vxlan-gbp: prefetch encap header memory area

This patch helps save 4.1 clocks/pkt from 62.9 to 58.8
clocks/pkt on Skylake.

Change-Id: I749a88a8fa6c78243441a89d6afcd04f106af3da
Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>

1 files changed, 70 insertions, 66 deletions

diff --git a/src/vnet/vxlan-gbp/encap.c b/src/vnet/vxlan-gbp/encap.c
index 85d6f7787c4..9766d1c3ca1 100644
--- a/src/vnet/vxlan-gbp/encap.c
+++ b/src/vnet/vxlan-gbp/encap.c
@@ -87,9 +87,11 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
   u32 next0 = 0, next1 = 0;
   vxlan_gbp_tunnel_t *t0 = NULL, *t1 = NULL;
   index_t dpoi_idx0 = INDEX_INVALID, dpoi_idx1 = INDEX_INVALID;
+  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 
   from = vlib_frame_vector_args (from_frame);
   n_left_from = from_frame->n_vectors;
+  vlib_get_buffers (vm, from, bufs, n_left_from);
 
   next_index = node->cached_next_index;
 
@@ -121,8 +123,10 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	    vlib_prefetch_buffer_header (p2, LOAD);
 	    vlib_prefetch_buffer_header (p3, LOAD);
 
-	    CLIB_PREFETCH (p2->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
-	    CLIB_PREFETCH (p3->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
+	    CLIB_PREFETCH (b[2]->data - CLIB_CACHE_LINE_BYTES,
+			   2 * CLIB_CACHE_LINE_BYTES, LOAD);
+	    CLIB_PREFETCH (b[3]->data - CLIB_CACHE_LINE_BYTES,
+			   2 * CLIB_CACHE_LINE_BYTES, LOAD);
 	  }
 
 	  u32 bi0 = to_next[0] = from[0];
@@ -132,15 +136,13 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	  n_left_to_next -= 2;
 	  n_left_from -= 2;
 
-	  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
-	  vlib_buffer_t *b1 = vlib_get_buffer (vm, bi1);
-	  u32 flow_hash0 = vnet_l2_compute_flow_hash (b0);
-	  u32 flow_hash1 = vnet_l2_compute_flow_hash (b1);
+	  u32 flow_hash0 = vnet_l2_compute_flow_hash (b[0]);
+	  u32 flow_hash1 = vnet_l2_compute_flow_hash (b[1]);
 
 	  /* Get next node index and adj index from tunnel next_dpo */
-	  if (sw_if_index0 != vnet_buffer (b0)->sw_if_index[VLIB_TX])
+	  if (sw_if_index0 != vnet_buffer (b[0])->sw_if_index[VLIB_TX])
 	    {
-	      sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
+	      sw_if_index0 = vnet_buffer (b[0])->sw_if_index[VLIB_TX];
 	      vnet_hw_interface_t *hi0 =
 		vnet_get_sup_hw_interface (vnm, sw_if_index0);
 	      t0 = &vxm->tunnels[hi0->dev_instance];
@@ -150,9 +152,9 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	    }
 
 	  /* Get next node index and adj index from tunnel next_dpo */
-	  if (sw_if_index1 != vnet_buffer (b1)->sw_if_index[VLIB_TX])
+	  if (sw_if_index1 != vnet_buffer (b[1])->sw_if_index[VLIB_TX])
 	    {
-	      if (sw_if_index0 == vnet_buffer (b1)->sw_if_index[VLIB_TX])
+	      if (sw_if_index0 == vnet_buffer (b[1])->sw_if_index[VLIB_TX])
 		{
 		  sw_if_index1 = sw_if_index0;
 		  t1 = t0;
@@ -161,7 +163,7 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 		}
 	      else
 		{
-		  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_TX];
+		  sw_if_index1 = vnet_buffer (b[1])->sw_if_index[VLIB_TX];
 		  vnet_hw_interface_t *hi1 =
 		    vnet_get_sup_hw_interface (vnm, sw_if_index1);
 		  t1 = &vxm->tunnels[hi1->dev_instance];
@@ -171,25 +173,25 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 		}
 	    }
 
-	  vnet_buffer (b0)->ip.adj_index[VLIB_TX] = dpoi_idx0;
-	  vnet_buffer (b1)->ip.adj_index[VLIB_TX] = dpoi_idx1;
+	  vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = dpoi_idx0;
+	  vnet_buffer (b[1])->ip.adj_index[VLIB_TX] = dpoi_idx1;
 
