cpus.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 /* Needed early for CONFIG_BSD etc. */
  26 #include "config-host.h"
  27
  28 #include "monitor.h"
  29 #include "sysemu.h"
  30 #include "gdbstub.h"
  31 #include "dma.h"
  32 #include "kvm.h"
  33 #include "exec-all.h"
  34
  35 #include "cpus.h"
  36
  37 #ifdef SIGRTMIN
  38 #define SIG_IPI (SIGRTMIN+4)
  39 #else
  40 #define SIG_IPI SIGUSR1
  41 #endif
  42
  43 static CPUState *cur_cpu;
  44 static CPUState *next_cpu;
  45
  46 /***********************************************************/
  47 void hw_error(const char *fmt, ...)
  48 {
  49     va_list ap;
  50     CPUState *env;
  51
  52     va_start(ap, fmt);
  53     fprintf(stderr, "qemu: hardware error: ");
  54     vfprintf(stderr, fmt, ap);
  55     fprintf(stderr, "\n");
  56     for(env = first_cpu; env != NULL; env = env->next_cpu) {
  57         fprintf(stderr, "CPU #%d:\n", env->cpu_index);
  58 #ifdef TARGET_I386
  59         cpu_dump_state(env, stderr, fprintf, X86_DUMP_FPU);
  60 #else
  61         cpu_dump_state(env, stderr, fprintf, 0);
  62 #endif
  63     }
  64     va_end(ap);
  65     abort();
  66 }
  67
  68 void cpu_synchronize_all_states(void)
  69 {
  70     CPUState *cpu;
  71
  72     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  73         cpu_synchronize_state(cpu);
  74     }
  75 }
  76
  77 void cpu_synchronize_all_post_reset(void)
  78 {
  79     CPUState *cpu;
  80
  81     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  82         cpu_synchronize_post_reset(cpu);
  83     }
  84 }
  85
  86 void cpu_synchronize_all_post_init(void)
  87 {
  88     CPUState *cpu;
  89
  90     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  91         cpu_synchronize_post_init(cpu);
  92     }
  93 }
  94
  95 int cpu_is_stopped(CPUState *env)
  96 {
  97     return !vm_running || env->stopped;
  98 }
  99
 100 static void do_vm_stop(int reason)
 101 {
 102     if (vm_running) {
 103         cpu_disable_ticks();
 104         vm_running = 0;
 105         pause_all_vcpus();
 106         vm_state_notify(0, reason);
 107         monitor_protocol_event(QEVENT_STOP, NULL);
 108     }
 109 }
 110
 111 static int cpu_can_run(CPUState *env)
 112 {
 113     if (env->stop)
 114         return 0;
 115     if (env->stopped || !vm_running)
 116         return 0;
 117     return 1;
 118 }
 119
 120 static int cpu_has_work(CPUState *env)
 121 {
 122     if (env->stop)
 123         return 1;
 124     if (env->queued_work_first)
 125         return 1;
 126     if (env->stopped || !vm_running)
 127         return 0;
 128     if (!env->halted)
 129         return 1;
 130     if (qemu_cpu_has_work(env))
 131         return 1;
 132     return 0;
 133 }
 134
 135 static int tcg_has_work(void)
 136 {
 137     CPUState *env;
 138
 139     for (env = first_cpu; env != NULL; env = env->next_cpu)
 140         if (cpu_has_work(env))
 141             return 1;
 142     return 0;
 143 }
 144
 145 #ifndef _WIN32
 146 static int io_thread_fd = -1;
 147
 148 static void qemu_event_increment(void)
 149 {
 150     /* Write 8 bytes to be compatible with eventfd.  */
 151     static const uint64_t val = 1;
 152     ssize_t ret;
 153
 154     if (io_thread_fd == -1)
 155         return;
