softmmu: move softmmu only files from root

move arch_init, balloon, cpus, ioport, memory, memory_mapping, qtest.

They are all specific to CONFIG_SOFTMMU.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20200629093504.3228-2-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 2317 insertions, 0 deletions

diff --git a/softmmu/cpus.c b/softmmu/cpus.c
new file mode 100644
index 0000000000..d94456ed29
--- /dev/null
+++ b/softmmu/cpus.c
@@ -0,0 +1,2317 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "qemu/config-file.h"
+#include "qemu/cutils.h"
+#include "migration/vmstate.h"
+#include "monitor/monitor.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-misc.h"
+#include "qapi/qapi-events-run-state.h"
+#include "qapi/qmp/qerror.h"
+#include "qemu/error-report.h"
+#include "qemu/qemu-print.h"
+#include "sysemu/tcg.h"
+#include "sysemu/block-backend.h"
+#include "exec/gdbstub.h"
+#include "sysemu/dma.h"
+#include "sysemu/hw_accel.h"
+#include "sysemu/kvm.h"
+#include "sysemu/hax.h"
+#include "sysemu/hvf.h"
+#include "sysemu/whpx.h"
+#include "exec/exec-all.h"
+
+#include "qemu/thread.h"
+#include "qemu/plugin.h"
+#include "sysemu/cpus.h"
+#include "sysemu/qtest.h"
+#include "qemu/main-loop.h"
+#include "qemu/option.h"
+#include "qemu/bitmap.h"
+#include "qemu/seqlock.h"
+#include "qemu/guest-random.h"
+#include "tcg/tcg.h"
+#include "hw/nmi.h"
+#include "sysemu/replay.h"
+#include "sysemu/runstate.h"
+#include "hw/boards.h"
+#include "hw/hw.h"
+
+#ifdef CONFIG_LINUX
+
+#include <sys/prctl.h>
+
+#ifndef PR_MCE_KILL
+#define PR_MCE_KILL 33
+#endif
+
+#ifndef PR_MCE_KILL_SET
+#define PR_MCE_KILL_SET 1
+#endif
+
+#ifndef PR_MCE_KILL_EARLY
+#define PR_MCE_KILL_EARLY 1
+#endif
+
+#endif /* CONFIG_LINUX */
+
+static QemuMutex qemu_global_mutex;
+
+int64_t max_delay;
+int64_t max_advance;
+
+/* vcpu throttling controls */
+static QEMUTimer *throttle_timer;
+static unsigned int throttle_percentage;
+
+#define CPU_THROTTLE_PCT_MIN 1
+#define CPU_THROTTLE_PCT_MAX 99
+#define CPU_THROTTLE_TIMESLICE_NS 10000000
+
+bool cpu_is_stopped(CPUState *cpu)
+{
+    return cpu->stopped || !runstate_is_running();
+}
+
+static inline bool cpu_work_list_empty(CPUState *cpu)
+{
+    bool ret;
+
+    qemu_mutex_lock(&cpu->work_mutex);
+    ret = QSIMPLEQ_EMPTY(&cpu->work_list);
+    qemu_mutex_unlock(&cpu->work_mutex);
+    return ret;
+}
+
+static bool cpu_thread_is_idle(CPUState *cpu)
+{
+    if (cpu->stop || !cpu_work_list_empty(cpu)) {
+        return false;
+    }
+    if (cpu_is_stopped(cpu)) {
+        return true;
+    }
+    if (!cpu->halted || cpu_has_work(cpu) ||
+        kvm_halt_in_kernel()) {
+        return false;
+    }
+    return true;
+}
+
+static bool all_cpu_threads_idle(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        if (!cpu_thread_is_idle(cpu)) {
+            return false;
+        }
+    }
+    return true;
+}
+
+/***********************************************************/
+/* guest cycle counter */
+
+/* Protected by TimersState seqlock */
+
+static bool icount_sleep = true;
+/* Arbitrarily pick 1MIPS as the minimum allowable speed.  */
+#define MAX_ICOUNT_SHIFT 10
+
+typedef struct TimersState {
+    /* Protected by BQL.  */
+    int64_t cpu_ticks_prev;
+    int64_t cpu_ticks_offset;
+
+    /* Protect fields that can be respectively read outside the
+     * BQL, and written from multiple threads.
+     */
+    QemuSeqLock vm_clock_seqlock;
+    QemuSpin vm_clock_lock;
+
+    int16_t cpu_ticks_enabled;
+
+    /* Conversion factor from emulated instructions to virtual clock ticks.  */
+    int16_t icount_time_shift;
+
+    /* Compensate for varying guest execution speed.  */
+    int64_t qemu_icount_bias;
+
+    int64_t vm_clock_warp_start;
+    int64_t cpu_clock_offset;
+
+    /* Only written by TCG thread */
+    int64_t qemu_icount;
+
+    /* for adjusting icount */
+    QEMUTimer *icount_rt_timer;
+    QEMUTimer *icount_vm_timer;
+    QEMUTimer *icount_warp_timer;
+} TimersState;
+
+static TimersState timers_state;
+bool mttcg_enabled;
+
+
+/* The current number of executed instructions is based on what we
+ * originally budgeted minus the current state of the decrementing
+ * icount counters in extra/u16.low.
+ */
+static int64_t cpu_get_icount_executed(CPUState *cpu)
+{
+    return (cpu->icount_budget -
+            (cpu_neg(cpu)->icount_decr.u16.low + cpu->icount_extra));
+}
+
+/*
+ * Update the global shared timer_state.qemu_icount to take into
+ * account executed instructions. This is done by the TCG vCPU
+ * thread so the main-loop can see time has moved forward.
+ */
+static void cpu_update_icount_locked(CPUState *cpu)
+{
+    int64_t executed = cpu_get_icount_executed(cpu);
+    cpu->icount_budget -= executed;
+
+    atomic_set_i64(&timers_state.qemu_icount,
+                   timers_state.qemu_icount + executed);
+}
+
+/*
+ * Update the global shared timer_state.qemu_icount to take into
+ * account executed instructions. This is done by the TCG vCPU
+ * thread so the main-loop can see time has moved forward.
+ */
+void cpu_update_icount(CPUState *cpu)
+{
+    seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+    cpu_update_icount_locked(cpu);
+    seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                         &timers_state.vm_clock_lock);
+}
+
+static int64_t cpu_get_icount_raw_locked(void)
+{
+    CPUState *cpu = current_cpu;
+
+    if (cpu && cpu->running) {
+        if (!cpu->can_do_io) {
+            error_report("Bad icount read");
+            exit(1);
+        }
+        /* Take into account what has run */
+        cpu_update_icount_locked(cpu);
+    }
+    /* The read is protected by the seqlock, but needs atomic64 to avoid UB */
+    return atomic_read_i64(&timers_state.qemu_icount);
+}
+
+static int64_t cpu_get_icount_locked(void)
+{
+    int64_t icount = cpu_get_icount_raw_locked();
+    return atomic_read_i64(&timers_state.qemu_icount_bias) +
+        cpu_icount_to_ns(icount);
+}
+
+int64_t cpu_get_icount_raw(void)
+{
+    int64_t icount;
+    unsigned start;
+
+    do {
+        start = seqlock_read_begin(&timers_state.vm_clock_seqlock);
+        icount = cpu_get_icount_raw_locked();
+    } while (seqlock_read_retry(&timers_state.vm_clock_seqlock, start));
+
+    return icount;
+}
+
+/* Return the virtual CPU time, based on the instruction counter.  */
+int64_t cpu_get_icount(void)
+{
+    int64_t icount;
+    unsigned start;
+
+    do {
+        start = seqlock_read_begin(&timers_state.vm_clock_seqlock);
+        icount = cpu_get_icount_locked();
+    } while (seqlock_read_retry(&timers_state.vm_clock_seqlock, start));
+
+    return icount;
+}
+
+int64_t cpu_icount_to_ns(int64_t icount)
+{
+    return icount << atomic_read(&timers_state.icount_time_shift);
+}
+
+static int64_t cpu_get_ticks_locked(void)
+{
+    int64_t ticks = timers_state.cpu_ticks_offset;
+    if (timers_state.cpu_ticks_enabled) {
+        ticks += cpu_get_host_ticks();
+    }
+
+    if (timers_state.cpu_ticks_prev > ticks) {
+        /* Non increasing ticks may happen if the host uses software suspend.  */
+        timers_state.cpu_ticks_offset += timers_state.cpu_ticks_prev - ticks;
+        ticks = timers_state.cpu_ticks_prev;
+    }
+
+    timers_state.cpu_ticks_prev = ticks;
+    return ticks;
+}
+
+/* return the time elapsed in VM between vm_start and vm_stop.  Unless
+ * icount is active, cpu_get_ticks() uses units of the host CPU cycle
+ * counter.
