From 2d18d2ea9f0e3d6c47d365ec135af651b14e8165 Mon Sep 17 00:00:00 2001 From: Nitin Saxena Date: Sat, 4 Jan 2020 12:28:42 +0530 Subject: ip: avoid fib lookup for consecutive pkts having same source IP Type: fix Fixes: be2286b0 This patch does following: - If terminating frame has consecutive packets with same source IP, this patch avoids fib lookup for those packets in ip4-local node. This drops cycle count for ip4-local node on both ARM and x86. It being done by enabling dead code in else {} case of ip4_local_check_src_x2() and ip4_local_check_src() functions. - In case all packets in terminating frame have unique source IP (e.g: incrementing), ip4-local is costlier by 2 cycles (broadwell) Change-Id: I472ddc324716cec8bfe601568b8aeb7565f97ab3 Signed-off-by: Nitin Saxena --- src/vnet/ip/ip4_forward.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c index aa554eab5fb..b8defc56afd 100644 --- a/src/vnet/ip/ip4_forward.c +++ b/src/vnet/ip/ip4_forward.c @@ -1504,8 +1504,8 @@ ip4_local_check_src (vlib_buffer_t * b, ip4_header_t * ip0, * vnet_buffer()->ip.adj_index[VLIB_TX] will be set to the index of the * adjacency for the source address (the remote sender's address) */ - if (PREDICT_FALSE (last_check->first || - (last_check->src.as_u32 != ip0->src_address.as_u32))) + if (PREDICT_TRUE (last_check->src.as_u32 != ip0->src_address.as_u32) || + last_check->first) { mtrie0 = &ip4_fib_get (vnet_buffer (b)->ip.fib_index)->mtrie; leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, &ip0->src_address); @@ -1542,6 +1542,7 @@ ip4_local_check_src (vlib_buffer_t * b, ip4_header_t * ip0, last_check->src.as_u32 = ip0->src_address.as_u32; last_check->lbi = lbi0; last_check->error = *error0; + last_check->first = 0; } else { @@ -1549,7 +1550,6 @@ ip4_local_check_src (vlib_buffer_t * b, ip4_header_t * ip0, vnet_buffer (b)->ip.adj_index[VLIB_TX]; vnet_buffer (b)->ip.adj_index[VLIB_TX] = last_check->lbi; *error0 = last_check->error; - last_check->first = 0; } } @@ -1584,7 +1584,7 @@ ip4_local_check_src_x2 (vlib_buffer_t ** b, ip4_header_t ** ip, * vnet_buffer()->ip.adj_index[VLIB_TX] will be set to the index of the * adjacency for the source address (the remote sender's address) */ - if (PREDICT_FALSE (not_last_hit)) + if (PREDICT_TRUE (not_last_hit)) { mtrie[0] = &ip4_fib_get (vnet_buffer (b[0])->ip.fib_index)->mtrie; mtrie[1] = &ip4_fib_get (vnet_buffer (b[1])->ip.fib_index)->mtrie; @@ -1638,6 +1638,7 @@ ip4_local_check_src_x2 (vlib_buffer_t ** b, ip4_header_t ** ip, last_check->src.as_u32 = ip[1]->src_address.as_u32; last_check->lbi = lbi[1]; last_check->error = error[1]; + last_check->first = 0; } else { @@ -1651,7 +1652,6 @@ ip4_local_check_src_x2 (vlib_buffer_t ** b, ip4_header_t ** ip, error[0] = last_check->error; error[1] = last_check->error; - last_check->first = 0; } } -- cgit 1.2.3-korg