 156
 157     do {
 158         ret = write(io_thread_fd, &val, sizeof(val));
 159     } while (ret < 0 && errno == EINTR);
 160
 161     /* EAGAIN is fine, a read must be pending.  */
 162     if (ret < 0 && errno != EAGAIN) {
 163         fprintf(stderr, "qemu_event_increment: write() filed: %s\n",
 164                 strerror(errno));
 165         exit (1);
 166     }
 167 }
 168
 169 static void qemu_event_read(void *opaque)
 170 {
 171     int fd = (unsigned long)opaque;
 172     ssize_t len;
 173     char buffer[512];
 174
 175     /* Drain the notify pipe.  For eventfd, only 8 bytes will be read.  */
 176     do {
 177         len = read(fd, buffer, sizeof(buffer));
 178     } while ((len == -1 && errno == EINTR) || len == sizeof(buffer));
 179 }
 180
 181 static int qemu_event_init(void)
 182 {
 183     int err;
 184     int fds[2];
 185
 186     err = qemu_eventfd(fds);
 187     if (err == -1)
 188         return -errno;
 189
 190     err = fcntl_setfl(fds[0], O_NONBLOCK);
 191     if (err < 0)
 192         goto fail;
 193
 194     err = fcntl_setfl(fds[1], O_NONBLOCK);
 195     if (err < 0)
 196         goto fail;
 197
 198     qemu_set_fd_handler2(fds[0], NULL, qemu_event_read, NULL,
 199                          (void *)(unsigned long)fds[0]);
 200
 201     io_thread_fd = fds[1];
 202     return 0;
 203
 204 fail:
 205     close(fds[0]);
 206     close(fds[1]);
 207     return err;
 208 }
 209 #else
 210 HANDLE qemu_event_handle;
 211
 212 static void dummy_event_handler(void *opaque)
 213 {
 214 }
 215
 216 static int qemu_event_init(void)
 217 {
 218     qemu_event_handle = CreateEvent(NULL, FALSE, FALSE, NULL);
 219     if (!qemu_event_handle) {
 220         fprintf(stderr, "Failed CreateEvent: %ld\n", GetLastError());
 221         return -1;
 222     }
 223     qemu_add_wait_object(qemu_event_handle, dummy_event_handler, NULL);
 224     return 0;
 225 }
 226
 227 static void qemu_event_increment(void)
 228 {
 229     if (!SetEvent(qemu_event_handle)) {
 230         fprintf(stderr, "qemu_event_increment: SetEvent failed: %ld\n",
 231                 GetLastError());
 232         exit (1);
 233     }
 234 }
 235 #endif
 236
 237 #ifndef CONFIG_IOTHREAD
 238 int qemu_init_main_loop(void)
 239 {
 240     return qemu_event_init();
 241 }
 242
 243 void qemu_main_loop_start(void)
 244 {
 245 }
 246
 247 void qemu_init_vcpu(void *_env)
 248 {
 249     CPUState *env = _env;
 250
 251     env->nr_cores = smp_cores;
 252     env->nr_threads = smp_threads;
 253     if (kvm_enabled())
 254         kvm_init_vcpu(env);
 255     return;
 256 }
 257
 258 int qemu_cpu_self(void *env)
 259 {
 260     return 1;
 261 }
 262
 263 void run_on_cpu(CPUState *env, void (*func)(void *data), void *data)
 264 {
 265     func(data);
 266 }
 267
 268 void resume_all_vcpus(void)
 269 {
 270 }
 271
 272 void pause_all_vcpus(void)
 273 {
 274 }
 275
 276 void qemu_cpu_kick(void *env)
 277 {
 278     return;
 279 }
 280
 281 void qemu_notify_event(void)
 282 {
 283     CPUState *env = cpu_single_env;
 284
 285     qemu_event_increment ();
 286     if (env) {
 287         cpu_exit(env);
 288     }
 289     if (next_cpu && env != next_cpu) {
 290         cpu_exit(next_cpu);
 291     }
 292 }
 293
 294 void qemu_mutex_lock_iothread(void) {}
