userspace: Enable TSO support for non-DPDK.

This patch enables TSO support for non-DPDK use cases, and
also add check-system-tso testsuite. Before TSO, we have to
disable checksum offload, allowing the kernel to calculate the
TCP/UDP packet checsum. With TSO, we can skip the checksum
validation by enabling checksum offload, and with large packet
size, we see better performance.

Consider container to container use cases:
  iperf3 -c (ns0) -> veth peer -> OVS -> veth peer -> iperf3 -s (ns1)
And I got around 6Gbps, similar to TSO with DPDK-enabled.

Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: William Tu <u9012063@gmail.com>

7 files changed, 340 insertions, 325 deletions

diff --git a/lib/dp-packet.c b/lib/dp-packet.c
index cd2623500..72f6d09ac 100644
--- a/lib/dp-packet.c
+++ b/lib/dp-packet.c
@@ -192,10 +192,8 @@ dp_packet_clone_with_headroom(const struct dp_packet *buffer, size_t headroom)
             sizeof(struct dp_packet) -
             offsetof(struct dp_packet, l2_pad_size));
 
-#ifdef DPDK_NETDEV
-    new_buffer->mbuf.ol_flags = buffer->mbuf.ol_flags;
-    new_buffer->mbuf.ol_flags &= ~DPDK_MBUF_NON_OFFLOADING_FLAGS;
-#endif
+    *dp_packet_ol_flags_ptr(new_buffer) = *dp_packet_ol_flags_ptr(buffer);
+    *dp_packet_ol_flags_ptr(new_buffer) &= DP_PACKET_OL_SUPPORTED_MASK;
 
     if (dp_packet_rss_valid(buffer)) {
         dp_packet_set_rss_hash(new_buffer, dp_packet_get_rss_hash(buffer));
diff --git a/lib/dp-packet.h b/lib/dp-packet.h
index 9f8991faa..0430cca8e 100644
--- a/lib/dp-packet.h
+++ b/lib/dp-packet.h
@@ -48,18 +48,62 @@ enum OVS_PACKED_ENUM dp_packet_source {
 
