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 #include "compatfd.h"
  37 #ifdef CONFIG_LINUX
  38 #include <sys/prctl.h>
  39 #endif
  40
  41 #ifdef SIGRTMIN
  42 #define SIG_IPI (SIGRTMIN+4)
  43 #else
  44 #define SIG_IPI SIGUSR1
  45 #endif
  46
  47 #ifndef PR_MCE_KILL
  48 #define PR_MCE_KILL 33
  49 #endif
  50
  51 static CPUState *next_cpu;
  52
  53 /***********************************************************/
  54 void hw_error(const char *fmt, ...)
  55 {
  56     va_list ap;
  57     CPUState *env;
  58
  59     va_start(ap, fmt);
  60     fprintf(stderr, "qemu: hardware error: ");
  61     vfprintf(stderr, fmt, ap);
  62     fprintf(stderr, "\n");
  63     for(env = first_cpu; env != NULL; env = env->next_cpu) {
  64         fprintf(stderr, "CPU #%d:\n", env->cpu_index);
  65 #ifdef TARGET_I386
  66         cpu_dump_state(env, stderr, fprintf, X86_DUMP_FPU);
  67 #else
  68         cpu_dump_state(env, stderr, fprintf, 0);
  69 #endif
  70     }
  71     va_end(ap);
  72     abort();
  73 }
  74
  75 void cpu_synchronize_all_states(void)
  76 {
  77     CPUState *cpu;
  78
  79     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  80         cpu_synchronize_state(cpu);
  81     }
  82 }
  83
  84 void cpu_synchronize_all_post_reset(void)
  85 {
  86     CPUState *cpu;
  87
  88     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  89         cpu_synchronize_post_reset(cpu);
  90     }
  91 }
  92
  93 void cpu_synchronize_all_post_init(void)
  94 {
  95     CPUState *cpu;
  96
  97     for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
  98         cpu_synchronize_post_init(cpu);
  99     }
 100 }
 101
 102 int cpu_is_stopped(CPUState *env)
 103 {
 104     return !vm_running || env->stopped;
 105 }
 106
 107 static void do_vm_stop(int reason)
 108 {
 109     if (vm_running) {
 110         cpu_disable_ticks();
 111         vm_running = 0;
 112         pause_all_vcpus();
 113         vm_state_notify(0, reason);
 114         qemu_aio_flush();
 115         bdrv_flush_all();
 116         monitor_protocol_event(QEVENT_STOP, NULL);
 117     }
 118 }
 119
 120 static int cpu_can_run(CPUState *env)
 121 {
 122     if (env->stop)
 123         return 0;
 124     if (env->stopped || !vm_running)
 125         return 0;
 126     return 1;
 127 }
 128
 129 static int cpu_has_work(CPUState *env)
 130 {
 131     if (env->stop)
 132         return 1;
 133     if (env->queued_work_first)
 134         return 1;
 135     if (env->stopped || !vm_running)
 136         return 0;
 137     if (!env->halted)
 138         return 1;
 139     if (qemu_cpu_has_work(env))
 140         return 1;
 141     return 0;
 142 }
 143
 144 static int any_cpu_has_work(void)
 145 {
 146     CPUState *env;
 147
 148     for (env = first_cpu; env != NULL; env = env->next_cpu)
 149         if (cpu_has_work(env))
 150             return 1;
 151     return 0;
 152 }
 153
 154 static void cpu_debug_handler(CPUState *env)
 155 {
 156     gdb_set_stop_cpu(env);
 157     debug_requested = EXCP_DEBUG;
 158     vm_stop(EXCP_DEBUG);
 159 }
 160
 161 #ifndef _WIN32
 162 static int io_thread_fd = -1;
 163
 164 static void qemu_event_increment(void)
 165 {
 166     /* Write 8 bytes to be compatible with eventfd.  */
 167     static const uint64_t val = 1;
 168     ssize_t ret;
 169