 295 void qemu_mutex_unlock_iothread(void) {}
 296
 297 void vm_stop(int reason)
 298 {
 299     do_vm_stop(reason);
 300 }
 301
 302 #else /* CONFIG_IOTHREAD */
 303
 304 #include "qemu-thread.h"
 305
 306 QemuMutex qemu_global_mutex;
 307 static QemuMutex qemu_fair_mutex;
 308
 309 static QemuThread io_thread;
 310
 311 static QemuThread *tcg_cpu_thread;
 312 static QemuCond *tcg_halt_cond;
 313
 314 static int qemu_system_ready;
 315 /* cpu creation */
 316 static QemuCond qemu_cpu_cond;
 317 /* system init */
 318 static QemuCond qemu_system_cond;
 319 static QemuCond qemu_pause_cond;
 320 static QemuCond qemu_work_cond;
 321
 322 static void tcg_init_ipi(void);
 323 static void kvm_init_ipi(CPUState *env);
 324 static void unblock_io_signals(void);
 325
 326 int qemu_init_main_loop(void)
 327 {
 328     int ret;
 329
 330     ret = qemu_event_init();
 331     if (ret)
 332         return ret;
 333
 334     qemu_cond_init(&qemu_pause_cond);
 335     qemu_cond_init(&qemu_system_cond);
 336     qemu_mutex_init(&qemu_fair_mutex);
 337     qemu_mutex_init(&qemu_global_mutex);
 338     qemu_mutex_lock(&qemu_global_mutex);
 339
 340     unblock_io_signals();
 341     qemu_thread_self(&io_thread);
 342
 343     return 0;
 344 }
 345
 346 void qemu_main_loop_start(void)
 347 {
 348     qemu_system_ready = 1;
 349     qemu_cond_broadcast(&qemu_system_cond);
 350 }
 351
 352 void run_on_cpu(CPUState *env, void (*func)(void *data), void *data)
 353 {
 354     struct qemu_work_item wi;
 355
 356     if (qemu_cpu_self(env)) {
 357         func(data);
 358         return;
 359     }
 360
 361     wi.func = func;
 362     wi.data = data;
 363     if (!env->queued_work_first)
 364         env->queued_work_first = &wi;
 365     else
 366         env->queued_work_last->next = &wi;
 367     env->queued_work_last = &wi;
 368     wi.next = NULL;
 369     wi.done = false;
 370
 371     qemu_cpu_kick(env);
 372     while (!wi.done) {
 373         CPUState *self_env = cpu_single_env;
 374
 375         qemu_cond_wait(&qemu_work_cond, &qemu_global_mutex);
 376         cpu_single_env = self_env;
 377     }
 378 }
 379
 380 static void flush_queued_work(CPUState *env)
 381 {
 382     struct qemu_work_item *wi;
 383
 384     if (!env->queued_work_first)
 385         return;
 386
 387     while ((wi = env->queued_work_first)) {
 388         env->queued_work_first = wi->next;
 389         wi->func(wi->data);
 390         wi->done = true;
 391     }
 392     env->queued_work_last = NULL;
 393     qemu_cond_broadcast(&qemu_work_cond);
 394 }
 395
 396 static void qemu_wait_io_event_common(CPUState *env)
 397 {
 398     if (env->stop) {
 399         env->stop = 0;
 400         env->stopped = 1;
 401         qemu_cond_signal(&qemu_pause_cond);
 402     }
 403     flush_queued_work(env);
 404 }
 405
 406 static void qemu_wait_io_event(CPUState *env)
 407 {
 408     while (!tcg_has_work())
 409         qemu_cond_timedwait(env->halt_cond, &qemu_global_mutex, 1000);
 410
 411     qemu_mutex_unlock(&qemu_global_mutex);
 412
 413     /*
 414      * Users of qemu_global_mutex can be starved, having no chance
 415      * to acquire it since this path will get to it first.
 416      * So use another lock to provide fairness.
