X-Git-Url: https://repo.jachan.dev/qemu.git/blobdiff_plain/75312e745ad1b672cbabdc3022f6e7c8eff69b00..cfe25e2bcada943984e27ee63918fd75dc4563ac:/cpus.c

diff --git a/cpus.c b/cpus.c
index 97e9ab4c07..e566297bd3 100644
--- a/cpus.c
+++ b/cpus.c
@@ -60,20 +60,23 @@
 
 #endif /* CONFIG_LINUX */
 
-static CPUArchState *next_cpu;
+static CPUState *next_cpu;
 
-static bool cpu_thread_is_idle(CPUArchState *env)
+bool cpu_is_stopped(CPUState *cpu)
 {
-    CPUState *cpu = ENV_GET_CPU(env);
+    return cpu->stopped || !runstate_is_running();
+}
 
+static bool cpu_thread_is_idle(CPUState *cpu)
+{
     if (cpu->stop || cpu->queued_work_first) {
         return false;
     }
-    if (cpu->stopped || !runstate_is_running()) {
+    if (cpu_is_stopped(cpu)) {
         return true;
     }
     if (!cpu->halted || qemu_cpu_has_work(cpu) ||
-        kvm_async_interrupts_enabled()) {
+        kvm_halt_in_kernel()) {
         return false;
     }
     return true;
@@ -81,10 +84,10 @@ static bool cpu_thread_is_idle(CPUArchState *env)
 
 static bool all_cpu_threads_idle(void)
 {
-    CPUArchState *env;
+    CPUState *cpu;
 
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
-        if (!cpu_thread_is_idle(env)) {
+    CPU_FOREACH(cpu) {
+        if (!cpu_thread_is_idle(cpu)) {
             return false;
         }
     }
@@ -114,16 +117,17 @@ typedef struct TimersState {
     int64_t dummy;
 } TimersState;
 
-TimersState timers_state;
+static TimersState timers_state;
 
 /* Return the virtual CPU time, based on the instruction counter.  */
 int64_t cpu_get_icount(void)
 {
     int64_t icount;
-    CPUArchState *env = cpu_single_env;
+    CPUState *cpu = current_cpu;
 
     icount = qemu_icount;
-    if (env) {
+    if (cpu) {
+        CPUArchState *env = cpu->env_ptr;
         if (!can_do_io(env)) {
             fprintf(stderr, "Bad clock read\n");
         }
@@ -203,7 +207,7 @@ static void icount_adjust(void)
         return;
     }
     cur_time = cpu_get_clock();
-    cur_icount = qemu_get_clock_ns(vm_clock);
+    cur_icount = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
     delta = cur_icount - cur_time;
     /* FIXME: This is a very crude algorithm, somewhat prone to oscillation.  */
     if (delta > 0
@@ -224,15 +228,16 @@ static void icount_adjust(void)
 
 static void icount_adjust_rt(void *opaque)
 {
-    qemu_mod_timer(icount_rt_timer,
-                   qemu_get_clock_ms(rt_clock) + 1000);
+    timer_mod(icount_rt_timer,
+                   qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000);
     icount_adjust();
 }
 
 static void icount_adjust_vm(void *opaque)
 {
-    qemu_mod_timer(icount_vm_timer,
-                   qemu_get_clock_ns(vm_clock) + get_ticks_per_sec() / 10);
+    timer_mod(icount_vm_timer,
+                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
+                   get_ticks_per_sec() / 10);
     icount_adjust();
 }
 
@@ -248,22 +253,22 @@ static void icount_warp_rt(void *opaque)
     }
 
     if (runstate_is_running()) {
-        int64_t clock = qemu_get_clock_ns(rt_clock);
+        int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
         int64_t warp_delta = clock - vm_clock_warp_start;
         if (use_icount == 1) {
             qemu_icount_bias += warp_delta;
         } else {
             /*
-             * In adaptive mode, do not let the vm_clock run too
+             * In adaptive mode, do not let QEMU_CLOCK_VIRTUAL run too
              * far ahead of real time.
              */
             int64_t cur_time = cpu_get_clock();
-            int64_t cur_icount = qemu_get_clock_ns(vm_clock);
+            int64_t cur_icount = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
             int64_t delta = cur_time - cur_icount;
             qemu_icount_bias += MIN(warp_delta, delta);
         }
-        if (qemu_clock_expired(vm_clock)) {
-            qemu_notify_event();
+        if (qemu_clock_expired(QEMU_CLOCK_VIRTUAL)) {
+            qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
         }
     }
     vm_clock_warp_start = -1;
@@ -271,19 +276,19 @@ static void icount_warp_rt(void *opaque)
 
 void qtest_clock_warp(int64_t dest)
 {
-    int64_t clock = qemu_get_clock_ns(vm_clock);
+    int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
     assert(qtest_enabled());
     while (clock < dest) {
-        int64_t deadline = qemu_clock_deadline(vm_clock);
+        int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
         int64_t warp = MIN(dest - clock, deadline);
         qemu_icount_bias += warp;
-        qemu_run_timers(vm_clock);
-        clock = qemu_get_clock_ns(vm_clock);
+        qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
+        clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
     }
-    qemu_notify_event();
+    qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
 }
 