 	  ASSERT (t0->rewrite_header.data_bytes == underlay_hdr_len);
 	  ASSERT (t1->rewrite_header.data_bytes == underlay_hdr_len);
-	  vnet_rewrite_two_headers (*t0, *t1, vlib_buffer_get_current (b0),
-				    vlib_buffer_get_current (b1),
+	  vnet_rewrite_two_headers (*t0, *t1, vlib_buffer_get_current (b[0]),
+				    vlib_buffer_get_current (b[1]),
 				    underlay_hdr_len);
 
-	  vlib_buffer_advance (b0, -underlay_hdr_len);
-	  vlib_buffer_advance (b1, -underlay_hdr_len);
+	  vlib_buffer_advance (b[0], -underlay_hdr_len);
+	  vlib_buffer_advance (b[1], -underlay_hdr_len);
 
-	  u32 len0 = vlib_buffer_length_in_chain (vm, b0);
-	  u32 len1 = vlib_buffer_length_in_chain (vm, b1);
+	  u32 len0 = vlib_buffer_length_in_chain (vm, b[0]);
+	  u32 len1 = vlib_buffer_length_in_chain (vm, b[1]);
 	  u16 payload_l0 = clib_host_to_net_u16 (len0 - l3_len);
 	  u16 payload_l1 = clib_host_to_net_u16 (len1 - l3_len);
 
-	  void *underlay0 = vlib_buffer_get_current (b0);
-	  void *underlay1 = vlib_buffer_get_current (b1);
+	  void *underlay0 = vlib_buffer_get_current (b[0]);
+	  void *underlay1 = vlib_buffer_get_current (b[1]);
 
 	  ip4_header_t *ip4_0, *ip4_1;
 	  qos_bits_t ip4_0_tos = 0, ip4_1_tos = 0;
@@ -208,14 +210,14 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	      ip4_0->length = clib_host_to_net_u16 (len0);
 	      ip4_1->length = clib_host_to_net_u16 (len1);
 
-	      if (PREDICT_FALSE (b0->flags & VNET_BUFFER_F_QOS_DATA_VALID))
+	      if (PREDICT_FALSE (b[0]->flags & VNET_BUFFER_F_QOS_DATA_VALID))
 		{
-		  ip4_0_tos = vnet_buffer2 (b0)->qos.bits;
+		  ip4_0_tos = vnet_buffer2 (b[0])->qos.bits;
 		  ip4_0->tos = ip4_0_tos;
 		}
-	      if (PREDICT_FALSE (b1->flags & VNET_BUFFER_F_QOS_DATA_VALID))
+	      if (PREDICT_FALSE (b[1]->flags & VNET_BUFFER_F_QOS_DATA_VALID))
 		{
-		  ip4_1_tos = vnet_buffer2 (b1)->qos.bits;
+		  ip4_1_tos = vnet_buffer2 (b[1])->qos.bits;
 		  ip4_1->tos = ip4_1_tos;
 		}
 
@@ -252,21 +254,21 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	  udp1->src_port = flow_hash1;
 
 	  /* set source class and gpflags */
-	  vxlan_gbp0->gpflags = vnet_buffer2 (b0)->gbp.flags;
-	  vxlan_gbp1->gpflags = vnet_buffer2 (b1)->gbp.flags;
+	  vxlan_gbp0->gpflags = vnet_buffer2 (b[0])->gbp.flags;
+	  vxlan_gbp1->gpflags = vnet_buffer2 (b[1])->gbp.flags;
 	  vxlan_gbp0->sclass =
-	    clib_host_to_net_u16 (vnet_buffer2 (b0)->gbp.sclass);
+	    clib_host_to_net_u16 (vnet_buffer2 (b[0])->gbp.sclass);
 	  vxlan_gbp1->sclass =
-	    clib_host_to_net_u16 (vnet_buffer2 (b1)->gbp.sclass);
+	    clib_host_to_net_u16 (vnet_buffer2 (b[1])->gbp.sclass);
 
