags = xdp_modes[mode].bind_flags;
+    cfg.xdp_flags = xdp_modes[mode].xdp_flags | 
+ XDP_FLAGS_UPDATE_IF_NOEXIST;
 
 #ifdef HAVE_XDP_NEED_WAKEUP
     if (use_need_wakeup) {
@@ -329,12 +352,11 @@  xsk_configure_socket(struct xsk_umem_info *umem,
uint32_t ifindex,
     ret = xsk_socket__create(&xsk->xsk, devname, queue_id, umem->umem,
                              &xsk->rx, &xsk->tx, &cfg);
     if (ret) {
-        VLOG_ERR("xsk_socket__create failed (%s) mode: %s "
-                 "use-need-wakeup: %s qid: %d",
-                 ovs_strerror(errno),
-                 xdpmode == XDP_COPY ? "SKB": "DRV",
-                 use_need_wakeup ? "true" : "false",
-                 queue_id);
+        VLOG(report_socket_failures ? VLL_ERR : VLL_DBG,
+             "xsk_socket__create failed (%s) mode: %s, "
+             "use-need-wakeup: %s, qid: %d",
+             ovs_strerror(errno), xdp_modes[mode].name,
+             use_need_wakeup ? "true" : "false", queue_id);
         free(xsk);
         return NULL;
     }
@@ -375,8 +397,8 @@  xsk_configure_socket(struct xsk_umem_info *umem,
uint32_t ifindex,  }
 
 static struct xsk_socket_info *
-xsk_configure(int ifindex, int xdp_queue_id, int xdpmode,
-              bool use_need_wakeup)
+xsk_configure(int ifindex, int xdp_queue_id, enum afxdp_mode mode,
+              bool use_need_wakeup, bool report_socket_failures)
 {
     struct xsk_socket_info *xsk;
     struct xsk_umem_info *umem;
@@ -389,9 +411,7 @@  xsk_configure(int ifindex, int xdp_queue_id, int
xdpmode,
     memset(bufs, 0, NUM_FRAMES * FRAME_SIZE);
 
     /* Create AF_XDP socket. */
-    umem = xsk_configure_umem(bufs,
-                              NUM_FRAMES * FRAME_SIZE,
-                              xdpmode);
+    umem = xsk_configure_umem(bufs, NUM_FRAMES * FRAME_SIZE);
     if (!umem) {
         free_pagealign(bufs);
         return NULL;
@@ -399,8 +419,8 @@  xsk_configure(int ifindex, int xdp_queue_id, int
xdpmode,
 
     VLOG_DBG("Allocated umem pool at 0x%"PRIxPTR, (uintptr_t) umem);
 
-    xsk = xsk_configure_socket(umem, ifindex, xdp_queue_id, xdpmode,
-                               use_need_wakeup);
+    xsk = xsk_configure_socket(umem, ifindex, xdp_queue_id, mode,
+                               use_need_wakeup, 
+ report_socket_failures);
     if (!xsk) {
         /* Clean up umem and xpacket pool. */
         if (xsk_umem__delete(umem->umem)) { @@ -414,12 +434,38 @@
xsk_configure(int ifindex, int xdp_queue_id, int xdpmode,
     return xsk;
 }
 
+static int
+xsk_configure_queue(struct netdev_linux *dev, int ifindex, int queue_id,
+                    enum afxdp_mode mode, bool report_socket_failures) 
+{
+    struct xsk_socket_info *xsk_info;
+
+    VLOG_DBG("%s: configuring queue: %d, mode: %s, use-need-wakeup: %s.",
+             netdev_get_name(&dev->up), queue_id, xdp_modes[mode].name,
+             dev->use_need_wakeup ? "true" : "false");
+    xsk_info = xsk_configure(ifindex, queue_id, mode, dev->use_need_wakeup,
+                             report_socket_failures);
+    if (!xsk_info) {
+        VLOG(report_socket_failures ? VLL_ERR : VLL_DBG,
+             "%s: Failed to create AF_XDP socket on queue %d in %s mode.",
+             netdev_get_name(&dev->up), queue_id, xdp_modes[mode].name);
+        dev->xsks[queue_id] = NULL;
+        return -1;
+    }
+    dev->xsks[queue_id] = xsk_info;
+    atomic_init(&xsk_info->tx_dropped, 0);
+    xsk_info->outstanding_tx = 0;
+    xsk_info->available_rx = PROD_NUM_DESCS;
+    return 0;
+}
+
+
 static int
 xsk_configure_all(struct netdev *netdev)  {
     struct netdev_linux *dev = netdev_linux_cast(netdev);
-    struct xsk_socket_info *xsk_info;
     int i, ifindex, n_rxq, n_txq;
+    int qid = 0;
 
     ifindex = linux_get_ifindex(netdev_get_name(netdev));
 