-void qemu_clock_warp(QEMUClock *clock)
+void qemu_clock_warp(QEMUClockType type)
 {
     int64_t deadline;
 
@@ -292,20 +297,20 @@ void qemu_clock_warp(QEMUClock *clock)
      * applicable to other clocks.  But a clock argument removes the
      * need for if statements all over the place.
      */
-    if (clock != vm_clock || !use_icount) {
+    if (type != QEMU_CLOCK_VIRTUAL || !use_icount) {
         return;
     }
 
     /*
-     * If the CPUs have been sleeping, advance the vm_clock timer now.  This
-     * ensures that the deadline for the timer is computed correctly below.
+     * If the CPUs have been sleeping, advance QEMU_CLOCK_VIRTUAL timer now.
+     * This ensures that the deadline for the timer is computed correctly below.
      * This also makes sure that the insn counter is synchronized before the
      * CPU starts running, in case the CPU is woken by an event other than
-     * the earliest vm_clock timer.
+     * the earliest QEMU_CLOCK_VIRTUAL timer.
      */
     icount_warp_rt(NULL);
-    if (!all_cpu_threads_idle() || !qemu_clock_has_timers(vm_clock)) {
-        qemu_del_timer(icount_warp_timer);
+    if (!all_cpu_threads_idle() || !qemu_clock_has_timers(QEMU_CLOCK_VIRTUAL)) {
+        timer_del(icount_warp_timer);
         return;
     }
 
@@ -314,28 +319,40 @@ void qemu_clock_warp(QEMUClock *clock)
 	return;
     }
 
-    vm_clock_warp_start = qemu_get_clock_ns(rt_clock);
-    deadline = qemu_clock_deadline(vm_clock);
+    vm_clock_warp_start = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+    /* We want to use the earliest deadline from ALL vm_clocks */
+    deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
+
+    /* Maintain prior (possibly buggy) behaviour where if no deadline
+     * was set (as there is no QEMU_CLOCK_VIRTUAL timer) or it is more than
+     * INT32_MAX nanoseconds ahead, we still use INT32_MAX
+     * nanoseconds.
+     */
+    if ((deadline < 0) || (deadline > INT32_MAX)) {
+        deadline = INT32_MAX;
+    }
+
     if (deadline > 0) {
         /*
-         * Ensure the vm_clock proceeds even when the virtual CPU goes to
+         * Ensure QEMU_CLOCK_VIRTUAL proceeds even when the virtual CPU goes to
          * sleep.  Otherwise, the CPU might be waiting for a future timer
          * interrupt to wake it up, but the interrupt never comes because
          * the vCPU isn't running any insns and thus doesn't advance the
-         * vm_clock.
+         * QEMU_CLOCK_VIRTUAL.
          *
          * An extreme solution for this problem would be to never let VCPUs
-         * sleep in icount mode if there is a pending vm_clock timer; rather
-         * time could just advance to the next vm_clock event.  Instead, we
-         * do stop VCPUs and only advance vm_clock after some "real" time,
-         * (related to the time left until the next event) has passed.  This
-         * rt_clock timer will do this.  This avoids that the warps are too
-         * visible externally---for example, you will not be sending network
-         * packets continuously instead of every 100ms.
+         * sleep in icount mode if there is a pending QEMU_CLOCK_VIRTUAL
+         * timer; rather time could just advance to the next QEMU_CLOCK_VIRTUAL
+         * event.  Instead, we do stop VCPUs and only advance QEMU_CLOCK_VIRTUAL
+         * after some e"real" time, (related to the time left until the next
+         * event) has passed. The QEMU_CLOCK_REALTIME timer will do this.
+         * This avoids that the warps are visible externally; for example,
+         * you will not be sending network packets continuously instead of
+         * every 100ms.
          */
-        qemu_mod_timer(icount_warp_timer, vm_clock_warp_start + deadline);
-    } else {
-        qemu_notify_event();
+        timer_mod(icount_warp_timer, vm_clock_warp_start + deadline);
+    } else if (deadline == 0) {
+        qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
     }
 }
 
@@ -359,7 +376,8 @@ void configure_icount(const char *option)
         return;
     }
 
