From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36771) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d2ycI-0006nu-P2 for qemu-devel@nongnu.org; Tue, 25 Apr 2017 07:26:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d2ycH-0002It-R8 for qemu-devel@nongnu.org; Tue, 25 Apr 2017 07:26:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58900) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1d2ycH-0002IZ-Kh for qemu-devel@nongnu.org; Tue, 25 Apr 2017 07:26:45 -0400 From: Jason Wang Date: Tue, 25 Apr 2017 19:26:07 +0800 Message-Id: <1493119568-15218-8-git-send-email-jasowang@redhat.com> In-Reply-To: <1493119568-15218-1-git-send-email-jasowang@redhat.com> References: <1493119568-15218-1-git-send-email-jasowang@redhat.com> Subject: [Qemu-devel] [PULL V2 7/8] COLO-compare: Optimize tcp compare for option field List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: peter.maydell@linaro.org, qemu-devel@nongnu.org Cc: Zhang Chen , Jason Wang From: Zhang Chen In this patch we support packet that have tcp options field. Add tcp options field check, If the packet have options field we just skip it and compare tcp payload, Avoid unnecessary checkpoint, optimize performance. Signed-off-by: Zhang Chen Signed-off-by: Jason Wang --- net/colo-compare.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/net/colo-compare.c b/net/colo-compare.c index 9b09cfc..4ab80b1 100644 --- a/net/colo-compare.c +++ b/net/colo-compare.c @@ -233,7 +233,32 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet *ppkt) spkt->ip->ip_sum = ppkt->ip->ip_sum; } - if (ptcp->th_sum == stcp->th_sum) { + /* + * Check tcp header length for tcp option field. + * th_off > 5 means this tcp packet have options field. + * The tcp options maybe always different. + * for example: + * From RFC 7323. + * TCP Timestamps option (TSopt): + * Kind: 8 + * + * Length: 10 bytes + * + * +-------+-------+---------------------+---------------------+ + * |Kind=8 | 10 | TS Value (TSval) |TS Echo Reply (TSecr)| + * +-------+-------+---------------------+---------------------+ + * 1 1 4 4 + * + * In this case the primary guest's timestamp always different with + * the secondary guest's timestamp. COLO just focus on payload, + * so we just need skip this field. + */ + if (ptcp->th_off > 5) { + ptrdiff_t tcp_offset; + tcp_offset = ppkt->transport_header - (uint8_t *)ppkt->data + + (ptcp->th_off * 4); + res = colo_packet_compare_common(ppkt, spkt, tcp_offset); + } else if (ptcp->th_sum == stcp->th_sum) { res = colo_packet_compare_common(ppkt, spkt, ETH_HLEN); } else { res = -1; -- 2.7.4