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 *next_cpu;
  44
  45 /***********************************************************/
  46 void hw_error(const char *fmt, ...)
  47 {
  48     va_list ap;
  49     CPUState *env;
  50
  51     va_start(ap, fmt);
  52     fprintf(stderr, "qemu: hardware error: ");
  53     vfprintf(stderr, fmt, ap);
  54     fprintf(stderr, "\n");
  55     for(env = first_cpu; env != NULL; env = env->next_cpu) {
  56         fprintf(stderr, "CPU #%d:\n", env->cpu_index);
  57 #ifdef TARGET_I386
  58         cpu_dump_state(env, stderr, fprintf, X86_DUMP_FPU);
  59 #else
  60         cpu_dump_state(env, stderr, fprintf, 0);
  61 #endif
  62     }
  63     va_end(ap);
  64     abort();
  65 }
  66
  67 void cpu_synchronize_all_states(void)
  68 {
  69     CPUState *cpu;
  70
  71     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  72         cpu_synchronize_state(cpu);
  73     }
  74 }
  75
  76 void cpu_synchronize_all_post_reset(void)
  77 {
  78     CPUState *cpu;
  79
  80     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  81         cpu_synchronize_post_reset(cpu);
  82     }
  83 }
  84
  85 void cpu_synchronize_all_post_init(void)
  86 {
  87     CPUState *cpu;
  88
  89     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  90         cpu_synchronize_post_init(cpu);
  91     }
  92 }
  93
  94 int cpu_is_stopped(CPUState *env)
  95 {
  96     return !vm_running || env->stopped;
  97 }
  98
  99 static void do_vm_stop(int reason)
 100 {
 101     if (vm_running) {
 102         cpu_disable_ticks();
 103         vm_running = 0;
 104         pause_all_vcpus();
 105         vm_state_notify(0, reason);
 106         monitor_protocol_event(QEVENT_STOP, NULL);
 107     }
 108 }
 109
 110 static int cpu_can_run(CPUState *env)
 111 {
 112     if (env->stop)
 113         return 0;
 114     if (env->stopped || !vm_running)
 115         return 0;
 116     return 1;
 117 }
 118
 119 static int cpu_has_work(CPUState *env)
 120 {
 121     if (env->stop)
 122         return 1;
 123     if (env->queued_work_first)
 124         return 1;
 125     if (env->stopped || !vm_running)
 126         return 0;
 127     if (!env->halted)
 128         return 1;
 129     if (qemu_cpu_has_work(env))
 130         return 1;
 131     return 0;
 132 }
 133
 134 static int tcg_has_work(void)
 135 {
 136     CPUState *env;
 137
 138     for (env = first_cpu; env != NULL; env = env->next_cpu)
 139         if (cpu_has_work(env))
 140             return 1;
 141     return 0;
 142 }
 143
 144 #ifndef _WIN32
 145 static int io_thread_fd = -1;
 146
 147 static void qemu_event_increment(void)
 148 {
 149     /* Write 8 bytes to be compatible with eventfd.  */
 150     static const uint64_t val = 1;
 151     ssize_t ret;
 152
 153     if (io_thread_fd == -1)
 154         return;
 155
 156     do {
 157         ret = write(io_thread_fd, &val, sizeof(val));
 158     } while (ret < 0 && errno == EINTR);
 159
 160     /* EAGAIN is fine, a read must be pending.  */
 161     if (ret < 0 && errno != EAGAIN) {
 162         fprintf(stderr, "qemu_event_increment: write() filed: %s\n",
 163                 strerror(errno));
 164         exit (1);
 165     }
 166 }
 167
 168 static void qemu_event_read(void *opaque)
 169 {
 170     int fd = (unsigned long)opaque;
 171     ssize_t len;
 172     char buffer[512];
 173
 174     /* Drain the notify pipe.  For eventfd, only 8 bytes will be read.  */
 175     do {
 176         len = read(fd, buffer, sizeof(buffer));