 #define DP_PACKET_CONTEXT_SIZE 64
 
-#ifndef DPDK_NETDEV
+#ifdef DPDK_NETDEV
+#define DEF_OL_FLAG(NAME, DPDK_DEF, GENERIC_DEF) NAME = DPDK_DEF
+#else
+#define DEF_OL_FLAG(NAME, DPDK_DEF, GENERIC_DEF) NAME = GENERIC_DEF
+#endif
+
 /* Bit masks for the 'ol_flags' member of the 'dp_packet' structure. */
 enum dp_packet_offload_mask {
-    DP_PACKET_OL_RSS_HASH_MASK  = 0x1, /* Is the 'rss_hash' valid? */
-    DP_PACKET_OL_FLOW_MARK_MASK = 0x2, /* Is the 'flow_mark' valid? */
+    /* Value 0 is not used. */
+    /* Is the 'rss_hash' valid? */
+    DEF_OL_FLAG(DP_PACKET_OL_RSS_HASH, PKT_RX_RSS_HASH, 0x1),
+    /* Is the 'flow_mark' valid? */
+    DEF_OL_FLAG(DP_PACKET_OL_FLOW_MARK, PKT_RX_FDIR_ID, 0x2),
+    /* Bad L4 checksum in the packet. */
+    DEF_OL_FLAG(DP_PACKET_OL_RX_L4_CKSUM_BAD, PKT_RX_L4_CKSUM_BAD, 0x4),
+    /* Bad IP checksum in the packet. */
+    DEF_OL_FLAG(DP_PACKET_OL_RX_IP_CKSUM_BAD, PKT_RX_IP_CKSUM_BAD, 0x8),
+    /* Valid L4 checksum in the packet. */
+    DEF_OL_FLAG(DP_PACKET_OL_RX_L4_CKSUM_GOOD, PKT_RX_L4_CKSUM_GOOD, 0x10),
+    /* Valid IP checksum in the packet. */
+    DEF_OL_FLAG(DP_PACKET_OL_RX_IP_CKSUM_GOOD, PKT_RX_IP_CKSUM_GOOD, 0x20),
+    /* TCP Segmentation Offload. */
+    DEF_OL_FLAG(DP_PACKET_OL_TX_TCP_SEG, PKT_TX_TCP_SEG, 0x40),
+    /* Offloaded packet is IPv4. */
+    DEF_OL_FLAG(DP_PACKET_OL_TX_IPV4, PKT_TX_IPV4, 0x80),
+    /* Offloaded packet is IPv6. */
+    DEF_OL_FLAG(DP_PACKET_OL_TX_IPV6, PKT_TX_IPV6, 0x100),
+    /* Offload TCP checksum. */
+    DEF_OL_FLAG(DP_PACKET_OL_TX_TCP_CKSUM, PKT_TX_TCP_CKSUM, 0x200),
+    /* Offload UDP checksum. */
+    DEF_OL_FLAG(DP_PACKET_OL_TX_UDP_CKSUM, PKT_TX_UDP_CKSUM, 0x400),
+    /* Offload SCTP checksum. */
+    DEF_OL_FLAG(DP_PACKET_OL_TX_SCTP_CKSUM, PKT_TX_SCTP_CKSUM, 0x800),
+    /* Adding new field requires adding to DP_PACKET_OL_SUPPORTED_MASK. */
 };
-#else
-/* DPDK mbuf ol_flags that are not really an offload flags.  These are mostly
- * related to mbuf memory layout and OVS should not touch/clear them. */
-#define DPDK_MBUF_NON_OFFLOADING_FLAGS (EXT_ATTACHED_MBUF | \
-                                        IND_ATTACHED_MBUF)
-#endif
+
+#define DP_PACKET_OL_SUPPORTED_MASK (DP_PACKET_OL_RSS_HASH         | \
+                                     DP_PACKET_OL_FLOW_MARK        | \
+                                     DP_PACKET_OL_RX_L4_CKSUM_BAD  | \
+                                     DP_PACKET_OL_RX_IP_CKSUM_BAD  | \
+                                     DP_PACKET_OL_RX_L4_CKSUM_GOOD | \
+                                     DP_PACKET_OL_RX_IP_CKSUM_GOOD | \
+                                     DP_PACKET_OL_TX_TCP_SEG       | \
+                                     DP_PACKET_OL_TX_IPV4          | \
+                                     DP_PACKET_OL_TX_IPV6          | \
+                                     DP_PACKET_OL_TX_TCP_CKSUM     | \
+                                     DP_PACKET_OL_TX_UDP_CKSUM     | \
+                                     DP_PACKET_OL_TX_SCTP_CKSUM)
+
+#define DP_PACKET_OL_TX_L4_MASK (DP_PACKET_OL_TX_TCP_CKSUM | \
+                                 DP_PACKET_OL_TX_UDP_CKSUM | \
+                                 DP_PACKET_OL_TX_SCTP_CKSUM)
+#define DP_PACKET_OL_RX_IP_CKSUM_MASK (DP_PACKET_OL_RX_IP_CKSUM_GOOD | \
+                                       DP_PACKET_OL_RX_IP_CKSUM_BAD)
+#define DP_PACKET_OL_RX_L4_CKSUM_MASK (DP_PACKET_OL_RX_L4_CKSUM_GOOD | \
+                                       DP_PACKET_OL_RX_L4_CKSUM_BAD)
 
 /* Buffer for holding packet data.  A dp_packet is automatically reallocated
  * as necessary if it grows too large for the available memory.
@@ -451,6 +495,45 @@ dp_packet_get_nd_payload(const struct dp_packet *b)
 }
 
 #ifdef DPDK_NETDEV
+static inline uint64_t *
+dp_packet_ol_flags_ptr(const struct dp_packet *b)
+{
+    return CONST_CAST(uint64_t *, &b->mbuf.ol_flags);
+}
+
+static inline uint32_t *
+dp_packet_rss_ptr(const struct dp_packet *b)
+{
+    return CONST_CAST(uint32_t *, &b->mbuf.hash.rss);
+}
+
+static inline uint32_t *
+dp_packet_flow_mark_ptr(const struct dp_packet *b)
+{
+    return CONST_CAST(uint32_t *, &b->mbuf.hash.fdir.hi);
+}
+
+#else
+static inline uint32_t *
+dp_packet_ol_flags_ptr(const struct dp_packet *b)
+{
+    return CONST_CAST(uint32_t *, &b->ol_flags);
+}
+
+static inline uint32_t *
+dp_packet_rss_ptr(const struct dp_packet *b)
+{
+    return CONST_CAST(uint32_t *, &b->rss_hash);
+}
+
+static inline uint32_t *
+dp_packet_flow_mark_ptr(const struct dp_packet *b)
+{
+    return CONST_CAST(uint32_t *, &b->flow_mark);
+}
+#endif
+
+#ifdef DPDK_NETDEV
 BUILD_ASSERT_DECL(offsetof(struct dp_packet, mbuf) == 0);
 
 static inline void
@@ -521,168 +604,6 @@ dp_packet_set_allocated(struct dp_packet *b, uint16_t s)
     b->mbuf.buf_len = s;
 }
 
