kern_cpu.c revision 1.18
1 /* $NetBSD: kern_cpu.c,v 1.18 2008/01/15 03:37:10 rmind Exp $ */ 2 3 /*- 4 * Copyright (c) 2007 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 1.18 2008/01/15 03:37:10 rmind 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 84 #include <uvm/uvm_extern.h> 85 86 void cpuctlattach(int); 87 88 static void cpu_xc_online(struct cpu_info *); 89 static void cpu_xc_offline(struct cpu_info *); 90 91 dev_type_ioctl(cpuctl_ioctl); 92 93 const struct cdevsw cpuctl_cdevsw = { 94 nullopen, nullclose, nullread, nullwrite, cpuctl_ioctl, 95 nullstop, notty, nopoll, nommap, nokqfilter, 96 D_OTHER | D_MPSAFE 97 }; 98 99 kmutex_t cpu_lock; 100 int ncpu; 101 int ncpuonline; 102 bool mp_online; 103 104 static struct cpu_info *cpu_infos[MAXCPUS]; 105 106 int 107 mi_cpu_attach(struct cpu_info *ci) 108 { 109 struct schedstate_percpu *spc = &ci->ci_schedstate; 110 int error; 111 112 ci->ci_index = ncpu; 113 114 mutex_init(&spc->spc_lwplock, MUTEX_DEFAULT, IPL_SCHED); 115 sched_cpuattach(ci); 116 uvm_cpu_attach(ci); 117 118 error = create_idle_lwp(ci); 119 if (error != 0) { 120 /* XXX revert sched_cpuattach */ 121 return error; 122 } 123 124 if (ci == curcpu()) 125 ci->ci_data.cpu_onproc = curlwp; 126 else 127 ci->ci_data.cpu_onproc = ci->ci_data.cpu_idlelwp; 128 129 percpu_init_cpu(ci); 130 softint_init(ci); 131 xc_init_cpu(ci); 132 pool_cache_cpu_init(ci); 133 TAILQ_INIT(&ci->ci_data.cpu_biodone); 134 ncpu++; 135 ncpuonline++; 136 cpu_infos[cpu_index(ci)] = ci; 137 138 return 0; 139 } 140 141 void 142 cpuctlattach(int dummy) 143 { 144 145 } 146 147 int 148 cpuctl_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l) 149 { 150 CPU_INFO_ITERATOR cii; 151 cpustate_t *cs; 152 struct cpu_info *ci; 153 int error, i; 154 u_int id; 155 156 error = 0; 157 158 mutex_enter(&cpu_lock); 159 switch (cmd) { 160 case IOC_CPU_SETSTATE: 161 error = kauth_authorize_generic(l->l_cred, 162 KAUTH_GENERIC_ISSUSER, NULL); 163 if (error != 0) 164 break; 165 cs = data; 166 if ((ci = cpu_lookup(cs->cs_id)) == NULL) { 167 error = ESRCH; 168 break; 169 } 170 if (!cs->cs_intr) { 171 error = EOPNOTSUPP; 172 break; 173 } 174 error = cpu_setonline(ci, cs->cs_online); 175 break; 176 177 case IOC_CPU_GETSTATE: 178 cs = data; 179 id = cs->cs_id; 180 memset(cs, 0, sizeof(*cs)); 181 cs->cs_id = id; 182 if ((ci = cpu_lookup(id)) == NULL) { 183 error = ESRCH; 184 break; 185 } 186 if ((ci->ci_schedstate.spc_flags & SPCF_OFFLINE) != 0) 187 cs->cs_online = false; 188 else 189 cs->cs_online = true; 190 cs->cs_intr = true; 191 cs->cs_lastmod = ci->ci_schedstate.spc_lastmod; 192 break; 193 194 case IOC_CPU_MAPID: 195 i = 0; 196 for (CPU_INFO_FOREACH(cii, ci)) { 197 if (i++ == *(int *)data) 198 break; 199 } 200 if (ci == NULL) 201 error = ESRCH; 202 else 203 *(int *)data = ci->ci_cpuid; 204 break; 205 206 case IOC_CPU_GETCOUNT: 207 *(int *)data = ncpu; 208 break; 209 210 default: 211 error = ENOTTY; 212 break; 213 } 214 mutex_exit(&cpu_lock); 215 216 return error; 217 } 218 219 struct cpu_info * 220 cpu_lookup(cpuid_t id) 221 { 222 CPU_INFO_ITERATOR cii; 223 struct cpu_info *ci; 224 225 for (CPU_INFO_FOREACH(cii, ci)) { 226 if (ci->ci_cpuid == id) 227 return ci; 228 } 229 230 return