From 6f5009c38cafad883212810a2219479a8ff408c0 Mon Sep 17 00:00:00 2001 From: Zhang Chen Date: Tue, 5 Sep 2017 14:31:04 +0800 Subject: net/colo-compare.c: Optimize unpredictable tcp options comparison When network is busy, some tcp options(like sack) will unpredictable occur in primary side or secondary side. it will make packet size not same, but the two packet's payload is identical. colo just care about packet payload, so we skip the option field. Signed-off-by: Zhang Chen Signed-off-by: Jason Wang --- net/colo-compare.c | 39 +++++++++++++++++++++++++++------------ 1 file changed, 27 insertions(+), 12 deletions(-) (limited to 'net/colo-compare.c') diff --git a/net/colo-compare.c b/net/colo-compare.c index 5fe8e3fad9..612fbac72c 100644 --- a/net/colo-compare.c +++ b/net/colo-compare.c @@ -186,7 +186,10 @@ 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, int offset) +static int colo_packet_compare_common(Packet *ppkt, + Packet *spkt, + int poffset, + int soffset) { if (trace_event_get_state_backends(TRACE_COLO_COMPARE_MISCOMPARE)) { char pri_ip_src[20], pri_ip_dst[20], sec_ip_src[20], sec_ip_dst[20]; @@ -201,12 +204,13 @@ static int colo_packet_compare_common(Packet *ppkt, Packet *spkt, int offset) sec_ip_src, sec_ip_dst); } - offset = ppkt->vnet_hdr_len + offset; + poffset = ppkt->vnet_hdr_len + poffset; + soffset = ppkt->vnet_hdr_len + soffset; - if (ppkt->size == spkt->size) { - return memcmp(ppkt->data + offset, - spkt->data + offset, - spkt->size - offset); + if (ppkt->size - poffset == spkt->size - soffset) { + return memcmp(ppkt->data + poffset, + spkt->data + soffset, + spkt->size - soffset); } else { trace_colo_compare_main("Net packet size are not the same"); return -1; @@ -263,13 +267,22 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt) * so we just need skip this field. */ if (ptcp->th_off > 5) { - ptrdiff_t tcp_offset; + ptrdiff_t ptcp_offset, stcp_offset; - tcp_offset = ppkt->transport_header - (uint8_t *)ppkt->data - + (ptcp->th_off * 4) - ppkt->vnet_hdr_len; - res = colo_packet_compare_common(ppkt, spkt, tcp_offset); + ptcp_offset = ppkt->transport_header - (uint8_t *)ppkt->data + + (ptcp->th_off * 4) - ppkt->vnet_hdr_len; + stcp_offset = spkt->transport_header - (uint8_t *)spkt->data + + (stcp->th_off * 4) - spkt->vnet_hdr_len; + + /* + * When network is busy, some tcp options(like sack) will unpredictable + * occur in primary side or secondary side. it will make packet size + * not same, but the two packet's payload is identical. colo just + * care about packet payload, so we skip the option field. + */ + res = colo_packet_compare_common(ppkt, spkt, ptcp_offset, stcp_offset); } else if (ptcp->th_sum == stcp->th_sum) { - res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN); + res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN, ETH_HLEN); } else { res = -1; } @@ -330,6 +343,7 @@ static int colo_packet_compare_udp(Packet *spkt, Packet *ppkt) * the ip payload here. */ ret = colo_packet_compare_common(ppkt, spkt, + network_header_length + ETH_HLEN, network_header_length + ETH_HLEN); if (ret) { @@ -367,6 +381,7 @@ static int colo_packet_compare_icmp(Packet *spkt, Packet *ppkt) * the ip payload here. */ if (colo_packet_compare_common(ppkt, spkt, + network_header_length + ETH_HLEN, network_header_length + ETH_HLEN)) { trace_colo_compare_icmp_miscompare("primary pkt size", ppkt->size); @@ -404,7 +419,7 @@ static int colo_packet_compare_other(Packet *spkt, Packet *ppkt) sec_ip_src, sec_ip_dst); } - return colo_packet_compare_common(ppkt, spkt, 0); + return colo_packet_compare_common(ppkt, spkt, 0, 0); } static int colo_old_packet_check_one(Packet *pkt, int64_t *check_time) -- cgit v1.2.1