-/* Returns 'true' if packet 'b' is marked for TCP segmentation offloading. */
-static inline bool
-dp_packet_hwol_is_tso(const struct dp_packet *b)
-{
-    return !!(b->mbuf.ol_flags & PKT_TX_TCP_SEG);
-}
-
-/* Returns 'true' if packet 'b' is marked for IPv4 checksum offloading. */
-static inline bool
-dp_packet_hwol_is_ipv4(const struct dp_packet *b)
-{
-    return !!(b->mbuf.ol_flags & PKT_TX_IPV4);
-}
-
-/* Returns the L4 cksum offload bitmask. */
-static inline uint64_t
-dp_packet_hwol_l4_mask(const struct dp_packet *b)
-{
-    return b->mbuf.ol_flags & PKT_TX_L4_MASK;
-}
-
-/* Returns 'true' if packet 'b' is marked for TCP checksum offloading. */
-static inline bool
-dp_packet_hwol_l4_is_tcp(const struct dp_packet *b)
-{
-    return (b->mbuf.ol_flags & PKT_TX_L4_MASK) == PKT_TX_TCP_CKSUM;
-}
-
-/* Returns 'true' if packet 'b' is marked for UDP checksum offloading. */
-static inline bool
-dp_packet_hwol_l4_is_udp(struct dp_packet *b)
-{
-    return (b->mbuf.ol_flags & PKT_TX_L4_MASK) == PKT_TX_UDP_CKSUM;
-}
-
-/* Returns 'true' if packet 'b' is marked for SCTP checksum offloading. */
-static inline bool
-dp_packet_hwol_l4_is_sctp(struct dp_packet *b)
-{
-    return (b->mbuf.ol_flags & PKT_TX_L4_MASK) == PKT_TX_SCTP_CKSUM;
-}
-
-/* Mark packet 'b' for IPv4 checksum offloading. */
-static inline void
-dp_packet_hwol_set_tx_ipv4(struct dp_packet *b)
-{
-    b->mbuf.ol_flags |= PKT_TX_IPV4;
-}
-
-/* Mark packet 'b' for IPv6 checksum offloading. */
-static inline void
-dp_packet_hwol_set_tx_ipv6(struct dp_packet *b)
-{
-    b->mbuf.ol_flags |= PKT_TX_IPV6;
-}
-
-/* Mark packet 'b' for TCP checksum offloading.  It implies that either
- * the packet 'b' is marked for IPv4 or IPv6 checksum offloading. */
-static inline void
-dp_packet_hwol_set_csum_tcp(struct dp_packet *b)
-{
-    b->mbuf.ol_flags |= PKT_TX_TCP_CKSUM;
-}
-
-/* Mark packet 'b' for UDP checksum offloading.  It implies that either
- * the packet 'b' is marked for IPv4 or IPv6 checksum offloading. */
-static inline void
-dp_packet_hwol_set_csum_udp(struct dp_packet *b)
-{
-    b->mbuf.ol_flags |= PKT_TX_UDP_CKSUM;
-}
-
-/* Mark packet 'b' for SCTP checksum offloading.  It implies that either
- * the packet 'b' is marked for IPv4 or IPv6 checksum offloading. */
-static inline void
-dp_packet_hwol_set_csum_sctp(struct dp_packet *b)
-{
-    b->mbuf.ol_flags |= PKT_TX_SCTP_CKSUM;
-}
-
-/* Mark packet 'b' for TCP segmentation offloading.  It implies that
- * either the packet 'b' is marked for IPv4 or IPv6 checksum offloading
- * and also for TCP checksum offloading. */
-static inline void
-dp_packet_hwol_set_tcp_seg(struct dp_packet *b)
-{
-    b->mbuf.ol_flags |= PKT_TX_TCP_SEG;
-}
-
-/* Returns the RSS hash of the packet 'p'.  Note that the returned value is
- * correct only if 'dp_packet_rss_valid(p)' returns true */
-static inline uint32_t
-dp_packet_get_rss_hash(const struct dp_packet *p)
-{
-    return p->mbuf.hash.rss;
-}
-
-static inline void
-dp_packet_set_rss_hash(struct dp_packet *p, uint32_t hash)
-{
-    p->mbuf.hash.rss = hash;
-    p->mbuf.ol_flags |= PKT_RX_RSS_HASH;
-}
-
-static inline bool
-dp_packet_rss_valid(const struct dp_packet *p)
-{
-    return p->mbuf.ol_flags & PKT_RX_RSS_HASH;
-}
-
-static inline void
-dp_packet_reset_offload(struct dp_packet *p)
-{
-    p->mbuf.ol_flags &= DPDK_MBUF_NON_OFFLOADING_FLAGS;
-}
-
-static inline bool
-dp_packet_ip_checksum_valid(const struct dp_packet *p)
-{
-    return (p->mbuf.ol_flags & PKT_RX_IP_CKSUM_MASK) ==
-            PKT_RX_IP_CKSUM_GOOD;
-}
-
-static inline bool
-dp_packet_ip_checksum_bad(const struct dp_packet *p)
-{
-    return (p->mbuf.ol_flags & PKT_RX_IP_CKSUM_MASK) ==
-            PKT_RX_IP_CKSUM_BAD;
-}
-
-static inline bool
-dp_packet_l4_checksum_valid(const struct dp_packet *p)
-{
-    return (p->mbuf.ol_flags & PKT_RX_L4_CKSUM_MASK) ==
-            PKT_RX_L4_CKSUM_GOOD;
-}
-
-static inline bool
-dp_packet_l4_checksum_bad(const struct dp_packet *p)
-{
-    return (p->mbuf.ol_flags & PKT_RX_L4_CKSUM_MASK) ==
-            PKT_RX_L4_CKSUM_BAD;
-}
-
-static inline bool
-dp_packet_has_flow_mark(const struct dp_packet *p, uint32_t *mark)
-{
-    if (p->mbuf.ol_flags & PKT_RX_FDIR_ID) {
-        *mark = p->mbuf.hash.fdir.hi;
-        return true;
-    }
-
-    return false;
-}
-
-static inline void
-dp_packet_set_flow_mark(struct dp_packet *p, uint32_t mark)
-{
-    p->mbuf.hash.fdir.hi = mark;
-    p->mbuf.ol_flags |= PKT_RX_FDIR_ID;
-}
-
 #else /* DPDK_NETDEV */
 