 	  if (csum_offload)
 	    {
-	      b0->flags |= csum_flags;
-	      vnet_buffer (b0)->l3_hdr_offset = l3_0 - b0->data;
-	      vnet_buffer (b0)->l4_hdr_offset = (u8 *) udp0 - b0->data;
-	      b1->flags |= csum_flags;
-	      vnet_buffer (b1)->l3_hdr_offset = l3_1 - b1->data;
-	      vnet_buffer (b1)->l4_hdr_offset = (u8 *) udp1 - b1->data;
+	      b[0]->flags |= csum_flags;
+	      vnet_buffer (b[0])->l3_hdr_offset = l3_0 - b[0]->data;
+	      vnet_buffer (b[0])->l4_hdr_offset = (u8 *) udp0 - b[0]->data;
+	      b[1]->flags |= csum_flags;
+	      vnet_buffer (b[1])->l3_hdr_offset = l3_1 - b[1]->data;
+	      vnet_buffer (b[1])->l4_hdr_offset = (u8 *) udp1 - b[1]->data;
 	    }
 	  /* IPv4 UDP checksum only if checksum offload is used */
 	  else if (is_ip4)
@@ -296,12 +298,12 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	      int bogus = 0;
 
 	      udp0->checksum = ip6_tcp_udp_icmp_compute_checksum
-		(vm, b0, ip6_0, &bogus);
+		(vm, b[0], ip6_0, &bogus);
 	      ASSERT (bogus == 0);
 	      if (udp0->checksum == 0)
 		udp0->checksum = 0xffff;
 	      udp1->checksum = ip6_tcp_udp_icmp_compute_checksum
-		(vm, b1, ip6_1, &bogus);
+		(vm, b[1], ip6_1, &bogus);
 	      ASSERT (bogus == 0);
 	      if (udp1->checksum == 0)
 		udp1->checksum = 0xffff;
@@ -313,25 +315,26 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 					   sw_if_index1, 1, len1);
 	  pkts_encapsulated += 2;
 
-	  if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+	  if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
 	    {
 	      vxlan_gbp_encap_trace_t *tr =
-		vlib_add_trace (vm, node, b0, sizeof (*tr));
+		vlib_add_trace (vm, node, b[0], sizeof (*tr));
 	      tr->tunnel_index = t0 - vxm->tunnels;
 	      tr->vni = t0->vni;
-	      tr->sclass = vnet_buffer2 (b0)->gbp.sclass;
-	      tr->flags = vnet_buffer2 (b0)->gbp.flags;
+	      tr->sclass = vnet_buffer2 (b[0])->gbp.sclass;
+	      tr->flags = vnet_buffer2 (b[0])->gbp.flags;
 	    }
 
-	  if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
+	  if (PREDICT_FALSE (b[1]->flags & VLIB_BUFFER_IS_TRACED))
 	    {
 	      vxlan_gbp_encap_trace_t *tr =
-		vlib_add_trace (vm, node, b1, sizeof (*tr));
+		vlib_add_trace (vm, node, b[1], sizeof (*tr));
 	      tr->tunnel_index = t1 - vxm->tunnels;
 	      tr->vni = t1->vni;
-	      tr->sclass = vnet_buffer2 (b1)->gbp.sclass;
-	      tr->flags = vnet_buffer2 (b1)->gbp.flags;
+	      tr->sclass = vnet_buffer2 (b[1])->gbp.sclass;
+	      tr->flags = vnet_buffer2 (b[1])->gbp.flags;
 	    }
+	  b += 2;
 
 	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
 					   to_next, n_left_to_next,
@@ -346,13 +349,12 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	  n_left_from -= 1;
 	  n_left_to_next -= 1;
 
-	  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
-	  u32 flow_hash0 = vnet_l2_compute_flow_hash (b0);
+	  u32 flow_hash0 = vnet_l2_compute_flow_hash (b[0]);
 
 	  /* Get next node index and adj index from tunnel next_dpo */
-	  if (sw_if_index0 != vnet_buffer (b0)->sw_if_index[VLIB_TX])
+	  if (sw_if_index0 != vnet_buffer (b[0])->sw_if_index[VLIB_TX])
 	    {
-	      sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
+	      sw_if_index0 = vnet_buffer (b[0])->sw_if_index[VLIB_TX];
 	      vnet_hw_interface_t *hi0 =
 		vnet_get_sup_hw_interface (vnm, sw_if_index0);
 	      t0 = &vxm->tunnels[hi0->dev_instance];
@@ -360,16 +362,16 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	      next0 = t0->next_dpo.dpoi_next_node;
 	      dpoi_idx0 = t0->next_dpo.dpoi_index;
 	    }
-	  vnet_buffer (b0)->ip.adj_index[VLIB_TX] = dpoi_idx0;
+	  vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = dpoi_idx0;
 
