sys/net/altq/altq_classq.h

   1 /*      $KAME: altq_classq.h,v 1.6 2003/01/07 07:33:38 kjc Exp $        */
   2 /*      $DragonFly: src/sys/net/altq/altq_classq.h,v 1.2 2006/09/03 18:52:29 dillon Exp $ */
   3
   4 /*
   5  * Copyright (c) 1991-1997 Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the Network Research
  19  *      Group at Lawrence Berkeley Laboratory.
  20  * 4. Neither the name of the University nor of the Laboratory may be used
  21  *    to endorse or promote products derived from this software without
  22  *    specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36 /*
  37  * class queue definitions extracted from rm_class.h.
  38  */
  39 #ifndef _ALTQ_ALTQ_CLASSQ_H_
  40 #define _ALTQ_ALTQ_CLASSQ_H_
  41
  42 /*
  43  * Packet Queue types: RED or DROPHEAD.
  44  */
  45 #define Q_DROPHEAD      0x00
  46 #define Q_RED           0x01
  47 #define Q_RIO           0x02
  48 #define Q_DROPTAIL      0x03
  49
  50 #ifdef _KERNEL
  51
  52 /*
  53  * Packet Queue structures and macros to manipulate them.
  54  */
  55 struct _class_queue_ {
  56         struct mbuf     *tail_; /* Tail of packet queue */
  57         int     qlen_;          /* Queue length (in number of packets) */
  58         int     qlim_;          /* Queue limit (in number of packets*) */
  59         int     qtype_;         /* Queue type */
  60 };
  61
  62 typedef struct _class_queue_    class_queue_t;
  63
  64 #define qtype(q)        (q)->qtype_             /* Get queue type */
  65 #define qlimit(q)       (q)->qlim_              /* Max packets to be queued */
  66 #define qlen(q)         (q)->qlen_              /* Current queue length. */
  67 #define qtail(q)        (q)->tail_              /* Tail of the queue */
  68 #define qhead(q)        ((q)->tail_ ? (q)->tail_->m_nextpkt : NULL)
  69
  70 #define qempty(q)       ((q)->qlen_ == 0)       /* Is the queue empty?? */
  71 #define q_is_red(q)     ((q)->qtype_ == Q_RED)  /* Is the queue a red queue */
  72 #define q_is_rio(q)     ((q)->qtype_ == Q_RIO)  /* Is the queue a rio queue */
  73 #define q_is_red_or_rio(q)      ((q)->qtype_ == Q_RED || (q)->qtype_ == Q_RIO)
  74
  75 static __inline void
  76 _addq(class_queue_t *q, struct mbuf *m)
  77 {
  78         struct mbuf *m0;
  79
  80         if ((m0 = qtail(q)) != NULL)
  81                 m->m_nextpkt = m0->m_nextpkt;
  82         else
  83                 m0 = m;
  84         m0->m_nextpkt = m;
  85         qtail(q) = m;
  86         qlen(q)++;
  87 }
  88
  89 static __inline struct mbuf *
  90 _getq(class_queue_t *q)
  91 {
  92         struct mbuf  *m, *m0;
  93
  94         if ((m = qtail(q)) == NULL)
  95                 return (NULL);
  96         if ((m0 = m->m_nextpkt) != m)
  97                 m->m_nextpkt = m0->m_nextpkt;
  98         else
  99                 qtail(q) = NULL;
 100         qlen(q)--;
 101         m0->m_nextpkt = NULL;
 102         return (m0);
 103 }
 104
 105 /* drop a packet at the tail of the queue */
 106 static __inline struct mbuf *
 107 _getq_tail(class_queue_t *q)
 108 {
 109         struct mbuf *m, *m0, *prev;
 110
 111         if ((m = m0 = qtail(q)) == NULL)
 112                 return NULL;
 113         do {
 114                 prev = m0;
 115                 m0 = m0->m_nextpkt;
 116         } while (m0 != m);
 117         prev->m_nextpkt = m->m_nextpkt;
 118         if (prev == m)
 119                 qtail(q) = NULL;
 120         else
 121                 qtail(q) = prev;
 122         qlen(q)--;
 123         m->m_nextpkt = NULL;
 124         return (m);
 125 }
 126
 127 /* randomly select a packet in the queue */
 128 static __inline struct mbuf *
 129 _getq_random(class_queue_t *q)
 130 {
 131         struct mbuf *m;
 132         int i, n;
 133
 134         if ((m = qtail(q)) == NULL)
 135                 return NULL;
 136         if (m->m_nextpkt == m)
 137                 qtail(q) = NULL;
 138         else {
 139                 struct mbuf *prev = NULL;
 140
 141                 n = krandom() % qlen(q) + 1;
 142                 for (i = 0; i < n; i++) {
 143                         prev = m;
 144                         m = m->m_nextpkt;
 145                 }
 146                 prev->m_nextpkt = m->m_nextpkt;
 147                 if (m == qtail(q))
 148                         qtail(q) = prev;
 149         }
 150         qlen(q)--;
 151         m->m_nextpkt = NULL;
 152         return (m);
 153 }
 154
 155 static __inline void
 156 _removeq(class_queue_t *q, struct mbuf *m)
 157 {
 158         struct mbuf *m0, *prev;
 159
 160         m0 = qtail(q);
 161         do {
 162                 prev = m0;
 163                 m0 = m0->m_nextpkt;
 164         } while (m0 != m);
 165         prev->m_nextpkt = m->m_nextpkt;
 166         if (prev == m)
 167                 qtail(q) = NULL;
 168         else if (qtail(q) == m)
 169                 qtail(q) = prev;
 170         qlen(q)--;
 171 }
 172
 173 static __inline void
 174 _flushq(class_queue_t *q)
 175 {
 176         struct mbuf *m;
 177
 178         while ((m = _getq(q)) != NULL)
 179                 m_freem(m);
 180 }
 181
 182 #endif /* _KERNEL */
 183
 184 #endif /* _ALTQ_ALTQ_CLASSQ_H_ */