 417      */
 418     qemu_mutex_lock(&qemu_fair_mutex);
 419     qemu_mutex_unlock(&qemu_fair_mutex);
 420
 421     qemu_mutex_lock(&qemu_global_mutex);
 422     qemu_wait_io_event_common(env);
 423 }
 424
 425 static void qemu_kvm_eat_signal(CPUState *env, int timeout)
 426 {
 427     struct timespec ts;
 428     int r, e;
 429     siginfo_t siginfo;
 430     sigset_t waitset;
 431
 432     ts.tv_sec = timeout / 1000;
 433     ts.tv_nsec = (timeout % 1000) * 1000000;
 434
 435     sigemptyset(&waitset);
 436     sigaddset(&waitset, SIG_IPI);
 437
 438     qemu_mutex_unlock(&qemu_global_mutex);
 439     r = sigtimedwait(&waitset, &siginfo, &ts);
 440     e = errno;
 441     qemu_mutex_lock(&qemu_global_mutex);
 442
 443     if (r == -1 && !(e == EAGAIN || e == EINTR)) {
 444         fprintf(stderr, "sigtimedwait: %s\n", strerror(e));
 445         exit(1);
 446     }
 447 }
 448
 449 static void qemu_kvm_wait_io_event(CPUState *env)
 450 {
 451     while (!cpu_has_work(env))
 452         qemu_cond_timedwait(env->halt_cond, &qemu_global_mutex, 1000);
 453
 454     qemu_kvm_eat_signal(env, 0);
 455     qemu_wait_io_event_common(env);
 456 }
 457
 458 static int qemu_cpu_exec(CPUState *env);
 459
 460 static void *kvm_cpu_thread_fn(void *arg)
 461 {
 462     CPUState *env = arg;
 463
 464     qemu_mutex_lock(&qemu_global_mutex);
 465     qemu_thread_self(env->thread);
 466     if (kvm_enabled())
 467         kvm_init_vcpu(env);
 468
 469     kvm_init_ipi(env);
 470
 471     /* signal CPU creation */
 472     env->created = 1;
 473     qemu_cond_signal(&qemu_cpu_cond);
 474
 475     /* and wait for machine initialization */
 476     while (!qemu_system_ready)
 477         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 478
 479     while (1) {
 480         if (cpu_can_run(env))
 481             qemu_cpu_exec(env);
 482         qemu_kvm_wait_io_event(env);
 483     }
 484
 485     return NULL;
 486 }
 487
 488 static void *tcg_cpu_thread_fn(void *arg)
 489 {
 490     CPUState *env = arg;
 491
 492     tcg_init_ipi();
 493     qemu_thread_self(env->thread);
 494
 495     /* signal CPU creation */
 496     qemu_mutex_lock(&qemu_global_mutex);
 497     for (env = first_cpu; env != NULL; env = env->next_cpu)
 498         env->created = 1;
 499     qemu_cond_signal(&qemu_cpu_cond);
 500
 501     /* and wait for machine initialization */
 502     while (!qemu_system_ready)
 503         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 504
 505     while (1) {
 506         tcg_cpu_exec();
 507         qemu_wait_io_event(cur_cpu);
 508     }
 509
 510     return NULL;
 511 }
 512
 513 void qemu_cpu_kick(void *_env)
 514 {
 515     CPUState *env = _env;
 516     qemu_cond_broadcast(env->halt_cond);
 517     qemu_thread_signal(env->thread, SIG_IPI);
 518 }
 519
 520 int qemu_cpu_self(void *_env)
 521 {
 522     CPUState *env = _env;
 523     QemuThread this;
 524
 525     qemu_thread_self(&this);
 526
 527     return qemu_thread_equal(&this, env->thread);
 528 }
 529
 530 static void cpu_signal(int sig)
 531 {
 532     if (cpu_single_env)
 533         cpu_exit(cpu_single_env);
 534     exit_request = 1;
 535 }
 536
 537 static void tcg_init_ipi(void)
 538 {
 539     sigset_t set;
 540     struct sigaction sigact;
 541
 542     memset(&sigact, 0, sizeof(sigact));
 543     sigact.sa_handler = cpu_signal;
 544     sigaction(SIG_IPI, &sigact, NULL);
 545
 546     sigemptyset(&set);
 547     sigaddset(&set, SIG_IPI);
 548     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 549 }
 550
 551 static void dummy_signal(int sig)
 552 {
 553 }
 554
 555 static void kvm_init_ipi(CPUState *env)
 556 {
 557     int r;
 558     sigset_t set;
 559     struct sigaction sigact;
 560
 561     memset(&sigact, 0, sizeof(sigact));
 562     sigact.sa_handler = dummy_signal;
 563     sigaction(SIG_IPI, &sigact, NULL);
 564
 565     pthread_sigmask(SIG_BLOCK, NULL, &set);
 566     sigdelset(&set, SIG_IPI);
 567     r = kvm_set_signal_mask(env, &set);
 568     if (r) {
 569         fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(r));
 570         exit(1);
 571     }