 static inline void
@@ -739,151 +660,6 @@ dp_packet_set_allocated(struct dp_packet *b, uint16_t s)
     b->allocated_ = s;
 }
 
-/* There are no implementation when not DPDK enabled datapath. */
-static inline bool
-dp_packet_hwol_is_tso(const struct dp_packet *b OVS_UNUSED)
-{
-    return false;
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline bool
-dp_packet_hwol_is_ipv4(const struct dp_packet *b OVS_UNUSED)
-{
-    return false;
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline uint64_t
-dp_packet_hwol_l4_mask(const struct dp_packet *b OVS_UNUSED)
-{
-    return 0;
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline bool
-dp_packet_hwol_l4_is_tcp(const struct dp_packet *b OVS_UNUSED)
-{
-    return false;
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline bool
-dp_packet_hwol_l4_is_udp(const struct dp_packet *b OVS_UNUSED)
-{
-    return false;
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline bool
-dp_packet_hwol_l4_is_sctp(const struct dp_packet *b OVS_UNUSED)
-{
-    return false;
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline void
-dp_packet_hwol_set_tx_ipv4(struct dp_packet *b OVS_UNUSED)
-{
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline void
-dp_packet_hwol_set_tx_ipv6(struct dp_packet *b OVS_UNUSED)
-{
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline void
-dp_packet_hwol_set_csum_tcp(struct dp_packet *b OVS_UNUSED)
-{
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline void
-dp_packet_hwol_set_csum_udp(struct dp_packet *b OVS_UNUSED)
-{
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline void
-dp_packet_hwol_set_csum_sctp(struct dp_packet *b OVS_UNUSED)
-{
-}
-
-/* There are no implementation when not DPDK enabled datapath. */
-static inline void
-dp_packet_hwol_set_tcp_seg(struct dp_packet *b OVS_UNUSED)
-{
-}
-
-/* Returns the RSS hash of the packet 'p'.  Note that the returned value is
- * correct only if 'dp_packet_rss_valid(p)' returns true */
-static inline uint32_t
-dp_packet_get_rss_hash(const struct dp_packet *p)
-{
-    return p->rss_hash;
-}
-
-static inline void
-dp_packet_set_rss_hash(struct dp_packet *p, uint32_t hash)
-{
-    p->rss_hash = hash;
-    p->ol_flags |= DP_PACKET_OL_RSS_HASH_MASK;
-}
-
-static inline bool
-dp_packet_rss_valid(const struct dp_packet *p)
-{
-    return p->ol_flags & DP_PACKET_OL_RSS_HASH_MASK;
-}
-
-static inline void
-dp_packet_reset_offload(struct dp_packet *p)
-{
-    p->ol_flags = 0;
-}
-
-static inline bool
-dp_packet_ip_checksum_valid(const struct dp_packet *p OVS_UNUSED)
-{
-    return false;
-}
-
-static inline bool
-dp_packet_ip_checksum_bad(const struct dp_packet *p OVS_UNUSED)
-{
-    return false;
-}
-
-static inline bool
-dp_packet_l4_checksum_valid(const struct dp_packet *p OVS_UNUSED)
-{
-    return false;
-}
-
-static inline bool
-dp_packet_l4_checksum_bad(const struct dp_packet *p OVS_UNUSED)
-{
-    return false;
-}
-
-static inline bool
-dp_packet_has_flow_mark(const struct dp_packet *p, uint32_t *mark)
-{
-    if (p->ol_flags & DP_PACKET_OL_FLOW_MARK_MASK) {
-        *mark = p->flow_mark;
-        return true;
-    }
-    return false;
-}
-
-static inline void
-dp_packet_set_flow_mark(struct dp_packet *p, uint32_t mark)
-{
-    p->flow_mark = mark;
-    p->ol_flags |= DP_PACKET_OL_FLOW_MARK_MASK;
-}
 #endif /* DPDK_NETDEV */
 