+ */
+int64_t cpu_get_ticks(void)
+{
+    int64_t ticks;
+
+    if (use_icount) {
+        return cpu_get_icount();
+    }
+
+    qemu_spin_lock(&timers_state.vm_clock_lock);
+    ticks = cpu_get_ticks_locked();
+    qemu_spin_unlock(&timers_state.vm_clock_lock);
+    return ticks;
+}
+
+static int64_t cpu_get_clock_locked(void)
+{
+    int64_t time;
+
+    time = timers_state.cpu_clock_offset;
+    if (timers_state.cpu_ticks_enabled) {
+        time += get_clock();
+    }
+
+    return time;
+}
+
+/* Return the monotonic time elapsed in VM, i.e.,
+ * the time between vm_start and vm_stop
+ */
+int64_t cpu_get_clock(void)
+{
+    int64_t ti;
+    unsigned start;
+
+    do {
+        start = seqlock_read_begin(&timers_state.vm_clock_seqlock);
+        ti = cpu_get_clock_locked();
+    } while (seqlock_read_retry(&timers_state.vm_clock_seqlock, start));
+
+    return ti;
+}
+
+/* enable cpu_get_ticks()
+ * Caller must hold BQL which serves as mutex for vm_clock_seqlock.
+ */
+void cpu_enable_ticks(void)
+{
+    seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+    if (!timers_state.cpu_ticks_enabled) {
+        timers_state.cpu_ticks_offset -= cpu_get_host_ticks();
+        timers_state.cpu_clock_offset -= get_clock();
+        timers_state.cpu_ticks_enabled = 1;
+    }
+    seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+}
+
+/* disable cpu_get_ticks() : the clock is stopped. You must not call
+ * cpu_get_ticks() after that.
+ * Caller must hold BQL which serves as mutex for vm_clock_seqlock.
+ */
+void cpu_disable_ticks(void)
+{
+    seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+    if (timers_state.cpu_ticks_enabled) {
+        timers_state.cpu_ticks_offset += cpu_get_host_ticks();
+        timers_state.cpu_clock_offset = cpu_get_clock_locked();
+        timers_state.cpu_ticks_enabled = 0;
+    }
+    seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                         &timers_state.vm_clock_lock);
+}
+
+/* Correlation between real and virtual time is always going to be
+   fairly approximate, so ignore small variation.
+   When the guest is idle real and virtual time will be aligned in
+   the IO wait loop.  */
+#define ICOUNT_WOBBLE (NANOSECONDS_PER_SECOND / 10)
+
+static void icount_adjust(void)
+{
+    int64_t cur_time;
+    int64_t cur_icount;
+    int64_t delta;
+
+    /* Protected by TimersState mutex.  */
+    static int64_t last_delta;
+
+    /* If the VM is not running, then do nothing.  */
+    if (!runstate_is_running()) {
+        return;
+    }
+
+    seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+    cur_time = REPLAY_CLOCK_LOCKED(REPLAY_CLOCK_VIRTUAL_RT,
+                                   cpu_get_clock_locked());
+    cur_icount = cpu_get_icount_locked();
+
+    delta = cur_icount - cur_time;
+    /* FIXME: This is a very crude algorithm, somewhat prone to oscillation.  */
+    if (delta > 0
+        && last_delta + ICOUNT_WOBBLE < delta * 2
+        && timers_state.icount_time_shift > 0) {
+        /* The guest is getting too far ahead.  Slow time down.  */
+        atomic_set(&timers_state.icount_time_shift,
+                   timers_state.icount_time_shift - 1);
+    }
+    if (delta < 0
+        && last_delta - ICOUNT_WOBBLE > delta * 2
+        && timers_state.icount_time_shift < MAX_ICOUNT_SHIFT) {
+        /* The guest is getting too far behind.  Speed time up.  */
+        atomic_set(&timers_state.icount_time_shift,
+                   timers_state.icount_time_shift + 1);
+    }
+    last_delta = delta;
+    atomic_set_i64(&timers_state.qemu_icount_bias,
+                   cur_icount - (timers_state.qemu_icount
+                                 << timers_state.icount_time_shift));
+    seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                         &timers_state.vm_clock_lock);
+}
+
+static void icount_adjust_rt(void *opaque)
+{
+    timer_mod(timers_state.icount_rt_timer,
+              qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + 1000);
+    icount_adjust();
+}
+
+static void icount_adjust_vm(void *opaque)
+{
+    timer_mod(timers_state.icount_vm_timer,
+                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
+                   NANOSECONDS_PER_SECOND / 10);
+    icount_adjust();
+}
+
+static int64_t qemu_icount_round(int64_t count)
+{
+    int shift = atomic_read(&timers_state.icount_time_shift);
+    return (count + (1 << shift) - 1) >> shift;
+}
+
+static void icount_warp_rt(void)
+{
+    unsigned seq;
+    int64_t warp_start;
+
+    /* The icount_warp_timer is rescheduled soon after vm_clock_warp_start
+     * changes from -1 to another value, so the race here is okay.
+     */
+    do {
+        seq = seqlock_read_begin(&timers_state.vm_clock_seqlock);
+        warp_start = timers_state.vm_clock_warp_start;
+    } while (seqlock_read_retry(&timers_state.vm_clock_seqlock, seq));
+
+    if (warp_start == -1) {
+        return;
+    }
+
+    seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+    if (runstate_is_running()) {
+        int64_t clock = REPLAY_CLOCK_LOCKED(REPLAY_CLOCK_VIRTUAL_RT,
+                                            cpu_get_clock_locked());
+        int64_t warp_delta;
+
+        warp_delta = clock - timers_state.vm_clock_warp_start;
+        if (use_icount == 2) {
+            /*
+             * In adaptive mode, do not let QEMU_CLOCK_VIRTUAL run too
+             * far ahead of real time.
+             */
+            int64_t cur_icount = cpu_get_icount_locked();
+            int64_t delta = clock - cur_icount;
+            warp_delta = MIN(warp_delta, delta);
+        }
+        atomic_set_i64(&timers_state.qemu_icount_bias,
+                       timers_state.qemu_icount_bias + warp_delta);
+    }
+    timers_state.vm_clock_warp_start = -1;
+    seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                       &timers_state.vm_clock_lock);
+
+    if (qemu_clock_expired(QEMU_CLOCK_VIRTUAL)) {
+        qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+    }
+}
+
+static void icount_timer_cb(void *opaque)
+{
+    /* No need for a checkpoint because the timer already synchronizes
+     * with CHECKPOINT_CLOCK_VIRTUAL_RT.
+     */
+    icount_warp_rt();
+}
+
+void qtest_clock_warp(int64_t dest)
+{
+    int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    AioContext *aio_context;
+    assert(qtest_enabled());
+    aio_context = qemu_get_aio_context();
+    while (clock < dest) {
+        int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
+                                                      QEMU_TIMER_ATTR_ALL);
+        int64_t warp = qemu_soonest_timeout(dest - clock, deadline);
+
+        seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                           &timers_state.vm_clock_lock);
+        atomic_set_i64(&timers_state.qemu_icount_bias,
+                       timers_state.qemu_icount_bias + warp);
+        seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                             &timers_state.vm_clock_lock);
+
+        qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
+        timerlist_run_timers(aio_context->tlg.tl[QEMU_CLOCK_VIRTUAL]);
+        clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    }
+    qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+}
+
+void qemu_start_warp_timer(void)
+{
+    int64_t clock;
+    int64_t deadline;
+
+    if (!use_icount) {
+        return;
+    }
+
+    /* Nothing to do if the VM is stopped: QEMU_CLOCK_VIRTUAL timers
+     * do not fire, so computing the deadline does not make sense.
+     */
+    if (!runstate_is_running()) {
+        return;
+    }
+
+    if (replay_mode != REPLAY_MODE_PLAY) {
+        if (!all_cpu_threads_idle()) {
+            return;
+        }
+
+        if (qtest_enabled()) {
+            /* When testing, qtest commands advance icount.  */
+            return;
+        }
+
+        replay_checkpoint(CHECKPOINT_CLOCK_WARP_START);
+    } else {
+        /* warp clock deterministically in record/replay mode */
+        if (!replay_checkpoint(CHECKPOINT_CLOCK_WARP_START)) {
+            /* vCPU is sleeping and warp can't be started.
+               It is probably a race condition: notification sent
+               to vCPU was processed in advance and vCPU went to sleep.