 170     if (io_thread_fd == -1)
 171         return;
 172
 173     do {
 174         ret = write(io_thread_fd, &val, sizeof(val));
 175     } while (ret < 0 && errno == EINTR);
 176
 177     /* EAGAIN is fine, a read must be pending.  */
 178     if (ret < 0 && errno != EAGAIN) {
 179         fprintf(stderr, "qemu_event_increment: write() filed: %s\n",
 180                 strerror(errno));
 181         exit (1);
 182     }
 183 }
 184
 185 static void qemu_event_read(void *opaque)
 186 {
 187     int fd = (unsigned long)opaque;
 188     ssize_t len;
 189     char buffer[512];
 190
 191     /* Drain the notify pipe.  For eventfd, only 8 bytes will be read.  */
 192     do {
 193         len = read(fd, buffer, sizeof(buffer));
 194     } while ((len == -1 && errno == EINTR) || len == sizeof(buffer));
 195 }
 196
 197 static int qemu_event_init(void)
 198 {
 199     int err;
 200     int fds[2];
 201
 202     err = qemu_eventfd(fds);
 203     if (err == -1)
 204         return -errno;
 205
 206     err = fcntl_setfl(fds[0], O_NONBLOCK);
 207     if (err < 0)
 208         goto fail;
 209
 210     err = fcntl_setfl(fds[1], O_NONBLOCK);
 211     if (err < 0)
 212         goto fail;
 213
 214     qemu_set_fd_handler2(fds[0], NULL, qemu_event_read, NULL,
 215                          (void *)(unsigned long)fds[0]);
 216
 217     io_thread_fd = fds[1];
 218     return 0;
 219
 220 fail:
 221     close(fds[0]);
 222     close(fds[1]);
 223     return err;
 224 }
 225
 226 static void dummy_signal(int sig)
 227 {
 228 }
 229
 230 #else /* _WIN32 */
 231
 232 HANDLE qemu_event_handle;
 233
 234 static void dummy_event_handler(void *opaque)
 235 {
 236 }
 237
 238 static int qemu_event_init(void)
 239 {
 240     qemu_event_handle = CreateEvent(NULL, FALSE, FALSE, NULL);
 241     if (!qemu_event_handle) {
 242         fprintf(stderr, "Failed CreateEvent: %ld\n", GetLastError());
 243         return -1;
 244     }
 245     qemu_add_wait_object(qemu_event_handle, dummy_event_handler, NULL);
 246     return 0;
 247 }
 248
 249 static void qemu_event_increment(void)
 250 {
 251     if (!SetEvent(qemu_event_handle)) {
 252         fprintf(stderr, "qemu_event_increment: SetEvent failed: %ld\n",
 253                 GetLastError());
 254         exit (1);
 255     }
 256 }
 257 #endif /* _WIN32 */
 258
 259 #ifndef CONFIG_IOTHREAD
 260 static void qemu_kvm_init_cpu_signals(CPUState *env)
 261 {
 262 #ifndef _WIN32
 263     int r;
 264     sigset_t set;
 265     struct sigaction sigact;
 266
 267     memset(&sigact, 0, sizeof(sigact));
 268     sigact.sa_handler = dummy_signal;
 269     sigaction(SIG_IPI, &sigact, NULL);
 270
 271     sigemptyset(&set);
 272     sigaddset(&set, SIG_IPI);
 273     pthread_sigmask(SIG_BLOCK, &set, NULL);
 274
 275     pthread_sigmask(SIG_BLOCK, NULL, &set);
 276     sigdelset(&set, SIG_IPI);
 277     sigdelset(&set, SIGBUS);
 278     r = kvm_set_signal_mask(env, &set);
 279     if (r) {
 280         fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));
 281         exit(1);
 282     }
 283 #endif
 284 }
 285
 286 int qemu_init_main_loop(void)
 287 {
 288     cpu_set_debug_excp_handler(cpu_debug_handler);
 289
 290     return qemu_event_init();
 291 }
 292
 293 void qemu_main_loop_start(void)
 294 {
 295 }
 296
 297 void qemu_init_vcpu(void *_env)