-    icount_warp_timer = qemu_new_timer_ns(rt_clock, icount_warp_rt, NULL);
+    icount_warp_timer = timer_new_ns(QEMU_CLOCK_REALTIME,
+                                          icount_warp_rt, NULL);
     if (strcmp(option, "auto") != 0) {
         icount_time_shift = strtol(option, NULL, 0);
         use_icount = 1;
@@ -377,29 +395,30 @@ void configure_icount(const char *option)
        the virtual time trigger catches emulated time passing too fast.
        Realtime triggers occur even when idle, so use them less frequently
        than VM triggers.  */
-    icount_rt_timer = qemu_new_timer_ms(rt_clock, icount_adjust_rt, NULL);
-    qemu_mod_timer(icount_rt_timer,
-                   qemu_get_clock_ms(rt_clock) + 1000);
-    icount_vm_timer = qemu_new_timer_ns(vm_clock, icount_adjust_vm, NULL);
-    qemu_mod_timer(icount_vm_timer,
-                   qemu_get_clock_ns(vm_clock) + get_ticks_per_sec() / 10);
+    icount_rt_timer = timer_new_ms(QEMU_CLOCK_REALTIME,
+                                        icount_adjust_rt, NULL);
+    timer_mod(icount_rt_timer,
+                   qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + 1000);
+    icount_vm_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
+                                        icount_adjust_vm, NULL);
+    timer_mod(icount_vm_timer,
+                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
+                   get_ticks_per_sec() / 10);
 }
 
 /***********************************************************/
 void hw_error(const char *fmt, ...)
 {
     va_list ap;
-    CPUArchState *env;
     CPUState *cpu;
 
     va_start(ap, fmt);
     fprintf(stderr, "qemu: hardware error: ");
     vfprintf(stderr, fmt, ap);
     fprintf(stderr, "\n");
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
-        cpu = ENV_GET_CPU(env);
+    CPU_FOREACH(cpu) {
         fprintf(stderr, "CPU #%d:\n", cpu->cpu_index);
-        cpu_dump_state(env, stderr, fprintf, CPU_DUMP_FPU);
+        cpu_dump_state(cpu, stderr, fprintf, CPU_DUMP_FPU);
     }
     va_end(ap);
     abort();
@@ -407,47 +426,47 @@ void hw_error(const char *fmt, ...)
 
 void cpu_synchronize_all_states(void)
 {
-    CPUArchState *cpu;
+    CPUState *cpu;
 
-    for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
+    CPU_FOREACH(cpu) {
         cpu_synchronize_state(cpu);
     }
 }
 
 void cpu_synchronize_all_post_reset(void)
 {
-    CPUArchState *cpu;
+    CPUState *cpu;
 
-    for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
+    CPU_FOREACH(cpu) {
         cpu_synchronize_post_reset(cpu);
     }
 }
 
 void cpu_synchronize_all_post_init(void)
 {
-    CPUArchState *cpu;
+    CPUState *cpu;
 
-    for (cpu = first_cpu; cpu; cpu = cpu->next_cpu) {
+    CPU_FOREACH(cpu) {
         cpu_synchronize_post_init(cpu);
     }
 }
 
-bool cpu_is_stopped(CPUState *cpu)
+static int do_vm_stop(RunState state)
 {
-    return !runstate_is_running() || cpu->stopped;
-}
+    int ret = 0;
 
-static void do_vm_stop(RunState state)
-{
     if (runstate_is_running()) {
         cpu_disable_ticks();
         pause_all_vcpus();
         runstate_set(state);
         vm_state_notify(0, state);
-        bdrv_drain_all();
-        bdrv_flush_all();
         monitor_protocol_event(QEVENT_STOP, NULL);
     }
+
+    bdrv_drain_all();
+    ret = bdrv_flush_all();
+
+    return ret;
 }
 
 static bool cpu_can_run(CPUState *cpu)
@@ -455,25 +474,23 @@ static bool cpu_can_run(CPUState *cpu)
     if (cpu->stop) {
         return false;
     }
-    if (cpu->stopped || !runstate_is_running()) {
+    if (cpu_is_stopped(cpu)) {
         return false;
     }
     return true;
 }
 
-static void cpu_handle_guest_debug(CPUArchState *env)
+static void cpu_handle_guest_debug(CPUState *cpu)
 {
-    CPUState *cpu = ENV_GET_CPU(env);
-
-    gdb_set_stop_cpu(env);
+    gdb_set_stop_cpu(cpu);
     qemu_system_debug_request();
     cpu->stopped = true;
 }
 
 static void cpu_signal(int sig)
 {
-    if (cpu_single_env) {
-        cpu_exit(cpu_single_env);
+    if (current_cpu) {
+        cpu_exit(current_cpu);
     }
     exit_request = 1;
 }
@@ -570,7 +587,7 @@ static void dummy_signal(int sig)
 {
 }
 
-static void qemu_kvm_init_cpu_signals(CPUArchState *env)
+static void qemu_kvm_init_cpu_signals(CPUState *cpu)
 {
     int r;
     sigset_t set;
@@ -583,7 +600,7 @@ static void qemu_kvm_init_cpu_signals(CPUArchState *env)
     pthread_sigmask(SIG_BLOCK, NULL, &set);
     sigdelset(&set, SIG_IPI);
     sigdelset(&set, SIGBUS);
-    r = kvm_set_signal_mask(env, &set);
+    r = kvm_set_signal_mask(cpu, &set);
     if (r) {
         fprintf(stderr, "kvm_set_signal_mask: %s\n", strerror(-r));
         exit(1);
@@ -605,7 +622,7 @@ static void qemu_tcg_init_cpu_signals(void)
 }
 