 572 }
 573
 574 static void unblock_io_signals(void)
 575 {
 576     sigset_t set;
 577
 578     sigemptyset(&set);
 579     sigaddset(&set, SIGUSR2);
 580     sigaddset(&set, SIGIO);
 581     sigaddset(&set, SIGALRM);
 582     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 583
 584     sigemptyset(&set);
 585     sigaddset(&set, SIG_IPI);
 586     pthread_sigmask(SIG_BLOCK, &set, NULL);
 587 }
 588
 589 void qemu_mutex_lock_iothread(void)
 590 {
 591     if (kvm_enabled()) {
 592         qemu_mutex_lock(&qemu_fair_mutex);
 593         qemu_mutex_lock(&qemu_global_mutex);
 594         qemu_mutex_unlock(&qemu_fair_mutex);
 595     } else {
 596         qemu_mutex_lock(&qemu_fair_mutex);
 597         if (qemu_mutex_trylock(&qemu_global_mutex)) {
 598             qemu_thread_signal(tcg_cpu_thread, SIG_IPI);
 599             qemu_mutex_lock(&qemu_global_mutex);
 600         }
 601         qemu_mutex_unlock(&qemu_fair_mutex);
 602     }
 603 }
 604
 605 void qemu_mutex_unlock_iothread(void)
 606 {
 607     qemu_mutex_unlock(&qemu_global_mutex);
 608 }
 609
 610 static int all_vcpus_paused(void)
 611 {
 612     CPUState *penv = first_cpu;
 613
 614     while (penv) {
 615         if (!penv->stopped)
 616             return 0;
 617         penv = (CPUState *)penv->next_cpu;
 618     }
 619
 620     return 1;
 621 }
 622
 623 void pause_all_vcpus(void)
 624 {
 625     CPUState *penv = first_cpu;
 626
 627     while (penv) {
 628         penv->stop = 1;
 629         qemu_cpu_kick(penv);
 630         penv = (CPUState *)penv->next_cpu;
 631     }
 632
 633     while (!all_vcpus_paused()) {
 634         qemu_cond_timedwait(&qemu_pause_cond, &qemu_global_mutex, 100);
 635         penv = first_cpu;
 636         while (penv) {
 637             qemu_cpu_kick(penv);
 638             penv = (CPUState *)penv->next_cpu;
 639         }
 640     }
 641 }
 642
 643 void resume_all_vcpus(void)
 644 {
 645     CPUState *penv = first_cpu;
 646
 647     while (penv) {
 648         penv->stop = 0;
 649         penv->stopped = 0;
 650         qemu_cpu_kick(penv);
 651         penv = (CPUState *)penv->next_cpu;
 652     }
 653 }
 654
 655 static void tcg_init_vcpu(void *_env)
 656 {
 657     CPUState *env = _env;
 658     /* share a single thread for all cpus with TCG */
 659     if (!tcg_cpu_thread) {
 660         env->thread = qemu_mallocz(sizeof(QemuThread));
 661         env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 662         qemu_cond_init(env->halt_cond);
 663         qemu_thread_create(env->thread, tcg_cpu_thread_fn, env);
 664         while (env->created == 0)
 665             qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 666         tcg_cpu_thread = env->thread;
 667         tcg_halt_cond = env->halt_cond;
 668     } else {
 669         env->thread = tcg_cpu_thread;
 670         env->halt_cond = tcg_halt_cond;
 671     }
 672 }
 673
 674 static void kvm_start_vcpu(CPUState *env)
 675 {
 676     env->thread = qemu_mallocz(sizeof(QemuThread));
 677     env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 678     qemu_cond_init(env->halt_cond);
 679     qemu_thread_create(env->thread, kvm_cpu_thread_fn, env);
 680     while (env->created == 0)
 681         qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 682 }
 683
 684 void qemu_init_vcpu(void *_env)
 685 {
 686     CPUState *env = _env;
 687
 688     env->nr_cores = smp_cores;
 689     env->nr_threads = smp_threads;
 690     if (kvm_enabled())
 691         kvm_start_vcpu(env);
 692     else
 693         tcg_init_vcpu(env);
 694 }
 695
 696 void qemu_notify_event(void)
 697 {
 698     qemu_event_increment();
 699 }
 700
 701 static void qemu_system_vmstop_request(int reason)
 702 {
 703     vmstop_requested = reason;
 704     qemu_notify_event();
 705 }
 706
 707 void vm_stop(int reason)
 708 {
 709     QemuThread me;
 710     qemu_thread_self(&me);
 711
 712     if (!qemu_thread_equal(&me, &io_thread)) {
 713         qemu_system_vmstop_request(reason);
 714         /*
 715          * FIXME: should not return to device code in case
 716          * vm_stop() has been requested.