 298 {
 299     CPUState *env = _env;
 300     int r;
 301
 302     env->nr_cores = smp_cores;
 303     env->nr_threads = smp_threads;
 304
 305     if (kvm_enabled()) {
 306         r = kvm_init_vcpu(env);
 307         if (r < 0) {
 308             fprintf(stderr, "kvm_init_vcpu failed: %s\n", strerror(-r));
 309             exit(1);
 310         }
 311         qemu_kvm_init_cpu_signals(env);
 312     }
 313 }
 314
 315 int qemu_cpu_self(void *env)
 316 {
 317     return 1;
 318 }
 319
 320 void run_on_cpu(CPUState *env, void (*func)(void *data), void *data)
 321 {
 322     func(data);
 323 }
 324
 325 void resume_all_vcpus(void)
 326 {
 327 }
 328
 329 void pause_all_vcpus(void)
 330 {
 331 }
 332
 333 void qemu_cpu_kick(void *env)
 334 {
 335     return;
 336 }
 337
 338 void qemu_notify_event(void)
 339 {
 340     CPUState *env = cpu_single_env;
 341
 342     qemu_event_increment ();
 343     if (env) {
 344         cpu_exit(env);
 345     }
 346     if (next_cpu && env != next_cpu) {
 347         cpu_exit(next_cpu);
 348     }
 349     exit_request = 1;
 350 }
 351
 352 void qemu_mutex_lock_iothread(void) {}
 353 void qemu_mutex_unlock_iothread(void) {}
 354
 355 void cpu_stop_current(void)
 356 {
 357 }
 358
 359 void vm_stop(int reason)
 360 {
 361     do_vm_stop(reason);
 362 }
 363
 364 #else /* CONFIG_IOTHREAD */
 365
 366 #include "qemu-thread.h"
 367
 368 QemuMutex qemu_global_mutex;
 369 static QemuMutex qemu_fair_mutex;
 370
 371 static QemuThread io_thread;
 372
 373 static QemuThread *tcg_cpu_thread;
 374 static QemuCond *tcg_halt_cond;
 375
 376 static int qemu_system_ready;
 377 /* cpu creation */
 378 static QemuCond qemu_cpu_cond;
 379 /* system init */
 380 static QemuCond qemu_system_cond;
 381 static QemuCond qemu_pause_cond;
 382 static QemuCond qemu_work_cond;
 383
 384 /* If we have signalfd, we mask out the signals we want to handle and then
 385  * use signalfd to listen for them.  We rely on whatever the current signal
 386  * handler is to dispatch the signals when we receive them.
 387  */
 388 static void sigfd_handler(void *opaque)
 389 {
 390     int fd = (unsigned long) opaque;
 391     struct qemu_signalfd_siginfo info;
 392     struct sigaction action;
 393     ssize_t len;
 394
 395     while (1) {
 396         do {
 397             len = read(fd, &info, sizeof(info));
 398         } while (len == -1 && errno == EINTR);
 399
 400         if (len == -1 && errno == EAGAIN) {
 401             break;
 402         }
 403
 404         if (len != sizeof(info)) {
 405             printf("read from sigfd returned %zd: %m\n", len);
 406             return;
 407         }
 408
 409         sigaction(info.ssi_signo, NULL, &action);
 410         if ((action.sa_flags & SA_SIGINFO) && action.sa_sigaction) {
 411             action.sa_sigaction(info.ssi_signo,
 412                                 (siginfo_t *)&info, NULL);
 413         } else if (action.sa_handler) {
 414             action.sa_handler(info.ssi_signo);
 415         }
 416     }
 417 }
 418
 419 static void cpu_signal(int sig)
 420 {
 421     if (cpu_single_env) {
 422         cpu_exit(cpu_single_env);
 423     }
 424     exit_request = 1;
 425 }
 426
 427 static void qemu_kvm_init_cpu_signals(CPUState *env)
 428 {
 429     int r;
 430     sigset_t set;
 431     struct sigaction sigact;