 177     } while ((len == -1 && errno == EINTR) || len == sizeof(buffer));
 178 }
 179
 180 static int qemu_event_init(void)
 181 {
 182     int err;
 183     int fds[2];
 184
 185     err = qemu_eventfd(fds);
 186     if (err == -1)
 187         return -errno;
 188
 189     err = fcntl_setfl(fds[0], O_NONBLOCK);
 190     if (err < 0)
 191         goto fail;
 192
 193     err = fcntl_setfl(fds[1], O_NONBLOCK);
 194     if (err < 0)
 195         goto fail;
 196
 197     qemu_set_fd_handler2(fds[0], NULL, qemu_event_read, NULL,
 198                          (void *)(unsigned long)fds[0]);
 199
 200     io_thread_fd = fds[1];
 201     return 0;
 202
 203 fail:
 204     close(fds[0]);
 205     close(fds[1]);
 206     return err;
 207 }
 208 #else
 209 HANDLE qemu_event_handle;
 210
 211 static void dummy_event_handler(void *opaque)
 212 {
 213 }
 214
 215 static int qemu_event_init(void)
 216 {
 217     qemu_event_handle = CreateEvent(NULL, FALSE, FALSE, NULL);
 218     if (!qemu_event_handle) {
 219         fprintf(stderr, "Failed CreateEvent: %ld\n", GetLastError());
 220         return -1;
 221     }
 222     qemu_add_wait_object(qemu_event_handle, dummy_event_handler, NULL);
 223     return 0;
 224 }
 225
 226 static void qemu_event_increment(void)
 227 {
 228     if (!SetEvent(qemu_event_handle)) {
 229         fprintf(stderr, "qemu_event_increment: SetEvent failed: %ld\n",
 230                 GetLastError());
 231         exit (1);
 232     }
 233 }
 234 #endif
 235
 236 #ifndef CONFIG_IOTHREAD
 237 int qemu_init_main_loop(void)
 238 {
 239     return qemu_event_init();
 240 }
 241
 242 void qemu_main_loop_start(void)
 243 {
 244 }
 245
 246 void qemu_init_vcpu(void *_env)
 247 {
 248     CPUState *env = _env;
 249
 250     env->nr_cores = smp_cores;
 251     env->nr_threads = smp_threads;
 252     if (kvm_enabled())
 253         kvm_init_vcpu(env);
 254     return;
 255 }
 256
 257 int qemu_cpu_self(void *env)
 258 {
 259     return 1;
 260 }
 261
 262 void run_on_cpu(CPUState *env, void (*func)(void *data), void *data)
 263 {
 264     func(data);
 265 }
 266
 267 void resume_all_vcpus(void)
 268 {
 269 }
 270
 271 void pause_all_vcpus(void)
 272 {
 273 }
 274
 275 void qemu_cpu_kick(void *env)
 276 {
 277     return;
 278 }
 279
 280 void qemu_notify_event(void)
 281 {
 282     CPUState *env = cpu_single_env;
 283
 284     qemu_event_increment ();
 285     if (env) {
 286         cpu_exit(env);
 287     }
 288     if (next_cpu && env != next_cpu) {
 289         cpu_exit(next_cpu);
 290     }
 291 }
 292
 293 void qemu_mutex_lock_iothread(void) {}
 294 void qemu_mutex_unlock_iothread(void) {}
 295
 296 void vm_stop(int reason)
 297 {
 298     do_vm_stop(reason);
 299 }
 300
 301 #else /* CONFIG_IOTHREAD */
 302
 303 #include "qemu-thread.h"
 304
 305 QemuMutex qemu_global_mutex;
 306 static QemuMutex qemu_fair_mutex;
 307
 308 static QemuThread io_thread;
 309
 310 static QemuThread *tcg_cpu_thread;
 311 static QemuCond *tcg_halt_cond;
 312
 313 static int qemu_system_ready;
 314 /* cpu creation */
 315 static QemuCond qemu_cpu_cond;
 316 /* system init */
 317 static QemuCond qemu_system_cond;
 318 static QemuCond qemu_pause_cond;
 319 static QemuCond qemu_work_cond;
 320
 321 static void tcg_init_ipi(void);
 322 static void kvm_init_ipi(CPUState *env);
 323 static void unblock_io_signals(void);
 324
 325 int qemu_init_main_loop(void)
 326 {
 327     int ret;
 328
 329     ret = qemu_event_init();
 330     if (ret)
 331         return ret;
 332
 333     qemu_cond_init(&qemu_pause_cond);
