ipsec4-output: add pkt header and data prefetching
The graph node running IPsec encap in tunnel mode can be saved
from 65.8 to 57.3 clocks/pkt on Haswell platform.
The graph node can be saved 10 clockes/pkt on DVN as well in the
same case.
@@ -194,8 +194,8 @@ ipsec_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
while (n_left_from > 0)
{
- u32 bi0, pi0;
- vlib_buffer_t *b0;
+ u32 bi0, pi0, bi1;
+ vlib_buffer_t *b0, *b1;
ipsec_policy_t *p0;
ip4_header_t *ip0;
ip6_header_t *ip6_0 = 0;
@@ -205,11 +205,18 @@ ipsec_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
u64 bytes0;
bi0 = from[0];
+ bi1 = from[1];
b0 = vlib_get_buffer (vm, bi0);
+ b1 = vlib_get_buffer (vm, bi1);
sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
iph_offset = vnet_buffer (b0)->ip.save_rewrite_length;
ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0)
+ iph_offset);
+ if (n_left_from > 1)
+ {
+ CLIB_PREFETCH (b1, CLIB_CACHE_LINE_BYTES * 2, STORE);
+ vlib_prefetch_buffer_data (b1, LOAD);
+ }
/* lookup for SPD only if sw_if_index is changed */
if (PREDICT_FALSE (last_sw_if_index != sw_if_index0))
