LXR qemu/accel/dummy-cpus.c

   1/*
   2 * Dummy cpu thread code
   3 *
   4 * Copyright IBM, Corp. 2011
   5 *
   6 * Authors:
   7 *  Anthony Liguori   <aliguori@us.ibm.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10 * See the COPYING file in the top-level directory.
  11 *
  12 */
  13
  14#include "qemu/osdep.h"
  15#include "qemu/rcu.h"
  16#include "sysemu/cpus.h"
  17#include "qemu/guest-random.h"
  18#include "qemu/main-loop.h"
  19#include "hw/core/cpu.h"
  20
  21static void *dummy_cpu_thread_fn(void *arg)
  22{
  23    CPUState *cpu = arg;
  24    sigset_t waitset;
  25    int r;
  26
  27    rcu_register_thread();
  28
  29    qemu_mutex_lock_iothread();
  30    qemu_thread_get_self(cpu->thread);
  31    cpu->thread_id = qemu_get_thread_id();
  32    cpu->can_do_io = 1;
  33    current_cpu = cpu;
  34
  35    sigemptyset(&waitset);
  36    sigaddset(&waitset, SIG_IPI);
  37
  38    /* signal CPU creation */
  39    cpu_thread_signal_created(cpu);
  40    qemu_guest_random_seed_thread_part2(cpu->random_seed);
  41
  42    do {
  43        qemu_mutex_unlock_iothread();
  44        do {
  45            int sig;
  46            r = sigwait(&waitset, &sig);
  47        } while (r == -1 && (errno == EAGAIN || errno == EINTR));
  48        if (r == -1) {
  49            perror("sigwait");
  50            exit(1);
  51        }
  52        qemu_mutex_lock_iothread();
  53        qemu_wait_io_event(cpu);
  54    } while (!cpu->unplug);
  55
  56    qemu_mutex_unlock_iothread();
  57    rcu_unregister_thread();
  58    return NULL;
  59}
  60
  61void dummy_start_vcpu_thread(CPUState *cpu)
  62{
  63    char thread_name[VCPU_THREAD_NAME_SIZE];
  64
  65    cpu->thread = g_malloc0(sizeof(QemuThread));
  66    cpu->halt_cond = g_malloc0(sizeof(QemuCond));
  67    qemu_cond_init(cpu->halt_cond);
  68    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/DUMMY",
  69             cpu->cpu_index);
  70    qemu_thread_create(cpu->thread, thread_name, dummy_cpu_thread_fn, cpu,
  71                       QEMU_THREAD_JOINABLE);
  72}
  73