current_machine is always set before accelerators are initialized, so use that instead of MACHINE(qdev_get_machine()). Signed-off-by: Claudio Fontana <cfontana@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
571 lines
16 KiB
C
571 lines
16 KiB
C
/*
|
|
* QEMU System Emulator
|
|
*
|
|
* Copyright (c) 2003-2008 Fabrice Bellard
|
|
* Copyright (c) 2014 Red Hat Inc.
|
|
*
|
|
* 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 "sysemu/tcg.h"
|
|
#include "sysemu/replay.h"
|
|
#include "qemu/main-loop.h"
|
|
#include "qemu/guest-random.h"
|
|
#include "exec/exec-all.h"
|
|
#include "hw/boards.h"
|
|
|
|
#include "tcg-cpus.h"
|
|
|
|
/* Kick all RR vCPUs */
|
|
static void qemu_cpu_kick_rr_cpus(void)
|
|
{
|
|
CPUState *cpu;
|
|
|
|
CPU_FOREACH(cpu) {
|
|
cpu_exit(cpu);
|
|
};
|
|
}
|
|
|
|
static void tcg_kick_vcpu_thread(CPUState *cpu)
|
|
{
|
|
if (qemu_tcg_mttcg_enabled()) {
|
|
cpu_exit(cpu);
|
|
} else {
|
|
qemu_cpu_kick_rr_cpus();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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 = qatomic_mb_read(&tcg_current_rr_cpu);
|
|
if (cpu) {
|
|
cpu_exit(cpu);
|
|
}
|
|
} while (cpu != qatomic_mb_read(&tcg_current_rr_cpu));
|
|
}
|
|
|
|
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);
|
|
}
|
|
}
|
|
|
|
static void qemu_tcg_destroy_vcpu(CPUState *cpu)
|
|
{
|
|
}
|
|
|
|
static void qemu_tcg_rr_wait_io_event(void)
|
|
{
|
|
CPUState *cpu;
|
|
|
|
while (all_cpu_threads_idle()) {
|
|
stop_tcg_kick_timer();
|
|
qemu_cond_wait_iothread(first_cpu->halt_cond);
|
|
}
|
|
|
|
start_tcg_kick_timer();
|
|
|
|
CPU_FOREACH(cpu) {
|
|
qemu_wait_io_event_common(cpu);
|
|
}
|
|
}
|
|
|
|
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 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 (icount_enabled()) {
|
|
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 (icount_enabled()) {
|
|
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 (icount_enabled()) {
|
|
/* Account for executed instructions */
|
|
icount_update(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
|
|
qatomic_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_thread_signal_destroyed(cpu);
|
|
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 *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->can_do_io = 1;
|
|
cpu_thread_signal_created(cpu);
|
|
qemu_guest_random_seed_thread_part2(cpu->random_seed);
|
|
|
|
/* wait for initial kick-off after machine start */
|
|
while (first_cpu->stopped) {
|
|
qemu_cond_wait_iothread(first_cpu->halt_cond);
|
|
|
|
/* 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. */
|
|
icount_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) {
|
|
|
|
qatomic_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 qatomic_mb_set because a spurious wakeup is okay. */
|
|
qatomic_set(&tcg_current_rr_cpu, NULL);
|
|
|
|
if (cpu && cpu->exit_request) {
|
|
qatomic_mb_set(&cpu->exit_request, 0);
|
|
}
|
|
|
|
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.
|
|
*/
|
|
qemu_notify_event();
|
|
}
|
|
|
|
qemu_tcg_rr_wait_io_event();
|
|
deal_with_unplugged_cpus();
|
|
}
|
|
|
|
rcu_unregister_thread();
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* 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 *tcg_cpu_thread_fn(void *arg)
|
|
{
|
|
CPUState *cpu = arg;
|
|
|
|
assert(tcg_enabled());
|
|
g_assert(!icount_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->can_do_io = 1;
|
|
current_cpu = cpu;
|
|
cpu_thread_signal_created(cpu);
|
|
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;
|
|
}
|
|
}
|
|
|
|
qatomic_mb_set(&cpu->exit_request, 0);
|
|
qemu_wait_io_event(cpu);
|
|
} while (!cpu->unplug || cpu_can_run(cpu));
|
|
|
|
qemu_tcg_destroy_vcpu(cpu);
|
|
cpu_thread_signal_destroyed(cpu);
|
|
qemu_mutex_unlock_iothread();
|
|
rcu_unregister_thread();
|
|
return NULL;
|
|
}
|
|
|
|
static void tcg_start_vcpu_thread(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();
|
|
parallel_cpus = qemu_tcg_mttcg_enabled() && current_machine->smp.max_cpus > 1;
|
|
}
|
|
|
|
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) */
|
|
snprintf(thread_name, VCPU_THREAD_NAME_SIZE, "CPU %d/TCG",
|
|
cpu->cpu_index);
|
|
|
|
qemu_thread_create(cpu->thread, thread_name, 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,
|
|
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 int64_t tcg_get_virtual_clock(void)
|
|
{
|
|
if (icount_enabled()) {
|
|
return icount_get();
|
|
}
|
|
return cpu_get_clock();
|
|
}
|
|
|
|
static int64_t tcg_get_elapsed_ticks(void)
|
|
{
|
|
if (icount_enabled()) {
|
|
return icount_get();
|
|
}
|
|
return cpu_get_ticks();
|
|
}
|
|
|
|
/* mask must never be zero, except for A20 change call */
|
|
static void tcg_handle_interrupt(CPUState *cpu, int mask)
|
|
{
|
|
int old_mask;
|
|
g_assert(qemu_mutex_iothread_locked());
|
|
|
|
old_mask = cpu->interrupt_request;
|
|
cpu->interrupt_request |= mask;
|
|
|
|
/*
|
|
* If called from iothread context, wake the target cpu in
|
|
* case its halted.
|
|
*/
|
|
if (!qemu_cpu_is_self(cpu)) {
|
|
qemu_cpu_kick(cpu);
|
|
} else {
|
|
qatomic_set(&cpu_neg(cpu)->icount_decr.u16.high, -1);
|
|
if (icount_enabled() &&
|
|
!cpu->can_do_io
|
|
&& (mask & ~old_mask) != 0) {
|
|
cpu_abort(cpu, "Raised interrupt while not in I/O function");
|
|
}
|
|
}
|
|
}
|
|
|
|
const CpusAccel tcg_cpus = {
|
|
.create_vcpu_thread = tcg_start_vcpu_thread,
|
|
.kick_vcpu_thread = tcg_kick_vcpu_thread,
|
|
|
|
.handle_interrupt = tcg_handle_interrupt,
|
|
|
|
.get_virtual_clock = tcg_get_virtual_clock,
|
|
.get_elapsed_ticks = tcg_get_elapsed_ticks,
|
|
};
|