kern_cpu.c revision 1.24
1 /* $NetBSD: kern_cpu.c,v 1.24 2008/04/11 15:31:34 ad Exp $ */ 2 3 /*- 4 * Copyright (c) 2007, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Andrew Doran. 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /*- 40 * Copyright (c)2007 YAMAMOTO Takashi, 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 */ 64 65 #include <sys/cdefs.h> 66 67 __KERNEL_RCSID(0, "$NetBSD: kern_cpu.c,v 1.24 2008/04/11 15:31:34 ad Exp $"); 68 69 #include <sys/param.h> 70 #include <sys/systm.h> 71 #include <sys/idle.h> 72 #include <sys/sched.h> 73 #include <sys/intr.h> 74 #include <sys/conf.h> 75 #include <sys/cpu.h> 76 #include <sys/cpuio.h> 77 #include <sys/proc.h> 78 #include <sys/percpu.h> 79 #include <sys/kernel.h> 80 #include <sys/kauth.h> 81 #include <sys/xcall.h> 82 #include <sys/pool.h> 83 #include <sys/kmem.h> 84 #include <sys/select.h> 85 #include <sys/namei.h> 86 87 #include <uvm/uvm_extern.h> 88 89 void cpuctlattach(int); 90 91 static void cpu_xc_online(struct cpu_info *); 92 static void cpu_xc_offline(struct cpu_info *); 93 94 dev_type_ioctl(cpuctl_ioctl); 95 96 const struct cdevsw cpuctl_cdevsw = { 97 nullopen, nullclose, nullread, nullwrite, cpuctl_ioctl, 98 nullstop, notty, nopoll, nommap, nokqfilter, 99 D_OTHER | D_MPSAFE 100 }; 101 102 kmutex_t cpu_lock; 103 int ncpu; 104 int ncpuonline; 105 bool mp_online; 106 struct cpuqueue cpu_queue = CIRCLEQ_HEAD_INITIALIZER(cpu_queue); 107 108 static struct cpu_info *cpu_infos[MAXCPUS]; 109 110 int 111 mi_cpu_attach(struct cpu_info *ci) 112 { 113 struct schedstate_percpu *spc = &ci->ci_schedstate; 114 int error; 115 116 ci->ci_index = ncpu; 117 cpu_infos[cpu_index(ci)] = ci; 118 CIRCLEQ_INSERT_TAIL(&cpu_queue, ci, ci_data.cpu_qchain); 119 120 KASSERT(sizeof(kmutex_t) <= CACHE_LINE_SIZE); 121 spc->spc_lwplock = kmem_alloc(CACHE_LINE_SIZE, KM_SLEEP); 122 mutex_init(spc->spc_lwplock, MUTEX_DEFAULT, IPL_SCHED); 123 sched_cpuattach(ci); 124 uvm_cpu_attach(ci); 125 126 error = create_idle_lwp(ci); 127 if (error != 0) { 128 /* XXX revert sched_cpuattach */ 129 return error; 130 } 131 132 if (ci == curcpu()) 133 ci->ci_data.cpu_onproc = curlwp; 134 else 135 ci->ci_data.cpu_onproc = ci->ci_data.cpu_idlelwp; 136 137 percpu_init_cpu(ci); 138 softint_init(ci); 139 xc_init_cpu(ci); 140 pool_cache_cpu_init(ci); 141 selsysinit(ci); 142 cache_cpu_init(ci); 143 TAILQ_INIT(&ci->ci_data.cpu_biodone); 144 ncpu++; 145 ncpuonline++; 146 147 return 0; 148 } 149 150 void 151 cpuctlattach(int dummy) 152 { 153 154 } 155 156 int 157 cpuctl_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l) 158 { 159 CPU_INFO_ITERATOR cii; 160 cpustate_t *cs; 161 struct cpu_info *ci; 162 int error, i; 163 u_int id; 164 165 error = 0; 166 167 mutex_enter(&cpu_lock); 168 switch (cmd) { 169 case IOC_CPU_SETSTATE: 170 cs = data; 171 error = kauth_authorize_system(l->l_cred, 172 KAUTH_SYSTEM_CPU, KAUTH_REQ_SYSTEM_CPU_SETSTATE, cs, NULL, 173 NULL); 174 if (error != 0) 175 break; 176 if ((ci = cpu_lookup(cs->cs_id)) == NULL) { 177 error = ESRCH; 178 break; 179 } 180 if (!cs->cs_intr) { 181 error = EOPNOTSUPP; 182 break; 183 } 184 error = cpu_setonline(ci, cs->cs_online); 185 break; 186 187 case IOC_CPU_GETSTATE: 188 cs = data; 189 id = cs->cs_id; 190 memset(cs, 0, sizeof(*cs)); 191 cs->cs_id = id; 192 if ((ci = cpu_lookup(id)) == NULL) { 193 error = ESRCH; 194 break; 195 } 196 if ((ci->ci_schedstate.spc_flags & SPCF_OFFLINE) != 0) 197 cs->cs_online = false; 198 else 199 cs->cs_online = true; 200 cs->cs_intr = true; 201 cs->cs_lastmod = ci->ci_schedstate.spc_lastmod; 202 break; 203 204 case IOC_CPU_MAPID: 205 i = 0; 206 for (CPU_INFO_FOREACH(cii, ci)) { 207 if (i++ == *(int *)data) 208 break; 209 } 210 if (ci == NULL) 211 error = ESRCH; 