 #else /* _WIN32 */
-static void qemu_kvm_init_cpu_signals(CPUArchState *env)
+static void qemu_kvm_init_cpu_signals(CPUState *cpu)
 {
     abort();
 }
@@ -653,6 +670,7 @@ void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
 
     wi.func = func;
     wi.data = data;
+    wi.free = false;
     if (cpu->queued_work_first == NULL) {
         cpu->queued_work_first = &wi;
     } else {
@@ -664,13 +682,38 @@ void run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
 
     qemu_cpu_kick(cpu);
     while (!wi.done) {
-        CPUArchState *self_env = cpu_single_env;
+        CPUState *self_cpu = current_cpu;
 
         qemu_cond_wait(&qemu_work_cond, &qemu_global_mutex);
-        cpu_single_env = self_env;
+        current_cpu = self_cpu;
     }
 }
 
+void async_run_on_cpu(CPUState *cpu, void (*func)(void *data), void *data)
+{
+    struct qemu_work_item *wi;
+
+    if (qemu_cpu_is_self(cpu)) {
+        func(data);
+        return;
+    }
+
+    wi = g_malloc0(sizeof(struct qemu_work_item));
+    wi->func = func;
+    wi->data = data;
+    wi->free = true;
+    if (cpu->queued_work_first == NULL) {
+        cpu->queued_work_first = wi;
+    } else {
+        cpu->queued_work_last->next = wi;
+    }
+    cpu->queued_work_last = wi;
+    wi->next = NULL;
+    wi->done = false;
+
+    qemu_cpu_kick(cpu);
+}
+
 static void flush_queued_work(CPUState *cpu)
 {
     struct qemu_work_item *wi;
@@ -683,6 +726,9 @@ static void flush_queued_work(CPUState *cpu)
         cpu->queued_work_first = wi->next;
         wi->func(wi->data);
         wi->done = true;
+        if (wi->free) {
+            g_free(wi);
+        }
     }
     cpu->queued_work_last = NULL;
     qemu_cond_broadcast(&qemu_work_cond);
@@ -701,12 +747,12 @@ static void qemu_wait_io_event_common(CPUState *cpu)
 
 static void qemu_tcg_wait_io_event(void)
 {
-    CPUArchState *env;
+    CPUState *cpu;
 
     while (all_cpu_threads_idle()) {
        /* Start accounting real time to the virtual clock if the CPUs
           are idle.  */
-        qemu_clock_warp(vm_clock);
+        qemu_clock_warp(QEMU_CLOCK_VIRTUAL);
         qemu_cond_wait(tcg_halt_cond, &qemu_global_mutex);
     }
 
@@ -714,16 +760,14 @@ static void qemu_tcg_wait_io_event(void)
         qemu_cond_wait(&qemu_io_proceeded_cond, &qemu_global_mutex);
     }
 
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
-        qemu_wait_io_event_common(ENV_GET_CPU(env));
+    CPU_FOREACH(cpu) {
+        qemu_wait_io_event_common(cpu);
     }
 }
 
-static void qemu_kvm_wait_io_event(CPUArchState *env)
+static void qemu_kvm_wait_io_event(CPUState *cpu)
 {
-    CPUState *cpu = ENV_GET_CPU(env);
-
-    while (cpu_thread_is_idle(env)) {
+    while (cpu_thread_is_idle(cpu)) {
         qemu_cond_wait(cpu->halt_cond, &qemu_global_mutex);
     }
 
@@ -733,14 +777,13 @@ static void qemu_kvm_wait_io_event(CPUArchState *env)
 
 static void *qemu_kvm_cpu_thread_fn(void *arg)
 {
-    CPUArchState *env = arg;
-    CPUState *cpu = ENV_GET_CPU(env);
+    CPUState *cpu = arg;
     int r;
 
     qemu_mutex_lock(&qemu_global_mutex);
     qemu_thread_get_self(cpu->thread);
     cpu->thread_id = qemu_get_thread_id();
-    cpu_single_env = env;
+    current_cpu = cpu;
 
     r = kvm_init_vcpu(cpu);
     if (r < 0) {
@@ -748,7 +791,7 @@ static void *qemu_kvm_cpu_thread_fn(void *arg)
         exit(1);
     }
 
-    qemu_kvm_init_cpu_signals(env);
+    qemu_kvm_init_cpu_signals(cpu);
 