 432
 433     memset(&sigact, 0, sizeof(sigact));
 434     sigact.sa_handler = dummy_signal;
 435     sigaction(SIG_IPI, &sigact, NULL);
 436
 437     pthread_sigmask(SIG_BLOCK, NULL, &set);
 438     sigdelset(&set, SIG_IPI);
 439     sigdelset(&set, SIGBUS);
 440     r = kvm_set_signal_mask(env, &set);
 441     if (r) {
 442         fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));
 443         exit(1);
 444     }
 445 }
 446
 447 static void qemu_tcg_init_cpu_signals(void)
 448 {
 449     sigset_t set;
 450     struct sigaction sigact;
 451
 452     memset(&sigact, 0, sizeof(sigact));
 453     sigact.sa_handler = cpu_signal;
 454     sigaction(SIG_IPI, &sigact, NULL);
 455
 456     sigemptyset(&set);
 457     sigaddset(&set, SIG_IPI);
 458     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 459 }
 460
 461 static void sigbus_handler(int n, struct qemu_signalfd_siginfo *siginfo,
 462                            void *ctx);
 463
 464 static sigset_t block_io_signals(void)
 465 {
 466     sigset_t set;
 467     struct sigaction action;
 468
 469     /* SIGUSR2 used by posix-aio-compat.c */
 470     sigemptyset(&set);
 471     sigaddset(&set, SIGUSR2);
 472     pthread_sigmask(SIG_UNBLOCK, &set, NULL);
 473
 474     sigemptyset(&set);
 475     sigaddset(&set, SIGIO);
 476     sigaddset(&set, SIGALRM);
 477     sigaddset(&set, SIG_IPI);
 478     sigaddset(&set, SIGBUS);
 479     pthread_sigmask(SIG_BLOCK, &set, NULL);
 480
 481     memset(&action, 0, sizeof(action));
 482     action.sa_flags = SA_SIGINFO;
 483     action.sa_sigaction = (void (*)(int, siginfo_t*, void*))sigbus_handler;
 484     sigaction(SIGBUS, &action, NULL);
 485     prctl(PR_MCE_KILL, 1, 1, 0, 0);
 486
 487     return set;
 488 }
 489
 490 static int qemu_signalfd_init(sigset_t mask)
 491 {
 492     int sigfd;
 493
 494     sigfd = qemu_signalfd(&mask);
 495     if (sigfd == -1) {
 496         fprintf(stderr, "failed to create signalfd\n");
 497         return -errno;
 498     }
 499
 500     fcntl_setfl(sigfd, O_NONBLOCK);
 501
 502     qemu_set_fd_handler2(sigfd, NULL, sigfd_handler, NULL,
 503                          (void *)(unsigned long) sigfd);
 504
 505     return 0;
 506 }
 507
 508 int qemu_init_main_loop(void)
 509 {
 510     int ret;
 511     sigset_t blocked_signals;
 512
 513     cpu_set_debug_excp_handler(cpu_debug_handler);
 514
 515     blocked_signals = block_io_signals();
 516
 517     ret = qemu_signalfd_init(blocked_signals);
 518     if (ret)
 519         return ret;
 520
 521     /* Note eventfd must be drained before signalfd handlers run */
 522     ret = qemu_event_init();
 523     if (ret)
 524         return ret;
 525
 526     qemu_cond_init(&qemu_pause_cond);
 527     qemu_cond_init(&qemu_system_cond);
 528     qemu_mutex_init(&qemu_fair_mutex);
 529     qemu_mutex_init(&qemu_global_mutex);
 530     qemu_mutex_lock(&qemu_global_mutex);
 531
 532     qemu_thread_self(&io_thread);
 533
 534     return 0;
 535 }
 536
 537 void qemu_main_loop_start(void)
 538 {
 539     qemu_system_ready = 1;
 540     qemu_cond_broadcast(&qemu_system_cond);
 541 }
 542
 543 void run_on_cpu(CPUState *env, void (*func)(void *data), void *data)
 544 {
 545     struct qemu_work_item wi;
 546
 547     if (qemu_cpu_self(env)) {
 548         func(data);
 549         return;