+               Therefore we have to wake it up for doing someting. */
+            if (replay_has_checkpoint()) {
+                qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+            }
+            return;
+        }
+    }
+
+    /* We want to use the earliest deadline from ALL vm_clocks */
+    clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT);
+    deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
+                                          ~QEMU_TIMER_ATTR_EXTERNAL);
+    if (deadline < 0) {
+        static bool notified;
+        if (!icount_sleep && !notified) {
+            warn_report("icount sleep disabled and no active timers");
+            notified = true;
+        }
+        return;
+    }
+
+    if (deadline > 0) {
+        /*
+         * 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
+         * QEMU_CLOCK_VIRTUAL.
+         */
+        if (!icount_sleep) {
+            /*
+             * We never let VCPUs sleep in no sleep icount mode.
+             * If there is a pending QEMU_CLOCK_VIRTUAL timer we just advance
+             * to the next QEMU_CLOCK_VIRTUAL event and notify it.
+             * It is useful when we want a deterministic execution time,
+             * isolated from host latencies.
+             */
+            seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                               &timers_state.vm_clock_lock);
+            atomic_set_i64(&timers_state.qemu_icount_bias,
+                           timers_state.qemu_icount_bias + deadline);
+            seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                                 &timers_state.vm_clock_lock);
+            qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+        } else {
+            /*
+             * We do stop VCPUs and only advance QEMU_CLOCK_VIRTUAL after some
+             * "real" time, (related to the time left until the next event) has
+             * passed. The QEMU_CLOCK_VIRTUAL_RT clock 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.
+             */
+            seqlock_write_lock(&timers_state.vm_clock_seqlock,
+                               &timers_state.vm_clock_lock);
+            if (timers_state.vm_clock_warp_start == -1
+                || timers_state.vm_clock_warp_start > clock) {
+                timers_state.vm_clock_warp_start = clock;
+            }
+            seqlock_write_unlock(&timers_state.vm_clock_seqlock,
+                                 &timers_state.vm_clock_lock);
+            timer_mod_anticipate(timers_state.icount_warp_timer,
+                                 clock + deadline);
+        }
+    } else if (deadline == 0) {
+        qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+    }
+}
+
+static void qemu_account_warp_timer(void)
+{
+    if (!use_icount || !icount_sleep) {
+        return;
+    }
+
+    /* Nothing to do if the VM is stopped: QEMU_CLOCK_VIRTUAL timers
+     * do not fire, so computing the deadline does not make sense.
+     */
+    if (!runstate_is_running()) {
+        return;
+    }
+
+    /* warp clock deterministically in record/replay mode */
+    if (!replay_checkpoint(CHECKPOINT_CLOCK_WARP_ACCOUNT)) {
+        return;
+    }
+
+    timer_del(timers_state.icount_warp_timer);
+    icount_warp_rt();
+}
+
+static bool icount_state_needed(void *opaque)
+{
+    return use_icount;
+}
+
+static bool warp_timer_state_needed(void *opaque)
+{
+    TimersState *s = opaque;
+    return s->icount_warp_timer != NULL;
+}
+
+static bool adjust_timers_state_needed(void *opaque)
+{
+    TimersState *s = opaque;
+    return s->icount_rt_timer != NULL;
+}
+
+static bool shift_state_needed(void *opaque)
+{
+    return use_icount == 2;
+}
+
+/*
+ * Subsection for warp timer migration is optional, because may not be created
+ */
+static const VMStateDescription icount_vmstate_warp_timer = {
+    .name = "timer/icount/warp_timer",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = warp_timer_state_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_INT64(vm_clock_warp_start, TimersState),
+        VMSTATE_TIMER_PTR(icount_warp_timer, TimersState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription icount_vmstate_adjust_timers = {
+    .name = "timer/icount/timers",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = adjust_timers_state_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_TIMER_PTR(icount_rt_timer, TimersState),
+        VMSTATE_TIMER_PTR(icount_vm_timer, TimersState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription icount_vmstate_shift = {
+    .name = "timer/icount/shift",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = shift_state_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_INT16(icount_time_shift, TimersState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+/*
+ * This is a subsection for icount migration.
+ */
+static const VMStateDescription icount_vmstate_timers = {
+    .name = "timer/icount",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = icount_state_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_INT64(qemu_icount_bias, TimersState),
+        VMSTATE_INT64(qemu_icount, TimersState),
+        VMSTATE_END_OF_LIST()
+    },
+    .subsections = (const VMStateDescription*[]) {
+        &icount_vmstate_warp_timer,
+        &icount_vmstate_adjust_timers,
+        &icount_vmstate_shift,
+        NULL
+    }
+};
+
+static const VMStateDescription vmstate_timers = {
+    .name = "timer",
+    .version_id = 2,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_INT64(cpu_ticks_offset, TimersState),
+        VMSTATE_UNUSED(8),
+        VMSTATE_INT64_V(cpu_clock_offset, TimersState, 2),
+        VMSTATE_END_OF_LIST()
+    },
+    .subsections = (const VMStateDescription*[]) {
+        &icount_vmstate_timers,
+        NULL
+    }
+};
+
+static void cpu_throttle_thread(CPUState *cpu, run_on_cpu_data opaque)
+{
+    double pct;
+    double throttle_ratio;
+    int64_t sleeptime_ns, endtime_ns;
+
+    if (!cpu_throttle_get_percentage()) {
+        return;
+    }
+
+    pct = (double)cpu_throttle_get_percentage()/100;
+    throttle_ratio = pct / (1 - pct);
+    /* Add 1ns to fix double's rounding error (like 0.9999999...) */
+    sleeptime_ns = (int64_t)(throttle_ratio * CPU_THROTTLE_TIMESLICE_NS + 1);
+    endtime_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + sleeptime_ns;
+    while (sleeptime_ns > 0 && !cpu->stop) {
+        if (sleeptime_ns > SCALE_MS) {
+            qemu_cond_timedwait(cpu->halt_cond, &qemu_global_mutex,
+                                sleeptime_ns / SCALE_MS);
+        } else {
+            qemu_mutex_unlock_iothread();
+            g_usleep(sleeptime_ns / SCALE_US);
+            qemu_mutex_lock_iothread();
+        }
+        sleeptime_ns = endtime_ns - qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+    }
+    atomic_set(&cpu->throttle_thread_scheduled, 0);
+}
+
+static void cpu_throttle_timer_tick(void *opaque)
+{
+    CPUState *cpu;
+    double pct;
+
+    /* Stop the timer if needed */
+    if (!cpu_throttle_get_percentage()) {
+        return;
+    }
+    CPU_FOREACH(cpu) {
+        if (!atomic_xchg(&cpu->throttle_thread_scheduled, 1)) {
+            async_run_on_cpu(cpu, cpu_throttle_thread,
+                             RUN_ON_CPU_NULL);
+        }
+    }
+
+    pct = (double)cpu_throttle_get_percentage()/100;
+    timer_mod(throttle_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT) +
+                                   CPU_THROTTLE_TIMESLICE_NS / (1-pct));
+}
+
+void cpu_throttle_set(int new_throttle_pct)
+{
+    /* Ensure throttle percentage is within valid range */
+    new_throttle_pct = MIN(new_throttle_pct, CPU_THROTTLE_PCT_MAX);
+    new_throttle_pct = MAX(new_throttle_pct, CPU_THROTTLE_PCT_MIN);
+
+    atomic_set(&throttle_percentage, new_throttle_pct);
+
+    timer_mod(throttle_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT) +
+                                       CPU_THROTTLE_TIMESLICE_NS);
+}
+
+void cpu_throttle_stop(void)
+{
+    atomic_set(&throttle_percentage, 0);
+}
+
+bool cpu_throttle_active(void)
+{
+    return (cpu_throttle_get_percentage() != 0);
+}
+
+int cpu_throttle_get_percentage(void)
+{
+    return atomic_read(&throttle_percentage);
+}
+
+void cpu_ticks_init(void)
+{
+    seqlock_init(&timers_state.vm_clock_seqlock);
+    qemu_spin_init(&timers_state.vm_clock_lock);
+    vmstate_register(NULL, 0, &vmstate_timers, &timers_state);
+    throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT,
+                                           cpu_throttle_timer_tick, NULL);
+}
+
+void configure_icount(QemuOpts *opts, Error **errp)
+{
+    const char *option = qemu_opt_get(opts, "shift");
+    bool sleep = qemu_opt_get_bool(opts, "sleep", true);
+    bool align = qemu_opt_get_bool(opts, "align", false);
+    long time_shift = -1;
+
+    if (!option) {
+        if (qemu_opt_get(opts, "align") != NULL) {
+            error_setg(errp, "Please specify shift option when using align");
+        }
+        return;
+    }
+
+    if (align && !sleep) {
+        error_setg(errp, "align=on and sleep=off are incompatible");
+        return;
+    }
+
+    if (strcmp(option, "auto") != 0) {
+        if (qemu_strtol(option, NULL, 0, &time_shift) < 0
+            || time_shift < 0 || time_shift > MAX_ICOUNT_SHIFT) {
+            error_setg(errp, "icount: Invalid shift value");
+            return;
+        }
+    } else if (icount_align_option) {
+        error_setg(errp, "shift=auto and align=on are incompatible");
+        return;
+    } else if (!icount_sleep) {
+        error_setg(errp, "shift=auto and sleep=off are incompatible");
+        return;
+    }
+
+    icount_sleep = sleep;
+    if (icount_sleep) {
+        timers_state.icount_warp_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT,
+                                         icount_timer_cb, NULL);
+    }
+
+    icount_align_option = align;
+
+    if (time_shift >= 0) {
+        timers_state.icount_time_shift = time_shift;
+        use_icount = 1;
+        return;
+    }
+
+    use_icount = 2;
+
+    /* 125MIPS seems a reasonable initial guess at the guest speed.