     /* signal CPU creation */
     cpu->created = true;
@@ -756,12 +799,12 @@ static void *qemu_kvm_cpu_thread_fn(void *arg)
 
     while (1) {
         if (cpu_can_run(cpu)) {
-            r = kvm_cpu_exec(env);
+            r = kvm_cpu_exec(cpu);
             if (r == EXCP_DEBUG) {
-                cpu_handle_guest_debug(env);
+                cpu_handle_guest_debug(cpu);
             }
         }
-        qemu_kvm_wait_io_event(env);
+        qemu_kvm_wait_io_event(cpu);
     }
 
     return NULL;
@@ -773,8 +816,7 @@ static void *qemu_dummy_cpu_thread_fn(void *arg)
     fprintf(stderr, "qtest is not supported under Windows\n");
     exit(1);
 #else
-    CPUArchState *env = arg;
-    CPUState *cpu = ENV_GET_CPU(env);
+    CPUState *cpu = arg;
     sigset_t waitset;
     int r;
 
@@ -789,9 +831,9 @@ static void *qemu_dummy_cpu_thread_fn(void *arg)
     cpu->created = true;
     qemu_cond_signal(&qemu_cpu_cond);
 
-    cpu_single_env = env;
+    current_cpu = cpu;
     while (1) {
-        cpu_single_env = NULL;
+        current_cpu = NULL;
         qemu_mutex_unlock_iothread();
         do {
             int sig;
@@ -802,7 +844,7 @@ static void *qemu_dummy_cpu_thread_fn(void *arg)
             exit(1);
         }
         qemu_mutex_lock_iothread();
-        cpu_single_env = env;
+        current_cpu = cpu;
         qemu_wait_io_event_common(cpu);
     }
 
@@ -815,34 +857,36 @@ static void tcg_exec_all(void);
 static void *qemu_tcg_cpu_thread_fn(void *arg)
 {
     CPUState *cpu = arg;
-    CPUArchState *env;
 
     qemu_tcg_init_cpu_signals();
     qemu_thread_get_self(cpu->thread);
 
-    /* signal CPU creation */
     qemu_mutex_lock(&qemu_global_mutex);
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
-        cpu = ENV_GET_CPU(env);
+    CPU_FOREACH(cpu) {
         cpu->thread_id = qemu_get_thread_id();
         cpu->created = true;
     }
     qemu_cond_signal(&qemu_cpu_cond);
 
     /* wait for initial kick-off after machine start */
-    while (ENV_GET_CPU(first_cpu)->stopped) {
+    while (QTAILQ_FIRST(&cpus)->stopped) {
         qemu_cond_wait(tcg_halt_cond, &qemu_global_mutex);
 
         /* process any pending work */
-        for (env = first_cpu; env != NULL; env = env->next_cpu) {
-            qemu_wait_io_event_common(ENV_GET_CPU(env));
+        CPU_FOREACH(cpu) {
+            qemu_wait_io_event_common(cpu);
         }
     }
 
     while (1) {
         tcg_exec_all();
-        if (use_icount && qemu_clock_deadline(vm_clock) <= 0) {
-            qemu_notify_event();
+
+        if (use_icount) {
+            int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
+
+            if (deadline == 0) {
+                qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+            }
         }
         qemu_tcg_wait_io_event();
     }
@@ -865,7 +909,7 @@ static void qemu_cpu_kick_thread(CPUState *cpu)
         CONTEXT tcgContext;
 
         if (SuspendThread(cpu->hThread) == (DWORD)-1) {
-            fprintf(stderr, "qemu:%s: GetLastError:%d\n", __func__,
+            fprintf(stderr, "qemu:%s: GetLastError:%lu\n", __func__,
                     GetLastError());
             exit(1);
         }
@@ -881,7 +925,7 @@ static void qemu_cpu_kick_thread(CPUState *cpu)
         cpu_signal(0);
 
         if (ResumeThread(cpu->hThread) == (DWORD)-1) {
-            fprintf(stderr, "qemu:%s: GetLastError:%d\n", __func__,
+            fprintf(stderr, "qemu:%s: GetLastError:%lu\n", __func__,
                     GetLastError());
             exit(1);
         }
@@ -901,12 +945,11 @@ void qemu_cpu_kick(CPUState *cpu)
 void qemu_cpu_kick_self(void)
 {
 #ifndef _WIN32
-    assert(cpu_single_env);
-    CPUState *cpu_single_cpu = ENV_GET_CPU(cpu_single_env);
+    assert(current_cpu);
 
