#include "sysemu/qtest.h"
#include "qemu/main-loop.h"
#include "qemu/bitmap.h"
+#include "qemu/seqlock.h"
#ifndef _WIN32
#include "qemu/compatfd.h"
if (cpu_is_stopped(cpu)) {
return true;
}
- if (!cpu->halted || qemu_cpu_has_work(cpu) ||
+ if (!cpu->halted || cpu_has_work(cpu) ||
kvm_halt_in_kernel()) {
return false;
}
/***********************************************************/
/* guest cycle counter */
+/* Protected by TimersState seqlock */
+
+/* Compensate for varying guest execution speed. */
+static int64_t qemu_icount_bias;
+static int64_t vm_clock_warp_start;
/* Conversion factor from emulated instructions to virtual clock ticks. */
static int icount_time_shift;
/* Arbitrarily pick 1MIPS as the minimum allowable speed. */
#define MAX_ICOUNT_SHIFT 10
-/* Compensate for varying guest execution speed. */
-static int64_t qemu_icount_bias;
+
+/* Only written by TCG thread */
+static int64_t qemu_icount;
+
static QEMUTimer *icount_rt_timer;
static QEMUTimer *icount_vm_timer;
static QEMUTimer *icount_warp_timer;
-static int64_t vm_clock_warp_start;
-static int64_t qemu_icount;
typedef struct TimersState {
+ /* Protected by BQL. */
int64_t cpu_ticks_prev;
int64_t cpu_ticks_offset;
+
+ /* cpu_clock_offset can be read out of BQL, so protect it with
+ * this lock.
+ */
+ QemuSeqLock vm_clock_seqlock;
int64_t cpu_clock_offset;
int32_t cpu_ticks_enabled;
int64_t dummy;
static TimersState timers_state;
/* Return the virtual CPU time, based on the instruction counter. */
-int64_t cpu_get_icount(void)
+static int64_t cpu_get_icount_locked(void)
{
int64_t icount;
CPUState *cpu = current_cpu;
icount = qemu_icount;
if (cpu) {
- CPUArchState *env = cpu->env_ptr;
- if (!can_do_io(env)) {
+ if (!cpu_can_do_io(cpu)) {
fprintf(stderr, "Bad clock read\n");
}
- icount -= (env->icount_decr.u16.low + env->icount_extra);
+ icount -= (cpu->icount_decr.u16.low + cpu->icount_extra);
}
return qemu_icount_bias + (icount << icount_time_shift);
}
+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;
+}
+
/* return the host CPU cycle counter and handle stop/restart */
+/* Caller must hold the BQL */
int64_t cpu_get_ticks(void)
{
+ int64_t ticks;
+
if (use_icount) {
return cpu_get_icount();
}
- if (!timers_state.cpu_ticks_enabled) {
- return timers_state.cpu_ticks_offset;
- } else {
- int64_t ticks;
- ticks = cpu_get_real_ticks();
- if (timers_state.cpu_ticks_prev > ticks) {
- /* Note: non increasing ticks may happen if the host uses
- software suspend */
- timers_state.cpu_ticks_offset += timers_state.cpu_ticks_prev - ticks;
- }
- timers_state.cpu_ticks_prev = ticks;
- return ticks + timers_state.cpu_ticks_offset;
+
+ ticks = timers_state.cpu_ticks_offset;
+ if (timers_state.cpu_ticks_enabled) {
+ ticks += cpu_get_real_ticks();
}
+
+ if (timers_state.cpu_ticks_prev > ticks) {
+ /* Note: 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;
+}
+
+static int64_t cpu_get_clock_locked(void)
+{
+ int64_t ticks;
+
+ ticks = timers_state.cpu_clock_offset;
+ if (timers_state.cpu_ticks_enabled) {
+ ticks += get_clock();
+ }
+
+ return ticks;
}
/* return the host CPU monotonic timer and handle stop/restart */
int64_t cpu_get_clock(void)
{
int64_t ti;
- if (!timers_state.cpu_ticks_enabled) {
- return timers_state.cpu_clock_offset;
- } else {
- ti = get_clock();
- return ti + timers_state.cpu_clock_offset;
- }
+ 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() */
+/* enable cpu_get_ticks()
+ * Caller must hold BQL which server as mutex for vm_clock_seqlock.
