1 /* $NetBSD: kern_cpu.c,v 1.6 2007/08/18 00:21:10 ad 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 1.6 2007/08/18 00:21:10 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/conf.h> 74 #include <sys/cpu.h> 75 #include <sys/cpuio.h> 76 #include <sys/proc.h> 77 #include <sys/kernel.h> 78 #include <sys/kauth.h> 79 80 #include <uvm/uvm_extern.h> 81 82 void cpuctlattach(int); 83 84 dev_type_ioctl(cpuctl_ioctl); 85 86 const struct cdevsw cpuctl_cdevsw = { 87 nullopen, nullclose, nullread, nullwrite, cpuctl_ioctl, 88 nullstop, notty, nopoll, nommap, nokqfilter, 89 D_OTHER | D_MPSAFE 90 }; 91 92 kmutex_t cpu_lock; 93 94 int 95 mi_cpu_attach(struct cpu_info *ci) 96 { 97 struct schedstate_percpu *spc = &ci->ci_schedstate; 98 int error; 99 100 ci->ci_index = ncpu; 101 102 mutex_init(&spc->spc_lwplock, MUTEX_SPIN, IPL_SCHED); 103 sched_cpuattach(ci); 104 uvm_cpu_attach(ci); 105 106 error = create_idle_lwp(ci); 107 if (error != 0) { 108 /* XXX revert sched_cpuattach */ 109 return error; 110 } 111 112 ncpu++; 113 114 return 0; 115 } 116 117 void 118 cpuctlattach(int dummy) 119 { 120 121 } 122 123 int 124 cpuctl_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l) 125 { 126 CPU_INFO_ITERATOR cii; 127 cpustate_t *cs; 128 struct cpu_info *ci; 129 int error, i; 130 u_int id; 131 132 error = 0; 133 134 mutex_enter(&cpu_lock); 135 switch (cmd) { 136 case IOC_CPU_SETSTATE: 137 error = kauth_authorize_generic(l->l_cred, 138 KAUTH_GENERIC_ISSUSER, NULL); 139 if (error != 0) 140 break; 141 cs = data; 142 if ((ci = cpu_lookup(cs->cs_id)) == NULL) { 143 error = ESRCH; 144 break; 145 } 146 if (!cs->cs_intr) { 147 error = EOPNOTSUPP; 148 break; 149 } 150 error = cpu_setonline(ci, cs->cs_online); 151 break; 152 153 case IOC_CPU_GETSTATE: 154 cs = data; 155 id = cs->cs_id; 156 memset(cs, sizeof(*cs), 0); 157 cs->cs_id = id; 158 if ((ci = cpu_lookup(id)) == NULL) { 159 error = ESRCH; 160 break; 161 } 162 if ((ci->ci_schedstate.spc_flags & SPCF_OFFLINE) != 0) 163 cs->cs_online = false; 164 else 165 cs->cs_online = true; 166 cs->cs_intr = true; 167 cs->cs_lastmod = ci->ci_schedstate.spc_lastmod; 168 break; 169 170 case IOC_CPU_MAPID: 171 i = 0; 172 for (CPU_INFO_FOREACH(cii, ci)) { 173 if (i++ == *(int *)data) 174 break; 175 } 176 if (ci == NULL) 177 error = ESRCH; 178 else 179 *(int *)data = ci->ci_cpuid; 180 break; 181 182 case IOC_CPU_GETCOUNT: 183 *(int *)data = ncpu; 184 break; 185 186 default: 187 error = ENOTTY; 188 break; 189 } 190 mutex_exit(&cpu_lock); 191 192 return error; 193 } 194 195 struct cpu_info * 196 cpu_lookup(cpuid_t id) 197 { 198 CPU_INFO_ITERATOR cii; 199 struct cpu_info *ci; 200 201 for (CPU_INFO_FOREACH(cii, ci)) { 202 if (ci->ci_cpuid == id) 203 return ci; 204 } 205 206 return NULL; 207 } 208 209 int 210 cpu_setonline(struct cpu_info *ci, bool online) 211 { 212 struct schedstate_percpu *spc; 213 CPU_INFO_ITERATOR cii; 214 struct cpu_info *ci2; 215 int nonline; 216 217 spc = &ci->ci_schedstate; 218 219 KASSERT(mutex_owned(&cpu_lock)); 220 221 if (online) { 222 if ((spc->spc_flags & SPCF_OFFLINE) == 0) 223 return 0; 224 spc_lock(ci); 225 spc->spc_flags &= ~SPCF_OFFLINE; 226 cpu_need_resched(ci, true); 227 spc_unlock(ci); 228 spc->spc_lastmod = time_second; 229 } else { 230 if ((spc->spc_flags & SPCF_OFFLINE) != 0) 231 return 0; 232 nonline = 0; 233 for (CPU_INFO_FOREACH(cii, ci2)) { 234 nonline += ((ci2->ci_schedstate.spc_flags & 235 SPCF_OFFLINE) == 0); 236 } 237 if (nonline == 1) 238 return EBUSY; 239 spc_lock(ci); 240 spc->spc_flags |= SPCF_OFFLINE; 241 cpu_need_resched(ci, true); 242 spc_unlock(ci); 243 do { 244 kpause("cpu", false, 1, NULL); 245 #ifdef MULTIPROCESOR 246 } while (ci->ci_curlwp != ci->ci_data.cpu_idlelwp); 247 #else 248 } while (0); 249 #endif 250 spc->spc_lastmod = time_second; 251 } 252 253 return 0; 254 } 255