From 6efeb3286dd80c8c943f50fbb5f611d525cd6f8a Mon Sep 17 00:00:00 2001 From: Zhang Chen Date: Thu, 2 Mar 2017 17:54:17 +0800 Subject: [PATCH] COLO-compare: Optimize compare_common and compare_tcp Add offset args for colo_packet_compare_common, optimize colo_packet_compare_icmp() and colo_packet_compare_udp() just compare the IP payload. Before compare all tcp packet, we compare tcp checksum firstly, this function can get better performance. Signed-off-by: Zhang Chen Signed-off-by: Jason Wang --- net/colo-compare.c | 50 ++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 36 insertions(+), 14 deletions(-) diff --git a/net/colo-compare.c b/net/colo-compare.c index 602a758343..9f5968dc0b 100644 --- a/net/colo-compare.c +++ b/net/colo-compare.c @@ -180,7 +180,7 @@ static int packet_enqueue(CompareState *s, int mode) * return: 0 means packet same * > 0 || < 0 means packet different */ -static int colo_packet_compare_common(Packet *ppkt, Packet *spkt) +static int colo_packet_compare_common(Packet *ppkt, Packet *spkt, int offset) { trace_colo_compare_ip_info(ppkt->size, inet_ntoa(ppkt->ip->ip_src), inet_ntoa(ppkt->ip->ip_dst), spkt->size, @@ -188,7 +188,8 @@ static int colo_packet_compare_common(Packet *ppkt, Packet *spkt) inet_ntoa(spkt->ip->ip_dst)); if (ppkt->size == spkt->size) { - return memcmp(ppkt->data, spkt->data, spkt->size); + return memcmp(ppkt->data + offset, spkt->data + offset, + spkt->size - offset); } else { trace_colo_compare_main("Net packet size are not the same"); return -1; @@ -207,13 +208,6 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt) trace_colo_compare_main("compare tcp"); - if (ppkt->size != spkt->size) { - if (trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) { - trace_colo_compare_main("pkt size not same"); - } - return -1; - } - ptcp = (struct tcphdr *)ppkt->transport_header; stcp = (struct tcphdr *)spkt->transport_header; @@ -231,8 +225,11 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt) spkt->ip->ip_sum = ppkt->ip->ip_sum; } - res = memcmp(ppkt->data + ETH_HLEN, spkt->data + ETH_HLEN, - (spkt->size - ETH_HLEN)); + if (ptcp->th_sum == stcp->th_sum) { + res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN); + } else { + res = -1; + } if (res != 0 && trace_event_get_state(TRACE_COLO_COMPARE_MISCOMPARE)) { trace_colo_compare_pkt_info_src(inet_ntoa(ppkt->ip->ip_src), @@ -263,10 +260,22 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt) static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt) { int ret; + int network_header_length = ppkt->ip->ip_hl * 4; trace_colo_compare_main("compare udp"); - ret = colo_packet_compare_common(ppkt, spkt); + /* + * Because of ppkt and spkt are both in the same connection, + * The ppkt's src ip, dst ip, src port, dst port, ip_proto all are + * same with spkt. In addition, IP header's Identification is a random + * field, we can handle it in IP fragmentation function later. + * COLO just concern the response net packet payload from primary guest + * and secondary guest are same or not, So we ignored all IP header include + * other field like TOS,TTL,IP Checksum. we only need to compare + * the ip payload here. + */ + ret = colo_packet_compare_common(ppkt, spkt, + network_header_length + ETH_HLEN); if (ret) { trace_colo_compare_udp_miscompare("primary pkt size", ppkt->size); @@ -284,9 +293,22 @@ static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt) */ static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt) { + int network_header_length = ppkt->ip->ip_hl * 4; + trace_colo_compare_main("compare icmp"); - if (colo_packet_compare_common(ppkt, spkt)) { + /* + * Because of ppkt and spkt are both in the same connection, + * The ppkt's src ip, dst ip, src port, dst port, ip_proto all are + * same with spkt. In addition, IP header's Identification is a random + * field, we can handle it in IP fragmentation function later. + * COLO just concern the response net packet payload from primary guest + * and secondary guest are same or not, So we ignored all IP header include + * other field like TOS,TTL,IP Checksum. we only need to compare + * the ip payload here. + */ + if (colo_packet_compare_common(ppkt, spkt, + network_header_length + ETH_HLEN)) { trace_colo_compare_icmp_miscompare("primary pkt size", ppkt->size); qemu_hexdump((char *)ppkt->data, stderr, "colo-compare", @@ -312,7 +334,7 @@ static int colo_packet_compare_other(Packet *spkt, Packet *ppkt) inet_ntoa(ppkt->ip->ip_dst), spkt->size, inet_ntoa(spkt->ip->ip_src), inet_ntoa(spkt->ip->ip_dst)); - return colo_packet_compare_common(ppkt, spkt); + return colo_packet_compare_common(ppkt, spkt, 0); } static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time) -- 2.11.4.GIT