rstplib/pcost.c

   1 /************************************************************************
   2  * RSTP library - Rapid Spanning Tree (802.1t, 802.1w)
   3  * Copyright (C) 2001-2003 Optical Access
   4  * Author: Alex Rozin
   5  *
   6  * This file is part of RSTP library.
   7  *
   8  * RSTP library is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by the
  10  * Free Software Foundation; version 2.1
  11  *
  12  * RSTP library is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public License
  18  * along with RSTP library; see the file COPYING.  If not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20  * 02111-1307, USA.
  21  **********************************************************************/
  22
  23 /* Path Cost monitoring state machine */
  24
  25 #include "base.h"
  26 #include "stpm.h"
  27 #include "stp_to.h" /* for STP_OUT_get_port_oper_speed */
  28
  29 #define STATES {        \
  30   CHOOSE(AUTO),         \
  31   CHOOSE(FORSE),        \
  32   CHOOSE(STABLE),       \
  33 }
  34
  35 #define GET_STATE_NAME STP_pcost_get_state_name
  36 #include "choose.h"
  37
  38 static long
  39 computeAutoPCost (STATE_MACH_T *this)
  40 {
  41     long lret;
  42     register PORT_T*  port = this->owner.port;
  43
  44     if (port->usedSpeed        < 10L) {         /* < 10Mb/s */
  45         lret = 20000000;
  46     } else if (port->usedSpeed <= 10L) {        /* 10 Mb/s  */
  47         lret = 2000000;
  48     } else if (port->usedSpeed <= 100L) {       /* 100 Mb/s */
  49         lret = 200000;
  50     } else if (port->usedSpeed <= 1000L) {      /* 1 Gb/s */
  51         lret = 20000;
  52     } else if (port->usedSpeed <= 10000L) {     /* 10 Gb/s */
  53         lret = 2000;
  54     } else if (port->usedSpeed <= 100000L) {    /* 100 Gb/s */
  55         lret = 200;
  56     } else if (port->usedSpeed <= 1000000L) {   /* 1 GTb/s */
  57         lret = 20;
  58     } else if (port->usedSpeed <= 10000000L) {  /* 10 Tb/s */
  59         lret = 2;
  60     } else   /* ??? */                        { /* > Tb/s */
  61         lret = 1;
  62     }
  63 #ifdef STP_DBG
  64     if (port->pcost->debug) {
  65       stp_trace ("usedSpeed=%lu lret=%ld", port->usedSpeed, lret);
  66     }
  67 #endif
  68
  69     return lret;
  70 }
  71
  72 static void
  73 updPortPathCost (PORT_T *port)
  74 {
  75   port->reselect = True;
  76   port->selected = False;
  77 }
  78
  79 void
  80 STP_pcost_enter_state (STATE_MACH_T *this)
  81 {
  82   register PORT_T*  port = this->owner.port;
  83
  84   switch (this->State) {
  85     case BEGIN:
  86       break;
  87     case AUTO:
  88       port->operSpeed = STP_OUT_get_port_oper_speed (port->port_index);
  89 #ifdef STP_DBG
  90       if (port->pcost->debug) {
  91         stp_trace ("AUTO:operSpeed=%lu", port->operSpeed);
  92       }
  93 #endif
  94       port->usedSpeed = port->operSpeed;
  95       port->operPCost = computeAutoPCost (this);
  96       break;
  97     case FORSE:
  98       port->operPCost = port->adminPCost;
  99       port->usedSpeed = -1;
 100       break;
 101     case STABLE:
 102       updPortPathCost (port);
 103       break;
 104   }
 105 }
 106
 107 Bool
 108 STP_pcost_check_conditions (STATE_MACH_T* this)
 109 {
 110   register PORT_T*  port = this->owner.port;
 111
 112   switch (this->State) {
 113     case BEGIN:
 114       return STP_hop_2_state (this, AUTO);
 115     case AUTO:
 116       return STP_hop_2_state (this, STABLE);
 117     case FORSE:
 118       return STP_hop_2_state (this, STABLE);
 119     case STABLE:
 120       if (ADMIN_PORT_PATH_COST_AUTO == port->adminPCost &&
 121           port->operSpeed != port->usedSpeed) {
 122           return STP_hop_2_state (this, AUTO);
 123       }
 124
 125       if (ADMIN_PORT_PATH_COST_AUTO != port->adminPCost &&
 126           port->operPCost != port->adminPCost) {
 127           return STP_hop_2_state (this, FORSE);
 128       }
 129       break;
 130   }
 131   return False;
 132 }
 133