npf_worker.c revision 1.2
1 /* $NetBSD: npf_worker.c,v 1.2 2016/12/26 23:05:06 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2010-2015 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This material is based upon work partially supported by The 8 * NetBSD Foundation under a contract with Mindaugas Rasiukevicius. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #ifdef _KERNEL 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: npf_worker.c,v 1.2 2016/12/26 23:05:06 christos Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/types.h> 38 39 #include <sys/mutex.h> 40 #include <sys/kmem.h> 41 #include <sys/kernel.h> 42 #include <sys/kthread.h> 43 #include <sys/cprng.h> 44 #endif 45 46 #include "npf_impl.h" 47 48 typedef struct npf_worker { 49 kmutex_t worker_lock; 50 kcondvar_t worker_cv; 51 npf_workfunc_t work_funcs[NPF_MAX_WORKS]; 52 bool worker_exit; 53 lwp_t * worker_lwp; 54 npf_t * instances; 55 } npf_worker_t; 56 57 #define W_INTERVAL mstohz(1 * 1000) 58 59 static void npf_worker(void *) __dead; 60 61 static npf_worker_t * npf_workers __read_mostly; 62 static unsigned npf_worker_count __read_mostly; 63 64 int 65 npf_worker_sysinit(unsigned nworkers) 66 { 67 npf_workers = kmem_zalloc(sizeof(npf_worker_t) * nworkers, KM_SLEEP); 68 npf_worker_count = nworkers; 69 70 for (unsigned i = 0; i < nworkers; i++) { 71 npf_worker_t *wrk = &npf_workers[i]; 72 73 mutex_init(&wrk->worker_lock, MUTEX_DEFAULT, IPL_SOFTNET); 74 cv_init(&wrk->worker_cv, "npfgccv"); 75 76 if (kthread_create(PRI_NONE, KTHREAD_MPSAFE | 77 KTHREAD_MUSTJOIN, NULL, npf_worker, wrk, &wrk->worker_lwp, 78 "npfgc-%u", i)) { 79 npf_worker_sysfini(); 80 return ENOMEM; 81 } 82 } 83 return 0; 84 } 85 86 void 87 npf_worker_sysfini(void) 88 { 89 for (unsigned i = 0; i < npf_worker_count; i++) { 90 npf_worker_t *wrk = &npf_workers[i]; 91 92 /* Notify the worker and wait for the exit. */ 93 mutex_enter(&wrk->worker_lock); 94 wrk->worker_exit = true; 95 cv_broadcast(&wrk->worker_cv); 96 mutex_exit(&wrk->worker_lock); 97 98 if (wrk->worker_lwp) { 99 kthread_join(wrk->worker_lwp); 100 } 101 102 /* LWP has exited, destroy the structures. */ 103 cv_destroy(&wrk->worker_cv); 104 mutex_destroy(&wrk->worker_lock); 105 } 106 kmem_free(npf_workers, sizeof(npf_worker_t) * npf_worker_count); 107 } 108 109 void 110 npf_worker_signal(npf_t *npf) 111 { 112 const unsigned idx = npf->worker_id; 113 npf_worker_t *wrk = &npf_workers[idx]; 114 115 mutex_enter(&wrk->worker_lock); 116 cv_signal(&wrk->worker_cv); 117 mutex_exit(&wrk->worker_lock); 118 } 119 120 static bool 121 npf_worker_testset(npf_worker_t *wrk, npf_workfunc_t find, npf_workfunc_t set) 122 { 123 for (u_int i = 0; i < NPF_MAX_WORKS; i++) { 124 if (wrk->work_funcs[i] == find) { 125 wrk->work_funcs[i] = set; 126 return true; 127 } 128 } 129 return false; 130 } 131 132 void 133 npf_worker_register(npf_t *npf, npf_workfunc_t func) 134 { 135 const unsigned idx = cprng_fast32() % npf_worker_count; 136 npf_worker_t *wrk = &npf_workers[idx]; 137 138 mutex_enter(&wrk->worker_lock); 139 140 npf->worker_id = idx; 141 npf->worker_entry = wrk->instances; 142 wrk->instances = npf; 143 144 npf_worker_testset(wrk, NULL, func); 145 mutex_exit(&wrk->worker_lock); 146 } 147 148 void 149 npf_worker_unregister(npf_t *npf, npf_workfunc_t func) 150 { 151 const unsigned idx = npf->worker_id; 152 npf_worker_t *wrk = &npf_workers[idx]; 153 npf_t *instance; 154 155 mutex_enter(&wrk->worker_lock); 156 npf_worker_testset(wrk, func, NULL); 157 if ((instance = wrk->instances) == npf) { 158 wrk->instances = instance->worker_entry; 159 } else while (instance) { 160 if (instance->worker_entry == npf) { 161 instance->worker_entry = npf->worker_entry; 162 break; 163 } 164 instance = instance->worker_entry; 165 } 166 mutex_exit(&wrk->worker_lock); 167 } 168 169 static void 170 npf_worker(void *arg) 171 { 172 npf_worker_t *wrk = arg; 173 174 KASSERT(wrk != NULL); 175 KASSERT(!wrk->worker_exit); 176 177 while (!wrk->worker_exit) { 178 npf_t *npf; 179 180 npf = wrk->instances; 181 while (npf) { 182 u_int i = NPF_MAX_WORKS; 183 npf_workfunc_t work; 184 185 /* Run the jobs. */ 186 while (i--) { 187 if ((work = wrk->work_funcs[i]) != NULL) { 188 work(npf); 189 } 190 } 191 /* Next .. */ 192 npf = npf->worker_entry; 193 } 194 if (wrk->worker_exit) 195 break; 196 197 /* Sleep and periodically wake up, unless we get notified. */ 198 mutex_enter(&wrk->worker_lock); 199 cv_timedwait(&wrk->worker_cv, &wrk->worker_lock, W_INTERVAL); 200 mutex_exit(&wrk->worker_lock); 201 } 202 kthread_exit(0); 203 } 204
Indexes created Mon Sep 22 21:09:42 GMT 2025