FreeBSD/Linux Kernel Cross Reference
sys/net/altq/altq_codel.h

     /*
      * CoDel - The Controlled-Delay Active Queue Management algorithm
      *
      *  Copyright (C) 2013 Ermal Luçi <eri@FreeBSD.org>
      *  Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
      *  Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
      *  Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
      *  Copyright (C) 2012 Eric Dumazet <edumazet@google.com>
      *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions, and the following disclaimer,
     *    without modification.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. The names of the authors may not be used to endorse or promote products
     *    derived from this software without specific prior written permission.
     *
     * Alternatively, provided that this notice is retained in full, this
     * software may be distributed under the terms of the GNU General
     * Public License ("GPL") version 2, in which case the provisions of the
     * GPL apply INSTEAD OF those given above.
     *
     * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
     * DAMAGE.
     *
     * $FreeBSD$
     */
    
    #ifndef _ALTQ_ALTQ_CODEL_H_
    #define _ALTQ_ALTQ_CODEL_H_
    
    struct codel_stats {
            u_int32_t       maxpacket;
            struct pktcntr  drop_cnt;
            u_int           marked_packets;
    };
    
    struct codel_ifstats {
            u_int                   qlength;
            u_int                   qlimit;
            struct codel_stats      stats;
            struct pktcntr  cl_xmitcnt;     /* transmitted packet counter */
            struct pktcntr  cl_dropcnt;     /* dropped packet counter */
    };
    
    /*
     * CBQ_STATS_VERSION is defined in altq.h to work around issues stemming
     * from mixing of public-API and internal bits in each scheduler-specific
     * header.
     */
    
    #ifdef _KERNEL
    #include <net/altq/altq_classq.h>
    
    /**
     * struct codel_params - contains codel parameters
     *  <at> target:        target queue size (in time units)
     *  <at> interval:      width of moving time window
     *  <at> ecn:   is Explicit Congestion Notification enabled
     */
    struct codel_params {
            u_int64_t       target;
            u_int64_t       interval;
            int             ecn;
    };
    
    /**
     * struct codel_vars - contains codel variables
     *  <at> count:         how many drops we've done since the last time we
     *                      entered dropping state
     *  <at> lastcount:     count at entry to dropping state
     *  <at> dropping:      set to true if in dropping state
     *  <at> rec_inv_sqrt:  reciprocal value of sqrt(count) >> 1
     *  <at> first_above_time:      when we went (or will go) continuously above
     *                              target for interval
     *  <at> drop_next:     time to drop next packet, or when we dropped last
     *  <at> ldelay:        sojourn time of last dequeued packet
     */
    struct codel_vars {
            u_int32_t       count;
            u_int32_t       lastcount;
            int             dropping;
            u_int16_t       rec_inv_sqrt;
            u_int64_t       first_above_time;
            u_int64_t       drop_next;
           u_int64_t       ldelay;
   };
           
   struct codel {
           int                     last_pps;
           struct codel_params     params;
           struct codel_vars       vars;
           struct codel_stats      stats;
           struct timeval          last_log;
           u_int32_t               drop_overlimit;
   };
   
   /*
    * codel interface state
    */
   struct codel_if {
           struct codel_if         *cif_next;      /* interface state list */
           struct ifaltq           *cif_ifq;       /* backpointer to ifaltq */
           u_int                   cif_bandwidth;  /* link bandwidth in bps */
   
           class_queue_t   *cl_q;          /* class queue structure */
           struct codel    codel;
   
           /* statistics */
           struct codel_ifstats cl_stats;
   };
   
   struct codel    *codel_alloc(int, int, int);
   void             codel_destroy(struct codel *);
   int              codel_addq(struct codel *, class_queue_t *, struct mbuf *);
   struct mbuf     *codel_getq(struct codel *, class_queue_t *);
   void             codel_getstats(struct codel *, struct codel_stats *);
   
   #endif /* _KERNEL */
   
   #endif /* _ALTQ_ALTQ_CODEL_H_ */

Cache object: 2155da2674329b61dde3774d3bb5ac32