+ */
void cpu_enable_ticks(void)
{
+ /* Here, the really thing protected by seqlock is cpu_clock_offset. */
+ seqlock_write_lock(&timers_state.vm_clock_seqlock);
if (!timers_state.cpu_ticks_enabled) {
timers_state.cpu_ticks_offset -= cpu_get_real_ticks();
timers_state.cpu_clock_offset -= get_clock();
timers_state.cpu_ticks_enabled = 1;
}
+ seqlock_write_unlock(&timers_state.vm_clock_seqlock);
}
/* disable cpu_get_ticks() : the clock is stopped. You must not call
- cpu_get_ticks() after that. */
+ * cpu_get_ticks() after that.
+ * Caller must hold BQL which server as mutex for vm_clock_seqlock.
+ */
void cpu_disable_ticks(void)
{
+ /* Here, the really thing protected by seqlock is cpu_clock_offset. */
+ seqlock_write_lock(&timers_state.vm_clock_seqlock);
if (timers_state.cpu_ticks_enabled) {
- timers_state.cpu_ticks_offset = cpu_get_ticks();
- timers_state.cpu_clock_offset = cpu_get_clock();
+ timers_state.cpu_ticks_offset += cpu_get_real_ticks();
+ timers_state.cpu_clock_offset = cpu_get_clock_locked();
timers_state.cpu_ticks_enabled = 0;
}
+ seqlock_write_unlock(&timers_state.vm_clock_seqlock);
}
/* Correlation between real and virtual time is always going to be
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;
}
- cur_time = cpu_get_clock();
- cur_icount = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+
+ seqlock_write_lock(&timers_state.vm_clock_seqlock);
+ cur_time = 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 = delta;
qemu_icount_bias = cur_icount - (qemu_icount << icount_time_shift);
+ seqlock_write_unlock(&timers_state.vm_clock_seqlock);
}
static void icount_adjust_rt(void *opaque)
static void icount_warp_rt(void *opaque)
{
- if (vm_clock_warp_start == -1) {
+ /* The icount_warp_timer is rescheduled soon after vm_clock_warp_start
+ * changes from -1 to another value, so the race here is okay.
+ */
+ if (atomic_read(&vm_clock_warp_start) == -1) {
return;
}
+ seqlock_write_lock(&timers_state.vm_clock_seqlock);
if (runstate_is_running()) {
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 {
+ int64_t warp_delta;
+
+ warp_delta = clock - 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_time = cpu_get_clock();
- int64_t cur_icount = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+ int64_t cur_time = cpu_get_clock_locked();
+ int64_t cur_icount = cpu_get_icount_locked();
int64_t delta = cur_time - cur_icount;
- qemu_icount_bias += MIN(warp_delta, delta);
- }
- if (qemu_clock_expired(QEMU_CLOCK_VIRTUAL)) {
- qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+ warp_delta = MIN(warp_delta, delta);
}
+ qemu_icount_bias += warp_delta;
}
vm_clock_warp_start = -1;
+ seqlock_write_unlock(&timers_state.vm_clock_seqlock);
+
+ if (qemu_clock_expired(QEMU_CLOCK_VIRTUAL)) {
+ qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
+ }
}
void qtest_clock_warp(int64_t dest)
while (clock < dest) {
int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
int64_t warp = MIN(dest - clock, deadline);
+ seqlock_write_lock(&timers_state.vm_clock_seqlock);
qemu_icount_bias += warp;
+ seqlock_write_unlock(&timers_state.vm_clock_seqlock);
+
qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
}
void qemu_clock_warp(QEMUClockType type)
{
+ int64_t clock;
int64_t deadline;
/*
* the earliest QEMU_CLOCK_VIRTUAL timer.
*/
icount_warp_rt(NULL);
- if (!all_cpu_threads_idle() || !qemu_clock_has_timers(QEMU_CLOCK_VIRTUAL)) {
- timer_del(icount_warp_timer);
+ timer_del(icount_warp_timer);
+ if (!all_cpu_threads_idle()) {
return;
}
return;
}
- vm_clock_warp_start = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
/* We want to use the earliest deadline from ALL vm_clocks */
+ clock = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
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) {
+ return;
}
if (deadline > 0) {
* you will not be sending network packets continuously instead of
* every 100ms.
