/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2010 Riccardo Panicucci, Luigi Rizzo, Universita` di Pisa * All rights reserved * * 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. * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. */ /* * The API to write a packet scheduling algorithm for dummynet. */ #ifndef _DN_SCHED_H #define _DN_SCHED_H #include <sys/ck.h> #define DN_MULTIQUEUE 0x01 /* * Descriptor for a scheduling algorithm. * Contains all function pointers for a given scheduler * This is typically created when a module is loaded, and stored * in a global list of schedulers. */ struct dn_alg { uint32_t type; /* the scheduler type */ const char *name; /* scheduler name */ uint32_t flags; /* DN_MULTIQUEUE if supports multiple queues */ /* * The following define the size of 3 optional data structures * that may need to be allocated at runtime, and are appended * to each of the base data structures: scheduler, sched.inst, * and queue. We don't have a per-flowset structure. */ /* + parameters attached to the template, e.g. * default queue sizes, weights, quantum size, and so on; */ size_t schk_datalen; /* + per-instance parameters, such as timestamps, * containers for queues, etc; */ size_t si_datalen; size_t q_datalen; /* per-queue parameters (e.g. S,F) */ /* * Methods implemented by the scheduler: * enqueue enqueue packet 'm' on scheduler 's', queue 'q'. * q is NULL for !MULTIQUEUE. * Return 0 on success, 1 on drop (packet consumed anyways). * Note that q should be interpreted only as a hint * on the flow that the mbuf belongs to: while a * scheduler will normally enqueue m into q, it is ok * to leave q alone and put the mbuf elsewhere. * This function is called in two cases: * - when a new packet arrives to the scheduler; * - when a scheduler is reconfigured. In this case the * call is issued by the new_queue callback, with a * non empty queue (q) and m pointing to the first * mbuf in the queue. For this reason, the function * should internally check for (m != q->mq.head) * before calling dn_enqueue(). * * dequeue Called when scheduler instance 's' can * dequeue a packet. Return NULL if none are available. * XXX what about non work-conserving ? * * config called on 'sched X config ...', normally writes * in the area of size sch_arg * * destroy called on 'sched delete', frees everything * in sch_arg (other parts are handled by more specific * functions) * * new_sched called when a new instance is created, e.g. * to create the local queue for !MULTIQUEUE, set V or * copy parameters for WFQ, and so on. * * free_sched called when deleting an instance, cleans * extra data in the per-instance area. * * new_fsk called when a flowset is linked to a scheduler, * e.g. to validate parameters such as weights etc. * free_fsk when a flowset is unlinked from a scheduler. * (probably unnecessary) * * new_queue called to set the per-queue parameters, * e.g. S and F, adjust sum of weights in the parent, etc. * * The new_queue callback is normally called from when * creating a new queue. In some cases (such as a * scheduler change or reconfiguration) it can be called * with a non empty queue. In this case, the queue * In case of non empty queue, the new_queue callback could * need to call the enqueue function. In this case, * the callback should eventually call enqueue() passing * as m the first element in the queue. * * free_queue actions related to a queue removal, e.g. undo * all the above. If the queue has data in it, also remove * from the scheduler. This can e.g. happen during a reconfigure. */ int (*enqueue)(struct dn_sch_inst *, struct dn_queue *, struct mbuf *); struct mbuf * (*dequeue)(struct dn_sch_inst *); int (*config)(struct dn_schk *); int (*destroy)(struct dn_schk*); int (*new_sched)(struct dn_sch_inst *); int (*free_sched)(struct dn_sch_inst *); int (*new_fsk)(struct dn_fsk *f); int (*free_fsk)(struct dn_fsk *f); int (*new_queue)(struct dn_queue *q); int (*free_queue)(struct dn_queue *q); #ifdef NEW_AQM /* Getting scheduler extra parameters */ int (*getconfig)(struct dn_schk *, struct dn_extra_parms *); #endif /* run-time fields */ int ref_count; /* XXX number of instances in the system */ CK_LIST_ENTRY(dn_alg) next; /* Next scheduler in the list */ }; /* MSVC does not support initializers so we need this ugly macro */ #ifdef _WIN32 #define _SI(fld) #else #define _SI(fld) fld #endif /* * Additionally, dummynet exports some functions and macros * to be used by schedulers: */ void dn_free_pkts(struct mbuf *mnext); int dn_enqueue(struct dn_queue *q, struct mbuf* m, int drop); /* bound a variable between min and max */ int ipdn_bound_var(int *v, int dflt, int lo, int hi, const char *msg); /* * Extract the head of a queue, update stats. Must be the very last * thing done on a dequeue as the queue itself may go away. */ static __inline struct mbuf* dn_dequeue(struct dn_queue *q) { struct mbuf *m; next: m = q->mq.head; if (m == NULL) return NULL; #ifdef NEW_AQM /* Call AQM dequeue function */ if (q->fs->aqmfp && q->fs->aqmfp->dequeue ) return q->fs->aqmfp->dequeue(q); #endif q->mq.head = m->m_nextpkt; q->mq.count--; /* Update stats for the queue */ q->ni.length--; q->ni.len_bytes -= m->m_pkthdr.len; if (q->_si) { q->_si->ni.length--; q->_si->ni.len_bytes -= m->m_pkthdr.len; } if (q->ni.length == 0) /* queue is now idle */ q->q_time = V_dn_cfg.curr_time; if (m->m_pkthdr.rcvif != NULL && __predict_false(m_rcvif_restore(m) == NULL)) { m_freem(m); goto next; } return m; } int dn_sched_modevent(module_t mod, int cmd, void *arg); #define DECLARE_DNSCHED_MODULE(name, dnsched) \ static moduledata_t name##_mod = { \ #name, dn_sched_modevent, dnsched \ }; \ DECLARE_MODULE(name, name##_mod, \ SI_SUB_PROTO_FIREWALL, SI_ORDER_ANY); \ MODULE_DEPEND(name, dummynet, 3, 3, 3) #endif /* _DN_SCHED_H */
