| /* |
| * QEMU TCG Multi Threaded vCPUs implementation |
| * |
| * 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 "sysemu/tcg.h" |
| #include "sysemu/replay.h" |
| #include "sysemu/cpu-timers.h" |
| #include "qemu/main-loop.h" |
| #include "qemu/notify.h" |
| #include "qemu/guest-random.h" |
| #include "exec/exec-all.h" |
| #include "hw/boards.h" |
| |
| #include "tcg-accel-ops.h" |
| #include "tcg-accel-ops-mttcg.h" |
| |
| typedef struct MttcgForceRcuNotifier { |
| Notifier notifier; |
| CPUState *cpu; |
| } MttcgForceRcuNotifier; |
| |
| static void do_nothing(CPUState *cpu, run_on_cpu_data d) |
| { |
| } |
| |
| static void mttcg_force_rcu(Notifier *notify, void *data) |
| { |
| CPUState *cpu = container_of(notify, MttcgForceRcuNotifier, notifier)->cpu; |
| |
| /* |
| * Called with rcu_registry_lock held, using async_run_on_cpu() ensures |
| * that there are no deadlocks. |
| */ |
| async_run_on_cpu(cpu, do_nothing, RUN_ON_CPU_NULL); |
| } |
| |
| /* |
| * 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 *mttcg_cpu_thread_fn(void *arg) |
| { |
| MttcgForceRcuNotifier force_rcu; |
| CPUState *cpu = arg; |
| |
| assert(tcg_enabled()); |
| g_assert(!icount_enabled()); |
| |
| tcg_cpu_init_cflags(cpu, current_machine->smp.max_cpus > 1); |
| |
| rcu_register_thread(); |
| force_rcu.notifier.notify = mttcg_force_rcu; |
| force_rcu.cpu = cpu; |
| rcu_add_force_rcu_notifier(&force_rcu.notifier); |
| 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_cpus_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)); |
| |
| tcg_cpus_destroy(cpu); |
| qemu_mutex_unlock_iothread(); |
| rcu_remove_force_rcu_notifier(&force_rcu.notifier); |
| rcu_unregister_thread(); |
| return NULL; |
| } |
| |
| void mttcg_kick_vcpu_thread(CPUState *cpu) |
| { |
| cpu_exit(cpu); |
| } |
| |
| void mttcg_start_vcpu_thread(CPUState *cpu) |
| { |
| char thread_name[VCPU_THREAD_NAME_SIZE]; |
| |
| cpu->thread = g_new0(QemuThread, 1); |
| cpu->halt_cond = g_malloc0(sizeof(QemuCond)); |
| qemu_cond_init(cpu->halt_cond); |
| |
| /* 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, mttcg_cpu_thread_fn, |
| cpu, QEMU_THREAD_JOINABLE); |
| |
| #ifdef _WIN32 |
| cpu->hThread = qemu_thread_get_handle(cpu->thread); |
| #endif |
| } |