+void vm_stop(int reason)
+{
+ do_vm_stop(reason);
+}
+
+#else /* CONFIG_IOTHREAD */
+
+#include "qemu-thread.h"
+
+QemuMutex qemu_global_mutex;
+static QemuMutex qemu_fair_mutex;
+
+static QemuThread io_thread;
+
+static QemuThread *tcg_cpu_thread;
+static QemuCond *tcg_halt_cond;
+
+static int qemu_system_ready;
+/* cpu creation */
+static QemuCond qemu_cpu_cond;
+/* system init */
+static QemuCond qemu_system_cond;
+static QemuCond qemu_pause_cond;
+
+static void block_io_signals(void);
+static void unblock_io_signals(void);
+static int tcg_has_work(void);
+
+static int qemu_init_main_loop(void)
+{
+ int ret;
+
+ ret = qemu_event_init();
+ if (ret)
+ return ret;
+
+ qemu_cond_init(&qemu_pause_cond);
+ qemu_mutex_init(&qemu_fair_mutex);
+ qemu_mutex_init(&qemu_global_mutex);
+ qemu_mutex_lock(&qemu_global_mutex);
+
+ unblock_io_signals();
+ qemu_thread_self(&io_thread);
+
+ return 0;
+}
+
+static void qemu_wait_io_event(CPUState *env)
+{
+ while (!tcg_has_work())
+ qemu_cond_timedwait(env->halt_cond, &qemu_global_mutex, 1000);
+
+ qemu_mutex_unlock(&qemu_global_mutex);
+
+ /*
+ * Users of qemu_global_mutex can be starved, having no chance
+ * to acquire it since this path will get to it first.
+ * So use another lock to provide fairness.
+ */
+ qemu_mutex_lock(&qemu_fair_mutex);
+ qemu_mutex_unlock(&qemu_fair_mutex);
+
+ qemu_mutex_lock(&qemu_global_mutex);
+ if (env->stop) {
+ env->stop = 0;
+ env->stopped = 1;
+ qemu_cond_signal(&qemu_pause_cond);
+ }
+}
+
+static int qemu_cpu_exec(CPUState *env);
+
+static void *kvm_cpu_thread_fn(void *arg)
+{
+ CPUState *env = arg;
+
+ block_io_signals();
+ qemu_thread_self(env->thread);
+
+ /* signal CPU creation */
+ qemu_mutex_lock(&qemu_global_mutex);
+ env->created = 1;
+ qemu_cond_signal(&qemu_cpu_cond);
+
+ /* and wait for machine initialization */
+ while (!qemu_system_ready)
+ qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
+
+ while (1) {
+ if (cpu_can_run(env))
+ qemu_cpu_exec(env);
+ qemu_wait_io_event(env);
+ }
+
+ return NULL;
+}
+
+static void tcg_cpu_exec(void);
+
+static void *tcg_cpu_thread_fn(void *arg)
+{
+ CPUState *env = arg;
+
+ block_io_signals();
+ qemu_thread_self(env->thread);
+
+ /* signal CPU creation */
+ qemu_mutex_lock(&qemu_global_mutex);
+ for (env = first_cpu; env != NULL; env = env->next_cpu)
+ env->created = 1;
+ qemu_cond_signal(&qemu_cpu_cond);
+
+ /* and wait for machine initialization */
+ while (!qemu_system_ready)
+ qemu_cond_timedwait(&qemu_system_cond, &qemu_global_mutex, 100);
+
+ while (1) {
+ tcg_cpu_exec();
+ qemu_wait_io_event(cur_cpu);
+ }
+
+ return NULL;
+}
+
+void qemu_cpu_kick(void *_env)
+{
+ CPUState *env = _env;
+ qemu_cond_broadcast(env->halt_cond);
+ if (kvm_enabled())
+ qemu_thread_signal(env->thread, SIGUSR1);
+}
+
+int qemu_cpu_self(void *env)
+{
+ return (cpu_single_env != NULL);
+}
+
+static void cpu_signal(int sig)
+{
+ if (cpu_single_env)
+ cpu_exit(cpu_single_env);
+}
+
+static void block_io_signals(void)
+{
+ sigset_t set;
+ struct sigaction sigact;
+
+ sigemptyset(&set);
+ sigaddset(&set, SIGUSR2);
+ sigaddset(&set, SIGIO);
+ sigaddset(&set, SIGALRM);
+ pthread_sigmask(SIG_BLOCK, &set, NULL);
+
+ sigemptyset(&set);
+ sigaddset(&set, SIGUSR1);
+ pthread_sigmask(SIG_UNBLOCK, &set, NULL);
+
+ memset(&sigact, 0, sizeof(sigact));
+ sigact.sa_handler = cpu_signal;