-    if (!cpu_single_cpu->thread_kicked) {
-        qemu_cpu_kick_thread(cpu_single_cpu);
-        cpu_single_cpu->thread_kicked = true;
+    if (!current_cpu->thread_kicked) {
+        qemu_cpu_kick_thread(current_cpu);
+        current_cpu->thread_kicked = true;
     }
 #else
     abort();
@@ -920,7 +963,7 @@ bool qemu_cpu_is_self(CPUState *cpu)
 
 static bool qemu_in_vcpu_thread(void)
 {
-    return cpu_single_env && qemu_cpu_is_self(ENV_GET_CPU(cpu_single_env));
+    return current_cpu && qemu_cpu_is_self(current_cpu);
 }
 
 void qemu_mutex_lock_iothread(void)
@@ -930,7 +973,7 @@ void qemu_mutex_lock_iothread(void)
     } else {
         iothread_requesting_mutex = true;
         if (qemu_mutex_trylock(&qemu_global_mutex)) {
-            qemu_cpu_kick_thread(ENV_GET_CPU(first_cpu));
+            qemu_cpu_kick_thread(first_cpu);
             qemu_mutex_lock(&qemu_global_mutex);
         }
         iothread_requesting_mutex = false;
@@ -945,14 +988,12 @@ void qemu_mutex_unlock_iothread(void)
 
 static int all_vcpus_paused(void)
 {
-    CPUArchState *penv = first_cpu;
+    CPUState *cpu;
 
-    while (penv) {
-        CPUState *pcpu = ENV_GET_CPU(penv);
-        if (!pcpu->stopped) {
+    CPU_FOREACH(cpu) {
+        if (!cpu->stopped) {
             return 0;
         }
-        penv = penv->next_cpu;
     }
 
     return 1;
@@ -960,24 +1001,20 @@ static int all_vcpus_paused(void)
 
 void pause_all_vcpus(void)
 {
-    CPUArchState *penv = first_cpu;
+    CPUState *cpu;
 
-    qemu_clock_enable(vm_clock, false);
-    while (penv) {
-        CPUState *pcpu = ENV_GET_CPU(penv);
-        pcpu->stop = true;
-        qemu_cpu_kick(pcpu);
-        penv = penv->next_cpu;
+    qemu_clock_enable(QEMU_CLOCK_VIRTUAL, false);
+    CPU_FOREACH(cpu) {
+        cpu->stop = true;
+        qemu_cpu_kick(cpu);
     }
 
     if (qemu_in_vcpu_thread()) {
         cpu_stop_current();
         if (!kvm_enabled()) {
-            while (penv) {
-                CPUState *pcpu = ENV_GET_CPU(penv);
-                pcpu->stop = 0;
-                pcpu->stopped = true;
-                penv = penv->next_cpu;
+            CPU_FOREACH(cpu) {
+                cpu->stop = false;
+                cpu->stopped = true;
             }
             return;
         }
@@ -985,25 +1022,26 @@ void pause_all_vcpus(void)
 
     while (!all_vcpus_paused()) {
         qemu_cond_wait(&qemu_pause_cond, &qemu_global_mutex);
-        penv = first_cpu;
-        while (penv) {
-            qemu_cpu_kick(ENV_GET_CPU(penv));
-            penv = penv->next_cpu;
+        CPU_FOREACH(cpu) {
+            qemu_cpu_kick(cpu);
         }
     }
 }
 
+void cpu_resume(CPUState *cpu)
+{
+    cpu->stop = false;
+    cpu->stopped = false;
+    qemu_cpu_kick(cpu);
+}
+
 void resume_all_vcpus(void)
 {
-    CPUArchState *penv = first_cpu;
+    CPUState *cpu;
 
-    qemu_clock_enable(vm_clock, true);
-    while (penv) {
-        CPUState *pcpu = ENV_GET_CPU(penv);
-        pcpu->stop = false;
-        pcpu->stopped = false;
-        qemu_cpu_kick(pcpu);
-        penv = penv->next_cpu;
+    qemu_clock_enable(QEMU_CLOCK_VIRTUAL, true);
+    CPU_FOREACH(cpu) {
+        cpu_resume(cpu);
     }
 }
 
@@ -1030,63 +1068,55 @@ static void qemu_tcg_init_vcpu(CPUState *cpu)
     }
 }
 
-static void qemu_kvm_start_vcpu(CPUArchState *env)
+static void qemu_kvm_start_vcpu(CPUState *cpu)
 {
-    CPUState *cpu = ENV_GET_CPU(env);
-
     cpu->thread = g_malloc0(sizeof(QemuThread));
     cpu->halt_cond = g_malloc0(sizeof(QemuCond));
     qemu_cond_init(cpu->halt_cond);
-    qemu_thread_create(cpu->thread, qemu_kvm_cpu_thread_fn, env,
+    qemu_thread_create(cpu->thread, qemu_kvm_cpu_thread_fn, cpu,
                        QEMU_THREAD_JOINABLE);
     while (!cpu->created) {
         qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
     }
 }
 
-static void qemu_dummy_start_vcpu(CPUArchState *env)
+static void qemu_dummy_start_vcpu(CPUState *cpu)
 {
-    CPUState *cpu = ENV_GET_CPU(env);
-
     cpu->thread = g_malloc0(sizeof(QemuThread));
     cpu->halt_cond = g_malloc0(sizeof(QemuCond));
     qemu_cond_init(cpu->halt_cond);
-    qemu_thread_create(cpu->thread, qemu_dummy_cpu_thread_fn, env,
+    qemu_thread_create(cpu->thread, qemu_dummy_cpu_thread_fn, cpu,
                        QEMU_THREAD_JOINABLE);
     while (!cpu->created) {
         qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
     }
 }
 
