diff options
Diffstat (limited to 'cpu-exec.c')
| -rw-r--r-- | cpu-exec.c | 89 |
1 files changed, 59 insertions, 30 deletions
@@ -29,6 +29,7 @@ #include "qemu/rcu.h" #include "exec/tb-hash.h" #include "exec/log.h" +#include "qemu/main-loop.h" #if defined(TARGET_I386) && !defined(CONFIG_USER_ONLY) #include "hw/i386/apic.h" #endif @@ -227,20 +228,43 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, static void cpu_exec_step(CPUState *cpu) { + CPUClass *cc = CPU_GET_CLASS(cpu); CPUArchState *env = (CPUArchState *)cpu->env_ptr; TranslationBlock *tb; target_ulong cs_base, pc; uint32_t flags; cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags); - tb = tb_gen_code(cpu, pc, cs_base, flags, - 1 | CF_NOCACHE | CF_IGNORE_ICOUNT); - tb->orig_tb = NULL; - /* execute the generated code */ - trace_exec_tb_nocache(tb, pc); - cpu_tb_exec(cpu, tb); - tb_phys_invalidate(tb, -1); - tb_free(tb); + if (sigsetjmp(cpu->jmp_env, 0) == 0) { + mmap_lock(); + tb_lock(); + tb = tb_gen_code(cpu, pc, cs_base, flags, + 1 | CF_NOCACHE | CF_IGNORE_ICOUNT); + tb->orig_tb = NULL; + tb_unlock(); + mmap_unlock(); + + cc->cpu_exec_enter(cpu); + /* execute the generated code */ + trace_exec_tb_nocache(tb, pc); + cpu_tb_exec(cpu, tb); + cc->cpu_exec_exit(cpu); + + tb_lock(); + tb_phys_invalidate(tb, -1); + tb_free(tb); + tb_unlock(); + } else { + /* We may have exited due to another problem here, so we need + * to reset any tb_locks we may have taken but didn't release. + * The mmap_lock is dropped by tb_gen_code if it runs out of + * memory. + */ +#ifndef CONFIG_SOFTMMU + tcg_debug_assert(!have_mmap_lock()); +#endif + tb_lock_reset(); + } } void cpu_exec_step_atomic(CPUState *cpu) @@ -384,12 +408,13 @@ static inline bool cpu_handle_halt(CPUState *cpu) if ((cpu->interrupt_request & CPU_INTERRUPT_POLL) && replay_interrupt()) { X86CPU *x86_cpu = X86_CPU(cpu); + qemu_mutex_lock_iothread(); apic_poll_irq(x86_cpu->apic_state); cpu_reset_interrupt(cpu, CPU_INTERRUPT_POLL); + qemu_mutex_unlock_iothread(); } #endif if (!cpu_has_work(cpu)) { - current_cpu = NULL; return true; } @@ -439,7 +464,9 @@ static inline bool cpu_handle_exception(CPUState *cpu, int *ret) #else if (replay_exception()) { CPUClass *cc = CPU_GET_CLASS(cpu); + qemu_mutex_lock_iothread(); cc->do_interrupt(cpu); + qemu_mutex_unlock_iothread(); cpu->exception_index = -1; } else if (!replay_has_interrupt()) { /* give a chance to iothread in replay mode */ @@ -465,9 +492,11 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, TranslationBlock **last_tb) { CPUClass *cc = CPU_GET_CLASS(cpu); - int interrupt_request = cpu->interrupt_request; - if (unlikely(interrupt_request)) { + if (unlikely(atomic_read(&cpu->interrupt_request))) { + int interrupt_request; + qemu_mutex_lock_iothread(); + interrupt_request = cpu->interrupt_request; if (unlikely(cpu->singlestep_enabled & SSTEP_NOIRQ)) { /* Mask out external interrupts for this step. */ interrupt_request &= ~CPU_INTERRUPT_SSTEP_MASK; @@ -475,6 +504,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, if (interrupt_request & CPU_INTERRUPT_DEBUG) { cpu->interrupt_request &= ~CPU_INTERRUPT_DEBUG; cpu->exception_index = EXCP_DEBUG; + qemu_mutex_unlock_iothread(); return true; } if (replay_mode == REPLAY_MODE_PLAY && !replay_has_interrupt()) { @@ -484,6 +514,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, cpu->interrupt_request &= ~CPU_INTERRUPT_HALT; cpu->halted = 1; cpu->exception_index = EXCP_HLT; + qemu_mutex_unlock_iothread(); return true; } #if defined(TARGET_I386) @@ -494,12 +525,14 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, cpu_svm_check_intercept_param(env, SVM_EXIT_INIT, 0, 0); do_cpu_init(x86_cpu); cpu->exception_index = EXCP_HALTED; + qemu_mutex_unlock_iothread(); return true; } #else else if (interrupt_request & CPU_INTERRUPT_RESET) { replay_interrupt(); cpu_reset(cpu); + qemu_mutex_unlock_iothread(); return true; } #endif @@ -522,7 +555,12 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, the program flow was changed */ *last_tb = NULL; } + + /* If we exit via cpu_loop_exit/longjmp it is reset in cpu_exec */ + qemu_mutex_unlock_iothread(); } + + if (unlikely(atomic_read(&cpu->exit_request) || replay_has_interrupt())) { atomic_set(&cpu->exit_request, 0); cpu->exception_index = EXCP_INTERRUPT; @@ -548,15 +586,13 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb, *tb_exit = ret & TB_EXIT_MASK; switch (*tb_exit) { case TB_EXIT_REQUESTED: - /* Something asked us to stop executing - * chained TBs; just continue round the main - * loop. Whatever requested the exit will also - * have set something else (eg exit_request or - * interrupt_request) which we will handle - * next time around the loop. But we need to - * ensure the zeroing of tcg_exit_req (see cpu_tb_exec) - * comes before the next read of cpu->exit_request - * or cpu->interrupt_request. + /* Something asked us to stop executing chained TBs; just + * continue round the main loop. Whatever requested the exit + * will also have set something else (eg interrupt_request) + * which we will handle next time around the loop. But we + * need to ensure the tcg_exit_req read in generated code + * comes before the next read of cpu->exit_request or + * cpu->interrupt_request. */ smp_mb(); *last_tb = NULL; @@ -608,13 +644,8 @@ int cpu_exec(CPUState *cpu) return EXCP_HALTED; } - atomic_mb_set(&tcg_current_cpu, cpu); rcu_read_lock(); - if (unlikely(atomic_mb_read(&exit_request))) { - cpu->exit_request = 1; - } - cc->cpu_exec_enter(cpu); /* Calculate difference between guest clock and host clock. @@ -640,6 +671,9 @@ int cpu_exec(CPUState *cpu) #endif /* buggy compiler */ cpu->can_do_io = 1; tb_lock_reset(); + if (qemu_mutex_iothread_locked()) { + qemu_mutex_unlock_iothread(); + } } /* if an exception is pending, we execute it here */ @@ -659,10 +693,5 @@ int cpu_exec(CPUState *cpu) cc->cpu_exec_exit(cpu); rcu_read_unlock(); - /* fail safe : never use current_cpu outside cpu_exec() */ - current_cpu = NULL; - - /* Does not need atomic_mb_set because a spurious wakeup is okay. */ - atomic_set(&tcg_current_cpu, NULL); return ret; } |