+ sigaction(SIGUSR1, &sigact, NULL);
+}
+
+static void unblock_io_signals(void)
+{
+ sigset_t set;
+
+ sigemptyset(&set);
+ sigaddset(&set, SIGUSR2);
+ sigaddset(&set, SIGIO);
+ sigaddset(&set, SIGALRM);
+ pthread_sigmask(SIG_UNBLOCK, &set, NULL);
+
+ sigemptyset(&set);
+ sigaddset(&set, SIGUSR1);
+ pthread_sigmask(SIG_BLOCK, &set, NULL);
+}
+
+static void qemu_signal_lock(unsigned int msecs)
+{
+ qemu_mutex_lock(&qemu_fair_mutex);
+
+ while (qemu_mutex_trylock(&qemu_global_mutex)) {
+ qemu_thread_signal(tcg_cpu_thread, SIGUSR1);
+ if (!qemu_mutex_timedlock(&qemu_global_mutex, msecs))
+ break;
+ }
+ qemu_mutex_unlock(&qemu_fair_mutex);
+}
+
+static void qemu_mutex_lock_iothread(void)
+{
+ if (kvm_enabled()) {
+ qemu_mutex_lock(&qemu_fair_mutex);
+ qemu_mutex_lock(&qemu_global_mutex);
+ qemu_mutex_unlock(&qemu_fair_mutex);
+ } else
+ qemu_signal_lock(100);
+}
+
+static void qemu_mutex_unlock_iothread(void)
+{
+ qemu_mutex_unlock(&qemu_global_mutex);
+}
+
+static int all_vcpus_paused(void)
+{
+ CPUState *penv = first_cpu;
+
+ while (penv) {
+ if (!penv->stopped)
+ return 0;
+ penv = (CPUState *)penv->next_cpu;
+ }
+
+ return 1;
+}
+
+static void pause_all_vcpus(void)
+{
+ CPUState *penv = first_cpu;
+
+ while (penv) {
+ penv->stop = 1;
+ qemu_thread_signal(penv->thread, SIGUSR1);
+ qemu_cpu_kick(penv);
+ penv = (CPUState *)penv->next_cpu;
+ }
+
+ while (!all_vcpus_paused()) {
+ qemu_cond_timedwait(&qemu_pause_cond, &qemu_global_mutex, 100);
+ penv = first_cpu;
+ while (penv) {
+ qemu_thread_signal(penv->thread, SIGUSR1);
+ penv = (CPUState *)penv->next_cpu;
+ }
+ }
+}
+
+static void resume_all_vcpus(void)
+{
+ CPUState *penv = first_cpu;
+
+ while (penv) {
+ penv->stop = 0;
+ penv->stopped = 0;
+ qemu_thread_signal(penv->thread, SIGUSR1);
+ qemu_cpu_kick(penv);
+ penv = (CPUState *)penv->next_cpu;
+ }
+}
+
+static void tcg_init_vcpu(void *_env)
+{
+ CPUState *env = _env;
+ /* share a single thread for all cpus with TCG */
+ if (!tcg_cpu_thread) {
+ env->thread = qemu_mallocz(sizeof(QemuThread));
+ env->halt_cond = qemu_mallocz(sizeof(QemuCond));
+ qemu_cond_init(env->halt_cond);
+ qemu_thread_create(env->thread, tcg_cpu_thread_fn, env);
+ while (env->created == 0)
+ qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
+ tcg_cpu_thread = env->thread;
+ tcg_halt_cond = env->halt_cond;
+ } else {
+ env->thread = tcg_cpu_thread;
+ env->halt_cond = tcg_halt_cond;
+ }
+}
+
+static void kvm_start_vcpu(CPUState *env)
+{
+ kvm_init_vcpu(env);
+ env->thread = qemu_mallocz(sizeof(QemuThread));
+ env->halt_cond = qemu_mallocz(sizeof(QemuCond));
+ qemu_cond_init(env->halt_cond);
+ qemu_thread_create(env->thread, kvm_cpu_thread_fn, env);
+ while (env->created == 0)
+ qemu_cond_timedwait(&qemu_cpu_cond, &qemu_global_mutex, 100);
+}
+
+void qemu_init_vcpu(void *_env)
+{
+ CPUState *env = _env;
+
+ if (kvm_enabled())
+ kvm_start_vcpu(env);
+ else
+ tcg_init_vcpu(env);
+}
+
+void qemu_notify_event(void)
+{
+ qemu_event_increment();
+}
+
+void vm_stop(int reason)
+{
+ QemuThread me;
+ qemu_thread_self(&me);
+
+ if (!qemu_thread_equal(&me, &io_thread)) {
+ qemu_system_vmstop_request(reason);
+ /*
+ * FIXME: should not return to device code in case
+ * vm_stop() has been requested.
+ */
+ if (cpu_single_env) {
+ cpu_exit(cpu_single_env);
+ cpu_single_env->stop = 1;
+ }
+ return;
+ }
+ do_vm_stop(reason);
+}
+
+#endif
+
+