diff options
Diffstat (limited to 'system/cpus.c')
| -rw-r--r-- | system/cpus.c | 822 |
1 files changed, 822 insertions, 0 deletions
diff --git a/system/cpus.c b/system/cpus.c new file mode 100644 index 0000000..0848e0d --- /dev/null +++ b/system/cpus.c @@ -0,0 +1,822 @@ +/* + * QEMU System Emulator + * + * Copyright (c) 2003-2008 Fabrice Bellard + * + * 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 "monitor/monitor.h" +#include "qemu/coroutine-tls.h" +#include "qapi/error.h" +#include "qapi/qapi-commands-machine.h" +#include "qapi/qapi-commands-misc.h" +#include "qapi/qapi-events-run-state.h" +#include "qapi/qmp/qerror.h" +#include "exec/gdbstub.h" +#include "sysemu/hw_accel.h" +#include "exec/cpu-common.h" +#include "qemu/thread.h" +#include "qemu/main-loop.h" +#include "qemu/plugin.h" +#include "sysemu/cpus.h" +#include "qemu/guest-random.h" +#include "hw/nmi.h" +#include "sysemu/replay.h" +#include "sysemu/runstate.h" +#include "sysemu/cpu-timers.h" +#include "sysemu/whpx.h" +#include "hw/boards.h" +#include "hw/hw.h" +#include "trace.h" + +#ifdef CONFIG_LINUX + +#include <sys/prctl.h> + +#ifndef PR_MCE_KILL +#define PR_MCE_KILL 33 +#endif + +#ifndef PR_MCE_KILL_SET +#define PR_MCE_KILL_SET 1 +#endif + +#ifndef PR_MCE_KILL_EARLY +#define PR_MCE_KILL_EARLY 1 +#endif + +#endif /* CONFIG_LINUX */ + +static QemuMutex qemu_global_mutex; + +/* + * The chosen accelerator is supposed to register this. + */ +static const AccelOpsClass *cpus_accel; + +bool cpu_is_stopped(CPUState *cpu) +{ + return cpu->stopped || !runstate_is_running(); +} + +bool cpu_work_list_empty(CPUState *cpu) +{ + return QSIMPLEQ_EMPTY_ATOMIC(&cpu->work_list); +} + +bool cpu_thread_is_idle(CPUState *cpu) +{ + if (cpu->stop || !cpu_work_list_empty(cpu)) { + return false; + } + if (cpu_is_stopped(cpu)) { + return true; + } + if (!cpu->halted || cpu_has_work(cpu)) { + return false; + } + if (cpus_accel->cpu_thread_is_idle) { + return cpus_accel->cpu_thread_is_idle(cpu); + } + return true; +} + +bool all_cpu_threads_idle(void) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + if (!cpu_thread_is_idle(cpu)) { + return false; + } + } + return true; +} + +/***********************************************************/ +void hw_error(const char *fmt, ...) +{ + va_list ap; + CPUState *cpu; + + va_start(ap, fmt); + fprintf(stderr, "qemu: hardware error: "); + vfprintf(stderr, fmt, ap); + fprintf(stderr, "\n"); + CPU_FOREACH(cpu) { + fprintf(stderr, "CPU #%d:\n", cpu->cpu_index); + cpu_dump_state(cpu, stderr, CPU_DUMP_FPU); + } + va_end(ap); + abort(); +} + +void cpu_synchronize_all_states(void) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + cpu_synchronize_state(cpu); + } +} + +void cpu_synchronize_all_post_reset(void) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + cpu_synchronize_post_reset(cpu); + } +} + +void cpu_synchronize_all_post_init(void) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + cpu_synchronize_post_init(cpu); + } +} + +void cpu_synchronize_all_pre_loadvm(void) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + cpu_synchronize_pre_loadvm(cpu); + } +} + +void cpu_synchronize_state(CPUState *cpu) +{ + if (cpus_accel->synchronize_state) { + cpus_accel->synchronize_state(cpu); + } +} + +void cpu_synchronize_post_reset(CPUState *cpu) +{ + if (cpus_accel->synchronize_post_reset) { + cpus_accel->synchronize_post_reset(cpu); + } +} + +void