 550     }
 551
 552     wi.func = func;
 553     wi.data = data;
 554     if (!env->queued_work_first)
 555         env->queued_work_first = &wi;
 556     else
 557         env->queued_work_last->next = &wi;
 558     env->queued_work_last = &wi;
 559     wi.next = NULL;
 560     wi.done = false;
 561
 562     qemu_cpu_kick(env);
 563     while (!wi.done) {
 564         CPUState *self_env = cpu_single_env;
 565
 566         qemu_cond_wait(&qemu_work_cond, &qemu_global_mutex);
 567         cpu_single_env = self_env;
 568     }
 569 }
 570
 571 static void flush_queued_work(CPUState *env)
 572 {
 573     struct qemu_work_item *wi;
 574
 575     if (!env->queued_work_first)
 576         return;
 577
 578     while ((wi = env->queued_work_first)) {
 579         env->queued_work_first = wi->next;
 580         wi->func(wi->data);
 581         wi->done = true;
 582     }
 583     env->queued_work_last = NULL;
 584     qemu_cond_broadcast(&qemu_work_cond);
 585 }
 586
 587 static void qemu_wait_io_event_common(CPUState *env)
 588 {
 589     if (env->stop) {
 590         env->stop = 0;
 591         env->stopped = 1;
 592         qemu_cond_signal(&qemu_pause_cond);
 593     }
 594     flush_queued_work(env);
 595     env->thread_kicked = false;
 596 }
 597
 598 static void qemu_tcg_wait_io_event(void)
 599 {
 600     CPUState *env;
 601
 602     while (!any_cpu_has_work())
 603         qemu_cond_timedwait(tcg_halt_cond, &qemu_global_mutex, 1000);
 604
 605     qemu_mutex_unlock(&qemu_global_mutex);
 606
 607     /*
 608      * Users of qemu_global_mutex can be starved, having no chance
 609      * to acquire it since this path will get to it first.
 610      * So use another lock to provide fairness.
 611      */
 612     qemu_mutex_lock(&qemu_fair_mutex);
 613     qemu_mutex_unlock(&qemu_fair_mutex);
 614
 615     qemu_mutex_lock(&qemu_global_mutex);
 616
 617     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 618         qemu_wait_io_event_common(env);
 619     }
 620 }
 621
 622 static void sigbus_reraise(void)
 623 {
 624     sigset_t set;
 625     struct sigaction action;
 626
 627     memset(&action, 0, sizeof(action));
 628     action.sa_handler = SIG_DFL;
 629     if (!sigaction(SIGBUS, &action, NULL)) {
 630         raise(SIGBUS);
 631         sigemptyset(&set);
 632         sigaddset(&set, SIGBUS);
 633         sigprocmask(SIG_UNBLOCK, &set, NULL);
 634     }
 635     perror("Failed to re-raise SIGBUS!\n");
 636     abort();
 637 }
 638
 639 static void sigbus_handler(int n, struct qemu_signalfd_siginfo *siginfo,
 640                            void *ctx)
 641 {
 642     if (kvm_on_sigbus(siginfo->ssi_code, (void *)(intptr_t)siginfo->ssi_addr)) {
 643         sigbus_reraise();
 644     }
 645 }
 646
 647 static void qemu_kvm_eat_signals(CPUState *env)
 648 {
 649     struct timespec ts = { 0, 0 };
 650     siginfo_t siginfo;
 651     sigset_t waitset;
 652     sigset_t chkset;
 653     int r;
 654
 655     sigemptyset(&waitset);
 656     sigaddset(&waitset, SIG_IPI);
 657     sigaddset(&waitset, SIGBUS);
 658
 659     do {
 660         r = sigtimedwait(&waitset, &siginfo, &ts);
 661         if (r == -1 && !(errno == EAGAIN || errno == EINTR)) {
 662             perror("sigtimedwait");
 663             exit(1);
 664         }
 665
 666         switch (r) {
