include/linux/tfrc.h

   1 #ifndef _LINUX_TFRC_H_
   2 #define _LINUX_TFRC_H_
   3 /*
   4  *  TFRC - Data Structures for the TCP-Friendly Rate Control congestion
   5  *         control mechanism as specified in RFC 3448.
   6  *
   7  *  Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
   8  *  Copyright (c) 2005 Ian McDonald <iam4@cs.waikato.ac.nz>
   9  *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
  10  *  Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or
  15  *  (at your option) any later version.
  16  */
  17 #include <linux/types.h>
  18
  19 /**     tfrc_rx_info    -    TFRC Receiver Data Structure
  20  *
  21  *      @tfrcrx_x_recv: receiver estimate of sending rate (3.2.2)
  22  *      @tfrcrx_rtt:    round-trip-time (communicated by sender)
  23  *      @tfrcrx_p:      current estimate of loss event rate (3.2.2)
  24  */
  25 struct tfrc_rx_info {
  26         __u32 tfrcrx_x_recv;
  27         __u32 tfrcrx_rtt;
  28         __u32 tfrcrx_p;
  29 };
  30
  31 /**     tfrc_tx_info    -    TFRC Sender Data Structure
  32  *
  33  *      @tfrctx_x:      computed transmit rate (4.3 (4))
  34  *      @tfrctx_x_recv: receiver estimate of send rate (4.3)
  35  *      @tfrctx_x_calc: return value of throughput equation (3.1)
  36  *      @tfrctx_rtt:    (moving average) estimate of RTT (4.3)
  37  *      @tfrctx_p:      current loss event rate (5.4)
  38  *      @tfrctx_rto:    estimate of RTO, equals 4*RTT (4.3)
  39  *      @tfrctx_ipi:    inter-packet interval (4.6)
  40  *
  41  *  Note: X and X_recv are both maintained in units of 64 * bytes/second. This
  42  *        enables a finer resolution of sending rates and avoids problems with
  43  *        integer arithmetic; u32 is not sufficient as scaling consumes 6 bits.
  44  */
  45 struct tfrc_tx_info {
  46         __u64 tfrctx_x;
  47         __u64 tfrctx_x_recv;
  48         __u32 tfrctx_x_calc;
  49         __u32 tfrctx_rtt;
  50         __u32 tfrctx_p;
  51         __u32 tfrctx_rto;
  52         __u32 tfrctx_ipi;
  53 };
  54
  55 #endif /* _LINUX_TFRC_H_ */