-void qemu_init_vcpu(void *_env)
+void qemu_init_vcpu(CPUState *cpu)
 {
-    CPUArchState *env = _env;
-    CPUState *cpu = ENV_GET_CPU(env);
-
     cpu->nr_cores = smp_cores;
     cpu->nr_threads = smp_threads;
     cpu->stopped = true;
     if (kvm_enabled()) {
-        qemu_kvm_start_vcpu(env);
+        qemu_kvm_start_vcpu(cpu);
     } else if (tcg_enabled()) {
         qemu_tcg_init_vcpu(cpu);
     } else {
-        qemu_dummy_start_vcpu(env);
+        qemu_dummy_start_vcpu(cpu);
     }
 }
 
 void cpu_stop_current(void)
 {
-    if (cpu_single_env) {
-        CPUState *cpu_single_cpu = ENV_GET_CPU(cpu_single_env);
-        cpu_single_cpu->stop = false;
-        cpu_single_cpu->stopped = true;
-        cpu_exit(cpu_single_env);
+    if (current_cpu) {
+        current_cpu->stop = false;
+        current_cpu->stopped = true;
+        cpu_exit(current_cpu);
         qemu_cond_signal(&qemu_pause_cond);
     }
 }
 
-void vm_stop(RunState state)
+int vm_stop(RunState state)
 {
     if (qemu_in_vcpu_thread()) {
         qemu_system_vmstop_request(state);
@@ -1095,19 +1125,23 @@ void vm_stop(RunState state)
          * vm_stop() has been requested.
          */
         cpu_stop_current();
-        return;
+        return 0;
     }
-    do_vm_stop(state);
+
+    return do_vm_stop(state);
 }
 
 /* does a state transition even if the VM is already stopped,
    current state is forgotten forever */
-void vm_stop_force_state(RunState state)
+int vm_stop_force_state(RunState state)
 {
     if (runstate_is_running()) {
-        vm_stop(state);
+        return vm_stop(state);
     } else {
         runstate_set(state);
+        /* Make sure to return an error if the flush in a previous vm_stop()
+         * failed. */
+        return bdrv_flush_all();
     }
 }
 
@@ -1123,11 +1157,23 @@ static int tcg_cpu_exec(CPUArchState *env)
 #endif
     if (use_icount) {
         int64_t count;
+        int64_t deadline;
         int decr;
         qemu_icount -= (env->icount_decr.u16.low + env->icount_extra);
         env->icount_decr.u16.low = 0;
         env->icount_extra = 0;
-        count = qemu_icount_round(qemu_clock_deadline(vm_clock));
+        deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
+
+        /* Maintain prior (possibly buggy) behaviour where if no deadline
+         * was set (as there is no QEMU_CLOCK_VIRTUAL timer) or it is more than
+         * INT32_MAX nanoseconds ahead, we still use INT32_MAX
+         * nanoseconds.
+         */
+        if ((deadline < 0) || (deadline > INT32_MAX)) {
+            deadline = INT32_MAX;
+        }
+
+        count = qemu_icount_round(deadline);
         qemu_icount += count;
         decr = (count > 0xffff) ? 0xffff : count;
         count -= decr;
@@ -1153,23 +1199,23 @@ static void tcg_exec_all(void)
 {
     int r;
 
-    /* Account partial waits to the vm_clock.  */
-    qemu_clock_warp(vm_clock);
+    /* Account partial waits to QEMU_CLOCK_VIRTUAL.  */
+    qemu_clock_warp(QEMU_CLOCK_VIRTUAL);
 
     if (next_cpu == NULL) {
         next_cpu = first_cpu;
     }
-    for (; next_cpu != NULL && !exit_request; next_cpu = next_cpu->next_cpu) {
-        CPUArchState *env = next_cpu;
-        CPUState *cpu = ENV_GET_CPU(env);
+    for (; next_cpu != NULL && !exit_request; next_cpu = CPU_NEXT(next_cpu)) {
+        CPUState *cpu = next_cpu;
+        CPUArchState *env = cpu->env_ptr;
 
-        qemu_clock_enable(vm_clock,
-                          (env->singlestep_enabled & SSTEP_NOTIMER) == 0);
+        qemu_clock_enable(QEMU_CLOCK_VIRTUAL,
+                          (cpu->singlestep_enabled & SSTEP_NOTIMER) == 0);
 
         if (cpu_can_run(cpu)) {
             r = tcg_cpu_exec(env);
             if (r == EXCP_DEBUG) {
-                cpu_handle_guest_debug(env);
+                cpu_handle_guest_debug(cpu);
                 break;
             }
         } else if (cpu->stop || cpu->stopped) {
@@ -1181,12 +1227,10 @@ static void tcg_exec_all(void)
 
 void set_numa_modes(void)
 {
-    CPUArchState *env;
     CPUState *cpu;
     int i;
 
