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_tcg_wait_io_event(void)
 407 {
 408     CPUState *env;
 409
 410     while (!tcg_has_work())
 411         qemu_cond_timedwait(tcg_halt_cond, &qemu_global_mutex, 1000);
 412
 413     qemu_mutex_unlock(&qemu_global_mutex);
 414
 415     /*
 416      * Users of qemu_global_mutex can be starved, having no chance
 417      * to acquire it since this path will get to it first.
 418      * So use another lock to provide fairness.
 419      */
 420     qemu_mutex_lock(&qemu_fair_mutex);
 421     qemu_mutex_unlock(&qemu_fair_mutex);
 422
 423     qemu_mutex_lock(&qemu_global_mutex);
 424
 425     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 426         qemu_wait_io_event_common(env);
 427     }
 428 }
 429
 430 static void qemu_kvm_eat_signal(CPUState *env, int timeout)
 431 {
 432     struct timespec ts;
 433     int r, e;
 434     siginfo_t siginfo;
 435     sigset_t waitset;
 436
 437     ts.tv_sec = timeout / 1000;
 438     ts.tv_nsec = (timeout % 1000) * 1000000;
 439
 440     sigemptyset(&waitset);
 441     sigaddset(&waitset, SIG_IPI);
 442
 443     qemu_mutex_unlock(&qemu_global_mutex);
 444     r = sigtimedwait(&waitset, &siginfo, &ts);
 445     e = errno;
 446     qemu_mutex_lock(&qemu_global_mutex);
 447
 448     if (r == -1 && !(e == EAGAIN || e == EINTR)) {
 449         fprintf(stderr, "sigtimedwait: %s\n", strerror(e));
 450         exit(1);
 451     }
 452 }
 453
 454 static void qemu_kvm_wait_io_event(CPUState *env)
 455 {
 456     while (!cpu_has_work(env))
 457         qemu_cond_timedwait(env->halt_cond, &qemu_global_mutex, 1000);
 458
 459     qemu_kvm_eat_signal(env, 0);
 460     qemu_wait_io_event_common(env);
 461 }
 462
 463 static int qemu_cpu_exec(CPUState *env);
 464
 465 static void *kvm_cpu_thread_fn(void *arg)
 466 {
 467     CPUState *env = arg;
 468
 469     qemu_mutex_lock(&qemu_global_mutex);
 470     qemu_thread_self(env->thread);
 471     if (kvm_enabled())
 472         kvm_init_vcpu(env);
 473
 474     kvm_init_ipi(env);
 475
 476     /* signal CPU creation */
 477     env->created = 1;
 478     qemu_cond_signal(&qemu_cpu_cond);
 479
 480     /* and wait for machine initialization */
 481     while (!qemu_system_ready)
 482         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 483
 484     while (1) {
 485         if (cpu_can_run(env))
 486             qemu_cpu_exec(env);
 487         qemu_kvm_wait_io_event(env);
 488     }
 489
 490     return NULL;
 491 }
 492
 493 static void *tcg_cpu_thread_fn(void *arg)
 494 {
 495     CPUState *env = arg;
 496
 497     tcg_init_ipi();
 498     qemu_thread_self(env->thread);
 499
 500     /* signal CPU creation */
 501     qemu_mutex_lock(&qemu_global_mutex);
 502     for (env = first_cpu; env != NULL; env = env->next_cpu)
 503         env->created = 1;
 504     qemu_cond_signal(&qemu_cpu_cond);
 505
 506     /* and wait for machine initialization */
 507     while (!qemu_system_ready)
 508         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 509
 510     while (1) {
 511         tcg_cpu_exec();
 512         qemu_tcg_wait_io_event();
 513     }
 514
 515     return NULL;
 516 }
 517
 518 void qemu_cpu_kick(void *_env)
 519 {
 520     CPUState *env = _env;
 521     qemu_cond_broadcast(env->halt_cond);
 522     qemu_thread_signal(env->thread, SIG_IPI);
 523 }
 524
 525 int qemu_cpu_self(void *_env)
 526 {
 527     CPUState *env = _env;
 528     QemuThread this;
 529
 530     qemu_thread_self(&this);
 531
 532     return qemu_thread_equal(&this, env->thread);
 533 }
 534
 535 static void cpu_signal(int sig)
 536 {
 537     if (cpu_single_env)
 538         cpu_exit(cpu_single_env);
 539     exit_request = 1;
 540 }
 541
 542 static void tcg_init_ipi(void)
 543 {
 544     sigset_t set;
 545     struct sigaction sigact;
 546
 547     memset(&sigact, 0, sizeof(sigact));
 548     sigact.sa_handler = cpu_signal;
 549     sigaction(SIG_IPI, &sigact, NULL);
 550
 551     sigemptyset(&set);
 552     sigaddset(&set, SIG_IPI);
 553     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 554 }
 555
 556 static void dummy_signal(int sig)
 557 {
 558 }
 559
 560 static void kvm_init_ipi(CPUState *env)
 561 {
 562     int r;
 563     sigset_t set;
 564     struct sigaction sigact;
 565
 566     memset(&sigact, 0, sizeof(sigact));
 567     sigact.sa_handler = dummy_signal;