 static inline void
@@ -1112,6 +888,58 @@ dp_packet_batch_reset_cutlen(struct dp_packet_batch *batch)
     }
 }
 
+/* Returns the RSS hash of the packet 'p'.  Note that the returned value is
+ * correct only if 'dp_packet_rss_valid(p)' returns 'true'. */
+static inline uint32_t
+dp_packet_get_rss_hash(const struct dp_packet *p)
+{
+    return *dp_packet_rss_ptr(p);
+}
+
+static inline void
+dp_packet_set_rss_hash(struct dp_packet *p, uint32_t hash)
+{
+    *dp_packet_rss_ptr(p) = hash;
+    *dp_packet_ol_flags_ptr(p) |= DP_PACKET_OL_RSS_HASH;
+}
+
+static inline bool
+dp_packet_rss_valid(const struct dp_packet *p)
+{
+    return *dp_packet_ol_flags_ptr(p) & DP_PACKET_OL_RSS_HASH;
+}
+
+static inline void
+dp_packet_reset_offload(struct dp_packet *p)
+{
+    *dp_packet_ol_flags_ptr(p) &= ~DP_PACKET_OL_SUPPORTED_MASK;
+}
+
+static inline bool
+dp_packet_has_flow_mark(const struct dp_packet *p, uint32_t *mark)
+{
+    if (*dp_packet_ol_flags_ptr(p) & DP_PACKET_OL_FLOW_MARK) {
+        *mark = *dp_packet_flow_mark_ptr(p);
+        return true;
+    }
+
+    return false;
+}
+
+static inline void
+dp_packet_set_flow_mark(struct dp_packet *p, uint32_t mark)
+{
+    *dp_packet_flow_mark_ptr(p) = mark;
+    *dp_packet_ol_flags_ptr(p) |= DP_PACKET_OL_FLOW_MARK;
+}
+
+/* Returns the L4 cksum offload bitmask. */
+static inline uint64_t
+dp_packet_hwol_l4_mask(const struct dp_packet *b)
+{
+    return *dp_packet_ol_flags_ptr(b) & DP_PACKET_OL_TX_L4_MASK;
+}
+
 /* Return true if the packet 'b' requested L4 checksum offload. */
 static inline bool
 dp_packet_hwol_tx_l4_checksum(const struct dp_packet *b)
@@ -1119,6 +947,119 @@ dp_packet_hwol_tx_l4_checksum(const struct dp_packet *b)
     return !!dp_packet_hwol_l4_mask(b);
 }
 