212 else 213 *(int *)data = ci->ci_cpuid; 214 break; 215 216 case IOC_CPU_GETCOUNT: 217 *(int *)data = ncpu; 218 break; 219 220 default: 221 error = ENOTTY; 222 break; 223 } 224 mutex_exit(&cpu_lock); 225 226 return error; 227 } 228 229 struct cpu_info * 230 cpu_lookup(cpuid_t id) 231 { 232 CPU_INFO_ITERATOR cii; 233 struct cpu_info *ci; 234 235 for (CPU_INFO_FOREACH(cii, ci)) { 236 if (ci->ci_cpuid == id) 237 return ci; 238 } 239 240 return NULL; 241 } 242 243 struct cpu_info * 244 cpu_lookup_byindex(u_int idx) 245 { 246 struct cpu_info *ci = cpu_infos[idx]; 247 248 KASSERT(idx < MAXCPUS); 249 KASSERT(ci == NULL || cpu_index(ci) == idx); 250 251 return ci; 252 } 253 254 static void 255 cpu_xc_offline(struct cpu_info *ci) 256 { 257 struct schedstate_percpu *spc, *mspc = NULL; 258 struct cpu_info *mci; 259 struct lwp *l; 260 CPU_INFO_ITERATOR cii; 261 int s; 262 263 spc = &ci->ci_schedstate; 264 s = splsched(); 265 spc->spc_flags |= SPCF_OFFLINE; 266 splx(s); 267 268 /* Take the first available CPU for the migration */ 269 for (CPU_INFO_FOREACH(cii, mci)) { 270 mspc = &mci->ci_schedstate; 271 if ((mspc->spc_flags & SPCF_OFFLINE) == 0) 272 break; 273 } 274 KASSERT(mci != NULL); 275 276 /* 277 * Migrate all non-bound threads to the other CPU. 278 * Please note, that this runs from the xcall thread, thus handling 279 * of LSONPROC is not needed. 280 */ 281 mutex_enter(&proclist_lock); 282 283 /* 284 * Note that threads on the runqueue might sleep after this, but 285 * sched_takecpu() would migrate such threads to the appropriate CPU. 286 */ 287 LIST_FOREACH(l, &alllwp, l_list) { 288 lwp_lock(l); 289 if (l->l_cpu == ci && (l->l_stat == LSSLEEP || 290 l->l_stat == LSSTOP || l->l_stat == LSSUSPENDED)) { 291 KASSERT((l->l_flag & LW_RUNNING) == 0); 292 l->l_cpu = mci; 293 } 294 lwp_unlock(l); 295 } 296 297 /* Double-lock the run-queues */ 298 spc_dlock(ci, mci); 299 300 /* Handle LSRUN and LSIDL cases */ 301 LIST_FOREACH(l, &alllwp, l_list) { 302 if (l->l_cpu != ci || (l->l_flag & LW_BOUND)) 303 continue; 304 if (l->l_stat == LSRUN && (l->l_flag & LW_INMEM) != 0) { 305 sched_dequeue(l); 306 l->l_cpu = mci; 307 lwp_setlock(l, mspc->spc_mutex); 308 sched_enqueue(l, false); 309 } else if (l->l_stat == LSRUN || l->l_stat == LSIDL) { 310 l->l_cpu = mci; 311 lwp_setlock(l, mspc->spc_mutex); 312 } 313 } 314 spc_dunlock(ci, mci); 315 mutex_exit(&proclist_lock); 316 317 #ifdef __HAVE_MD_CPU_OFFLINE 318 cpu_offline_md(); 319 #endif 320 } 321 322 static void 323 cpu_xc_online(struct cpu_info *ci) 324 { 325 struct schedstate_percpu *spc; 326 int s; 327 328 spc = &ci->ci_schedstate; 329 s = splsched(); 330 spc->spc_flags &= ~SPCF_OFFLINE; 331 splx(s); 332 } 333 334 int 335 cpu_setonline(struct cpu_info *ci, bool online) 336 { 337 struct schedstate_percpu *spc; 338 CPU_INFO_ITERATOR cii; 339 struct cpu_info *ci2; 340 uint64_t where; 341 xcfunc_t func; 342 int nonline; 343 344 spc = &ci->ci_schedstate; 345 346 KASSERT(mutex_owned(&cpu_lock)); 347 348 if (online) { 349 if ((spc->spc_flags & SPCF_OFFLINE) == 0) 350 return 0; 351 func = (xcfunc_t)cpu_xc_online; 352 ncpuonline++; 353 } else { 354 if ((spc->spc_flags & SPCF_OFFLINE) != 0) 355 return 0; 356 nonline = 0; 357 for (CPU_INFO_FOREACH(cii, ci2)) { 358 nonline += ((ci2->ci_schedstate.spc_flags & 359 SPCF_OFFLINE) == 0); 360 } 361 if (nonline == 1) 362 return EBUSY; 363 func = (xcfunc_t)cpu_xc_offline; 364 ncpuonline--; 365 } 366 367 where = xc_unicast(0, func, ci, NULL, ci); 368 xc_wait(where); 369 if (online) { 370 KASSERT((spc->spc_flags & SPCF_OFFLINE) == 0); 371 } else { 372 KASSERT(spc->spc_flags & SPCF_OFFLINE); 373 } 374 spc->spc_lastmod = time_second; 375 376 return 0; 377 } 378
Indexes created Tue Sep 23 02:09:52 GMT 2025