 334     qemu_cond_init(&qemu_system_cond);
 335     qemu_mutex_init(&qemu_fair_mutex);
 336     qemu_mutex_init(&qemu_global_mutex);
 337     qemu_mutex_lock(&qemu_global_mutex);
 338
 339     unblock_io_signals();
 340     qemu_thread_self(&io_thread);
 341
 342     return 0;
 343 }
 344
 345 void qemu_main_loop_start(void)
 346 {
 347     qemu_system_ready = 1;
 348     qemu_cond_broadcast(&qemu_system_cond);
 349 }
 350
 351 void run_on_cpu(CPUState *env, void (*func)(void *data), void *data)
 352 {
 353     struct qemu_work_item wi;
 354
 355     if (qemu_cpu_self(env)) {
 356         func(data);
 357         return;
 358     }
 359
 360     wi.func = func;
 361     wi.data = data;
 362     if (!env->queued_work_first)
 363         env->queued_work_first = &wi;
 364     else
 365         env->queued_work_last->next = &wi;
 366     env->queued_work_last = &wi;
 367     wi.next = NULL;
 368     wi.done = false;
 369
 370     qemu_cpu_kick(env);
 371     while (!wi.done) {
 372         CPUState *self_env = cpu_single_env;
 373
 374         qemu_cond_wait(&qemu_work_cond, &qemu_global_mutex);
 375         cpu_single_env = self_env;
 376     }
 377 }
 378
 379 static void flush_queued_work(CPUState *env)
 380 {
 381     struct qemu_work_item *wi;
 382
 383     if (!env->queued_work_first)
 384         return;
 385
 386     while ((wi = env->queued_work_first)) {
 387         env->queued_work_first = wi->next;
 388         wi->func(wi->data);
 389         wi->done = true;
 390     }
 391     env->queued_work_last = NULL;
 392     qemu_cond_broadcast(&qemu_work_cond);
 393 }
 394
 395 static void qemu_wait_io_event_common(CPUState *env)
 396 {
 397     if (env->stop) {
 398         env->stop = 0;
 399         env->stopped = 1;
 400         qemu_cond_signal(&qemu_pause_cond);
 401     }
 402     flush_queued_work(env);
 403 }
 404
 405 static void qemu_tcg_wait_io_event(void)
 406 {
 407     CPUState *env;
 408
 409     while (!tcg_has_work())
 410         qemu_cond_timedwait(tcg_halt_cond, &qemu_global_mutex, 1000);
 411
 412     qemu_mutex_unlock(&qemu_global_mutex);
 413
 414     /*
 415      * Users of qemu_global_mutex can be starved, having no chance
 416      * to acquire it since this path will get to it first.
 417      * So use another lock to provide fairness.
 418      */
 419     qemu_mutex_lock(&qemu_fair_mutex);
 420     qemu_mutex_unlock(&qemu_fair_mutex);
 421
 422     qemu_mutex_lock(&qemu_global_mutex);
 423
 424     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 425         qemu_wait_io_event_common(env);
 426     }
 427 }
 428
 429 static void qemu_kvm_eat_signal(CPUState *env, int timeout)
 430 {
 431     struct timespec ts;
 432     int r, e;
 433     siginfo_t siginfo;
 434     sigset_t waitset;
 435
 436     ts.tv_sec = timeout / 1000;
 437     ts.tv_nsec = (timeout % 1000) * 1000000;
 438
 439     sigemptyset(&waitset);
 440     sigaddset(&waitset, SIG_IPI);
 441
 442     qemu_mutex_unlock(&qemu_global_mutex);
 443     r = sigtimedwait(&waitset, &siginfo, &ts);
 444     e = errno;
 445     qemu_mutex_lock(&qemu_global_mutex);
 446
 447     if (r == -1 && !(e == EAGAIN || e == EINTR)) {
 448         fprintf(stderr, "sigtimedwait: %s\n", strerror(e));
 449         exit(1);
 450     }
 451 }
 452
 453 static void qemu_kvm_wait_io_event(CPUState *env)
 454 {
 455     while (!cpu_has_work(env))
 456         qemu_cond_timedwait(env->halt_cond, &qemu_global_mutex, 1000);
 457
 458     qemu_kvm_eat_signal(env, 0);
 459     qemu_wait_io_event_common(env);
 460 }
