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cpu-timers, icount: new modules

Browse source 
refactoring of cpus.c continues with cpu timer state extraction.

cpu-timers: responsible for the softmmu cpu timers state,
            including cpu clocks and ticks.

icount: counts the TCG instructions executed. As such it is specific to
the TCG accelerator. Therefore, it is built only under CONFIG_TCG.

One complication is due to qtest, which uses an icount field to warp time
as part of qtest (qtest_clock_warp).

In order to solve this problem, provide a separate counter for qtest.

This requires fixing assumptions scattered in the code that
qtest_enabled() implies icount_enabled(), checking each specific case.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[remove redundant initialization with qemu_spice_init]
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
[fix lingering calls to icount_get]
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Claudio Fontana 2020-08-19 13:17:19 +02:00 • committed by Paolo Bonzini
parent 0ac0b47c44
commit 740b175973
37 changed files with 1128 additions and 843 deletions
Download patch file Download diff file Expand all files Collapse all files

744
softmmu/cpus.c
View file

@ -58,11 +58,10 @@
#include "hw/nmi.h"
#include "sysemu/replay.h"
#include "sysemu/runstate.h"
#include "sysemu/cpu-timers.h"
#include "hw/boards.h"
#include "hw/hw.h"
#include "sysemu/cpu-throttle.h"
#ifdef CONFIG_LINUX
#include <sys/prctl.h>
@ -83,9 +82,6 @@
static QemuMutex qemu_global_mutex;
int64_t max_delay;
int64_t max_advance;
bool cpu_is_stopped(CPUState *cpu)
{
return cpu->stopped || !runstate_is_running();
@ -116,7 +112,7 @@ static bool cpu_thread_is_idle(CPUState *cpu)
return true;
}
static bool all_cpu_threads_idle(void)
bool all_cpu_threads_idle(void)
{
CPUState *cpu;
@ -128,688 +124,9 @@ static bool all_cpu_threads_idle(void)
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;
qatomic_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 qatomic_read_i64(&timers_state.qemu_icount);
}
static int64_t cpu_get_icount_locked(void)
{
int64_t icount = cpu_get_icount_raw_locked();
return qatomic_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 << qatomic_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. */
qatomic_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. */
qatomic_set(&timers_state.icount_time_shift,
timers_state.icount_time_shift + 1);
}
last_delta = delta;
qatomic_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 = qatomic_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);
}
qatomic_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);
qatomic_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);
qatomic_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
}
};
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);
cpu_throttle_init();
}
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
*
@ -854,35 +171,6 @@ static void qemu_cpu_kick_rr_cpus(void)
};
}
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());
@ -1288,7 +576,7 @@ static void notify_aio_contexts(void)
static void handle_icount_deadline(void)
{
assert(qemu_in_vcpu_thread());
if (use_icount) {
if (icount_enabled()) {
int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
QEMU_TIMER_ATTR_ALL);
@ -1300,7 +588,7 @@ static void handle_icount_deadline(void)
static void prepare_icount_for_run(CPUState *cpu)
{
if (use_icount) {
if (icount_enabled()) {
int insns_left;
/* These should always be cleared by process_icount_data after
@ -1325,7 +613,7 @@ static void prepare_icount_for_run(CPUState *cpu)
static void process_icount_data(CPUState *cpu)
{
if (use_icount) {
if (icount_enabled()) {
/* Account for executed instructions */
cpu_update_icount(cpu);
@ -1486,7 +774,7 @@ static void *qemu_tcg_rr_cpu_thread_fn(void *arg)
qatomic_mb_set(&cpu->exit_request, 0);
}
if (use_icount && all_cpu_threads_idle()) {
if (icount_enabled() && 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.
@ -1639,7 +927,7 @@ static void *qemu_tcg_cpu_thread_fn(void *arg)
CPUState *cpu = arg;
assert(tcg_enabled());
g_assert(!use_icount);
g_assert(!icount_enabled());
rcu_register_thread();
tcg_register_thread();
@ -2227,21 +1515,3 @@ 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");
}
}