NULL; 231 } 232 233 struct cpu_info * 234 cpu_lookup_byindex(u_int idx) 235 { 236 struct cpu_info *ci = cpu_infos[idx]; 237 238 KASSERT(idx < MAXCPUS); 239 KASSERT(ci == NULL || cpu_index(ci) == idx); 240 241 return ci; 242 } 243 244 static void 245 cpu_xc_offline(struct cpu_info *ci) 246 { 247 struct schedstate_percpu *spc, *mspc = NULL; 248 struct cpu_info *mci; 249 struct lwp *l; 250 CPU_INFO_ITERATOR cii; 251 int s; 252 253 spc = &ci->ci_schedstate; 254 s = splsched(); 255 spc->spc_flags |= SPCF_OFFLINE; 256 splx(s); 257 258 /* Take the first available CPU for the migration */ 259 for (CPU_INFO_FOREACH(cii, mci)) { 260 mspc = &mci->ci_schedstate; 261 if ((mspc->spc_flags & SPCF_OFFLINE) == 0) 262 break; 263 } 264 KASSERT(mci != NULL); 265 266 /* 267 * Migrate all non-bound threads to the other CPU. 268 * Please note, that this runs from the xcall thread, thus handling 269 * of LSONPROC is not needed. 270 */ 271 mutex_enter(&proclist_lock); 272 273 /* 274 * Note that threads on the runqueue might sleep after this, but 275 * sched_takecpu() would migrate such threads to the appropriate CPU. 276 */ 277 LIST_FOREACH(l, &alllwp, l_list) { 278 lwp_lock(l); 279 if (l->l_cpu == ci && (l->l_stat == LSSLEEP || 280 l->l_stat == LSSTOP || l->l_stat == LSSUSPENDED)) { 281 KASSERT((l->l_flag & LW_RUNNING) == 0); 282 l->l_cpu = mci; 283 } 284 lwp_unlock(l); 285 } 286 287 /* Double-lock the run-queues */ 288 spc_dlock(ci, mci); 289 290 /* Handle LSRUN and LSIDL cases */ 291 LIST_FOREACH(l, &alllwp, l_list) { 292 if (l->l_cpu != ci || (l->l_flag & LW_BOUND)) 293 continue; 294 if (l->l_stat == LSRUN && (l->l_flag & LW_INMEM) != 0) { 295 sched_dequeue(l); 296 l->l_cpu = mci; 297 lwp_setlock(l, mspc->spc_mutex); 298 sched_enqueue(l, false); 299 } else if (l->l_stat == LSRUN || l->l_stat == LSIDL) { 300 l->l_cpu = mci; 301 lwp_setlock(l, mspc->spc_mutex); 302 } 303 } 304 spc_dunlock(ci, mci); 305 mutex_exit(&proclist_lock); 306 } 307 308 static void 309 cpu_xc_online(struct cpu_info *ci) 310 { 311 struct schedstate_percpu *spc; 312 int s; 313 314 spc = &ci->ci_schedstate; 315 s = splsched(); 316 spc->spc_flags &= ~SPCF_OFFLINE; 317 splx(s); 318 } 319 320 int 321 cpu_setonline(struct cpu_info *ci, bool online) 322 { 323 struct schedstate_percpu *spc; 324 CPU_INFO_ITERATOR cii; 325 struct cpu_info *ci2; 326 uint64_t where; 327 xcfunc_t func; 328 int nonline; 329 330 spc = &ci->ci_schedstate; 331 332 KASSERT(mutex_owned(&cpu_lock)); 333 334 if (online) { 335 if ((spc->spc_flags & SPCF_OFFLINE) == 0) 336 return 0; 337 func = (xcfunc_t)cpu_xc_online; 338 ncpuonline++; 339 } else { 340 if ((spc->spc_flags & SPCF_OFFLINE) != 0) 341 return 0; 342 nonline = 0; 343 for (CPU_INFO_FOREACH(cii, ci2)) { 344 nonline += ((ci2->ci_schedstate.spc_flags & 345 SPCF_OFFLINE) == 0); 346 } 347 if (nonline == 1) 348 return EBUSY; 349 func = (xcfunc_t)cpu_xc_offline; 350 ncpuonline--; 351 } 352 353 where = xc_unicast(0, func, ci, NULL, ci); 354 xc_wait(where); 355 if (online) { 356 KASSERT((spc->spc_flags & SPCF_OFFLINE) == 0); 357 } else { 358 KASSERT(spc->spc_flags & SPCF_OFFLINE); 359 } 360 spc->spc_lastmod = time_second; 361 362 return 0; 363 } 364
Indexes created Tue Sep 23 14:10:03 GMT 2025