 461
 462 static int qemu_cpu_exec(CPUState *env);
 463
 464 static void *kvm_cpu_thread_fn(void *arg)
 465 {
 466     CPUState *env = arg;
 467
 468     qemu_mutex_lock(&qemu_global_mutex);
 469     qemu_thread_self(env->thread);
 470     if (kvm_enabled())
 471         kvm_init_vcpu(env);
 472
 473     kvm_init_ipi(env);
 474
 475     /* signal CPU creation */
 476     env->created = 1;
 477     qemu_cond_signal(&qemu_cpu_cond);
 478
 479     /* and wait for machine initialization */
 480     while (!qemu_system_ready)
 481         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 482
 483     while (1) {
 484         if (cpu_can_run(env))
 485             qemu_cpu_exec(env);
 486         qemu_kvm_wait_io_event(env);
 487     }
 488
 489     return NULL;
 490 }
 491
 492 static void *tcg_cpu_thread_fn(void *arg)
 493 {
 494     CPUState *env = arg;
 495
 496     tcg_init_ipi();
 497     qemu_thread_self(env->thread);
 498
 499     /* signal CPU creation */
 500     qemu_mutex_lock(&qemu_global_mutex);
 501     for (env = first_cpu; env != NULL; env = env->next_cpu)
 502         env->created = 1;
 503     qemu_cond_signal(&qemu_cpu_cond);
 504
 505     /* and wait for machine initialization */
 506     while (!qemu_system_ready)
 507         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 508
 509     while (1) {
 510         tcg_cpu_exec();
 511         qemu_tcg_wait_io_event();
 512     }
 513
 514     return NULL;
 515 }
 516
 517 void qemu_cpu_kick(void *_env)
 518 {
 519     CPUState *env = _env;
 520     qemu_cond_broadcast(env->halt_cond);
 521     qemu_thread_signal(env->thread, SIG_IPI);
 522 }
 523
 524 int qemu_cpu_self(void *_env)
 525 {
 526     CPUState *env = _env;
 527     QemuThread this;
 528
 529     qemu_thread_self(&this);
 530
 531     return qemu_thread_equal(&this, env->thread);
 532 }
 533
 534 static void cpu_signal(int sig)
 535 {
 536     if (cpu_single_env)
 537         cpu_exit(cpu_single_env);
 538     exit_request = 1;
 539 }
 540
 541 static void tcg_init_ipi(void)
 542 {
 543     sigset_t set;
 544     struct sigaction sigact;
 545
 546     memset(&sigact, 0, sizeof(sigact));
 547     sigact.sa_handler = cpu_signal;
 548     sigaction(SIG_IPI, &sigact, NULL);
 549
 550     sigemptyset(&set);
 551     sigaddset(&set, SIG_IPI);
 552     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 553 }
 554
 555 static void dummy_signal(int sig)
 556 {
 557 }
 558
 559 static void kvm_init_ipi(CPUState *env)
 560 {
 561     int r;
 562     sigset_t set;
 563     struct sigaction sigact;
 564
 565     memset(&sigact, 0, sizeof(sigact));
 566     sigact.sa_handler = dummy_signal;
 567     sigaction(SIG_IPI, &sigact, NULL);
 568
 569     pthread_sigmask(SIG_BLOCK, NULL, &set);
 570     sigdelset(&set, SIG_IPI);
 571     r = kvm_set_signal_mask(env, &set);
 572     if (r) {
 573         fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(r));
 574         exit(1);
 575     }
 576 }
 577
 578 static void unblock_io_signals(void)
 579 {
 580     sigset_t set;
 581
 582     sigemptyset(&set);
 583     sigaddset(&set, SIGUSR2);
 584     sigaddset(&set, SIGIO);
 585     sigaddset(&set, SIGALRM);
 586     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 587
 588     sigemptyset(&set);
 589     sigaddset(&set, SIG_IPI);
 590     pthread_sigmask(SIG_BLOCK, &set, NULL);
 591 }
 592
 593 void qemu_mutex_lock_iothread(void)
 594 {
 595     if (kvm_enabled()) {
 596         qemu_mutex_lock(&qemu_fair_mutex);
 597         qemu_mutex_lock(&qemu_global_mutex);