 568     sigaction(SIG_IPI, &sigact, NULL);
 569
 570     pthread_sigmask(SIG_BLOCK, NULL, &set);
 571     sigdelset(&set, SIG_IPI);
 572     r = kvm_set_signal_mask(env, &set);
 573     if (r) {
 574         fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(r));
 575         exit(1);
 576     }
 577 }
 578
 579 static void unblock_io_signals(void)
 580 {
 581     sigset_t set;
 582
 583     sigemptyset(&set);
 584     sigaddset(&set, SIGUSR2);
 585     sigaddset(&set, SIGIO);
 586     sigaddset(&set, SIGALRM);
 587     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 588
 589     sigemptyset(&set);
 590     sigaddset(&set, SIG_IPI);
 591     pthread_sigmask(SIG_BLOCK, &set, NULL);
 592 }
 593
 594 void qemu_mutex_lock_iothread(void)
 595 {
 596     if (kvm_enabled()) {
 597         qemu_mutex_lock(&qemu_fair_mutex);
 598         qemu_mutex_lock(&qemu_global_mutex);
 599         qemu_mutex_unlock(&qemu_fair_mutex);
 600     } else {
 601         qemu_mutex_lock(&qemu_fair_mutex);
 602         if (qemu_mutex_trylock(&qemu_global_mutex)) {
 603             qemu_thread_signal(tcg_cpu_thread, SIG_IPI);
 604             qemu_mutex_lock(&qemu_global_mutex);
 605         }
 606         qemu_mutex_unlock(&qemu_fair_mutex);
 607     }
 608 }
 609
 610 void qemu_mutex_unlock_iothread(void)
 611 {
 612     qemu_mutex_unlock(&qemu_global_mutex);
 613 }
 614
 615 static int all_vcpus_paused(void)
 616 {
 617     CPUState *penv = first_cpu;
 618
 619     while (penv) {
 620         if (!penv->stopped)
 621             return 0;
 622         penv = (CPUState *)penv->next_cpu;
 623     }
 624
 625     return 1;
 626 }
 627
 628 void pause_all_vcpus(void)
 629 {
 630     CPUState *penv = first_cpu;
 631
 632     while (penv) {
 633         penv->stop = 1;
 634         qemu_cpu_kick(penv);
 635         penv = (CPUState *)penv->next_cpu;
 636     }
 637
 638     while (!all_vcpus_paused()) {
 639         qemu_cond_timedwait(&qemu_pause_cond, &qemu_global_mutex, 100);
 640         penv = first_cpu;
 641         while (penv) {
 642             qemu_cpu_kick(penv);
 643             penv = (CPUState *)penv->next_cpu;
 644         }
 645     }
 646 }
 647
 648 void resume_all_vcpus(void)
 649 {
 650     CPUState *penv = first_cpu;
 651
 652     while (penv) {
 653         penv->stop = 0;
 654         penv->stopped = 0;
 655         qemu_cpu_kick(penv);
 656         penv = (CPUState *)penv->next_cpu;
 657     }
 658 }
 659
 660 static void tcg_init_vcpu(void *_env)
 661 {
 662     CPUState *env = _env;
 663     /* share a single thread for all cpus with TCG */
 664     if (!tcg_cpu_thread) {
 665         env->thread = qemu_mallocz(sizeof(QemuThread));
 666         env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 667         qemu_cond_init(env->halt_cond);
 668         qemu_thread_create(env->thread, tcg_cpu_thread_fn, env);
 669         while (env->created == 0)
 670             qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 671         tcg_cpu_thread = env->thread;
 672         tcg_halt_cond = env->halt_cond;
 673     } else {
 674         env->thread = tcg_cpu_thread;
 675         env->halt_cond = tcg_halt_cond;
 676     }
 677 }
 678
 679 static void kvm_start_vcpu(CPUState *env)
 680 {
 681     env->thread = qemu_mallocz(sizeof(QemuThread));
 682     env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 683     qemu_cond_init(env->halt_cond);
 684     qemu_thread_create(env->thread, kvm_cpu_thread_fn, env);
 685     while (env->created == 0)
 686         qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 687 }
 688
 689 void qemu_init_vcpu(void *_env)
 690 {
 691     CPUState *env = _env;
 692
 693     env->nr_cores = smp_cores;
 694     env->nr_threads = smp_threads;
 695     if (kvm_enabled())
 696         kvm_start_vcpu(env);
 697     else
 698         tcg_init_vcpu(env);
 699 }
 700
 701 void qemu_notify_event(void)
 702 {
 703     qemu_event_increment();
 704 }
 705
 706 static void qemu_system_vmstop_request(int reason)
 707 {
 708     vmstop_requested = reason;
 709     qemu_notify_event();
 710 }
 711
 712 void vm_stop(int reason)
 713 {
 714     QemuThread me;
 715     qemu_thread_self(&me);
 716
 717     if (!qemu_thread_equal(&me, &io_thread)) {
 718         qemu_system_vmstop_request(reason);
 719         /*
 720          * FIXME: should not return to device code in case
 721          * vm_stop() has been requested.