+       It will be corrected fairly quickly anyway.  */
+    timers_state.icount_time_shift = 3;
+
+    /* Have both realtime and virtual time triggers for speed adjustment.
+       The realtime trigger catches emulated time passing too slowly,
+       the virtual time trigger catches emulated time passing too fast.
+       Realtime triggers occur even when idle, so use them less frequently
+       than VM triggers.  */
+    timers_state.vm_clock_warp_start = -1;
+    timers_state.icount_rt_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL_RT,
+                                   icount_adjust_rt, NULL);
+    timer_mod(timers_state.icount_rt_timer,
+                   qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + 1000);
+    timers_state.icount_vm_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
+                                        icount_adjust_vm, NULL);
+    timer_mod(timers_state.icount_vm_timer,
+                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
+                   NANOSECONDS_PER_SECOND / 10);
+}
+
+/***********************************************************/
+/* TCG vCPU kick timer
+ *
+ * The kick timer is responsible for moving single threaded vCPU
+ * emulation on to the next vCPU. If more than one vCPU is running a
+ * timer event with force a cpu->exit so the next vCPU can get
+ * scheduled.
+ *
+ * The timer is removed if all vCPUs are idle and restarted again once
+ * idleness is complete.
+ */
+
+static QEMUTimer *tcg_kick_vcpu_timer;
+static CPUState *tcg_current_rr_cpu;
+
+#define TCG_KICK_PERIOD (NANOSECONDS_PER_SECOND / 10)
+
+static inline int64_t qemu_tcg_next_kick(void)
+{
+    return qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + TCG_KICK_PERIOD;
+}
+
+/* Kick the currently round-robin scheduled vCPU to next */
+static void qemu_cpu_kick_rr_next_cpu(void)
+{
+    CPUState *cpu;
+    do {
+        cpu = atomic_mb_read(&tcg_current_rr_cpu);
+        if (cpu) {
+            cpu_exit(cpu);
+        }
+    } while (cpu != atomic_mb_read(&tcg_current_rr_cpu));
+}
+
+/* Kick all RR vCPUs */
+static void qemu_cpu_kick_rr_cpus(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        cpu_exit(cpu);
+    };
+}
+
+static void do_nothing(CPUState *cpu, run_on_cpu_data unused)
+{
+}
+
+void qemu_timer_notify_cb(void *opaque, QEMUClockType type)
+{
+    if (!use_icount || type != QEMU_CLOCK_VIRTUAL) {
+        qemu_notify_event();
+        return;
+    }
+
+    if (qemu_in_vcpu_thread()) {
+        /* A CPU is currently running; kick it back out to the
+         * tcg_cpu_exec() loop so it will recalculate its
+         * icount deadline immediately.
+         */
+        qemu_cpu_kick(current_cpu);
+    } else if (first_cpu) {
+        /* qemu_cpu_kick is not enough to kick a halted CPU out of
+         * qemu_tcg_wait_io_event.  async_run_on_cpu, instead,
+         * causes cpu_thread_is_idle to return false.  This way,
+         * handle_icount_deadline can run.
+         * If we have no CPUs at all for some reason, we don't
+         * need to do anything.
+         */
+        async_run_on_cpu(first_cpu, do_nothing, RUN_ON_CPU_NULL);
+    }
+}
+
+static void kick_tcg_thread(void *opaque)
+{
+    timer_mod(tcg_kick_vcpu_timer, qemu_tcg_next_kick());
+    qemu_cpu_kick_rr_next_cpu();
+}
+
+static void start_tcg_kick_timer(void)
+{
+    assert(!mttcg_enabled);
+    if (!tcg_kick_vcpu_timer && CPU_NEXT(first_cpu)) {
+        tcg_kick_vcpu_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
+                                           kick_tcg_thread, NULL);
+    }
+    if (tcg_kick_vcpu_timer && !timer_pending(tcg_kick_vcpu_timer)) {
+        timer_mod(tcg_kick_vcpu_timer, qemu_tcg_next_kick());
+    }
+}
+
+static void stop_tcg_kick_timer(void)
+{
+    assert(!mttcg_enabled);
+    if (tcg_kick_vcpu_timer && timer_pending(tcg_kick_vcpu_timer)) {
+        timer_del(tcg_kick_vcpu_timer);
+    }
+}
+
+/***********************************************************/
+void hw_error(const char *fmt, ...)
+{
+    va_list ap;
+    CPUState *cpu;
+
+    va_start(ap, fmt);
+    fprintf(stderr, "qemu: hardware error: ");
+    vfprintf(stderr, fmt, ap);
+    fprintf(stderr, "\n");
+    CPU_FOREACH(cpu) {
+        fprintf(stderr, "CPU #%d:\n", cpu->cpu_index);
+        cpu_dump_state(cpu, stderr, CPU_DUMP_FPU);
+    }
+    va_end(ap);
+    abort();
+}
+
+void cpu_synchronize_all_states(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        cpu_synchronize_state(cpu);
+    }
+}
+
+void cpu_synchronize_all_post_reset(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        cpu_synchronize_post_reset(cpu);
+    }
+}
+
+void cpu_synchronize_all_post_init(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        cpu_synchronize_post_init(cpu);
+    }
+}
+
+void cpu_synchronize_all_pre_loadvm(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        cpu_synchronize_pre_loadvm(cpu);
+    }
+}
+
+static int do_vm_stop(RunState state, bool send_stop)
+{
+    int ret = 0;
+
+    if (runstate_is_running()) {
+        runstate_set(state);
+        cpu_disable_ticks();
+        pause_all_vcpus();
+        vm_state_notify(0, state);
+        if (send_stop) {
+            qapi_event_send_stop();
+        }
+    }
+
+    bdrv_drain_all();
+    ret = bdrv_flush_all();
+
+    return ret;
+}
+
+/* Special vm_stop() variant for terminating the process.  Historically clients
+ * did not expect a QMP STOP event and so we need to retain compatibility.
