qemu/cpu-exec-common.c

82 lines
2.4 KiB
C

/*
* emulator main execution loop
*
* Copyright (c) 2003-2005 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include "cpu.h"
#include "sysemu/cpus.h"
#include "exec/memory-internal.h"
bool exit_request;
CPUState *tcg_current_cpu;
/* exit the current TB from a signal handler. The host registers are
restored in a state compatible with the CPU emulator
*/
#if defined(CONFIG_SOFTMMU)
void cpu_resume_from_signal(CPUState *cpu, void *puc)
{
/* XXX: restore cpu registers saved in host registers */
cpu->exception_index = -1;
siglongjmp(cpu->jmp_env, 1);
}
void cpu_reload_memory_map(CPUState *cpu)
{
AddressSpaceDispatch *d;
if (qemu_in_vcpu_thread()) {
/* Do not let the guest prolong the critical section as much as it
* as it desires.
*
* Currently, this is prevented by the I/O thread's periodinc kicking
* of the VCPU thread (iothread_requesting_mutex, qemu_cpu_kick_thread)
* but this will go away once TCG's execution moves out of the global
* mutex.
*
* This pair matches cpu_exec's rcu_read_lock()/rcu_read_unlock(), which
* only protects cpu->as->dispatch. Since we reload it below, we can
* split the critical section.
*/
rcu_read_unlock();
rcu_read_lock();
}
/* The CPU and TLB are protected by the iothread lock. */
d = atomic_rcu_read(&cpu->as->dispatch);
cpu->memory_dispatch = d;
tlb_flush(cpu, 1);
}
#endif
void cpu_loop_exit(CPUState *cpu)
{
cpu->current_tb = NULL;
siglongjmp(cpu->jmp_env, 1);
}
void cpu_loop_exit_restore(CPUState *cpu, uintptr_t pc)
{
if (pc) {
cpu_restore_state(cpu, pc);
}
cpu->current_tb = NULL;
siglongjmp(cpu->jmp_env, 1);
}