+/* Returns 'true' if packet 'b' is marked for TCP segmentation offloading. */
+static inline bool
+dp_packet_hwol_is_tso(const struct dp_packet *b)
+{
+    return !!(*dp_packet_ol_flags_ptr(b) & DP_PACKET_OL_TX_TCP_SEG);
+}
+
+/* Returns 'true' if packet 'b' is marked for IPv4 checksum offloading. */
+static inline bool
+dp_packet_hwol_is_ipv4(const struct dp_packet *b)
+{
+    return !!(*dp_packet_ol_flags_ptr(b) & DP_PACKET_OL_TX_IPV4);
+}
+
+/* Returns 'true' if packet 'b' is marked for TCP checksum offloading. */
+static inline bool
+dp_packet_hwol_l4_is_tcp(const struct dp_packet *b)
+{
+    return (*dp_packet_ol_flags_ptr(b) & DP_PACKET_OL_TX_L4_MASK) ==
+            DP_PACKET_OL_TX_TCP_CKSUM;
+}
+
+/* Returns 'true' if packet 'b' is marked for UDP checksum offloading. */
+static inline bool
+dp_packet_hwol_l4_is_udp(struct dp_packet *b)
+{
+    return (*dp_packet_ol_flags_ptr(b) & DP_PACKET_OL_TX_L4_MASK) ==
+            DP_PACKET_OL_TX_UDP_CKSUM;
+}
+
+/* Returns 'true' if packet 'b' is marked for SCTP checksum offloading. */
+static inline bool
+dp_packet_hwol_l4_is_sctp(struct dp_packet *b)
+{
+    return (*dp_packet_ol_flags_ptr(b) & DP_PACKET_OL_TX_L4_MASK) ==
+            DP_PACKET_OL_TX_SCTP_CKSUM;
+}
+
+/* Mark packet 'b' for IPv4 checksum offloading. */
+static inline void
+dp_packet_hwol_set_tx_ipv4(struct dp_packet *b)
+{
+    *dp_packet_ol_flags_ptr(b) |= DP_PACKET_OL_TX_IPV4;
+}
+
+/* Mark packet 'b' for IPv6 checksum offloading. */
+static inline void
+dp_packet_hwol_set_tx_ipv6(struct dp_packet *b)
+{
+    *dp_packet_ol_flags_ptr(b) |= DP_PACKET_OL_TX_IPV6;
+}
+
+/* Mark packet 'b' for TCP checksum offloading.  It implies that either
+ * the packet 'b' is marked for IPv4 or IPv6 checksum offloading. */
+static inline void
+dp_packet_hwol_set_csum_tcp(struct dp_packet *b)
+{
+    *dp_packet_ol_flags_ptr(b) |= DP_PACKET_OL_TX_TCP_CKSUM;
+}
+
+/* Mark packet 'b' for UDP checksum offloading.  It implies that either
+ * the packet 'b' is marked for IPv4 or IPv6 checksum offloading. */
+static inline void
+dp_packet_hwol_set_csum_udp(struct dp_packet *b)
+{
+    *dp_packet_ol_flags_ptr(b) |= DP_PACKET_OL_TX_UDP_CKSUM;
+}
+
+/* Mark packet 'b' for SCTP checksum offloading.  It implies that either
+ * the packet 'b' is marked for IPv4 or IPv6 checksum offloading. */
+static inline void
+dp_packet_hwol_set_csum_sctp(struct dp_packet *b)
+{
+    *dp_packet_ol_flags_ptr(b) |= DP_PACKET_OL_TX_SCTP_CKSUM;
+}
+
+/* Mark packet 'b' for TCP segmentation offloading.  It implies that
+ * either the packet 'b' is marked for IPv4 or IPv6 checksum offloading
+ * and also for TCP checksum offloading. */
+static inline void
+dp_packet_hwol_set_tcp_seg(struct dp_packet *b)
+{
+    *dp_packet_ol_flags_ptr(b) |= DP_PACKET_OL_TX_TCP_SEG;
+}
+
+static inline bool
+dp_packet_ip_checksum_valid(const struct dp_packet *p)
+{
+    return (*dp_packet_ol_flags_ptr(p) & DP_PACKET_OL_RX_IP_CKSUM_MASK) ==
+            DP_PACKET_OL_RX_IP_CKSUM_GOOD;
+}
+
+static inline bool
+dp_packet_ip_checksum_bad(const struct dp_packet *p)
+{
+    return (*dp_packet_ol_flags_ptr(p) & DP_PACKET_OL_RX_IP_CKSUM_MASK) ==
+            DP_PACKET_OL_RX_IP_CKSUM_BAD;
+}
+
+static inline bool
+dp_packet_l4_checksum_valid(const struct dp_packet *p)
+{
+    return (*dp_packet_ol_flags_ptr(p) & DP_PACKET_OL_RX_L4_CKSUM_MASK) ==
+            DP_PACKET_OL_RX_L4_CKSUM_GOOD;
+}
+
+static inline bool
+dp_packet_l4_checksum_bad(const struct dp_packet *p)
+{
+    return (*dp_packet_ol_flags_ptr(p) & DP_PACKET_OL_RX_L4_CKSUM_MASK) ==
+            DP_PACKET_OL_RX_L4_CKSUM_BAD;
+}
+
 #ifdef  __cplusplus
 }
 #endif
diff --git a/lib/userspace-tso.c b/lib/userspace-tso.c
index 6a4a0149b..f843c2a76 100644
--- a/lib/userspace-tso.c
+++ b/lib/userspace-tso.c
@@ -34,13 +34,8 @@ userspace_tso_init(const struct smap *ovs_other_config)
         static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
 
