qemu/accel/dummy-cpus.c
Richard Henderson 464dacf609 accel/tcg: Move can_do_io to CPUNegativeOffsetState
Minimize the displacement to can_do_io, since it may
be touched at the start of each TranslationBlock.
It fits into other padding within the substructure.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-03 08:01:02 -07:00

83 lines
1.9 KiB
C

/*
* Dummy cpu thread code
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qemu/rcu.h"
#include "sysemu/cpus.h"
#include "qemu/guest-random.h"
#include "qemu/main-loop.h"
#include "hw/core/cpu.h"
static void *dummy_cpu_thread_fn(void *arg)
{
CPUState *cpu = arg;
rcu_register_thread();
qemu_mutex_lock_iothread();
qemu_thread_get_self(cpu->thread);
cpu->thread_id = qemu_get_thread_id();
cpu->neg.can_do_io = true;
current_cpu = cpu;
#ifndef _WIN32
sigset_t waitset;
int r;
sigemptyset(&waitset);
sigaddset(&waitset, SIG_IPI);
#endif
/* signal CPU creation */
cpu_thread_signal_created(cpu);
qemu_guest_random_seed_thread_part2(cpu->random_seed);
do {
qemu_mutex_unlock_iothread();
#ifndef _WIN32
do {
int sig;
r = sigwait(&waitset, &sig);
} while (r == -1 && (errno == EAGAIN || errno == EINTR));
if (r == -1) {
perror("sigwait");
exit(1);
}
#else
qemu_sem_wait(&cpu->sem);
#endif
qemu_mutex_lock_iothread();
qemu_wait_io_event(cpu);
} while (!cpu->unplug);
qemu_mutex_unlock_iothread();
rcu_unregister_thread();
return NULL;
}
void dummy_start_vcpu_thread(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, dummy_cpu_thread_fn, cpu,
QEMU_THREAD_JOINABLE);
#ifdef _WIN32
qemu_sem_init(&cpu->sem, 0);
#endif
}