1 /* $NetBSD: intr.c,v 1.34 2010/09/07 18:25:38 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2008 Antti Kantee. All Rights Reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __KERNEL_RCSID(0, "$NetBSD: intr.c,v 1.34 2010/09/07 18:25:38 pooka Exp $"); 30 31 #include <sys/param.h> 32 #include <sys/atomic.h> 33 #include <sys/cpu.h> 34 #include <sys/kernel.h> 35 #include <sys/kmem.h> 36 #include <sys/kthread.h> 37 #include <sys/malloc.h> 38 #include <sys/intr.h> 39 #include <sys/timetc.h> 40 41 #include <rump/rumpuser.h> 42 43 #include "rump_private.h" 44 45 /* 46 * Interrupt simulator. It executes hardclock() and softintrs. 47 */ 48 49 #define SI_MPSAFE 0x01 50 #define SI_KILLME 0x02 51 52 struct softint_percpu; 53 struct softint { 54 void (*si_func)(void *); 55 void *si_arg; 56 int si_flags; 57 int si_level; 58 59 struct softint_percpu *si_entry; /* [0,ncpu-1] */ 60 }; 61 62 struct softint_percpu { 63 struct softint *sip_parent; 64 bool sip_onlist; 65 66 LIST_ENTRY(softint_percpu) sip_entries; 67 }; 68 69 struct softint_lev { 70 struct rumpuser_cv *si_cv; 71 LIST_HEAD(, softint_percpu) si_pending; 72 }; 73 74 kcondvar_t lbolt; /* Oh Kath Ra */ 75 76 static u_int ticks; 77 static int ncpu_final; 78 79 static u_int 80 rumptc_get(struct timecounter *tc) 81 { 82 83 KASSERT(rump_threads); 84 return ticks; 85 } 86 87 static struct timecounter rumptc = { 88 .tc_get_timecount = rumptc_get, 89 .tc_poll_pps = NULL, 90 .tc_counter_mask = ~0, 91 .tc_frequency = 0, 92 .tc_name = "rumpclk", 93 .tc_quality = 0, 94 }; 95 96 /* 97 * clock "interrupt" 98 */ 99 static void 100 doclock(void *noarg) 101 { 102 struct timespec clockbase, clockup; 103 struct timespec thetick, curtime; 104 struct rumpuser_cv *clockcv; 105 struct rumpuser_mtx *clockmtx; 106 uint64_t sec, nsec; 107 int error; 108 extern int hz; 109 110 memset(&clockup, 0, sizeof(clockup)); 111 rumpuser_gettime(&sec, &nsec, &error); 112 clockbase.tv_sec = sec; 113 clockbase.tv_nsec = nsec; 114 curtime = clockbase; 115 thetick.tv_sec = 0; 116 thetick.tv_nsec = 1000000000/hz; 117 118 /* XXX: dummies */ 119 rumpuser_cv_init(&clockcv); 120 rumpuser_mutex_init(&clockmtx); 121 122 rumpuser_mutex_enter(clockmtx); 123 for (;;) { 124 callout_hardclock(); 125 126 /* wait until the next tick. XXX: what if the clock changes? */ 127 while (rumpuser_cv_timedwait(clockcv, clockmtx, 128 curtime.tv_sec, curtime.tv_nsec) == 0) 129 continue; 130 131 /* XXX: sync with a) virtual clock b) host clock */ 132 timespecadd(&clockup, &clockbase, &curtime); 133 timespecadd(&clockup, &thetick, &clockup); 134 135 #if 0 136 /* CPU_IS_PRIMARY is MD and hence unreliably correct here */ 137 if (!CPU_IS_PRIMARY(curcpu())) 138 continue; 139 #else 140 if (curcpu()->ci_index != 0) 141 continue; 142 #endif 143 144 if ((++ticks % hz) == 0) { 145 cv_broadcast(&lbolt); 146 } 147 tc_ticktock(); 148 } 149 } 150 151 /* 152 * Soft interrupt execution thread. This thread is pinned to the 153 * same CPU that scheduled the interrupt, so we don't need to do 154 * lock against si_lvl. 155 */ 156 static void 157 sithread(void *arg) 158 { 159 struct softint_percpu *sip; 160 struct softint *si; 161 void (*func)(void *) = NULL; 162 void *funarg; 163 bool mpsafe; 164 int mylevel = (uintptr_t)arg; 165 struct softint_lev *si_lvlp, *si_lvl; 166 struct cpu_data *cd = &curcpu()->ci_data; 167 168 si_lvlp = cd->cpu_softcpu; 169 si_lvl = &si_lvlp[mylevel]; 170 171 for (;;) { 172 if (!LIST_EMPTY(&si_lvl->si_pending)) { 173 sip = LIST_FIRST(&si_lvl->si_pending); 174 si = sip->sip_parent; 175 176 func = si->si_func; 177 funarg = si->si_arg; 178 mpsafe = si->si_flags & SI_MPSAFE; 179 180 sip->sip_onlist = false; 181 LIST_REMOVE(sip, sip_entries); 182 if (si->si_flags & SI_KILLME) { 183 softint_disestablish(si); 184 continue; 185 } 186 } else { 187 rump_schedlock_cv_wait(si_lvl->si_cv); 188 continue; 189 } 190 191 if (!mpsafe) 192 KERNEL_LOCK(1, curlwp); 193 func(funarg); 194 if (!mpsafe) 195 KERNEL_UNLOCK_ONE(curlwp); 196 } 197 198 panic("sithread unreachable"); 199 } 200 201 void 202 rump_intr_init(int numcpu) 203 { 204 205 cv_init(&lbolt, "oh kath ra"); 206 ncpu_final = numcpu; 207 } 208 209 void 210 softint_init(struct cpu_info *ci) 211 { 212 struct cpu_data *cd = &ci->ci_data; 213 struct softint_lev *slev; 214 int rv, i; 215 216 if (!rump_threads) 217 return; 218 219 /* XXX */ 220 if (ci->ci_index == 0) { 221 rumptc.tc_frequency = hz; 222 tc_init(&rumptc); 223 } 224 225 slev = kmem_alloc(sizeof(struct softint_lev) * SOFTINT_COUNT, KM_SLEEP); 226 for (i = 0; i < SOFTINT_COUNT; i++) { 227 rumpuser_cv_init(&slev[i].si_cv); 228 LIST_INIT(&slev[i].si_pending); 229 } 230 cd->cpu_softcpu = slev; 231 232 /* softint might run on different physical CPU */ 233 membar_sync(); 234 235 for (i = 0; i < SOFTINT_COUNT; i++) { 236 rv = kthread_create(PRI_NONE, 237 KTHREAD_MPSAFE | KTHREAD_INTR, ci, 238 sithread, (void *)(uintptr_t)i, 239 NULL, "rsi%d/%d", ci->ci_index, i); 240 } 241 242 rv = kthread_create(PRI_NONE, KTHREAD_MPSAFE, 243 ci, doclock, NULL, NULL, "rumpclk%d", ci->ci_index); 244 if (rv) 245 panic("clock thread creation failed: %d", rv); 246 } 247 248 void * 249 softint_establish(u_int flags, void (*func)(void *), void *arg) 250 { 251 struct softint *si; 252 struct softint_percpu *sip; 253 int i; 254 255 si = malloc(sizeof(*si), M_TEMP, M_WAITOK); 256 si->si_func = func; 257 si->si_arg = arg; 258 si->si_flags = flags & SOFTINT_MPSAFE ? SI_MPSAFE : 0; 259 si->si_level = flags & SOFTINT_LVLMASK; 260 KASSERT(si->si_level < SOFTINT_COUNT); 261 si->si_entry = malloc(sizeof(*si->si_entry) * ncpu_final, 262 M_TEMP, M_WAITOK | M_ZERO); 263 for (i = 0; i < ncpu_final; i++) { 264 sip = &si->si_entry[i]; 265 sip->sip_parent = si; 266 } 267 268 return si; 269 } 270 271 /* 272 * Soft interrupts bring two choices. If we are running with thread 273 * support enabled, defer execution, otherwise execute in place. 274 */ 275 276 void 277 softint_schedule(void *arg) 278 { 279 struct softint *si = arg; 280 struct softint_percpu *sip = &si->si_entry[curcpu()->ci_index]; 281 struct cpu_data *cd = &curcpu()->ci_data; 282 struct softint_lev *si_lvl = cd->cpu_softcpu; 283 284 if (!rump_threads) { 285 si->si_func(si->si_arg); 286 } else { 287 if (!sip->sip_onlist) { 288 LIST_INSERT_HEAD(&si_lvl[si->si_level].si_pending, 289 sip, sip_entries); 290 sip->sip_onlist = true; 291 } 292 } 293 } 294 295 /* 296 * flimsy disestablish: should wait for softints to finish. 297 */ 298 void 299 softint_disestablish(void *cook) 300 { 301 struct softint *si = cook; 302 int i; 303 304 for (i = 0; i < ncpu_final; i++) { 305 struct softint_percpu *sip; 306 307 sip = &si->si_entry[i]; 308 if (sip->sip_onlist) { 309 si->si_flags |= SI_KILLME; 310 return; 311 } 312 } 313 free(si->si_entry, M_TEMP); 314 free(si, M_TEMP); 315 } 316 317 void 318 rump_softint_run(struct cpu_info *ci) 319 { 320 struct cpu_data *cd = &ci->ci_data; 321 struct softint_lev *si_lvl = cd->cpu_softcpu; 322 int i; 323 324 if (!rump_threads) 325 return; 326 327 for (i = 0; i < SOFTINT_COUNT; i++) { 328 if (!LIST_EMPTY(&si_lvl[i].si_pending)) 329 rumpuser_cv_signal(si_lvl[i].si_cv); 330 } 331 } 332 333 bool 334 cpu_intr_p(void) 335 { 336 337 return false; 338 } 339 340 bool 341 cpu_softintr_p(void) 342 { 343 344 return curlwp->l_pflag & LP_INTR; 345 } 346