+ */
+int vm_shutdown(void)
+{
+    return do_vm_stop(RUN_STATE_SHUTDOWN, false);
+}
+
+static bool cpu_can_run(CPUState *cpu)
+{
+    if (cpu->stop) {
+        return false;
+    }
+    if (cpu_is_stopped(cpu)) {
+        return false;
+    }
+    return true;
+}
+
+static void cpu_handle_guest_debug(CPUState *cpu)
+{
+    gdb_set_stop_cpu(cpu);
+    qemu_system_debug_request();
+    cpu->stopped = true;
+}
+
+#ifdef CONFIG_LINUX
+static void sigbus_reraise(void)
+{
+    sigset_t set;
+    struct sigaction action;
+
+    memset(&action, 0, sizeof(action));
+    action.sa_handler = SIG_DFL;
+    if (!sigaction(SIGBUS, &action, NULL)) {
+        raise(SIGBUS);
+        sigemptyset(&set);
+        sigaddset(&set, SIGBUS);
+        pthread_sigmask(SIG_UNBLOCK, &set, NULL);
+    }
+    perror("Failed to re-raise SIGBUS!\n");
+    abort();
+}
+
+static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx)
+{
+    if (siginfo->si_code != BUS_MCEERR_AO && siginfo->si_code != BUS_MCEERR_AR) {
+        sigbus_reraise();
+    }
+
+    if (current_cpu) {
+        /* Called asynchronously in VCPU thread.  */
+        if (kvm_on_sigbus_vcpu(current_cpu, siginfo->si_code, siginfo->si_addr)) {
+            sigbus_reraise();
+        }
+    } else {
+        /* Called synchronously (via signalfd) in main thread.  */
+        if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) {
+            sigbus_reraise();
+        }
+    }
+}
+
+static void qemu_init_sigbus(void)
+{
+    struct sigaction action;
+
+    memset(&action, 0, sizeof(action));
+    action.sa_flags = SA_SIGINFO;
+    action.sa_sigaction = sigbus_handler;
+    sigaction(SIGBUS, &action, NULL);
+
+    prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0);
+}
+#else /* !CONFIG_LINUX */
+static void qemu_init_sigbus(void)
+{
+}
+#endif /* !CONFIG_LINUX */
+
+static QemuThread io_thread;
+
+/* cpu creation */
+static QemuCond qemu_cpu_cond;
+/* system init */
+static QemuCond qemu_pause_cond;
+
+void qemu_init_cpu_loop(void)
+{
+    qemu_init_sigbus();
+    qemu_cond_init(&qemu_cpu_cond);
+    qemu_cond_init(&qemu_pause_cond);
+    qemu_mutex_init(&qemu_global_mutex);
+
+    qemu_thread_get_self(&io_thread);
+}
+
+void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data)
+{
+    do_run_on_cpu(cpu, func, data, &qemu_global_mutex);
+}
+
+static void qemu_kvm_destroy_vcpu(CPUState *cpu)
+{
+    if (kvm_destroy_vcpu(cpu) < 0) {
+        error_report("kvm_destroy_vcpu failed");
+        exit(EXIT_FAILURE);
+    }
+}
+
+static void qemu_tcg_destroy_vcpu(CPUState *cpu)
+{
+}
+
+static void qemu_cpu_stop(CPUState *cpu, bool exit)
+{
+    g_assert(qemu_cpu_is_self(cpu));
+    cpu->stop = false;
+    cpu->stopped = true;
+    if (exit) {
+        cpu_exit(cpu);
+    }
+    qemu_cond_broadcast(&qemu_pause_cond);
+}
+
+static void qemu_wait_io_event_common(CPUState *cpu)
+{
+    atomic_mb_set(&cpu->thread_kicked, false);
+    if (cpu->stop) {
+        qemu_cpu_stop(cpu, false);
+    }
+    process_queued_cpu_work(cpu);
+}
+
+static void qemu_tcg_rr_wait_io_event(void)
+{
+    CPUState *cpu;
+
+    while (all_cpu_threads_idle()) {
+        stop_tcg_kick_timer();
+        qemu_cond_wait(first_cpu->halt_cond, &qemu_global_mutex);
+    }
+
+    start_tcg_kick_timer();
+
+    CPU_FOREACH(cpu) {
+        qemu_wait_io_event_common(cpu);
+    }
+}
+
+static void qemu_wait_io_event(CPUState *cpu)
+{
+    bool slept = false;
+
+    while (cpu_thread_is_idle(cpu)) {
+        if (!slept) {
+            slept = true;
+            qemu_plugin_vcpu_idle_cb(cpu);
+        }
+        qemu_cond_wait(cpu->halt_cond, &qemu_global_mutex);
+    }
+    if (slept) {
+        qemu_plugin_vcpu_resume_cb(cpu);
+    }
+
+#ifdef _WIN32
+    /* Eat dummy APC queued by qemu_cpu_kick_thread.  */
+    if (!tcg_enabled()) {
+        SleepEx(0, TRUE);
+    }
+#endif
+    qemu_wait_io_event_common(cpu);
+}
+
+static void *qemu_kvm_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+    int r;
+
+    rcu_register_thread();
+
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+    cpu->thread_id = qemu_get_thread_id();
+    cpu->can_do_io = 1;
+    current_cpu = cpu;
+
+    r = kvm_init_vcpu(cpu);
+    if (r < 0) {
+        error_report("kvm_init_vcpu failed: %s", strerror(-r));
+        exit(1);
+    }
+
+    kvm_init_cpu_signals(cpu);
+
+    /* signal CPU creation */
+    cpu->created = true;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    do {
+        if (cpu_can_run(cpu)) {
+            r = kvm_cpu_exec(cpu);
+            if (r == EXCP_DEBUG) {
+                cpu_handle_guest_debug(cpu);
+            }
+        }
+        qemu_wait_io_event(cpu);
+    } while (!cpu->unplug || cpu_can_run(cpu));
+
+    qemu_kvm_destroy_vcpu(cpu);
+    cpu->created = false;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_mutex_unlock_iothread();
+    rcu_unregister_thread();
+    return NULL;
+}
+
+static void *qemu_dummy_cpu_thread_fn(void *arg)
+{
+#ifdef _WIN32
+    error_report("qtest is not supported under Windows");
+    exit(1);
+#else
+    CPUState *cpu = arg;
+    sigset_t waitset;
+    int r;
+
+    rcu_register_thread();
+
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+    cpu->thread_id = qemu_get_thread_id();
+    cpu->can_do_io = 1;
+    current_cpu = cpu;
+
+    sigemptyset(&waitset);
+    sigaddset(&waitset, SIG_IPI);
+
+    /* signal CPU creation */
+    cpu->created = true;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    do {
+        qemu_mutex_unlock_iothread();
+        do {
+            int sig;
+            r = sigwait(&waitset, &sig);
+        } while (r == -1 && (errno == EAGAIN || errno == EINTR));
+        if (r == -1) {
+            perror("sigwait");
+            exit(1);
+        }
+        qemu_mutex_lock_iothread();
+        qemu_wait_io_event(cpu);
+    } while (!cpu->unplug);
+
+    qemu_mutex_unlock_iothread();
+    rcu_unregister_thread();
+    return NULL;
+#endif
+}
+
+static int64_t tcg_get_icount_limit(void)
+{
+    int64_t deadline;
+
+    if (replay_mode != REPLAY_MODE_PLAY) {
+        /*
+         * Include all the timers, because they may need an attention.
+         * Too long CPU execution may create unnecessary delay in UI.
+         */
+        deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
+                                              QEMU_TIMER_ATTR_ALL);
+        /* Check realtime timers, because they help with input processing */
+        deadline = qemu_soonest_timeout(deadline,
+                qemu_clock_deadline_ns_all(QEMU_CLOCK_REALTIME,
+                                           QEMU_TIMER_ATTR_ALL));
+
+        /* 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;
+        }
+
+        return qemu_icount_round(deadline);
+    } else {
+        return replay_get_instructions();
+    }
+}
+
+static void notify_aio_contexts(void)
+{
+    /* Wake up other AioContexts.  */
+    qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+    qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
+}
+
+static void handle_icount_deadline(void)
+{
+    assert(qemu_in_vcpu_thread());
+    if (use_icount) {
+        int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
+                                                      QEMU_TIMER_ATTR_ALL);
+
+        if (deadline == 0) {
+            notify_aio_contexts();
+        }
+    }
+}
+
+static void prepare_icount_for_run(CPUState *cpu)
+{
+    if (use_icount) {
+        int insns_left;
+
+        /* These should always be cleared by process_icount_data after
+         * each vCPU execution. However u16.high can be raised
+         * asynchronously by cpu_exit/cpu_interrupt/tcg_handle_interrupt
+         */
+        g_assert(cpu_neg(cpu)->icount_decr.u16.low == 0);
+        g_assert(cpu->icount_extra == 0);
+
+        cpu->icount_budget = tcg_get_icount_limit();
+        insns_left = MIN(0xffff, cpu->icount_budget);
+        cpu_neg(cpu)->icount_decr.u16.low = insns_left;
+        cpu->icount_extra = cpu->icount_budget - insns_left;
+
+        replay_mutex_lock();
+
+        if (cpu->icount_budget == 0 && replay_has_checkpoint()) {
+            notify_aio_contexts();
+        }
+    }
+}
+
+static void process_icount_data(CPUState *cpu)
+{
+    if (use_icount) {
+        /* Account for executed instructions */
+        cpu_update_icount(cpu);
+
+        /* Reset the counters */
+        cpu_neg(cpu)->icount_decr.u16.low = 0;
+        cpu->icount_extra = 0;
+        cpu->icount_budget = 0;
+
+        replay_account_executed_instructions();
+
+        replay_mutex_unlock();
+    }
+}
+
+
+static int tcg_cpu_exec(CPUState *cpu)
+{
+    int ret;
+#ifdef CONFIG_PROFILER
+    int64_t ti;
+#endif
+
+    assert(tcg_enabled());
+#ifdef CONFIG_PROFILER
+    ti = profile_getclock();
+#endif
+    cpu_exec_start(cpu);
+    ret = cpu_exec(cpu);
+    cpu_exec_end(cpu);
+#ifdef CONFIG_PROFILER
+    atomic_set(&tcg_ctx->prof.cpu_exec_time,
+               tcg_ctx->prof.cpu_exec_time + profile_getclock() - ti);
+#endif
+    return ret;
+}
+
+/* Destroy any remaining vCPUs which have been unplugged and have
+ * finished running
+ */
+static void deal_with_unplugged_cpus(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        if (cpu->unplug && !cpu_can_run(cpu)) {
+            qemu_tcg_destroy_vcpu(cpu);
+            cpu->created = false;
+            qemu_cond_signal(&qemu_cpu_cond);
+            break;
+        }
+    }
+}
+
+/* Single-threaded TCG
+ *
+ * In the single-threaded case each vCPU is simulated in turn. If
+ * there is more than a single vCPU we create a simple timer to kick
+ * the vCPU and ensure we don't get stuck in a tight loop in one vCPU.