         if (ovsthread_once_start(&once)) {
-#ifdef DPDK_NETDEV
             VLOG_INFO("Userspace TCP Segmentation Offloading support enabled");
             userspace_tso = true;
-#else
-            VLOG_WARN("Userspace TCP Segmentation Offloading can not be enabled"
-                      "since OVS is built without DPDK support.");
-#endif
             ovsthread_once_done(&once);
         }
     }
diff --git a/tests/.gitignore b/tests/.gitignore
index 99fdf70d5..45b4f67b2 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -24,6 +24,9 @@
 /system-userspace-testsuite
 /system-userspace-testsuite.dir/
 /system-userspace-testsuite.log
+/system-tso-testsuite
+/system-tso-testsuite.dir/
+/system-tso-testsuite.log
 /system-offloads-testsuite
 /system-offloads-testsuite.dir/
 /system-offloads-testsuite.log
diff --git a/tests/automake.mk b/tests/automake.mk
index 81eb2a9b8..66859d537 100644
--- a/tests/automake.mk
+++ b/tests/automake.mk
@@ -4,6 +4,7 @@ EXTRA_DIST += \
 	$(SYSTEM_TESTSUITE_AT) \
 	$(SYSTEM_KMOD_TESTSUITE_AT) \
 	$(SYSTEM_USERSPACE_TESTSUITE_AT) \
+	$(SYSTEM_TSO_TESTSUITE_AT) \
 	$(SYSTEM_AFXDP_TESTSUITE_AT) \
 	$(SYSTEM_OFFLOADS_TESTSUITE_AT) \
 	$(SYSTEM_DPDK_TESTSUITE_AT) \
@@ -11,6 +12,7 @@ EXTRA_DIST += \
 	$(TESTSUITE) \
 	$(SYSTEM_KMOD_TESTSUITE) \
 	$(SYSTEM_USERSPACE_TESTSUITE) \
+	$(SYSTEM_TSO_TESTSUITE) \
 	$(SYSTEM_AFXDP_TESTSUITE) \
 	$(SYSTEM_OFFLOADS_TESTSUITE) \
 	$(SYSTEM_DPDK_TESTSUITE) \
@@ -154,6 +156,10 @@ SYSTEM_USERSPACE_TESTSUITE_AT = \
 	tests/system-userspace-macros.at \
 	tests/system-userspace-packet-type-aware.at
 
+SYSTEM_TSO_TESTSUITE_AT = \
+	tests/system-tso-testsuite.at \
+	tests/system-tso-macros.at
+
 SYSTEM_AFXDP_TESTSUITE_AT = \
 	tests/system-userspace-macros.at \
 	tests/system-afxdp-testsuite.at \
@@ -183,6 +189,7 @@ TESTSUITE = $(srcdir)/tests/testsuite
 TESTSUITE_PATCH = $(srcdir)/tests/testsuite.patch
 SYSTEM_KMOD_TESTSUITE = $(srcdir)/tests/system-kmod-testsuite
 SYSTEM_USERSPACE_TESTSUITE = $(srcdir)/tests/system-userspace-testsuite
+SYSTEM_TSO_TESTSUITE = $(srcdir)/tests/system-tso-testsuite
 SYSTEM_AFXDP_TESTSUITE = $(srcdir)/tests/system-afxdp-testsuite
 SYSTEM_OFFLOADS_TESTSUITE = $(srcdir)/tests/system-offloads-testsuite
 SYSTEM_DPDK_TESTSUITE = $(srcdir)/tests/system-dpdk-testsuite
@@ -296,6 +303,12 @@ check-offloads-valgrind: all $(valgrind_wrappers) $(check_DATA)
 	@echo '----------------------------------------------------------------------'
 	@echo 'Valgrind output can be found in tests/system-offloads-testsuite.dir/*/valgrind.*'
 	@echo '----------------------------------------------------------------------'
+check-tso-valgrind: all $(valgrind_wrappers) $(check_DATA)
+	$(SHELL) '$(SYSTEM_TSO_TESTSUITE)' -C tests VALGRIND='$(VALGRIND)' AUTOTEST_PATH='tests/valgrind:$(AUTOTEST_PATH)' -d $(TESTSUITEFLAGS) -j1
+	@echo
+	@echo '----------------------------------------------------------------------'
+	@echo 'Valgrind output can be found in tests/system-tso-testsuite.dir/*/valgrind.*'
+	@echo '----------------------------------------------------------------------'
 check-helgrind: all $(valgrind_wrappers) $(check_DATA)
 	-$(SHELL) '$(TESTSUITE)' -C tests CHECK_VALGRIND=true VALGRIND='$(HELGRIND)' AUTOTEST_PATH='tests/valgrind:$(AUTOTEST_PATH)' -d $(TESTSUITEFLAGS)
 
@@ -326,6 +339,10 @@ check-system-userspace: all
 	set $(SHELL) '$(SYSTEM_USERSPACE_TESTSUITE)' -C tests  AUTOTEST_PATH='$(AUTOTEST_PATH)'; \
 	"$$@" $(TESTSUITEFLAGS) -j1 || (test X'$(RECHECK)' = Xyes && "$$@" --recheck)
 