 598         qemu_mutex_unlock(&qemu_fair_mutex);
 599     } else {
 600         qemu_mutex_lock(&qemu_fair_mutex);
 601         if (qemu_mutex_trylock(&qemu_global_mutex)) {
 602             qemu_thread_signal(tcg_cpu_thread, SIG_IPI);
 603             qemu_mutex_lock(&qemu_global_mutex);
 604         }
 605         qemu_mutex_unlock(&qemu_fair_mutex);
 606     }
 607 }
 608
 609 void qemu_mutex_unlock_iothread(void)
 610 {
 611     qemu_mutex_unlock(&qemu_global_mutex);
 612 }
 613
 614 static int all_vcpus_paused(void)
 615 {
 616     CPUState *penv = first_cpu;
 617
 618     while (penv) {
 619         if (!penv->stopped)
 620             return 0;
 621         penv = (CPUState *)penv->next_cpu;
 622     }
 623
 624     return 1;
 625 }
 626
 627 void pause_all_vcpus(void)
 628 {
 629     CPUState *penv = first_cpu;
 630
 631     while (penv) {
 632         penv->stop = 1;
 633         qemu_cpu_kick(penv);
 634         penv = (CPUState *)penv->next_cpu;
 635     }
 636
 637     while (!all_vcpus_paused()) {
 638         qemu_cond_timedwait(&qemu_pause_cond, &qemu_global_mutex, 100);
 639         penv = first_cpu;
 640         while (penv) {
 641             qemu_cpu_kick(penv);
 642             penv = (CPUState *)penv->next_cpu;
 643         }
 644     }
 645 }
 646
 647 void resume_all_vcpus(void)
 648 {
 649     CPUState *penv = first_cpu;
 650
 651     while (penv) {
 652         penv->stop = 0;
 653         penv->stopped = 0;
 654         qemu_cpu_kick(penv);
 655         penv = (CPUState *)penv->next_cpu;
 656     }
 657 }
 658
 659 static void tcg_init_vcpu(void *_env)
 660 {
 661     CPUState *env = _env;
 662     /* share a single thread for all cpus with TCG */
 663     if (!tcg_cpu_thread) {
 664         env->thread = qemu_mallocz(sizeof(QemuThread));
 665         env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 666         qemu_cond_init(env->halt_cond);
 667         qemu_thread_create(env->thread, tcg_cpu_thread_fn, env);
 668         while (env->created == 0)
 669             qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 670         tcg_cpu_thread = env->thread;
 671         tcg_halt_cond = env->halt_cond;
 672     } else {
 673         env->thread = tcg_cpu_thread;
 674         env->halt_cond = tcg_halt_cond;
 675     }
 676 }
 677
 678 static void kvm_start_vcpu(CPUState *env)
 679 {
 680     env->thread = qemu_mallocz(sizeof(QemuThread));
 681     env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 682     qemu_cond_init(env->halt_cond);
 683     qemu_thread_create(env->thread, kvm_cpu_thread_fn, env);
 684     while (env->created == 0)
 685         qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 686 }
 687
 688 void qemu_init_vcpu(void *_env)
 689 {
 690     CPUState *env = _env;
 691
 692     env->nr_cores = smp_cores;
 693     env->nr_threads = smp_threads;
 694     if (kvm_enabled())
 695         kvm_start_vcpu(env);
 696     else
 697         tcg_init_vcpu(env);
 698 }
 699
 700 void qemu_notify_event(void)
 701 {
 702     qemu_event_increment();
 703 }
 704
 705 static void qemu_system_vmstop_request(int reason)
 706 {
 707     vmstop_requested = reason;
 708     qemu_notify_event();
 709 }
 710
 711 void vm_stop(int reason)
 712 {
 713     QemuThread me;
 714     qemu_thread_self(&me);
 715
 716     if (!qemu_thread_equal(&me, &io_thread)) {
 717         qemu_system_vmstop_request(reason);
 718         /*
 719          * FIXME: should not return to device code in case
 720          * vm_stop() has been requested.