 667         case SIGBUS:
 668             if (kvm_on_sigbus_vcpu(env, siginfo.si_code, siginfo.si_addr)) {
 669                 sigbus_reraise();
 670             }
 671             break;
 672         default:
 673             break;
 674         }
 675
 676         r = sigpending(&chkset);
 677         if (r == -1) {
 678             perror("sigpending");
 679             exit(1);
 680         }
 681     } while (sigismember(&chkset, SIG_IPI) || sigismember(&chkset, SIGBUS));
 682 }
 683
 684 static void qemu_kvm_wait_io_event(CPUState *env)
 685 {
 686     while (!cpu_has_work(env))
 687         qemu_cond_timedwait(env->halt_cond, &qemu_global_mutex, 1000);
 688
 689     qemu_kvm_eat_signals(env);
 690     qemu_wait_io_event_common(env);
 691 }
 692
 693 static int qemu_cpu_exec(CPUState *env);
 694
 695 static void *kvm_cpu_thread_fn(void *arg)
 696 {
 697     CPUState *env = arg;
 698     int r;
 699
 700     qemu_mutex_lock(&qemu_global_mutex);
 701     qemu_thread_self(env->thread);
 702
 703     r = kvm_init_vcpu(env);
 704     if (r < 0) {
 705         fprintf(stderr, "kvm_init_vcpu failed: %s\n", strerror(-r));
 706         exit(1);
 707     }
 708
 709     qemu_kvm_init_cpu_signals(env);
 710
 711     /* signal CPU creation */
 712     env->created = 1;
 713     qemu_cond_signal(&qemu_cpu_cond);
 714
 715     /* and wait for machine initialization */
 716     while (!qemu_system_ready)
 717         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 718
 719     while (1) {
 720         if (cpu_can_run(env))
 721             qemu_cpu_exec(env);
 722         qemu_kvm_wait_io_event(env);
 723     }
 724
 725     return NULL;
 726 }
 727
 728 static void *tcg_cpu_thread_fn(void *arg)
 729 {
 730     CPUState *env = arg;
 731
 732     qemu_tcg_init_cpu_signals();
 733     qemu_thread_self(env->thread);
 734
 735     /* signal CPU creation */
 736     qemu_mutex_lock(&qemu_global_mutex);
 737     for (env = first_cpu; env != NULL; env = env->next_cpu)
 738         env->created = 1;
 739     qemu_cond_signal(&qemu_cpu_cond);
 740
 741     /* and wait for machine initialization */
 742     while (!qemu_system_ready)
 743         qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
 744
 745     while (1) {
 746         cpu_exec_all();
 747         qemu_tcg_wait_io_event();
 748     }
 749
 750     return NULL;
 751 }
 752
 753 void qemu_cpu_kick(void *_env)
 754 {
 755     CPUState *env = _env;
 756     qemu_cond_broadcast(env->halt_cond);
 757     if (!env->thread_kicked) {
 758         qemu_thread_signal(env->thread, SIG_IPI);
 759         env->thread_kicked = true;
 760     }
 761 }
 762
 763 int qemu_cpu_self(void *_env)
 764 {
 765     CPUState *env = _env;
 766     QemuThread this;
 767
 768     qemu_thread_self(&this);
 769
 770     return qemu_thread_equal(&this, env->thread);
 771 }
 772
 773 void qemu_mutex_lock_iothread(void)
 774 {
 775     if (kvm_enabled()) {
 776         qemu_mutex_lock(&qemu_global_mutex);
 777     } else {
 778         qemu_mutex_lock(&qemu_fair_mutex);
 779         if (qemu_mutex_trylock(&qemu_global_mutex)) {
 780             qemu_thread_signal(tcg_cpu_thread, SIG_IPI);
 781             qemu_mutex_lock(&qemu_global_mutex);
 782         }
 783         qemu_mutex_unlock(&qemu_fair_mutex);
 784     }
 785 }
 786
