From 9a0f2a5e7f678de58807fd49d47deec367656715 Mon Sep 17 00:00:00 2001 From: Damjan Marion Date: Thu, 16 Jul 2020 16:22:48 +0200 Subject: ip: optimize ip4_header_checksum, take 2 - add 64-bit version - remove byte swaps, as they are actually not needed Type: improvement Change-Id: Ia1efe54ee80b4ae7633b9ab36b3154c3357006d7 Signed-off-by: Damjan Marion --- src/vnet/ip/ip4_packet.h | 104 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 72 insertions(+), 32 deletions(-) (limited to 'src/vnet/ip/ip4_packet.h') diff --git a/src/vnet/ip/ip4_packet.h b/src/vnet/ip/ip4_packet.h index 9d63baecf88..fee0c8cbcd7 100644 --- a/src/vnet/ip/ip4_packet.h +++ b/src/vnet/ip/ip4_packet.h @@ -200,61 +200,101 @@ ip4_next_header (ip4_header_t * i) always_inline u16 ip4_header_checksum (ip4_header_t * i) { - u16 *iphdr = (u16 *) i; - u32 sum = 0; int option_len = (i->ip_version_and_header_length & 0xf) - 5; + uword sum = 0; +#if uword_bits == 64 + u32 *iphdr = (u32 *) i; + + sum += iphdr[0]; + sum += iphdr[1]; + sum += *(u16 *) (iphdr + 2); + /* skip checksum */ + sum += iphdr[3]; + sum += iphdr[4]; + + if (PREDICT_FALSE (option_len > 0)) + switch (option_len) + { + case 10: + sum += iphdr[14]; + case 9: + sum += iphdr[13]; + case 8: + sum += iphdr[12]; + case 7: + sum += iphdr[11]; + case 6: + sum += iphdr[10]; + case 5: + sum += iphdr[9]; + case 4: + sum += iphdr[8]; + case 3: + sum += iphdr[7]; + case 2: + sum += iphdr[6]; + case 1: + sum += iphdr[5]; + default: + break; + } - sum += clib_net_to_host_u16 (iphdr[0]); - sum += clib_net_to_host_u16 (iphdr[1]); - sum += clib_net_to_host_u16 (iphdr[2]); - sum += clib_net_to_host_u16 (iphdr[3]); - sum += clib_net_to_host_u16 (iphdr[4]); + sum = ((u32) sum) + (sum >> 32); +#else + u16 *iphdr = (u16 *) i; - sum += clib_net_to_host_u16 (iphdr[6]); - sum += clib_net_to_host_u16 (iphdr[7]); - sum += clib_net_to_host_u16 (iphdr[8]); - sum += clib_net_to_host_u16 (iphdr[9]); + sum += iphdr[0]; + sum += iphdr[1]; + sum += iphdr[2]; + sum += iphdr[3]; + sum += iphdr[4]; + /* skip checksum */ + sum += iphdr[6]; + sum += iphdr[7]; + sum += iphdr[8]; + sum += iphdr[9]; if (PREDICT_FALSE (option_len > 0)) switch (option_len) { case 10: - sum += clib_net_to_host_u16 (iphdr[28]); - sum += clib_net_to_host_u16 (iphdr[29]); + sum += iphdr[28]; + sum += iphdr[29]; case 9: - sum += clib_net_to_host_u16 (iphdr[26]); - sum += clib_net_to_host_u16 (iphdr[27]); + sum += iphdr[26]; + sum += iphdr[27]; case 8: - sum += clib_net_to_host_u16 (iphdr[24]); - sum += clib_net_to_host_u16 (iphdr[25]); + sum += iphdr[24]; + sum += iphdr[25]; case 7: - sum += clib_net_to_host_u16 (iphdr[22]); - sum += clib_net_to_host_u16 (iphdr[23]); + sum += iphdr[22]; + sum += iphdr[23]; case 6: - sum += clib_net_to_host_u16 (iphdr[20]); - sum += clib_net_to_host_u16 (iphdr[21]); + sum += iphdr[20]; + sum += iphdr[21]; case 5: - sum += clib_net_to_host_u16 (iphdr[18]); - sum += clib_net_to_host_u16 (iphdr[19]); + sum += iphdr[18]; + sum += iphdr[19]; case 4: - sum += clib_net_to_host_u16 (iphdr[16]); - sum += clib_net_to_host_u16 (iphdr[17]); + sum += iphdr[16]; + sum += iphdr[17]; case 3: - sum += clib_net_to_host_u16 (iphdr[14]); - sum += clib_net_to_host_u16 (iphdr[15]); + sum += iphdr[14]; + sum += iphdr[15]; case 2: - sum += clib_net_to_host_u16 (iphdr[12]); - sum += clib_net_to_host_u16 (iphdr[13]); + sum += iphdr[12]; + sum += iphdr[13]; case 1: - sum += clib_net_to_host_u16 (iphdr[10]); - sum += clib_net_to_host_u16 (iphdr[11]); + sum += iphdr[10]; + sum += iphdr[11]; default: break; } +#endif sum = ((u16) sum) + (sum >> 16); sum = ((u16) sum) + (sum >> 16); - return clib_host_to_net_u16 (~((u16) sum)); + return ~((u16) sum); } always_inline void -- cgit 1.2.3-korg