+ * This is done explicitly rather than relying on side-effects
+ * elsewhere.
+ */
+
+static void *qemu_tcg_rr_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+
+    assert(tcg_enabled());
+    rcu_register_thread();
+    tcg_register_thread();
+
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+
+    cpu->thread_id = qemu_get_thread_id();
+    cpu->created = true;
+    cpu->can_do_io = 1;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    /* wait for initial kick-off after machine start */
+    while (first_cpu->stopped) {
+        qemu_cond_wait(first_cpu->halt_cond, &qemu_global_mutex);
+
+        /* process any pending work */
+        CPU_FOREACH(cpu) {
+            current_cpu = cpu;
+            qemu_wait_io_event_common(cpu);
+        }
+    }
+
+    start_tcg_kick_timer();
+
+    cpu = first_cpu;
+
+    /* process any pending work */
+    cpu->exit_request = 1;
+
+    while (1) {
+        qemu_mutex_unlock_iothread();
+        replay_mutex_lock();
+        qemu_mutex_lock_iothread();
+        /* Account partial waits to QEMU_CLOCK_VIRTUAL.  */
+        qemu_account_warp_timer();
+
+        /* Run the timers here.  This is much more efficient than
+         * waking up the I/O thread and waiting for completion.
+         */
+        handle_icount_deadline();
+
+        replay_mutex_unlock();
+
+        if (!cpu) {
+            cpu = first_cpu;
+        }
+
+        while (cpu && cpu_work_list_empty(cpu) && !cpu->exit_request) {
+
+            atomic_mb_set(&tcg_current_rr_cpu, cpu);
+            current_cpu = cpu;
+
+            qemu_clock_enable(QEMU_CLOCK_VIRTUAL,
+                              (cpu->singlestep_enabled & SSTEP_NOTIMER) == 0);
+
+            if (cpu_can_run(cpu)) {
+                int r;
+
+                qemu_mutex_unlock_iothread();
+                prepare_icount_for_run(cpu);
+
+                r = tcg_cpu_exec(cpu);
+
+                process_icount_data(cpu);
+                qemu_mutex_lock_iothread();
+
+                if (r == EXCP_DEBUG) {
+                    cpu_handle_guest_debug(cpu);
+                    break;
+                } else if (r == EXCP_ATOMIC) {
+                    qemu_mutex_unlock_iothread();
+                    cpu_exec_step_atomic(cpu);
+                    qemu_mutex_lock_iothread();
+                    break;
+                }
+            } else if (cpu->stop) {
+                if (cpu->unplug) {
+                    cpu = CPU_NEXT(cpu);
+                }
+                break;
+            }
+
+            cpu = CPU_NEXT(cpu);
+        } /* while (cpu && !cpu->exit_request).. */
+
+        /* Does not need atomic_mb_set because a spurious wakeup is okay.  */
+        atomic_set(&tcg_current_rr_cpu, NULL);
+
+        if (cpu && cpu->exit_request) {
+            atomic_mb_set(&cpu->exit_request, 0);
+        }
+
+        if (use_icount && all_cpu_threads_idle()) {
+            /*
+             * When all cpus are sleeping (e.g in WFI), to avoid a deadlock
+             * in the main_loop, wake it up in order to start the warp timer.
+             */
+            qemu_notify_event();
+        }
+
+        qemu_tcg_rr_wait_io_event();
+        deal_with_unplugged_cpus();
+    }
+
+    rcu_unregister_thread();
+    return NULL;
+}
+
+static void *qemu_hax_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+    int r;
+
+    rcu_register_thread();
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+
+    cpu->thread_id = qemu_get_thread_id();
+    cpu->created = true;
+    current_cpu = cpu;
+
+    hax_init_vcpu(cpu);
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    do {
+        if (cpu_can_run(cpu)) {
+            r = hax_smp_cpu_exec(cpu);
+            if (r == EXCP_DEBUG) {
+                cpu_handle_guest_debug(cpu);
+            }
+        }
+
+        qemu_wait_io_event(cpu);
+    } while (!cpu->unplug || cpu_can_run(cpu));
+    rcu_unregister_thread();
+    return NULL;
+}
+
+/* The HVF-specific vCPU thread function. This one should only run when the host
+ * CPU supports the VMX "unrestricted guest" feature. */
+static void *qemu_hvf_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+
+    int r;
+
+    assert(hvf_enabled());
+
+    rcu_register_thread();
+
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+
+    cpu->thread_id = qemu_get_thread_id();
+    cpu->can_do_io = 1;
+    current_cpu = cpu;
+
+    hvf_init_vcpu(cpu);
+
+    /* signal CPU creation */
+    cpu->created = true;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    do {
+        if (cpu_can_run(cpu)) {
+            r = hvf_vcpu_exec(cpu);
+            if (r == EXCP_DEBUG) {
+                cpu_handle_guest_debug(cpu);
+            }
+        }
+        qemu_wait_io_event(cpu);
+    } while (!cpu->unplug || cpu_can_run(cpu));
+
+    hvf_vcpu_destroy(cpu);
+    cpu->created = false;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_mutex_unlock_iothread();
+    rcu_unregister_thread();
+    return NULL;
+}
+
+static void *qemu_whpx_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+    int r;
+
+    rcu_register_thread();
+
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+    cpu->thread_id = qemu_get_thread_id();
+    current_cpu = cpu;
+
+    r = whpx_init_vcpu(cpu);
+    if (r < 0) {
+        fprintf(stderr, "whpx_init_vcpu failed: %s\n", strerror(-r));
+        exit(1);
+    }
+
+    /* signal CPU creation */
+    cpu->created = true;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    do {
+        if (cpu_can_run(cpu)) {
+            r = whpx_vcpu_exec(cpu);
+            if (r == EXCP_DEBUG) {
+                cpu_handle_guest_debug(cpu);
+            }
+        }
+        while (cpu_thread_is_idle(cpu)) {
+            qemu_cond_wait(cpu->halt_cond, &qemu_global_mutex);
+        }
+        qemu_wait_io_event_common(cpu);
+    } while (!cpu->unplug || cpu_can_run(cpu));
+
+    whpx_destroy_vcpu(cpu);
+    cpu->created = false;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_mutex_unlock_iothread();
+    rcu_unregister_thread();
+    return NULL;
+}
+
+#ifdef _WIN32
+static void CALLBACK dummy_apc_func(ULONG_PTR unused)
+{
+}
+#endif
+
+/* Multi-threaded TCG
+ *
+ * In the multi-threaded case each vCPU has its own thread. The TLS
+ * variable current_cpu can be used deep in the code to find the
+ * current CPUState for a given thread.
+ */
+
+static void *qemu_tcg_cpu_thread_fn(void *arg)
+{
+    CPUState *cpu = arg;
+
+    assert(tcg_enabled());
+    g_assert(!use_icount);
+
+    rcu_register_thread();
+    tcg_register_thread();
+
+    qemu_mutex_lock_iothread();
+    qemu_thread_get_self(cpu->thread);
+
+    cpu->thread_id = qemu_get_thread_id();
+    cpu->created = true;
+    cpu->can_do_io = 1;
+    current_cpu = cpu;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_guest_random_seed_thread_part2(cpu->random_seed);
+
+    /* process any pending work */
+    cpu->exit_request = 1;
+
+    do {
+        if (cpu_can_run(cpu)) {
+            int r;
+            qemu_mutex_unlock_iothread();
+            r = tcg_cpu_exec(cpu);
+            qemu_mutex_lock_iothread();
+            switch (r) {
+            case EXCP_DEBUG:
+                cpu_handle_guest_debug(cpu);
+                break;
+            case EXCP_HALTED:
+                /* during start-up the vCPU is reset and the thread is
+                 * kicked several times. If we don't ensure we go back
+                 * to sleep in the halted state we won't cleanly
+                 * start-up when the vCPU is enabled.