cpu_synchronize_post_init(CPUState *cpu) +{ + if (cpus_accel->synchronize_post_init) { + cpus_accel->synchronize_post_init(cpu); + } +} + +void cpu_synchronize_pre_loadvm(CPUState *cpu) +{ + if (cpus_accel->synchronize_pre_loadvm) { + cpus_accel->synchronize_pre_loadvm(cpu); + } +} + +bool cpus_are_resettable(void) +{ + if (cpus_accel->cpus_are_resettable) { + return cpus_accel->cpus_are_resettable(); + } + return true; +} + +int64_t cpus_get_virtual_clock(void) +{ + /* + * XXX + * + * need to check that cpus_accel is not NULL, because qcow2 calls + * qemu_get_clock_ns(CLOCK_VIRTUAL) without any accel initialized and + * with ticks disabled in some io-tests: + * 030 040 041 060 099 120 127 140 156 161 172 181 191 192 195 203 229 249 256 267 + * + * is this expected? + * + * XXX + */ + if (cpus_accel && cpus_accel->get_virtual_clock) { + return cpus_accel->get_virtual_clock(); + } + return cpu_get_clock(); +} + +/* + * return the time elapsed in VM between vm_start and vm_stop. Unless + * icount is active, cpus_get_elapsed_ticks() uses units of the host CPU cycle + * counter. + */ +int64_t cpus_get_elapsed_ticks(void) +{ + if (cpus_accel->get_elapsed_ticks) { + return cpus_accel->get_elapsed_ticks(); + } + return cpu_get_ticks(); +} + +static void generic_handle_interrupt(CPUState *cpu, int mask) +{ + cpu->interrupt_request |= mask; + + if (!qemu_cpu_is_self(cpu)) { + qemu_cpu_kick(cpu); + } +} + +void cpu_interrupt(CPUState *cpu, int mask) +{ + if (cpus_accel->handle_interrupt) { + cpus_accel->handle_interrupt(cpu, mask); + } else { + generic_handle_interrupt(cpu, mask); + } +} + +static int do_vm_stop(RunState state, bool send_stop) +{ + int ret = 0; + + if (runstate_is_running()) { + runstate_set(state); + cpu_disable_ticks(); + pause_all_vcpus(); + vm_state_notify(0, state); + if (send_stop) { + qapi_event_send_stop(); + } + } + + bdrv_drain_all(); + ret = bdrv_flush_all(); + trace_vm_stop_flush_all(ret); + + return ret; +} + +/* Special vm_stop() variant for terminating the process. Historically clients + * did not expect a QMP STOP event and so we need to retain compatibility. + */ +int vm_shutdown(void) +{ + return do_vm_stop(RUN_STATE_SHUTDOWN, false); +} + +bool cpu_can_run(CPUState *cpu) +{ + if (cpu->stop) { + return false; + } + if (cpu_is_stopped(cpu)) { + return false; + } + return true; +} + +void cpu_handle_guest_debug(CPUState *cpu) +{ + if (replay_running_debug()) { + if (!cpu->singlestep_enabled) { + /* + * Report about the breakpoint and + * make a single step to skip it + */ + replay_breakpoint(); + cpu_single_step(cpu, SSTEP_ENABLE); + } else { + cpu_single_step(cpu, 0); + } + } else { + gdb_set_stop_cpu(cpu); + qemu_system_debug_request(); + cpu->stopped = true; + } +} + +#ifdef CONFIG_LINUX +static void sigbus_reraise(void) +{ + sigset_t set; + struct sigaction action; + + memset(&action, 0, sizeof(action)); + action.sa_handler = SIG_DFL; + if (!sigaction(SIGBUS, &action, NULL)) { + raise(SIGBUS); + sigemptyset(&set); + sigaddset(&set, SIGBUS); + pthread_sigmask(SIG_UNBLOCK, &set, NULL); + } + perror("Failed to re-raise SIGBUS!"); + abort(); +} + +static void sigbus_handler(int n, siginfo_t *siginfo, void *ctx) +{ + if (siginfo->si_code != BUS_MCEERR_AO && siginfo->si_code != BUS_MCEERR_AR) { + sigbus_reraise(); + } + + if (current_cpu) { + /* Called asynchronously in VCPU thread. */ + if (kvm_on_sigbus_vcpu(current_cpu, siginfo->si_code, siginfo->si_addr)) { + sigbus_reraise(); + } + } else { + /* Called synchronously (via signalfd) in main thread. */ + if (kvm_on_sigbus(siginfo->si_code, siginfo->si_addr)) { + sigbus_reraise(); + } + } +} + +static void qemu_init_sigbus(void) +{ + struct sigaction action; + + /* + * ALERT: when modifying this, take care that SIGBUS forwarding in + * qemu_prealloc_mem() will continue working as expected. + */ + memset(&action, 0, sizeof(action)); + action.sa_flags = SA_SIGINFO; + action.sa_sigaction = sigbus_handler; + sigaction(SIGBUS, &action, NULL); + + prctl(PR_MCE_KILL, PR_MCE_KILL_SET, PR_MCE_KILL_EARLY, 0, 0); +} +#else /* !CONFIG_LINUX */ +static void qemu_init_sigbus(void) +{ +} +#endif /* !CONFIG_LINUX */ + +static QemuThread io_thread; + +/* cpu creation */ +static QemuCond qemu_cpu_cond; +/* system init */ +static QemuCond qemu_pause_cond; + +void qemu_init_cpu_loop(void) +{ + qemu_init_sigbus(); + qemu_cond_init(&qemu_cpu_cond); + qemu_cond_init(&qemu_pause_cond); + qemu_mutex_init(&qemu_global_mutex); + + qemu_thread_get_self(&io_thread); +} + +void run_on_cpu(CPUState *cpu, run_on_cpu_func func, run_on_cpu_data data) +{ + do_run_on_cpu(cpu, func, data, &qemu_global_mutex); +} + +static void qemu_cpu_stop(CPUState *cpu, bool exit) +{ + g_assert(qemu_cpu_is_self(cpu)); + cpu->stop = false; + cpu->stopped = true; + if (exit) { + cpu_exit(cpu); + } + qemu_cond_broadcast(&qemu_pause_cond); +} + +void qemu_wait_io_event_common(CPUState *cpu) +{ + qatomic_set_mb(&cpu->thread_kicked, false); + if (cpu->stop) { + qemu_cpu_stop(cpu, false); + } + process_queued_cpu_work(cpu); +} + +void qemu_wait_io_event(CPUState *cpu) +{ + bool slept = false; + + while (cpu_thread_is_idle(cpu)) { + if (!slept) { + slept = true; + qemu_plugin_vcpu_idle_cb(cpu); + } + qemu_cond_wait(cpu->halt_cond, &qemu_global_mutex); + } + if (slept) { + qemu_plugin_vcpu_resume_cb(cpu); + } + + qemu_wait_io_event_common(cpu); +} + +void cpus_kick_thread(CPUState *cpu) +{ + if (cpu->thread_kicked) { + return; + } + cpu->thread_kicked = true; + +#ifndef _WIN32 + int err = pthread_kill(cpu->thread->thread, SIG_IPI); + if (err && err != ESRCH) { + fprintf(stderr, "qemu:%s: %s", __func__, strerror(err)); + exit(1); + } +#else + qemu_sem_post(&cpu->sem); +#endif +} + +void qemu_cpu_kick(CPUState *cpu) +{ + qemu_cond_broadcast(cpu->halt_cond); + if (cpus_accel->kick_vcpu_thread) { + cpus_accel->kick_vcpu_thread(cpu); + } else { /* default */ + cpus_kick_thread(cpu); + } +} + +void qemu_cpu_kick_self(void) +{ + assert(current_cpu); + cpus_kick_thread(current_cpu); +} + +bool qemu_cpu_is_self(CPUState *cpu) +{ + return qemu_thread_is_self(cpu->thread); +} + +bool qemu_in_vcpu_thread(void) +{ + return current_cpu && qemu_cpu_is_self(current_cpu); +} + +QEMU_DEFINE_STATIC_CO_TLS(bool, iothread_locked) + +bool qemu_mutex_iothread_locked(void) +{ + return get_iothread_locked(); +} + +bool qemu_in_main_thread(void) +{ + return qemu_mutex_iothread_locked(); +} + +/* + * The BQL is taken from so many places that it is worth profiling the + * callers directly, instead of funneling them all through a single function. + */ +void qemu_mutex_lock_iothread_impl(const char *file, int line) +{ + QemuMutexLockFunc bql_lock = qatomic_read(&qemu_bql_mutex_lock_func); + + g_assert(!qemu_mutex_iothread_locked()); + bql_lock(&qemu_global_mutex, file, line); + set_iothread_locked(true); +} + +void qemu_mutex_unlock_iothread(void) +{ + g_assert(qemu_mutex_iothread_locked()); + set_iothread_locked(false); + qemu_mutex_unlock(&qemu_global_mutex); +} + +void qemu_cond_wait_iothread(QemuCond *cond) +{ + qemu_cond_wait(cond, &qemu_global_mutex); +} + +void qemu_cond_timedwait_iothread(QemuCond *cond, int ms) +{ + qemu_cond_timedwait(cond, &qemu_global_mutex, ms); +} + +/* signal CPU creation */ +void cpu_thread_signal_created(CPUState *cpu) +{ + cpu->created = true; + qemu_cond_signal(&qemu_cpu_cond); +} + +/* signal CPU destruction */ +void cpu_thread_signal_destroyed(CPUState *cpu) +{ + cpu->created = false; + qemu_cond_signal(&qemu_cpu_cond); +} + + +static bool all_vcpus_paused(void) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + if (!cpu->stopped) { + return false; + } + } + + return true; +} + +void pause_all_vcpus(void) +{ + CPUState *cpu; + + qemu_clock_enable(QEMU_CLOCK_VIRTUAL, false); + CPU_FOREACH(cpu) { + if (qemu_cpu_is_self(cpu)) { + qemu_cpu_stop(cpu, true); + } else { + cpu->stop = true; + qemu_cpu_kick(cpu); + } + } + + /* We need to drop the replay_lock so any vCPU threads woken up + * can finish their replay tasks + */ + replay_mutex_unlock(); + + while (!all_vcpus_paused()) { + qemu_cond_wait(&qemu_pause_cond, &qemu_global_mutex); + CPU_FOREACH(cpu) { + qemu_cpu_kick(cpu); + } + } + + qemu_mutex_unlock_iothread(); + replay_mutex_lock(); + qemu_mutex_lock_iothread(); +} + +void cpu_resume(CPUState *cpu) +{ + cpu->stop = false; + cpu->stopped = false; + qemu_cpu_kick(cpu); +} + +void resume_all_vcpus(void) +{ + CPUState *cpu; + + if (!runstate_is_running()) { + return; + } + + qemu_clock_enable(QEMU_CLOCK_VIRTUAL, true); + CPU_FOREACH(cpu) { + cpu_resume(cpu); + } +} + +void cpu_remove_sync(CPUState *cpu) +{ + cpu->stop = true; + cpu->unplug = true; + qemu_cpu_kick(cpu); + qemu_mutex_unlock_iothread(); + qemu_thread_join(cpu->thread); + qemu_mutex_lock_iothread(); +} + +void cpus_register_accel(const AccelOpsClass *ops) +{ + assert(ops != NULL); + assert(ops->create_vcpu_thread != NULL); /* mandatory */ + cpus_accel = ops; +} + +const AccelOpsClass *cpus_get_accel(void) +{ + /* broken if we call this early */ + assert(cpus_accel); + return cpus_accel; +} + +void qemu_init_vcpu(CPUState *cpu) +{ + MachineState *ms = MACHINE(qdev_get_machine()); + + cpu->nr_cores = ms->smp.cores; + cpu->nr_threads = ms->smp.threads; + cpu->stopped = true; + cpu->random_seed = qemu_guest_random_seed_thread_part1(); + + if (!cpu->as) { + /* If the target cpu hasn't set up any address spaces itself, + * give it the default one. + */ + cpu->num_ases = 1; + cpu_address_space_init(cpu, 0, "cpu-memory", cpu->memory); + } + + /* accelerators all implement the AccelOpsClass */ + g_assert(cpus_accel != NULL && cpus_accel->create_vcpu_thread != NULL); + cpus_accel->create_vcpu_thread(cpu); + + while (!cpu->created) { + qemu_cond_wait(&qemu_cpu_cond, &qemu_global_mutex); + } +} + +void cpu_stop_current(void) +{ + if (current_cpu) { + current_cpu->stop = true; + cpu_exit(current_cpu); + } +} + +int vm_stop(RunState state) +{ + if (qemu_in_vcpu_thread()) { + qemu_system_vmstop_request_prepare(); + qemu_system_vmstop_request(state); + /* + * FIXME: should not return to device code in case + * vm_stop() has been requested. + */ + cpu_stop_current(); + return 0; + } + + return do_vm_stop(state, true); +} + +/** + * Prepare for (re)starting the VM. + * Returns -1 if the vCPUs are not to be restarted (e.g. if they are already + * running or in case of an error condition), 0 otherwise. + */ +int vm_prepare_start(bool step_pending) +{ + RunState requested; + + qemu_vmstop_requested(&requested); + if (runstate_is_running() && requested == RUN_STATE__MAX) { + return -1; + } + + /* Ensure that a STOP/RESUME pair of events is emitted if a + * vmstop request was pending. The BLOCK_IO_ERROR event, for + * example, according to documentation is always followed by + * the STOP event. + */ + if (runstate_is_running()) { + qapi_event_send_stop(); + qapi_event_send_resume(); + return -1; + } + + /* + * WHPX accelerator needs to know whether we are going to step + * any CPUs, before starting the first one. + */ + if (cpus_accel->synchronize_pre_resume) { + cpus_accel->synchronize_pre_resume(step_pending); + } + + /* We are sending this now, but the CPUs will be resumed shortly later */ + qapi_event_send_resume(); + + cpu_enable_ticks(); + runstate_set(RUN_STATE_RUNNING); + vm_state_notify(1, RUN_STATE_RUNNING); + return 0; +} + +void vm_start(void) +{ + if (!vm_prepare_start(false)) { + resume_all_vcpus(); + } +} + +/* does a state transition even if the VM is already stopped, + current state is forgotten forever */ +int vm_stop_force_state(RunState state) +{ + if (runstate_is_running()) { + return vm_stop(state); + } else { + int ret; + runstate_set(state); + + bdrv_drain_all(); + /* Make sure to return an error if the flush in a previous vm_stop() + * failed. */ + ret = bdrv_flush_all(); + trace_vm_stop_flush_all(ret); + return ret; + } +} + +void qmp_memsave(int64_t addr, int64_t size, const char *filename, + bool has_cpu, int64_t cpu_index, Error **errp) +{ + FILE *f; + uint32_t l; + CPUState *cpu; + uint8_t buf[1024]; + int64_t orig_addr = addr, orig_size = size; + + if (!has_cpu) { + cpu_index = 0; + } + + cpu = qemu_get_cpu(cpu_index); + if (cpu == NULL) { + error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cpu-index", + "a CPU number"); + return; + } + + f = fopen(filename, "wb"); + if (!f) { + error_setg_file_open(errp, errno, filename); + return; + } + + while (size != 0) { + l = sizeof(buf); + if (l > size) + l = size; + if (cpu_memory_rw_debug(cpu, addr, buf, l, 0) != 0) { + error_setg(errp, "Invalid addr 0x%016" PRIx64 "/size %" PRId64 + " specified", orig_addr, orig_size); + goto exit; + } + if (fwrite(buf, 1, l, f) != l) { + error_setg(errp, QERR_IO_ERROR); + goto exit; + } + addr += l; + size -= l; + } + +exit: + fclose(f); +} + +void qmp_pmemsave(int64_t addr, int64_t size, const char *filename, + Error **errp) +{ + FILE *f; + uint32_t l; + uint8_t buf[1024]; + + f = fopen(filename, "wb"); + if (!f) { + error_setg_file_open(errp, errno, filename); + return; + } + + while (size != 0) { + l = sizeof(buf); + if (l > size) + l = size; + cpu_physical_memory_read(addr, buf, l); + if (fwrite(buf, 1, l, f) != l) { + error_setg(errp, QERR_IO_ERROR); + goto exit; + } + addr += l; + size -= l; + } + +exit: + fclose(f); +} + +void qmp_inject_nmi(Error **errp) +{ + nmi_monitor_handle(monitor_get_cpu_index(monitor_cur()), errp); +} + |