Introduce l{2,3,4}_hdr_offset fields in the buffer metadata

To save space in the first cacheline following is changed:

- total_length_not_including_first_buffer moved to the 2nd cacheline.
This field is used only when VLIB_BUFFER_TOTAL_LENGTH_VALID and
VLIB_BUFFER_NEXT_PRESENT are both set.

- free_list_index is now stored in 4bits inside flags, which
allows up to 16 free lists. In case we need more we can store index
in the 2nd cachelin

Change-Id: Ic8521350819391af470d31d3fa1013e67ecb7681
Signed-off-by: Damjan Marion <damarion@cisco.com>

3 files changed, 14 insertions, 17 deletions

diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c
index 8263e01c188..b8dfa8474eb 100755
--- a/src/vnet/ip/ip4_forward.c
+++ b/src/vnet/ip/ip4_forward.c
@@ -1585,8 +1585,8 @@ ip4_local_inline (vlib_main_t * vm,
 	  ip0 = vlib_buffer_get_current (p0);
 	  ip1 = vlib_buffer_get_current (p1);
 
-	  vnet_buffer (p0)->ip.start_of_ip_header = p0->current_data;
-	  vnet_buffer (p1)->ip.start_of_ip_header = p1->current_data;
+	  vnet_buffer (p0)->l3_hdr_offset = p0->current_data;
+	  vnet_buffer (p1)->l3_hdr_offset = p1->current_data;
 
 	  sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
 	  sw_if_index1 = vnet_buffer (p1)->sw_if_index[VLIB_RX];
@@ -1788,7 +1788,7 @@ ip4_local_inline (vlib_main_t * vm,
 
 	  ip0 = vlib_buffer_get_current (p0);
 
-	  vnet_buffer (p0)->ip.start_of_ip_header = p0->current_data;
+	  vnet_buffer (p0)->l3_hdr_offset = p0->current_data;
 
 	  sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
 
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index 4b574b9adbd..2b8c2bd2f7c 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -1362,8 +1362,8 @@ ip6_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 	  ip0 = vlib_buffer_get_current (p0);
 	  ip1 = vlib_buffer_get_current (p1);
 
-	  vnet_buffer (p0)->ip.start_of_ip_header = p0->current_data;
-	  vnet_buffer (p1)->ip.start_of_ip_header = p1->current_data;
+	  vnet_buffer (p0)->l3_hdr_offset = p0->current_data;
+	  vnet_buffer (p1)->l3_hdr_offset = p1->current_data;
 
 	  type0 = lm->builtin_protocol_by_ip_protocol[ip0->protocol];
 	  type1 = lm->builtin_protocol_by_ip_protocol[ip1->protocol];
@@ -1493,7 +1493,7 @@ ip6_local (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
 
 	  ip0 = vlib_buffer_get_current (p0);
 
-	  vnet_buffer (p0)->ip.start_of_ip_header = p0->current_data;
+	  vnet_buffer (p0)->l3_hdr_offset = p0->current_data;
 
 	  type0 = lm->builtin_protocol_by_ip_protocol[ip0->protocol];
 	  next0 = lm->local_next_by_ip_protocol[ip0->protocol];
diff --git a/src/vnet/ip/ip6_neighbor.c b/src/vnet/ip/ip6_neighbor.c
index b8f6f9b10e7..68a8cbbc8d0 100644
--- a/src/vnet/ip/ip6_neighbor.c
+++ b/src/vnet/ip/ip6_neighbor.c
@@ -1479,9 +1479,8 @@ icmp6_router_solicitation (vlib_main_t * vm,
 			sizeof (icmp6_router_advertisement_header_t);
 
 		      vlib_buffer_add_data (vm,
-					    p0->free_list_index,
-					    bi0,
-					    (void *) &rh,
+					    vlib_buffer_get_free_list_index
+					    (p0), bi0, (void *) &rh,
 					    sizeof
 					    (icmp6_router_advertisement_header_t));
 
@@ -1499,9 +1498,8 @@ icmp6_router_solicitation (vlib_main_t * vm,
 				       eth_if0->address, 6);
 
 			  vlib_buffer_add_data (vm,
-						p0->free_list_index,
-						bi0,
-						(void *) &h,
+						vlib_buffer_get_free_list_index
+						(p0), bi0, (void *) &h,
 						sizeof
 						(icmp6_neighbor_discovery_ethernet_link_layer_address_option_t));
 
@@ -1525,9 +1523,8 @@ icmp6_router_solicitation (vlib_main_t * vm,
 			    sizeof (icmp6_neighbor_discovery_mtu_option_t);
 
 			  vlib_buffer_add_data (vm,
-						p0->free_list_index,
-						bi0,
-						(void *) &h,
+						vlib_buffer_get_free_list_index
+						(p0), bi0, (void *) &h,
 						sizeof
 						(icmp6_neighbor_discovery_mtu_option_t));
 			}
@@ -1579,7 +1576,7 @@ icmp6_router_solicitation (vlib_main_t * vm,
                             payload_length += sizeof( icmp6_neighbor_discovery_prefix_information_option_t);
 
                             vlib_buffer_add_data (vm,
-                                                  p0->free_list_index,
+					    vlib_buffer_get_free_list_index (p0),
                                                   bi0,
                                                   (void *)&h, sizeof(icmp6_neighbor_discovery_prefix_information_option_t));
 
@@ -2326,7 +2323,7 @@ ip6_neighbor_send_mldpv2_report (u32 sw_if_index)
     num_addr_records++;
 
     vlib_buffer_add_data
-      (vm, b0->free_list_index, bo0,
+      (vm, vlib_buffer_get_free_list_index (b0), bo0,
        (void *)&rr, sizeof(icmp6_multicast_address_record_t));
 
     payload_length += sizeof( icmp6_multicast_address_record_t);