+                 *
+                 * cpu->halted should ensure we sleep in wait_io_event
+                 */
+                g_assert(cpu->halted);
+                break;
+            case EXCP_ATOMIC:
+                qemu_mutex_unlock_iothread();
+                cpu_exec_step_atomic(cpu);
+                qemu_mutex_lock_iothread();
+            default:
+                /* Ignore everything else? */
+                break;
+            }
+        }
+
+        atomic_mb_set(&cpu->exit_request, 0);
+        qemu_wait_io_event(cpu);
+    } while (!cpu->unplug || cpu_can_run(cpu));
+
+    qemu_tcg_destroy_vcpu(cpu);
+    cpu->created = false;
+    qemu_cond_signal(&qemu_cpu_cond);
+    qemu_mutex_unlock_iothread();
+    rcu_unregister_thread();
+    return NULL;
+}
+
+static void qemu_cpu_kick_thread(CPUState *cpu)
+{
+#ifndef _WIN32
+    int err;
+
+    if (cpu->thread_kicked) {
+        return;
+    }
+    cpu->thread_kicked = true;
+    err = pthread_kill(cpu->thread->thread, SIG_IPI);
+    if (err && err != ESRCH) {
+        fprintf(stderr, "qemu:%s: %s", __func__, strerror(err));
+        exit(1);
+    }
+#else /* _WIN32 */
+    if (!qemu_cpu_is_self(cpu)) {
+        if (whpx_enabled()) {
+            whpx_vcpu_kick(cpu);
+        } else if (!QueueUserAPC(dummy_apc_func, cpu->hThread, 0)) {
+            fprintf(stderr, "%s: QueueUserAPC failed with error %lu\n",
+                    __func__, GetLastError());
+            exit(1);
+        }
+    }
+#endif
+}
+
+void qemu_cpu_kick(CPUState *cpu)
+{
+    qemu_cond_broadcast(cpu->halt_cond);
+    if (tcg_enabled()) {
+        if (qemu_tcg_mttcg_enabled()) {
+            cpu_exit(cpu);
+        } else {
+            qemu_cpu_kick_rr_cpus();
+        }
+    } else {
+        if (hax_enabled()) {
+            /*
+             * FIXME: race condition with the exit_request check in
+             * hax_vcpu_hax_exec
+             */
+            cpu->exit_request = 1;
+        }
+        qemu_cpu_kick_thread(cpu);
+    }
+}
+
+void qemu_cpu_kick_self(void)
+{
+    assert(current_cpu);
+    qemu_cpu_kick_thread(current_cpu);
+}
+
+bool qemu_cpu_is_self(CPUState *cpu)
+{
+    return qemu_thread_is_self(cpu->thread);
+}
+
+bool qemu_in_vcpu_thread(void)
+{
+    return current_cpu && qemu_cpu_is_self(current_cpu);
+}
+
+static __thread bool iothread_locked = false;
+
+bool qemu_mutex_iothread_locked(void)
+{
+    return iothread_locked;
+}
+
+/*
+ * The BQL is taken from so many places that it is worth profiling the
+ * callers directly, instead of funneling them all through a single function.
+ */
+void qemu_mutex_lock_iothread_impl(const char *file, int line)
+{
+    QemuMutexLockFunc bql_lock = atomic_read(&qemu_bql_mutex_lock_func);
+
+    g_assert(!qemu_mutex_iothread_locked());
+    bql_lock(&qemu_global_mutex, file, line);
+    iothread_locked = true;
+}
+
+void qemu_mutex_unlock_iothread(void)
+{
+    g_assert(qemu_mutex_iothread_locked());
+    iothread_locked = false;
+    qemu_mutex_unlock(&qemu_global_mutex);
+}
+
+void qemu_cond_wait_iothread(QemuCond *cond)
+{
+    qemu_cond_wait(cond, &qemu_global_mutex);
+}
+
+static bool all_vcpus_paused(void)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        if (!cpu->stopped) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void pause_all_vcpus(void)
+{
+    CPUState *cpu;
+
+    qemu_clock_enable(QEMU_CLOCK_VIRTUAL, false);
+    CPU_FOREACH(cpu) {
+        if (qemu_cpu_is_self(cpu)) {
+            qemu_cpu_stop(cpu, true);
+        } else {
+            cpu->stop = true;
+            qemu_cpu_kick(cpu);
+        }
+    }
+
+    /* We need to drop the replay_lock so any vCPU threads woken up
+     * can finish their replay tasks
+     */
+    replay_mutex_unlock();
+
+    while (!all_vcpus_paused()) {
+        qemu_cond_wait(&qemu_pause_cond, &qemu_global_mutex);
+        CPU_FOREACH(cpu) {
+            qemu_cpu_kick(cpu);
+        }
+    }
+
+    qemu_mutex_unlock_iothread();
+    replay_mutex_lock();
+    qemu_mutex_lock_iothread();
+}
+
+void cpu_resume(CPUState *cpu)
+{
+    cpu->stop = false;
+    cpu->stopped = false;
+    qemu_cpu_kick(cpu);
+}
+
+void resume_all_vcpus(void)
+{
+    CPUState *cpu;
+
+    if (!runstate_is_running()) {
+        return;
+    }
+
+    qemu_clock_enable(QEMU_CLOCK_VIRTUAL, true);
+    CPU_FOREACH(cpu) {
+        cpu_resume(cpu);
+    }
+}
+
+void cpu_remove_sync(CPUState *cpu)
+{
+    cpu->stop = true;
+    cpu->unplug = true;
+    qemu_cpu_kick(cpu);
+    qemu_mutex_unlock_iothread();
+    qemu_thread_join(cpu->thread);
+    qemu_mutex_lock_iothread();
+}
+
+/* For temporary buffers for forming a name */
+#define VCPU_THREAD_NAME_SIZE 16
+
+static void qemu_tcg_init_vcpu(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+    static QemuCond *single_tcg_halt_cond;
+    static QemuThread *single_tcg_cpu_thread;
+    static int tcg_region_inited;
+
+    assert(tcg_enabled());
+    /*
+     * Initialize TCG regions--once. Now is a good time, because:
+     * (1) TCG's init context, prologue and target globals have been set up.
+     * (2) qemu_tcg_mttcg_enabled() works now (TCG init code runs before the
+     *     -accel flag is processed, so the check doesn't work then).