 722          */
 723         if (cpu_single_env) {
 724             cpu_exit(cpu_single_env);
 725             cpu_single_env->stop = 1;
 726         }
 727         return;
 728     }
 729     do_vm_stop(reason);
 730 }
 731
 732 #endif
 733
 734 static int qemu_cpu_exec(CPUState *env)
 735 {
 736     int ret;
 737 #ifdef CONFIG_PROFILER
 738     int64_t ti;
 739 #endif
 740
 741 #ifdef CONFIG_PROFILER
 742     ti = profile_getclock();
 743 #endif
 744     if (use_icount) {
 745         int64_t count;
 746         int decr;
 747         qemu_icount -= (env->icount_decr.u16.low + env->icount_extra);
 748         env->icount_decr.u16.low = 0;
 749         env->icount_extra = 0;
 750         count = qemu_icount_round (qemu_next_deadline());
 751         qemu_icount += count;
 752         decr = (count > 0xffff) ? 0xffff : count;
 753         count -= decr;
 754         env->icount_decr.u16.low = decr;
 755         env->icount_extra = count;
 756     }
 757     ret = cpu_exec(env);
 758 #ifdef CONFIG_PROFILER
 759     qemu_time += profile_getclock() - ti;
 760 #endif
 761     if (use_icount) {
 762         /* Fold pending instructions back into the
 763            instruction counter, and clear the interrupt flag.  */
 764         qemu_icount -= (env->icount_decr.u16.low
 765                         + env->icount_extra);
 766         env->icount_decr.u32 = 0;
 767         env->icount_extra = 0;
 768     }
 769     return ret;
 770 }
 771
 772 bool tcg_cpu_exec(void)
 773 {
 774     int ret = 0;
 775
 776     if (next_cpu == NULL)
 777         next_cpu = first_cpu;
 778     for (; next_cpu != NULL && !exit_request; next_cpu = next_cpu->next_cpu) {
 779         CPUState *env = cur_cpu = next_cpu;
 780
 781         qemu_clock_enable(vm_clock,
 782                           (cur_cpu->singlestep_enabled & SSTEP_NOTIMER) == 0);
 783
 784         if (qemu_alarm_pending())
 785             break;
 786         if (cpu_can_run(env))
 787             ret = qemu_cpu_exec(env);
 788         else if (env->stop)
 789             break;
 790
 791         if (ret == EXCP_DEBUG) {
 792             gdb_set_stop_cpu(env);
 793             debug_requested = EXCP_DEBUG;
 794             break;
 795         }
 796     }
 797     exit_request = 0;
 798     return tcg_has_work();
 799 }
 800
 801 void set_numa_modes(void)
 802 {
 803     CPUState *env;
 804     int i;
 805
 806     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 807         for (i = 0; i < nb_numa_nodes; i++) {
 808             if (node_cpumask[i] & (1 << env->cpu_index)) {
 809                 env->numa_node = i;
 810             }
 811         }
 812     }
 813 }
 814
 815 void set_cpu_log(const char *optarg)
 816 {
 817     int mask;
 818     const CPULogItem *item;
 819
 820     mask = cpu_str_to_log_mask(optarg);
 821     if (!mask) {
 822         printf("Log items (comma separated):\n");
 823         for (item = cpu_log_items; item->mask != 0; item++) {
 824             printf("%-10s %s\n", item->name, item->help);
 825         }
 826         exit(1);
 827     }
 828     cpu_set_log(mask);
 829 }
 830
 831 /* Return the virtual CPU time, based on the instruction counter.  */
 832 int64_t cpu_get_icount(void)
 833 {
 834     int64_t icount;
 835     CPUState *env = cpu_single_env;;
 836
 837     icount = qemu_icount;
 838     if (env) {
 839         if (!can_do_io(env)) {
 840             fprintf(stderr, "Bad clock read\n");
 841         }
 842         icount -= (env->icount_decr.u16.low + env->icount_extra);
 843     }
 844     return qemu_icount_bias + (icount << icount_time_shift);
 845 }
 846
 847 void list_cpus(FILE *f, int (*cpu_fprintf)(FILE *f, const char *fmt, ...),
 848                const char *optarg)
 849 {
 850     /* XXX: implement xxx_cpu_list for targets that still miss it */
 851 #if defined(cpu_list_id)
 852     cpu_list_id(f, cpu_fprintf, optarg);
 853 #elif defined(cpu_list)
 854     cpu_list(f, cpu_fprintf); /* deprecated */
 855 #endif
 856 }