*/
- timer_mod(icount_warp_timer, vm_clock_warp_start + deadline);
+ seqlock_write_lock(&timers_state.vm_clock_seqlock);
+ if (vm_clock_warp_start == -1 || vm_clock_warp_start > clock) {
+ vm_clock_warp_start = clock;
+ }
+ seqlock_write_unlock(&timers_state.vm_clock_seqlock);
+ timer_mod_anticipate(icount_warp_timer, clock + deadline);
} else if (deadline == 0) {
qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
}
.name = "timer",
.version_id = 2,
.minimum_version_id = 1,
- .minimum_version_id_old = 1,
- .fields = (VMStateField[]) {
+ .fields = (VMStateField[]) {
VMSTATE_INT64(cpu_ticks_offset, TimersState),
VMSTATE_INT64(dummy, TimersState),
VMSTATE_INT64_V(cpu_clock_offset, TimersState, 2),
void configure_icount(const char *option)
{
+ seqlock_init(&timers_state.vm_clock_seqlock, NULL);
vmstate_register(NULL, 0, &vmstate_timers, &timers_state);
if (!option) {
return;
}
}
+/* 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];
+
+ tcg_cpu_address_space_init(cpu, cpu->as);
+
/* share a single thread for all cpus with TCG */
if (!tcg_cpu_thread) {
cpu->thread = g_malloc0(sizeof(QemuThread));
cpu->halt_cond = g_malloc0(sizeof(QemuCond));
qemu_cond_init(cpu->halt_cond);
tcg_halt_cond = cpu->halt_cond;
- qemu_thread_create(cpu->thread, qemu_tcg_cpu_thread_fn, cpu,
- QEMU_THREAD_JOINABLE);
+ 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);
#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);
- qemu_thread_create(cpu->thread, qemu_kvm_cpu_thread_fn, cpu,
- QEMU_THREAD_JOINABLE);
+ 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);
while (!cpu->created) {
qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
}
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);
- qemu_thread_create(cpu->thread, qemu_dummy_cpu_thread_fn, cpu,
+ 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);
while (!cpu->created) {
qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex);
static int tcg_cpu_exec(CPUArchState *env)
{
+ CPUState *cpu = ENV_GET_CPU(env);
int ret;
#ifdef CONFIG_PROFILER
int64_t ti;
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;
+ qemu_icount -= (cpu->icount_decr.u16.low + cpu->icount_extra);
+ cpu->icount_decr.u16.low = 0;
+ cpu->icount_extra = 0;
deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
/* Maintain prior (possibly buggy) behaviour where if no deadline
qemu_icount += count;
decr = (count > 0xffff) ? 0xffff : count;
count -= decr;
- env->icount_decr.u16.low = decr;
- env->icount_extra = count;
+ cpu->icount_decr.u16.low = decr;
+ cpu->icount_extra = count;
}
ret = cpu_exec(env);
#ifdef CONFIG_PROFILER
if (use_icount) {
/* Fold pending instructions back into the
instruction counter, and clear the interrupt flag. */
- qemu_icount -= (env->icount_decr.u16.low
- + env->icount_extra);
- env->icount_decr.u32 = 0;
- env->icount_extra = 0;
+ qemu_icount -= (cpu->icount_decr.u16.low + cpu->icount_extra);
+ cpu->icount_decr.u32 = 0;
+ cpu->icount_extra = 0;
}
return ret;
}
l = sizeof(buf);
if (l > size)
l = size;
- cpu_memory_rw_debug(cpu, addr, buf, l, 0);
+ if (cpu_memory_rw_debug(cpu, addr, buf, l, 0) != 0) {
+ error_setg(errp, "Invalid addr 0x%016" PRIx64 "specified", addr);
+ goto exit;
+ }
if (fwrite(buf, 1, l, f) != l) {
error_set(errp, QERR_IO_ERROR);
goto exit;
l = sizeof(buf);
if (l > size)
l = size;
- cpu_physical_memory_rw(addr, buf, l, 0);
+ cpu_physical_memory_read(addr, buf, l);
if (fwrite(buf, 1, l, f) != l) {
error_set(errp, QERR_IO_ERROR);
goto exit;
CPU_FOREACH(cs) {
X86CPU *cpu = X86_CPU(cs);
- CPUX86State *env = &cpu->env;
- if (!env->apic_state) {
+ if (!cpu->apic_state) {
cpu_interrupt(cs, CPU_INTERRUPT_NMI);
} else {
- apic_deliver_nmi(env->apic_state);
+ apic_deliver_nmi(cpu->apic_state);
}
}
#elif defined(TARGET_S390X)