+check-system-tso: all
+	set $(SHELL) '$(SYSTEM_TSO_TESTSUITE)' -C tests  AUTOTEST_PATH='$(AUTOTEST_PATH)'; \
+	"$$@" $(TESTSUITEFLAGS) -j1 || (test X'$(RECHECK)' = Xyes && "$$@" --recheck)
+
 check-afxdp: all
 	set $(SHELL) '$(SYSTEM_AFXDP_TESTSUITE)' -C tests  AUTOTEST_PATH='$(AUTOTEST_PATH)' $(TESTSUITEFLAGS) -j1; \
 	"$$@" || (test X'$(RECHECK)' = Xyes && "$$@" --recheck)
@@ -367,6 +384,10 @@ $(SYSTEM_USERSPACE_TESTSUITE): package.m4 $(SYSTEM_TESTSUITE_AT) $(SYSTEM_USERSP
 	$(AM_V_GEN)$(AUTOTEST) -I '$(srcdir)' -o $@.tmp $@.at
 	$(AM_V_at)mv $@.tmp $@
 
+$(SYSTEM_TSO_TESTSUITE): package.m4 $(SYSTEM_TESTSUITE_AT) $(SYSTEM_TSO_TESTSUITE_AT) $(COMMON_MACROS_AT)
+	$(AM_V_GEN)$(AUTOTEST) -I '$(srcdir)' -o $@.tmp $@.at
+	$(AM_V_at)mv $@.tmp $@
+
 $(SYSTEM_AFXDP_TESTSUITE): package.m4 $(SYSTEM_TESTSUITE_AT) $(SYSTEM_AFXDP_TESTSUITE_AT) $(COMMON_MACROS_AT)
 	$(AM_V_GEN)$(AUTOTEST) -I '$(srcdir)' -o $@.tmp $@.at
 	$(AM_V_at)mv $@.tmp $@
diff --git a/tests/system-tso-macros.at b/tests/system-tso-macros.at
new file mode 100644
index 000000000..406334f3e
--- /dev/null
+++ b/tests/system-tso-macros.at
@@ -0,0 +1,31 @@
+# _ADD_BR([name])
+#
+# Expands into the proper ovs-vsctl commands to create a bridge with the
+# appropriate type and properties
+m4_define([_ADD_BR], [[add-br $1 -- set Bridge $1 datapath_type="netdev" protocols=OpenFlow10,OpenFlow11,OpenFlow12,OpenFlow13,OpenFlow14,OpenFlow15 fail-mode=secure ]])
+
+# OVS_TRAFFIC_VSWITCHD_START([vsctl-args], [vsctl-output], [=override])
+#
+# Creates a database and starts ovsdb-server, starts ovs-vswitchd
+# connected to that database, calls ovs-vsctl to create a bridge named
+# br0 with predictable settings, passing 'vsctl-args' as additional
+# commands to ovs-vsctl.  If 'vsctl-args' causes ovs-vsctl to provide
+# output (e.g. because it includes "create" commands) then 'vsctl-output'
+# specifies the expected output after filtering through uuidfilt.
+m4_define([OVS_TRAFFIC_VSWITCHD_START],
+  [
+   OVS_WAIT_WHILE([ip link show ovs-netdev])
+   _OVS_VSWITCHD_START([--disable-system])
+   dnl Add bridges, ports, etc.
+   OVS_WAIT_WHILE([ip link show br0])
+   AT_CHECK([ovs-vsctl set Open_vSwitch . other_config:userspace-tso-enable=true])
+   AT_CHECK([ovs-vsctl -- _ADD_BR([br0]) -- $1 m4_if([$2], [], [], [| uuidfilt])], [0], [$2])
+])
+
+# CONFIGURE_VETH_OFFLOADS([VETH])
+#
+# Enable TCP segmentation offload and scatter-gather for veths.
+m4_define([CONFIGURE_VETH_OFFLOADS],
+    [AT_CHECK([ethtool -K $1 sg on], [0], [ignore], [ignore])]
+    [AT_CHECK([ethtool -K $1 tso on], [0], [ignore], [ignore])]
+)
diff --git a/tests/system-tso-testsuite.at b/tests/system-tso-testsuite.at
new file mode 100644
index 000000000..99d748006
--- /dev/null
+++ b/tests/system-tso-testsuite.at
@@ -0,0 +1,26 @@
+AT_INIT
+
+AT_COPYRIGHT([Copyright (c) 2020 VMware, Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at:
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.])
+
+m4_ifdef([AT_COLOR_TESTS], [AT_COLOR_TESTS])
+
+m4_include([tests/ovs-macros.at])
+m4_include([tests/ovsdb-macros.at])
+m4_include([tests/ofproto-macros.at])
+m4_include([tests/system-common-macros.at])
+m4_include([tests/system-userspace-macros.at])
+m4_include([tests/system-tso-macros.at])
+
+m4_include([tests/system-traffic.at])