[ovs-dev,RFC,1/2] dpif-netdev: Refactor the miniflow extraction logic using PTYPEs.

diff --git a/lib/dp-packet.h b/lib/dp-packet.h
index b4b721c..9ff42d7 100644
--- a/lib/dp-packet.h
+++ b/lib/dp-packet.h
@@ -80,6 +80,11 @@  struct dp_packet {
     };
 };
 
+struct ptype_offsets {
+    uint16_t l3_ofs;
+    uint16_t l4_ofs;
+};
+
 static inline void *dp_packet_data(const struct dp_packet *);
 static inline void dp_packet_set_data(struct dp_packet *, void *);
 static inline void *dp_packet_base(const struct dp_packet *);
@@ -567,10 +572,16 @@  dp_packet_set_data(struct dp_packet *b, void *data)
 }
 
 static inline void
-dp_packet_reset_packet(struct dp_packet *b, int off)
+__dp_packet_reset_packet(struct dp_packet *b, int off)
 {
     dp_packet_set_size(b, dp_packet_size(b) - off);
     dp_packet_set_data(b, ((unsigned char *) dp_packet_data(b) + off));
+}
+
+static inline void
+dp_packet_reset_packet(struct dp_packet *b, int off)
+{
+    __dp_packet_reset_packet(b, off);
     dp_packet_reset_offsets(b);
 }
 
@@ -691,6 +702,55 @@  reset_dp_packet_checksum_ol_flags(struct dp_packet *p)
 #define reset_dp_packet_checksum_ol_flags(arg)
 #endif
 
+static inline bool
+dp_packet_is_encapsulated(struct dp_packet *p OVS_UNUSED)
+{
+#ifdef DPDK_NETDEV
+    return RTE_ETH_IS_TUNNEL_PKT(p->mbuf.packet_type);
+#else
+    return false;
+#endif
+}
+
+/*
+ * To use ptypes
+ *  82599ES(Niantic)
+ *    Disable vectorization. (Requires CONFIG_RTE_IXGBE_INC_VECTOR=n
+ *                               in config/common_base.)
+ *  XL710/X710(FVL)
+ *    Firmware version >= 5.04 for correct ptype indentification.
+ */
+static inline bool
+dp_packet_is_tunnel(struct dp_packet *p OVS_UNUSED,
+                    struct ptype_offsets *pt_ofs OVS_UNUSED)
+{
+#ifdef DPDK_NETDEV
+#define VXLAN_DST_PORT 4789
+#define ETH_HDR_LEN 14
+    uint32_t ptype = p->mbuf.packet_type;
+
+    /* XXX: Use dp_packet_is_encapsulated(dp_packet) when
+     * ptypes is fixed in future. */
+    if ((ptype & RTE_PTYPE_L4_MASK) == RTE_PTYPE_L4_UDP) {
+        uint32_t hdr_len = (ptype & RTE_PTYPE_L3_IPV4) ?
+                           ETH_HDR_LEN + IP_HEADER_LEN :
+                           ETH_HDR_LEN + IPV6_HEADER_LEN;
+
+        if (pt_ofs) {
+            pt_ofs->l3_ofs = ETH_HDR_LEN;
+            pt_ofs->l4_ofs = hdr_len;
+        }
+        struct udp_header *udp_hdr = dp_packet_at(p, hdr_len, UDP_HEADER_LEN);
+        if (udp_hdr && udp_hdr->udp_dst == htons(VXLAN_DST_PORT)) {
+            return true;
+        }
+    }
+    return false;
+#else
+    return false;
+#endif
+}
+
 enum { NETDEV_MAX_BURST = 32 }; /* Maximum number packets in a batch. */
 
 struct dp_packet_batch {
diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c
index ef8ebf2..a34a1c5 100644
--- a/lib/dpif-netdev.c
+++ b/lib/dpif-netdev.c
@@ -4987,6 +4987,30 @@  dp_netdev_queue_batches(struct dp_packet *pkt,
     packet_batch_per_flow_update(batch, pkt, mf);
 }
 