@@ -429,23 +475,36 @@  xsk_configure_all(struct netdev *netdev)
     n_rxq = netdev_n_rxq(netdev);
     dev->xsks = xcalloc(n_rxq, sizeof *dev->xsks);
 
-    /* Configure each queue. */
-    for (i = 0; i < n_rxq; i++) {
-        VLOG_DBG("%s: configure queue %d mode %s use-need-wakeup %s.",
-                 netdev_get_name(netdev), i,
-                 dev->xdpmode == XDP_COPY ? "SKB" : "DRV",
-                 dev->use_need_wakeup ? "true" : "false");
-        xsk_info = xsk_configure(ifindex, i, dev->xdpmode,
-                                 dev->use_need_wakeup);
-        if (!xsk_info) {
-            VLOG_ERR("Failed to create AF_XDP socket on queue %d.", i);
-            dev->xsks[i] = NULL;
+    if (dev->xdp_mode == OVS_AF_XDP_MODE_BEST_EFFORT) {
+        /* Trying to configure first queue with different modes to
+         * find the most suitable. */
+        for (i = OVS_AF_XDP_MODE_NATIVE_ZC; i < OVS_AF_XDP_MODE_MAX; i++) {
+            if (!xsk_configure_queue(dev, ifindex, qid, i,
+                                     i == OVS_AF_XDP_MODE_MAX - 1)) {
+                dev->xdp_mode_in_use = i;
+                VLOG_INFO("%s: %s XDP mode will be in use.",
+                          netdev_get_name(netdev), xdp_modes[i].name);
+                break;
+            }
+        }
+        if (i == OVS_AF_XDP_MODE_MAX) {
+            VLOG_ERR("%s: Failed to detect suitable XDP mode.",
+                     netdev_get_name(netdev));
+            goto err;
+        }
+        qid++;
+    } else {
+        dev->xdp_mode_in_use = dev->xdp_mode;
+    }
+
+    /* Configure remaining queues. */
+    for (; qid < n_rxq; qid++) {
+        if (xsk_configure_queue(dev, ifindex, qid,
+                                dev->xdp_mode_in_use, true)) {
+            VLOG_ERR("%s: Failed to create AF_XDP socket on queue %d.",
+                     netdev_get_name(netdev), qid);
             goto err;
         }
-        dev->xsks[i] = xsk_info;
-        atomic_init(&xsk_info->tx_dropped, 0);
-        xsk_info->outstanding_tx = 0;
-        xsk_info->available_rx = PROD_NUM_DESCS;
     }
 
     n_txq = netdev_n_txq(netdev);
@@ -500,7 +559,7 @@  xsk_destroy_all(struct netdev *netdev)
             if (dev->xsks[i]) {
                 xsk_destroy(dev->xsks[i]);
                 dev->xsks[i] = NULL;
-                VLOG_INFO("Destroyed xsk[%d].", i);
+                VLOG_DBG("%s: Destroyed xsk[%d].", 
+ netdev_get_name(netdev), i);
             }
         }
 
@@ -510,7 +569,7 @@  xsk_destroy_all(struct netdev *netdev)
 
     VLOG_INFO("%s: Removing xdp program.", netdev_get_name(netdev));
     ifindex = linux_get_ifindex(netdev_get_name(netdev));
-    xsk_remove_xdp_program(ifindex, dev->xdpmode);
+    xsk_remove_xdp_program(ifindex, dev->xdp_mode_in_use);
 
     if (dev->tx_locks) {
         for (i = 0; i < netdev_n_txq(netdev); i++) { @@ -526,9 +585,10 @@
netdev_afxdp_set_config(struct netdev *netdev, const struct smap *args,
                         char **errp OVS_UNUSED)  {
     struct netdev_linux *dev = netdev_linux_cast(netdev);
-    const char *str_xdpmode;
-    int xdpmode, new_n_rxq;
+    const char *str_xdp_mode;
+    enum afxdp_mode xdp_mode;
     bool need_wakeup;
+    int new_n_rxq;
 
     ovs_mutex_lock(&dev->mutex);
     new_n_rxq = MAX(smap_get_int(args, "n_rxq", NR_QUEUE), 1); @@ -539,14
+599,17 @@ netdev_afxdp_set_config(struct netdev *netdev, const struct smap
*args,
         return EINVAL;
     }
 