 787 void qemu_mutex_unlock_iothread(void)
 788 {
 789     qemu_mutex_unlock(&qemu_global_mutex);
 790 }
 791
 792 static int all_vcpus_paused(void)
 793 {
 794     CPUState *penv = first_cpu;
 795
 796     while (penv) {
 797         if (!penv->stopped)
 798             return 0;
 799         penv = (CPUState *)penv->next_cpu;
 800     }
 801
 802     return 1;
 803 }
 804
 805 void pause_all_vcpus(void)
 806 {
 807     CPUState *penv = first_cpu;
 808
 809     while (penv) {
 810         penv->stop = 1;
 811         qemu_cpu_kick(penv);
 812         penv = (CPUState *)penv->next_cpu;
 813     }
 814
 815     while (!all_vcpus_paused()) {
 816         qemu_cond_timedwait(&qemu_pause_cond, &qemu_global_mutex, 100);
 817         penv = first_cpu;
 818         while (penv) {
 819             qemu_cpu_kick(penv);
 820             penv = (CPUState *)penv->next_cpu;
 821         }
 822     }
 823 }
 824
 825 void resume_all_vcpus(void)
 826 {
 827     CPUState *penv = first_cpu;
 828
 829     while (penv) {
 830         penv->stop = 0;
 831         penv->stopped = 0;
 832         qemu_cpu_kick(penv);
 833         penv = (CPUState *)penv->next_cpu;
 834     }
 835 }
 836
 837 static void tcg_init_vcpu(void *_env)
 838 {
 839     CPUState *env = _env;
 840     /* share a single thread for all cpus with TCG */
 841     if (!tcg_cpu_thread) {
 842         env->thread = qemu_mallocz(sizeof(QemuThread));
 843         env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 844         qemu_cond_init(env->halt_cond);
 845         qemu_thread_create(env->thread, tcg_cpu_thread_fn, env);
 846         while (env->created == 0)
 847             qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 848         tcg_cpu_thread = env->thread;
 849         tcg_halt_cond = env->halt_cond;
 850     } else {
 851         env->thread = tcg_cpu_thread;
 852         env->halt_cond = tcg_halt_cond;
 853     }
 854 }
 855
 856 static void kvm_start_vcpu(CPUState *env)
 857 {
 858     env->thread = qemu_mallocz(sizeof(QemuThread));
 859     env->halt_cond = qemu_mallocz(sizeof(QemuCond));
 860     qemu_cond_init(env->halt_cond);
 861     qemu_thread_create(env->thread, kvm_cpu_thread_fn, env);
 862     while (env->created == 0)
 863         qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
 864 }
 865
 866 void qemu_init_vcpu(void *_env)
 867 {
 868     CPUState *env = _env;
 869
 870     env->nr_cores = smp_cores;
 871     env->nr_threads = smp_threads;
 872     if (kvm_enabled())
 873         kvm_start_vcpu(env);
 874     else
 875         tcg_init_vcpu(env);
 876 }
 877
 878 void qemu_notify_event(void)
 879 {
 880     qemu_event_increment();
 881 }
 882
 883 static void qemu_system_vmstop_request(int reason)
 884 {
 885     vmstop_requested = reason;
 886     qemu_notify_event();
 887 }
 888
 889 void cpu_stop_current(void)
 890 {
 891     if (cpu_single_env) {
 892         cpu_single_env->stopped = 1;
 893         cpu_exit(cpu_single_env);
 894     }
 895 }
 896
 897 void vm_stop(int reason)
 898 {
 899     QemuThread me;
 900     qemu_thread_self(&me);
 901
 902     if (!qemu_thread_equal(&me, &io_thread)) {
 903         qemu_system_vmstop_request(reason);
 904         /*
 905          * FIXME: should not return to device code in case
 906          * vm_stop() has been requested.