 717          */
 718         if (cpu_single_env) {
 719             cpu_exit(cpu_single_env);
 720             cpu_single_env->stop = 1;
 721         }
 722         return;
 723     }
 724     do_vm_stop(reason);
 725 }
 726
 727 #endif
 728
 729 static int qemu_cpu_exec(CPUState *env)
 730 {
 731     int ret;
 732 #ifdef CONFIG_PROFILER
 733     int64_t ti;
 734 #endif
 735
 736 #ifdef CONFIG_PROFILER
 737     ti = profile_getclock();
 738 #endif
 739     if (use_icount) {
 740         int64_t count;
 741         int decr;
 742         qemu_icount -= (env->icount_decr.u16.low + env->icount_extra);
 743         env->icount_decr.u16.low = 0;
 744         env->icount_extra = 0;
 745         count = qemu_icount_round (qemu_next_deadline());
 746         qemu_icount += count;
 747         decr = (count > 0xffff) ? 0xffff : count;
 748         count -= decr;
 749         env->icount_decr.u16.low = decr;
 750         env->icount_extra = count;
 751     }
 752     ret = cpu_exec(env);
 753 #ifdef CONFIG_PROFILER
 754     qemu_time += profile_getclock() - ti;
 755 #endif
 756     if (use_icount) {
 757         /* Fold pending instructions back into the
 758            instruction counter, and clear the interrupt flag.  */
 759         qemu_icount -= (env->icount_decr.u16.low
 760                         + env->icount_extra);
 761         env->icount_decr.u32 = 0;
 762         env->icount_extra = 0;
 763     }
 764     return ret;
 765 }
 766
 767 bool tcg_cpu_exec(void)
 768 {
 769     int ret = 0;
 770
 771     if (next_cpu == NULL)
 772         next_cpu = first_cpu;
 773     for (; next_cpu != NULL && !exit_request; next_cpu = next_cpu->next_cpu) {
 774         CPUState *env = cur_cpu = next_cpu;
 775
 776         qemu_clock_enable(vm_clock,
 777                           (cur_cpu->singlestep_enabled & SSTEP_NOTIMER) == 0);
 778
 779         if (qemu_alarm_pending())
 780             break;
 781         if (cpu_can_run(env))
 782             ret = qemu_cpu_exec(env);
 783         else if (env->stop)
 784             break;
 785
 786         if (ret == EXCP_DEBUG) {
 787             gdb_set_stop_cpu(env);
 788             debug_requested = EXCP_DEBUG;
 789             break;
 790         }
 791     }
 792     exit_request = 0;
 793     return tcg_has_work();
 794 }
 795
 796 void set_numa_modes(void)
 797 {
 798     CPUState *env;
 799     int i;
 800
 801     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 802         for (i = 0; i < nb_numa_nodes; i++) {
 803             if (node_cpumask[i] & (1 << env->cpu_index)) {
 804                 env->numa_node = i;
 805             }
 806         }
 807     }
 808 }
 809
 810 void set_cpu_log(const char *optarg)
 811 {
 812     int mask;
 813     const CPULogItem *item;
 814
 815     mask = cpu_str_to_log_mask(optarg);
 816     if (!mask) {
 817         printf("Log items (comma separated):\n");
 818         for (item = cpu_log_items; item->mask != 0; item++) {
 819             printf("%-10s %s\n", item->name, item->help);
 820         }
 821         exit(1);
 822     }
 823     cpu_set_log(mask);
 824 }
 825
 826 /* Return the virtual CPU time, based on the instruction counter.  */
 827 int64_t cpu_get_icount(void)
 828 {
 829     int64_t icount;
 830     CPUState *env = cpu_single_env;;
 831
 832     icount = qemu_icount;
 833     if (env) {
 834         if (!can_do_io(env)) {
 835             fprintf(stderr, "Bad clock read\n");
 836         }
 837         icount -= (env->icount_decr.u16.low + env->icount_extra);
 838     }
 839     return qemu_icount_bias + (icount << icount_time_shift);
 840 }
 841
 842 void list_cpus(FILE *f, int (*cpu_fprintf)(FILE *f, const char *fmt, ...),
 843                const char *optarg)
 844 {
 845     /* XXX: implement xxx_cpu_list for targets that still miss it */
 846 #if defined(cpu_list_id)
 847     cpu_list_id(f, cpu_fprintf, optarg);
 848 #elif defined(cpu_list)
 849     cpu_list(f, cpu_fprintf); /* deprecated */
 850 #endif
 851 }