-    str_xdpmode = smap_get_def(args, "xdpmode", "skb");
-    if (!strcasecmp(str_xdpmode, "drv")) {
-        xdpmode = XDP_ZEROCOPY;
-    } else if (!strcasecmp(str_xdpmode, "skb")) {
-        xdpmode = XDP_COPY;
-    } else {
-        VLOG_ERR("%s: Incorrect xdpmode (%s).",
-                 netdev_get_name(netdev), str_xdpmode);
+    str_xdp_mode = smap_get_def(args, "xdp-mode", "best-effort");
+    for (xdp_mode = OVS_AF_XDP_MODE_BEST_EFFORT;
+         xdp_mode < OVS_AF_XDP_MODE_MAX;
+         xdp_mode++) {
+        if (!strcasecmp(str_xdp_mode, xdp_modes[xdp_mode].name)) {
+            break;
+        }
+    }
+    if (xdp_mode == OVS_AF_XDP_MODE_MAX) {
+        VLOG_ERR("%s: Incorrect xdp-mode (%s).",
+                 netdev_get_name(netdev), str_xdp_mode);
         ovs_mutex_unlock(&dev->mutex);
         return EINVAL;
     }
@@ -560,10 +623,10 @@  netdev_afxdp_set_config(struct netdev *netdev, const
struct smap *args,  #endif
 
     if (dev->requested_n_rxq != new_n_rxq
-        || dev->requested_xdpmode != xdpmode
+        || dev->requested_xdp_mode != xdp_mode
         || dev->requested_need_wakeup != need_wakeup) {
         dev->requested_n_rxq = new_n_rxq;
-        dev->requested_xdpmode = xdpmode;
+        dev->requested_xdp_mode = xdp_mode;
         dev->requested_need_wakeup = need_wakeup;
         netdev_request_reconfigure(netdev);
     }
@@ -578,8 +641,9 @@  netdev_afxdp_get_config(const struct netdev *netdev,
struct smap *args)
 
     ovs_mutex_lock(&dev->mutex);
     smap_add_format(args, "n_rxq", "%d", netdev->n_rxq);
-    smap_add_format(args, "xdpmode", "%s",
-                    dev->xdpmode == XDP_ZEROCOPY ? "drv" : "skb");
+    smap_add_format(args, "xdp-mode", "%s", xdp_modes[dev->xdp_mode].name);
+    smap_add_format(args, "xdp-mode-in-use", "%s",
+                    xdp_modes[dev->xdp_mode_in_use].name);
     smap_add_format(args, "use-need-wakeup", "%s",
                     dev->use_need_wakeup ? "true" : "false");
     ovs_mutex_unlock(&dev->mutex);
@@ -596,7 +660,7 @@  netdev_afxdp_reconfigure(struct netdev *netdev)
     ovs_mutex_lock(&dev->mutex);
 
     if (netdev->n_rxq == dev->requested_n_rxq
-        && dev->xdpmode == dev->requested_xdpmode
+        && dev->xdp_mode == dev->requested_xdp_mode
         && dev->use_need_wakeup == dev->requested_need_wakeup
         && dev->xsks) {
         goto out;
@@ -607,9 +671,9 @@  netdev_afxdp_reconfigure(struct netdev *netdev)
     netdev->n_rxq = dev->requested_n_rxq;
     netdev->n_txq = netdev->n_rxq;
 
-    dev->xdpmode = dev->requested_xdpmode;
+    dev->xdp_mode = dev->requested_xdp_mode;
     VLOG_INFO("%s: Setting XDP mode to %s.", netdev_get_name(netdev),
-              dev->xdpmode == XDP_ZEROCOPY ? "DRV" : "SKB");
+              xdp_modes[dev->xdp_mode].name);
 
     if (setrlimit(RLIMIT_MEMLOCK, &r)) {
         VLOG_ERR("setrlimit(RLIMIT_MEMLOCK) failed: %s",
ovs_strerror(errno)); @@ -618,7 +682,8 @@ netdev_afxdp_reconfigure(struct
netdev *netdev)
 
     err = xsk_configure_all(netdev);
     if (err) {
-        VLOG_ERR("AF_XDP device %s reconfig failed.",
netdev_get_name(netdev));
+        VLOG_ERR("%s: AF_XDP device reconfiguration failed.",
+                 netdev_get_name(netdev));
     }
     netdev_change_seq_changed(netdev);
 out:
@@ -638,17 +703,9 @@  netdev_afxdp_get_numa_id(const struct netdev *netdev)
}
 