 721          */
 722         if (cpu_single_env) {
 723             cpu_exit(cpu_single_env);
 724             cpu_single_env->stop = 1;
 725         }
 726         return;
 727     }
 728     do_vm_stop(reason);
 729 }
 730
 731 #endif
 732
 733 static int qemu_cpu_exec(CPUState *env)
 734 {
 735     int ret;
 736 #ifdef CONFIG_PROFILER
 737     int64_t ti;
 738 #endif
 739
 740 #ifdef CONFIG_PROFILER
 741     ti = profile_getclock();
 742 #endif
 743     if (use_icount) {
 744         int64_t count;
 745         int decr;
 746         qemu_icount -= (env->icount_decr.u16.low + env->icount_extra);
 747         env->icount_decr.u16.low = 0;
 748         env->icount_extra = 0;
 749         count = qemu_icount_round (qemu_next_deadline());
 750         qemu_icount += count;
 751         decr = (count > 0xffff) ? 0xffff : count;
 752         count -= decr;
 753         env->icount_decr.u16.low = decr;
 754         env->icount_extra = count;
 755     }
 756     ret = cpu_exec(env);
 757 #ifdef CONFIG_PROFILER
 758     qemu_time += profile_getclock() - ti;
 759 #endif
 760     if (use_icount) {
 761         /* Fold pending instructions back into the
 762            instruction counter, and clear the interrupt flag.  */
 763         qemu_icount -= (env->icount_decr.u16.low
 764                         + env->icount_extra);
 765         env->icount_decr.u32 = 0;
 766         env->icount_extra = 0;
 767     }
 768     return ret;
 769 }
 770
 771 bool tcg_cpu_exec(void)
 772 {
 773     int ret = 0;
 774
 775     if (next_cpu == NULL)
 776         next_cpu = first_cpu;
 777     for (; next_cpu != NULL && !exit_request; next_cpu = next_cpu->next_cpu) {
 778         CPUState *env = next_cpu;
 779
 780         qemu_clock_enable(vm_clock,
 781                           (env->singlestep_enabled & SSTEP_NOTIMER) == 0);
 782
 783         if (qemu_alarm_pending())
 784             break;
 785         if (cpu_can_run(env))
 786             ret = qemu_cpu_exec(env);
 787         else if (env->stop)
 788             break;
 789
 790         if (ret == EXCP_DEBUG) {
 791             gdb_set_stop_cpu(env);
 792             debug_requested = EXCP_DEBUG;
 793             break;
 794         }
 795     }
 796     exit_request = 0;
 797     return tcg_has_work();
 798 }
 799
 800 void set_numa_modes(void)
 801 {
 802     CPUState *env;
 803     int i;
 804
 805     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 806         for (i = 0; i < nb_numa_nodes; i++) {
 807             if (node_cpumask[i] & (1 << env->cpu_index)) {
 808                 env->numa_node = i;
 809             }
 810         }
 811     }
 812 }
 813
 814 void set_cpu_log(const char *optarg)
 815 {
 816     int mask;
 817     const CPULogItem *item;
 818
 819     mask = cpu_str_to_log_mask(optarg);
 820     if (!mask) {
 821         printf("Log items (comma separated):\n");
 822         for (item = cpu_log_items; item->mask != 0; item++) {
 823             printf("%-10s %s\n", item->name, item->help);
 824         }
 825         exit(1);
 826     }
 827     cpu_set_log(mask);
 828 }
 829
 830 /* Return the virtual CPU time, based on the instruction counter.  */
 831 int64_t cpu_get_icount(void)
 832 {
 833     int64_t icount;
 834     CPUState *env = cpu_single_env;;
 835
 836     icount = qemu_icount;
 837     if (env) {
 838         if (!can_do_io(env)) {
 839             fprintf(stderr, "Bad clock read\n");
 840         }
 841         icount -= (env->icount_decr.u16.low + env->icount_extra);
 842     }
 843     return qemu_icount_bias + (icount << icount_time_shift);
 844 }
 845
 846 void list_cpus(FILE *f, int (*cpu_fprintf)(FILE *f, const char *fmt, ...),
 847                const char *optarg)
 848 {
 849     /* XXX: implement xxx_cpu_list for targets that still miss it */
 850 #if defined(cpu_list_id)
 851     cpu_list_id(f, cpu_fprintf, optarg);
 852 #elif defined(cpu_list)
 853     cpu_list(f, cpu_fprintf); /* deprecated */
 854 #endif
 855 }