+static void
+packet_mf_extract(struct dp_packet *pkt, struct netdev_flow_key *key)
+{
+    struct ptype_offsets pt_ofs;
+    if (dp_packet_is_tunnel(pkt, &pt_ofs)) {
+       /* pkt->l3_ofs & pkt->l4_ofs should be valid before invoking
+        * netdev_vxlan_pop_header. pkt->l3_ofs, pkt->l4_ofs are set
+        * as part of miniflow extraction. This means dp_packet_l3() and
+        * dp_packet_l4() works only if mf extraction is invoked early during
+        * packet processing.
+        *
+        * In this case pop header operation should be performed before
+        * mf extraction, so set the dp_packet offsets from the pt_ofs.
+        */
+        pkt->l3_ofs = pt_ofs.l3_ofs;
+        pkt->l4_ofs = pt_ofs.l4_ofs;
+        tunnel_flow_extract(pkt, &key->mf);
+    } else {
+        miniflow_extract(pkt, &key->mf);
+    }
+
+    key->len = 0; /* Not computed yet. */
+}
+
 /* Try to process all ('cnt') the 'packets' using only the exact match cache
  * 'pmd->flow_cache'. If a flow is not found for a packet 'packets[i]', the
  * miniflow is copied into 'keys' and the packet pointer is moved at the
@@ -5037,8 +5061,9 @@  emc_processing(struct dp_netdev_pmd_thread *pmd,
         if (!md_is_valid) {
             pkt_metadata_init(&packet->md, port_no);
         }
-        miniflow_extract(packet, &key->mf);
-        key->len = 0; /* Not computed yet. */
+
+        packet_mf_extract(packet, key);
+
         /* If EMC is disabled skip hash computation and emc_lookup */
         if (cur_min) {
             if (!md_is_valid) {
diff --git a/lib/flow.c b/lib/flow.c
index f9d7c2a..badf7e7 100644
--- a/lib/flow.c
+++ b/lib/flow.c
@@ -32,6 +32,7 @@ 
 #include "openvswitch/dynamic-string.h"
 #include "hash.h"
 #include "jhash.h"
+#include "netdev-native-tnl.h"
 #include "openvswitch/match.h"
 #include "dp-packet.h"
 #include "openflow/openflow.h"
@@ -971,6 +972,43 @@  miniflow_extract(struct dp_packet *packet, struct miniflow *dst)
     dst->map = mf.map;
 }
 
+void
+tunnel_flow_extract(struct dp_packet *packet, struct miniflow *dst)
+{
+    /* vxlan_pop_header shall reset all of tunnel meta data, so
+     * backup the inport and packet offsets before invoking it. */
+    odp_port_t odp_port = packet->md.in_port.odp_port;
+    uint16_t l3_ofs = packet->l3_ofs;
+    uint16_t l4_ofs = packet->l4_ofs;
+
+    /* This would populate the flow_tnl structure, changes the offsets
+     *  of the packet. */
+    netdev_vxlan_pop_header(packet);
+
+    packet->md.in_port.odp_port = odp_port;
+
+    /* As tnl info is populated in packet metadata, do the miniflow
+     * extraction of the packet now. */
+    miniflow_extract(packet, dst);
+
+    /* Reset the data and offsets. */
+    __dp_packet_reset_packet(packet,
+                    -(l4_ofs +
+                      sizeof(struct udp_header) +
+                      sizeof(struct vxlanhdr)));
+
+    /* netdev_vxlan_pop_header()
+     *   dp_packet_reset_packet()
+     *      dp_packet_reset_offsets()
+     *          packet->l3_ofs = UINT16_MAX
+     *          packet->l4_ofs = UINT16_MAX
+     *
+     * vxlan_pop_header() resets the offsets and hence need to be restored.
+     */
+    packet->l3_ofs = l3_ofs;
+    packet->l4_ofs = l4_ofs;
+}
+
 ovs_be16
 parse_dl_type(const struct eth_header *data_, size_t size)
 {
diff --git a/lib/flow.h b/lib/flow.h
index eb1e2bf..395a6c8 100644
--- a/lib/flow.h
+++ b/lib/flow.h
@@ -533,6 +533,7 @@  struct pkt_metadata;
  * 'dst->map' is ignored on input and set on output to indicate which fields
  * were extracted. */
 void miniflow_extract(struct dp_packet *packet, struct miniflow *dst);
+void tunnel_flow_extract(struct dp_packet *packet, struct miniflow *);
 void miniflow_map_init(struct miniflow *, const struct flow *);
 void flow_wc_map(const struct flow *, struct flowmap *);
 size_t miniflow_alloc(struct miniflow *dsts[], size_t n,