diff options
Diffstat (limited to 'accel/tcg/tcg-cpus-mttcg.c')
-rw-r--r-- | accel/tcg/tcg-cpus-mttcg.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/accel/tcg/tcg-cpus-mttcg.c b/accel/tcg/tcg-cpus-mttcg.c new file mode 100644 index 0000000000..dac724fc85 --- /dev/null +++ b/accel/tcg/tcg-cpus-mttcg.c @@ -0,0 +1,117 @@ +/* + * 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 "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" +#include "tcg-cpus-mttcg.h" + +/* + * 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. + */ + +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); + qemu_mutex_unlock_iothread(); + rcu_unregister_thread(); + return NULL; +} + +static void mttcg_kick_vcpu_thread(CPUState *cpu) +{ + cpu_exit(cpu); +} + +const CpusAccel tcg_cpus_mttcg = { + .create_vcpu_thread = tcg_start_vcpu_thread, + .kick_vcpu_thread = mttcg_kick_vcpu_thread, + + .handle_interrupt = tcg_handle_interrupt, +}; |