 907          */
 908         cpu_stop_current();
 909         return;
 910     }
 911     do_vm_stop(reason);
 912 }
 913
 914 #endif
 915
 916 static int qemu_cpu_exec(CPUState *env)
 917 {
 918     int ret;
 919 #ifdef CONFIG_PROFILER
 920     int64_t ti;
 921 #endif
 922
 923 #ifdef CONFIG_PROFILER
 924     ti = profile_getclock();
 925 #endif
 926     if (use_icount) {
 927         int64_t count;
 928         int decr;
 929         qemu_icount -= (env->icount_decr.u16.low + env->icount_extra);
 930         env->icount_decr.u16.low = 0;
 931         env->icount_extra = 0;
 932         count = qemu_icount_round (qemu_next_deadline());
 933         qemu_icount += count;
 934         decr = (count > 0xffff) ? 0xffff : count;
 935         count -= decr;
 936         env->icount_decr.u16.low = decr;
 937         env->icount_extra = count;
 938     }
 939     ret = cpu_exec(env);
 940 #ifdef CONFIG_PROFILER
 941     qemu_time += profile_getclock() - ti;
 942 #endif
 943     if (use_icount) {
 944         /* Fold pending instructions back into the
 945            instruction counter, and clear the interrupt flag.  */
 946         qemu_icount -= (env->icount_decr.u16.low
 947                         + env->icount_extra);
 948         env->icount_decr.u32 = 0;
 949         env->icount_extra = 0;
 950     }
 951     return ret;
 952 }
 953
 954 bool cpu_exec_all(void)
 955 {
 956     if (next_cpu == NULL)
 957         next_cpu = first_cpu;
 958     for (; next_cpu != NULL && !exit_request; next_cpu = next_cpu->next_cpu) {
 959         CPUState *env = next_cpu;
 960
 961         qemu_clock_enable(vm_clock,
 962                           (env->singlestep_enabled & SSTEP_NOTIMER) == 0);
 963
 964         if (qemu_alarm_pending())
 965             break;
 966         if (cpu_can_run(env)) {
 967             if (qemu_cpu_exec(env) == EXCP_DEBUG) {
 968                 break;
 969             }
 970         } else if (env->stop) {
 971             break;
 972         }
 973     }
 974     exit_request = 0;
 975     return any_cpu_has_work();
 976 }
 977
 978 void set_numa_modes(void)
 979 {
 980     CPUState *env;
 981     int i;
 982
 983     for (env = first_cpu; env != NULL; env = env->next_cpu) {
 984         for (i = 0; i < nb_numa_nodes; i++) {
 985             if (node_cpumask[i] & (1 << env->cpu_index)) {
 986                 env->numa_node = i;
 987             }
 988         }
 989     }
 990 }
 991
 992 void set_cpu_log(const char *optarg)
 993 {
 994     int mask;
 995     const CPULogItem *item;
 996
 997     mask = cpu_str_to_log_mask(optarg);
 998     if (!mask) {
 999         printf("Log items (comma separated):\n");
1000         for (item = cpu_log_items; item->mask != 0; item++) {
1001             printf("%-10s %s\n", item->name, item->help);
1002         }
1003         exit(1);
1004     }
1005     cpu_set_log(mask);
1006 }
1007
1008 /* Return the virtual CPU time, based on the instruction counter.  */
1009 int64_t cpu_get_icount(void)
1010 {
1011     int64_t icount;
1012     CPUState *env = cpu_single_env;;
1013
1014     icount = qemu_icount;
1015     if (env) {
1016         if (!can_do_io(env)) {
1017             fprintf(stderr, "Bad clock read\n");
1018         }
1019         icount -= (env->icount_decr.u16.low + env->icount_extra);
1020     }
1021     return qemu_icount_bias + (icount << icount_time_shift);
1022 }
1023
1024 void list_cpus(FILE *f, fprintf_function cpu_fprintf, const char *optarg)
1025 {
1026     /* XXX: implement xxx_cpu_list for targets that still miss it */
1027 #if defined(cpu_list_id)
1028     cpu_list_id(f, cpu_fprintf, optarg);
1029 #elif defined(cpu_list)
1030     cpu_list(f, cpu_fprintf); /* deprecated */
1031 #endif
1032 }