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
-        cpu = ENV_GET_CPU(env);
+    CPU_FOREACH(cpu) {
         for (i = 0; i < nb_numa_nodes; i++) {
             if (test_bit(cpu->cpu_index, node_cpumask[i])) {
                 cpu->numa_node = i;
@@ -1206,18 +1250,30 @@ void list_cpus(FILE *f, fprintf_function cpu_fprintf, const char *optarg)
 CpuInfoList *qmp_query_cpus(Error **errp)
 {
     CpuInfoList *head = NULL, *cur_item = NULL;
-    CPUArchState *env;
+    CPUState *cpu;
 
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
-        CPUState *cpu = ENV_GET_CPU(env);
+    CPU_FOREACH(cpu) {
         CpuInfoList *info;
+#if defined(TARGET_I386)
+        X86CPU *x86_cpu = X86_CPU(cpu);
+        CPUX86State *env = &x86_cpu->env;
+#elif defined(TARGET_PPC)
+        PowerPCCPU *ppc_cpu = POWERPC_CPU(cpu);
+        CPUPPCState *env = &ppc_cpu->env;
+#elif defined(TARGET_SPARC)
+        SPARCCPU *sparc_cpu = SPARC_CPU(cpu);
+        CPUSPARCState *env = &sparc_cpu->env;
+#elif defined(TARGET_MIPS)
+        MIPSCPU *mips_cpu = MIPS_CPU(cpu);
+        CPUMIPSState *env = &mips_cpu->env;
+#endif
 
-        cpu_synchronize_state(env);
+        cpu_synchronize_state(cpu);
 
         info = g_malloc0(sizeof(*info));
         info->value = g_malloc0(sizeof(*info->value));
         info->value->CPU = cpu->cpu_index;
-        info->value->current = (env == first_cpu);
+        info->value->current = (cpu == first_cpu);
         info->value->halted = cpu->halted;
         info->value->thread_id = cpu->thread_id;
 #if defined(TARGET_I386)
@@ -1253,7 +1309,6 @@ void qmp_memsave(int64_t addr, int64_t size, const char *filename,
 {
     FILE *f;
     uint32_t l;
-    CPUArchState *env;
     CPUState *cpu;
     uint8_t buf[1024];
 
@@ -1267,11 +1322,10 @@ void qmp_memsave(int64_t addr, int64_t size, const char *filename,
                   "a CPU number");
         return;
     }
-    env = cpu->env_ptr;
 
     f = fopen(filename, "wb");
     if (!f) {
-        error_set(errp, QERR_OPEN_FILE_FAILED, filename);
+        error_setg_file_open(errp, errno, filename);
         return;
     }
 
@@ -1279,7 +1333,7 @@ void qmp_memsave(int64_t addr, int64_t size, const char *filename,
         l = sizeof(buf);
         if (l > size)
             l = size;
-        cpu_memory_rw_debug(env, addr, buf, l, 0);
+        cpu_memory_rw_debug(cpu, addr, buf, l, 0);
         if (fwrite(buf, 1, l, f) != l) {
             error_set(errp, QERR_IO_ERROR);
             goto exit;
@@ -1301,7 +1355,7 @@ void qmp_pmemsave(int64_t addr, int64_t size, const char *filename,
 
     f = fopen(filename, "wb");
     if (!f) {
-        error_set(errp, QERR_OPEN_FILE_FAILED, filename);
+        error_setg_file_open(errp, errno, filename);
         return;
     }
 
@@ -1325,15 +1379,32 @@ exit:
 void qmp_inject_nmi(Error **errp)
 {
 #if defined(TARGET_I386)
-    CPUArchState *env;
+    CPUState *cs;
+
+    CPU_FOREACH(cs) {
+        X86CPU *cpu = X86_CPU(cs);
+        CPUX86State *env = &cpu->env;
 
-    for (env = first_cpu; env != NULL; env = env->next_cpu) {
         if (!env->apic_state) {
-            cpu_interrupt(CPU(x86_env_get_cpu(env)), CPU_INTERRUPT_NMI);
+            cpu_interrupt(cs, CPU_INTERRUPT_NMI);
         } else {
             apic_deliver_nmi(env->apic_state);
         }
     }
+#elif defined(TARGET_S390X)
+    CPUState *cs;
+    S390CPU *cpu;
+
+    CPU_FOREACH(cs) {
+        cpu = S390_CPU(cs);
+        if (cpu->env.cpu_num == monitor_get_cpu_index()) {
+            if (s390_cpu_restart(S390_CPU(cs)) == -1) {
+                error_set(errp, QERR_UNSUPPORTED);
+                return;
+            }
+            break;
+        }
+    }
 #else
     error_set(errp, QERR_UNSUPPORTED);
 #endif