 static void
-xsk_remove_xdp_program(uint32_t ifindex, int xdpmode)
+xsk_remove_xdp_program(uint32_t ifindex, enum afxdp_mode mode)
 {
-    uint32_t flags;
-
-    flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
-
-    if (xdpmode == XDP_COPY) {
-        flags |= XDP_FLAGS_SKB_MODE;
-    } else if (xdpmode == XDP_ZEROCOPY) {
-        flags |= XDP_FLAGS_DRV_MODE;
-    }
+    uint32_t flags = xdp_modes[mode].xdp_flags | 
+ XDP_FLAGS_UPDATE_IF_NOEXIST;
 
     bpf_set_link_xdp_fd(ifindex, -1, flags);  } @@ -662,7 +719,7 @@
signal_remove_xdp(struct netdev *netdev)
     ifindex = linux_get_ifindex(netdev_get_name(netdev));
 
     VLOG_WARN("Force removing xdp program.");
-    xsk_remove_xdp_program(ifindex, dev->xdpmode);
+    xsk_remove_xdp_program(ifindex, dev->xdp_mode_in_use);
 }
 
 static struct dp_packet_afxdp *
@@ -782,7 +839,8 @@  netdev_afxdp_rxq_recv(struct netdev_rxq *rxq_, struct
dp_packet_batch *batch,  }
 
 static inline int
-kick_tx(struct xsk_socket_info *xsk_info, int xdpmode, bool
use_need_wakeup)
+kick_tx(struct xsk_socket_info *xsk_info, enum afxdp_mode mode,
+        bool use_need_wakeup)
 {
     int ret, retries;
     static const int KERNEL_TX_BATCH_SIZE = 16; @@ -791,11 +849,11 @@
kick_tx(struct xsk_socket_info *xsk_info, int xdpmode, bool use_need_wakeup)
         return 0;
     }
 
-    /* In SKB_MODE packet transmission is synchronous, and the kernel xmits
+    /* In generic mode packet transmission is synchronous, and the 
+ kernel xmits
      * only TX_BATCH_SIZE(16) packets for a single sendmsg syscall.
      * So, we have to kick the kernel (n_packets / 16) times to be sure
that
      * all packets are transmitted. */
-    retries = (xdpmode == XDP_COPY)
+    retries = (mode == OVS_AF_XDP_MODE_GENERIC)
               ? xsk_info->outstanding_tx / KERNEL_TX_BATCH_SIZE
               : 0;
 kick_retry:
@@ -962,7 +1020,7 @@  __netdev_afxdp_batch_send(struct netdev *netdev, int
qid,
                            &orig);
         COVERAGE_INC(afxdp_tx_full);
         afxdp_complete_tx(xsk_info);
-        kick_tx(xsk_info, dev->xdpmode, dev->use_need_wakeup);
+        kick_tx(xsk_info, dev->xdp_mode_in_use, dev->use_need_wakeup);
         error = ENOMEM;
         goto out;
     }
@@ -986,7 +1044,7 @@  __netdev_afxdp_batch_send(struct netdev *netdev, int
qid,
     xsk_ring_prod__submit(&xsk_info->tx, dp_packet_batch_size(batch));
     xsk_info->outstanding_tx += dp_packet_batch_size(batch);
 
-    ret = kick_tx(xsk_info, dev->xdpmode, dev->use_need_wakeup);
+    ret = kick_tx(xsk_info, dev->xdp_mode_in_use, 
+ dev->use_need_wakeup);
     if (OVS_UNLIKELY(ret)) {
         VLOG_WARN_RL(&rl, "%s: error sending AF_XDP packet: %s.",
                      netdev_get_name(netdev), ovs_strerror(ret)); @@ -1052,
10 +1110,11 @@ netdev_afxdp_construct(struct netdev *netdev)
     /* Queues should not be used before the first reconfiguration.
Clearing. */
     netdev->n_rxq = 0;
     netdev->n_txq = 0;
-    dev->xdpmode = 0;
+    dev->xdp_mode = OVS_AF_XDP_MODE_UNSPEC;
+    dev->xdp_mode_in_use = OVS_AF_XDP_MODE_UNSPEC;
 
     dev->requested_n_rxq = NR_QUEUE;
-    dev->requested_xdpmode = XDP_COPY;
+    dev->requested_xdp_mode = OVS_AF_XDP_MODE_BEST_EFFORT;
     dev->requested_need_wakeup = NEED_WAKEUP_DEFAULT;
 
     dev->xsks = NULL;
diff --git a/lib/netdev-afxdp.h b/lib/netdev-afxdp.h index
e2f400b72..4fe861d2d 100644
--- a/lib/netdev-afxdp.h
+++ b/lib/netdev-afxdp.h
@@ -25,6 +25,15 @@ 
 /* These functions are Linux AF_XDP specific, so they should be used
directly
  * only by Linux-specific code. */
 
