Date: Thu, 29 Jun 2006 10:45:58 -0700 From: "Haisang Wu" <haisang@gmail.com> To: freebsd-net@freebsd.org Subject: Reading m_flags in tcp_output and tcp_input Message-ID: <de1c88480606291045h76f42237kb71f18be1b0f75c2@mail.gmail.com>
next in thread | raw e-mail | index | archive | help
Hello, I need to read m_flags of a mbuf in an TCP application in the following two cases: (1) in sending direction, right before TCP calls ip_output() to send out a packet, (2) in receiving direction, right before TCP appends a packet to so_rcv of the corresponding socket and wakes up the socket. My understandings are: for (1), tcp_output() only calls ip_output() once, so right before that function call, I should read the m_flags. For (2), tcp_input() is more complex and calls insbappendstream_locked() twice, one for fast path processing, and one for slow path processing. I think I should read m_flags before both of the two insbappendstream_locked() function calls. I am using freebsd 5.4. Could you let me know whether my above understandings are correct, and provide some suggestions? Thank you! Haisang
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?de1c88480606291045h76f42237kb71f18be1b0f75c2>