+     */
+    if (!tcg_region_inited) {
+        tcg_region_inited = 1;
+        tcg_region_init();
+    }
+
+    if (qemu_tcg_mttcg_enabled() || !single_tcg_cpu_thread) {
+        cpu->thread = g_malloc0(sizeof(QemuThread));
+        cpu->halt_cond = g_malloc0(sizeof(QemuCond));
+        qemu_cond_init(cpu->halt_cond);
+
+        if (qemu_tcg_mttcg_enabled()) {
+            /* create a thread per vCPU with TCG (MTTCG) */
+            parallel_cpus = true;
+            snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/TCG",
+                 cpu->cpu_index);
+
+            qemu_thread_create(cpu->thread, thread_name, qemu_tcg_cpu_thread_fn,
+                               cpu, QEMU_THREAD_JOINABLE);
+
+        } else {
+            /* share a single thread for all cpus with TCG */
+            snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "ALL CPUs/TCG");
+            qemu_thread_create(cpu->thread, thread_name,
+                               qemu_tcg_rr_cpu_thread_fn,
+                               cpu, QEMU_THREAD_JOINABLE);
+
+            single_tcg_halt_cond = cpu->halt_cond;
+            single_tcg_cpu_thread = cpu->thread;
+        }
+#ifdef _WIN32
+        cpu->hThread = qemu_thread_get_handle(cpu->thread);
+#endif
+    } else {
+        /* For non-MTTCG cases we share the thread */
+        cpu->thread = single_tcg_cpu_thread;
+        cpu->halt_cond = single_tcg_halt_cond;
+        cpu->thread_id = first_cpu->thread_id;
+        cpu->can_do_io = 1;
+        cpu->created = true;
+    }
+}
+
+static void qemu_hax_start_vcpu(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+
+    cpu->thread = g_malloc0(sizeof(QemuThread));
+    cpu->halt_cond = g_malloc0(sizeof(QemuCond));
+    qemu_cond_init(cpu->halt_cond);
+
+    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/HAX",
+             cpu->cpu_index);
+    qemu_thread_create(cpu->thread, thread_name, qemu_hax_cpu_thread_fn,
+                       cpu, QEMU_THREAD_JOINABLE);
+#ifdef _WIN32
+    cpu->hThread = qemu_thread_get_handle(cpu->thread);
+#endif
+}
+
+static void qemu_kvm_start_vcpu(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+
+    cpu->thread = g_malloc0(sizeof(QemuThread));
+    cpu->halt_cond = g_malloc0(sizeof(QemuCond));
+    qemu_cond_init(cpu->halt_cond);
+    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/KVM",
+             cpu->cpu_index);
+    qemu_thread_create(cpu->thread, thread_name, qemu_kvm_cpu_thread_fn,
+                       cpu, QEMU_THREAD_JOINABLE);
+}
+
+static void qemu_hvf_start_vcpu(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+
+    /* HVF currently does not support TCG, and only runs in
+     * unrestricted-guest mode. */
+    assert(hvf_enabled());
+
+    cpu->thread = g_malloc0(sizeof(QemuThread));
+    cpu->halt_cond = g_malloc0(sizeof(QemuCond));
+    qemu_cond_init(cpu->halt_cond);
+
+    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/HVF",
+             cpu->cpu_index);
+    qemu_thread_create(cpu->thread, thread_name, qemu_hvf_cpu_thread_fn,
+                       cpu, QEMU_THREAD_JOINABLE);
+}
+
+static void qemu_whpx_start_vcpu(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+
+    cpu->thread = g_malloc0(sizeof(QemuThread));
+    cpu->halt_cond = g_malloc0(sizeof(QemuCond));
+    qemu_cond_init(cpu->halt_cond);
+    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/WHPX",
+             cpu->cpu_index);
+    qemu_thread_create(cpu->thread, thread_name, qemu_whpx_cpu_thread_fn,
+                       cpu, QEMU_THREAD_JOINABLE);
+#ifdef _WIN32
+    cpu->hThread = qemu_thread_get_handle(cpu->thread);
+#endif
+}
+
+static void qemu_dummy_start_vcpu(CPUState *cpu)
+{
+    char thread_name[VCPU_THREAD_NAME_SIZE];
+
+    cpu->thread = g_malloc0(sizeof(QemuThread));
+    cpu->halt_cond = g_malloc0(sizeof(QemuCond));
+    qemu_cond_init(cpu->halt_cond);
+    snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/DUMMY",
+             cpu->cpu_index);
+    qemu_thread_create(cpu->thread, thread_name, qemu_dummy_cpu_thread_fn, cpu,
+                       QEMU_THREAD_JOINABLE);
+}
+
+void qemu_init_vcpu(CPUState *cpu)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+
+    cpu->nr_cores = ms->smp.cores;
+    cpu->nr_threads =  ms->smp.threads;
+    cpu->stopped = true;
+    cpu->random_seed = qemu_guest_random_seed_thread_part1();
+
+    if (!cpu->as) {
+        /* If the target cpu hasn't set up any address spaces itself,
+         * give it the default one.
+         */
+        cpu->num_ases = 1;
+        cpu_address_space_init(cpu, 0, "cpu-memory", cpu->memory);
+    }
+
+    if (kvm_enabled()) {
+        qemu_kvm_start_vcpu(cpu);
+    } else if (hax_enabled()) {
+        qemu_hax_start_vcpu(cpu);
+    } else if (hvf_enabled()) {
+        qemu_hvf_start_vcpu(cpu);
+    } else if (tcg_enabled()) {
+        qemu_tcg_init_vcpu(cpu);
+    } else if (whpx_enabled()) {
+        qemu_whpx_start_vcpu(cpu);
+    } else {
+        qemu_dummy_start_vcpu(cpu);
+    }
+
+    while (!cpu->created) {
+        qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
+    }
+}
+
+void cpu_stop_current(void)
+{
+    if (current_cpu) {
+        current_cpu->stop = true;
+        cpu_exit(current_cpu);
+    }
+}
+
+int vm_stop(RunState state)
+{
+    if (qemu_in_vcpu_thread()) {
+        qemu_system_vmstop_request_prepare();
+        qemu_system_vmstop_request(state);
+        /*
+         * FIXME: should not return to device code in case
+         * vm_stop() has been requested.
+         */
+        cpu_stop_current();
+        return 0;
+    }
+
+    return do_vm_stop(state, true);
+}
+
+/**
+ * Prepare for (re)starting the VM.
+ * Returns -1 if the vCPUs are not to be restarted (e.g. if they are already
+ * running or in case of an error condition), 0 otherwise.
+ */
+int vm_prepare_start(void)
+{
+    RunState requested;
+
+    qemu_vmstop_requested(&requested);
+    if (runstate_is_running() && requested == RUN_STATE__MAX) {
+        return -1;
+    }
+
+    /* Ensure that a STOP/RESUME pair of events is emitted if a
+     * vmstop request was pending.  The BLOCK_IO_ERROR event, for
+     * example, according to documentation is always followed by
+     * the STOP event.
+     */
+    if (runstate_is_running()) {
+        qapi_event_send_stop();
+        qapi_event_send_resume();
+        return -1;
+    }
+
+    /* We are sending this now, but the CPUs will be resumed shortly later */
+    qapi_event_send_resume();
+
+    cpu_enable_ticks();
+    runstate_set(RUN_STATE_RUNNING);
+    vm_state_notify(1, RUN_STATE_RUNNING);
+    return 0;
+}
+
+void vm_start(void)
+{
+    if (!vm_prepare_start()) {
+        resume_all_vcpus();
+    }
+}
+
+/* does a state transition even if the VM is already stopped,
+   current state is forgotten forever */
+int vm_stop_force_state(RunState state)
+{
+    if (runstate_is_running()) {
+        return vm_stop(state);
+    } else {
+        runstate_set(state);
+
+        bdrv_drain_all();
+        /* Make sure to return an error if the flush in a previous vm_stop()
+         * failed. */
+        return bdrv_flush_all();
+    }
+}
+
+void list_cpus(const char *optarg)
+{
+    /* XXX: implement xxx_cpu_list for targets that still miss it */
+#if defined(cpu_list)
+    cpu_list();
+#endif
+}
+
+void qmp_memsave(int64_t addr, int64_t size, const char *filename,
+                 bool has_cpu, int64_t cpu_index, Error **errp)
+{
+    FILE *f;
+    uint32_t l;
+    CPUState *cpu;
+    uint8_t buf[1024];
+    int64_t orig_addr = addr, orig_size = size;
+
+    if (!has_cpu) {
+        cpu_index = 0;
+    }
+
+    cpu = qemu_get_cpu(cpu_index);
+    if (cpu == NULL) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index",
+                   "a CPU number");
+        return;
+    }
+
+    f = fopen(filename, "wb");
+    if (!f) {
+        error_setg_file_open(errp, errno, filename);
+        return;
+    }
+
+    while (size != 0) {
+        l = sizeof(buf);
+        if (l > size)
+            l = size;
+        if (cpu_memory_rw_debug(cpu, addr, buf, l, 0) != 0) {
+            error_setg(errp, "Invalid addr 0x%016" PRIx64 "/size %" PRId64
+                             " specified", orig_addr, orig_size);
+            goto exit;
+        }
+        if (fwrite(buf, 1, l, f) != l) {
+            error_setg(errp, QERR_IO_ERROR);
+            goto exit;
+        }
+        addr += l;
+        size -= l;
+    }
+
+exit:
+    fclose(f);
+}
+
+void qmp_pmemsave(int64_t addr, int64_t size, const char *filename,
+                  Error **errp)
+{
+    FILE *f;
+    uint32_t l;
+    uint8_t buf[1024];
+
+    f = fopen(filename, "wb");
+    if (!f) {
+        error_setg_file_open(errp, errno, filename);
+        return;
+    }
+
+    while (size != 0) {
+        l = sizeof(buf);
+        if (l > size)
+            l = size;
+        cpu_physical_memory_read(addr, buf, l);
+        if (fwrite(buf, 1, l, f) != l) {
+            error_setg(errp, QERR_IO_ERROR);
+            goto exit;
+        }
+        addr += l;
+        size -= l;
+    }
+
+exit:
+    fclose(f);
+}
+
+void qmp_inject_nmi(Error **errp)
+{
+    nmi_monitor_handle(monitor_get_cpu_index(), errp);
+}
+
+void dump_drift_info(void)
+{
+    if (!use_icount) {
+        return;
+    }
+
+    qemu_printf("Host - Guest clock  %"PRIi64" ms\n",
+                (cpu_get_clock() - cpu_get_icount())/SCALE_MS);
+    if (icount_align_option) {
+        qemu_printf("Max guest delay     %"PRIi64" ms\n",
+                    -max_delay / SCALE_MS);
+        qemu_printf("Max guest advance   %"PRIi64" ms\n",
+                    max_advance / SCALE_MS);
+    } else {
+        qemu_printf("Max guest delay     NA\n");
+        qemu_printf("Max guest advance   NA\n");
+    }
+}