+enum afxdp_mode {
+    OVS_AF_XDP_MODE_UNSPEC,
+    OVS_AF_XDP_MODE_BEST_EFFORT,
+    OVS_AF_XDP_MODE_NATIVE_ZC,
+    OVS_AF_XDP_MODE_NATIVE,
+    OVS_AF_XDP_MODE_GENERIC,
+    OVS_AF_XDP_MODE_MAX,
+};
+
 struct netdev;
 struct xsk_socket_info;
 struct xdp_umem;
diff --git a/lib/netdev-linux-private.h b/lib/netdev-linux-private.h index
c14f2fb81..8873caa9d 100644
--- a/lib/netdev-linux-private.h
+++ b/lib/netdev-linux-private.h
@@ -100,10 +100,14 @@  struct netdev_linux {
     /* AF_XDP information. */
     struct xsk_socket_info **xsks;
     int requested_n_rxq;
-    int xdpmode;                /* AF_XDP running mode: driver or skb. */
-    int requested_xdpmode;
+
+    enum afxdp_mode xdp_mode;               /* Configured AF_XDP mode. */
+    enum afxdp_mode requested_xdp_mode;     /* Requested  AF_XDP mode. */
+    enum afxdp_mode xdp_mode_in_use;        /* Effective  AF_XDP mode. */
+
     bool use_need_wakeup;
     bool requested_need_wakeup;
+
     struct ovs_spin *tx_locks;  /* spin lock array for TX queues. */
#endif  }; diff --git a/tests/system-afxdp-macros.at
b/tests/system-afxdp-macros.at index f0683c0a9..5ee2ceb1a 100644
--- a/tests/system-afxdp-macros.at
+++ b/tests/system-afxdp-macros.at
@@ -30,10 +30,3 @@  m4_define([CONFIGURE_VETH_OFFLOADS],
      AT_CHECK([ethtool -K $1 txvlan off], [0], [ignore], [ignore])
     ]
 )
-
-# OVS_START_L7([namespace], [protocol]) -# -# AF_XDP doesn't work with TCP
over virtual interfaces for now.
-#
-m4_define([OVS_START_L7],
-   [AT_SKIP_IF([:])])
diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml index
efdfb83bb..02a68deb1 100644
--- a/vswitchd/vswitch.xml
+++ b/vswitchd/vswitch.xml
@@ -3107,18 +3107,38 @@  ovs-vsctl add-port br0 p0 -- set Interface p0
type=patch options:peer=p1 \
         </p>
       </column>
 
-      <column name="options" key="xdpmode"
+      <column name="options" key="xdp-mode"
               type='{"type": "string",
-                     "enum": ["set", ["skb", "drv"]]}'>
+                     "enum": ["set", ["best-effort",
"native-with-zerocopy",
+                                      "native", "generic"]]}'>
         <p>
           Specifies the operational mode of the XDP program.
-          If "drv", the XDP program is loaded into the device driver with
-          zero-copy RX and TX enabled. This mode requires device driver
with
-          AF_XDP support and has the best performance.
-          If "skb", the XDP program is using generic XDP mode in kernel
with
-          extra data copying between userspace and kernel. No device driver
-          support is needed. Note that this is afxdp netdev type only.
-          Defaults to "skb" mode.
+          <p>
+            In <code>native-with-zerocopy</code> mode the XDP program is
loaded
+            into the device driver with zero-copy RX and TX enabled.  This
mode
+            requires device driver support and has the best performance
because
+            there should be no copying of packets.
+          </p>
+          <p>
+            <code>native</code> is the same as
+            <code>native-with-zerocopy</code>, but without zero-copy
+            capability.  This requires at least one copy between kernel and
the
+            userspace. This mode also requires support from device driver.
+          </p>
+          <p>
+            In <code>generic</code> case the XDP program in kernel works
after
+            skb allocation on early stages of packet processing inside the
+            network stack.  This mode doesn't require driver support, but
has
+            much lower performance.
+          </p>
+          <p>