 	  ASSERT (t0->rewrite_header.data_bytes == underlay_hdr_len);
-	  vnet_rewrite_one_header (*t0, vlib_buffer_get_current (b0),
+	  vnet_rewrite_one_header (*t0, vlib_buffer_get_current (b[0]),
 				   underlay_hdr_len);
 
-	  vlib_buffer_advance (b0, -underlay_hdr_len);
-	  void *underlay0 = vlib_buffer_get_current (b0);
+	  vlib_buffer_advance (b[0], -underlay_hdr_len);
+	  void *underlay0 = vlib_buffer_get_current (b[0]);
 
-	  u32 len0 = vlib_buffer_length_in_chain (vm, b0);
+	  u32 len0 = vlib_buffer_length_in_chain (vm, b[0]);
 	  u16 payload_l0 = clib_host_to_net_u16 (len0 - l3_len);
 
 	  vxlan_gbp_header_t *vxlan_gbp0;
@@ -386,9 +388,9 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	      ip4_0 = &hdr->ip4;
 	      ip4_0->length = clib_host_to_net_u16 (len0);
 
-	      if (PREDICT_FALSE (b0->flags & VNET_BUFFER_F_QOS_DATA_VALID))
+	      if (PREDICT_FALSE (b[0]->flags & VNET_BUFFER_F_QOS_DATA_VALID))
 		{
-		  ip4_0_tos = vnet_buffer2 (b0)->qos.bits;
+		  ip4_0_tos = vnet_buffer2 (b[0])->qos.bits;
 		  ip4_0->tos = ip4_0_tos;
 		}
 
@@ -414,15 +416,15 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	  udp0->src_port = flow_hash0;
 
 	  /* set source class and gpflags */
-	  vxlan_gbp0->gpflags = vnet_buffer2 (b0)->gbp.flags;
+	  vxlan_gbp0->gpflags = vnet_buffer2 (b[0])->gbp.flags;
 	  vxlan_gbp0->sclass =
-	    clib_host_to_net_u16 (vnet_buffer2 (b0)->gbp.sclass);
+	    clib_host_to_net_u16 (vnet_buffer2 (b[0])->gbp.sclass);
 
 	  if (csum_offload)
 	    {
-	      b0->flags |= csum_flags;
-	      vnet_buffer (b0)->l3_hdr_offset = l3_0 - b0->data;
-	      vnet_buffer (b0)->l4_hdr_offset = (u8 *) udp0 - b0->data;
+	      b[0]->flags |= csum_flags;
+	      vnet_buffer (b[0])->l3_hdr_offset = l3_0 - b[0]->data;
+	      vnet_buffer (b[0])->l4_hdr_offset = (u8 *) udp0 - b[0]->data;
 	    }
 	  /* IPv4 UDP checksum only if checksum offload is used */
 	  else if (is_ip4)
@@ -443,7 +445,7 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 	      int bogus = 0;
 
 	      udp0->checksum = ip6_tcp_udp_icmp_compute_checksum
-		(vm, b0, ip6_0, &bogus);
+		(vm, b[0], ip6_0, &bogus);
 	      ASSERT (bogus == 0);
 	      if (udp0->checksum == 0)
 		udp0->checksum = 0xffff;
@@ -453,15 +455,17 @@ vxlan_gbp_encap_inline (vlib_main_t * vm,
 					   sw_if_index0, 1, len0);
 	  pkts_encapsulated++;
 
-	  if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+	  if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
 	    {
 	      vxlan_gbp_encap_trace_t *tr =
-		vlib_add_trace (vm, node, b0, sizeof (*tr));
+		vlib_add_trace (vm, node, b[0], sizeof (*tr));
 	      tr->tunnel_index = t0 - vxm->tunnels;
 	      tr->vni = t0->vni;
-	      tr->sclass = vnet_buffer2 (b0)->gbp.sclass;
-	      tr->flags = vnet_buffer2 (b0)->gbp.flags;
+	      tr->sclass = vnet_buffer2 (b[0])->gbp.sclass;
+	      tr->flags = vnet_buffer2 (b[0])->gbp.flags;
 	    }
+	  b += 1;
+
 	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 					   to_next, n_left_to_next,
 					   bi0, next0);