diff options
Diffstat (limited to 'accel')
-rw-r--r-- | accel/tcg/cpu-exec.c | 95 |
1 files changed, 54 insertions, 41 deletions
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index 0473055a08..f3de96f346 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -470,48 +470,51 @@ static inline void cpu_handle_debug_exception(CPUState *cpu) static inline bool cpu_handle_exception(CPUState *cpu, int *ret) { - if (cpu->exception_index >= 0) { - if (cpu->exception_index >= EXCP_INTERRUPT) { - /* exit request from the cpu execution loop */ - *ret = cpu->exception_index; - if (*ret == EXCP_DEBUG) { - cpu_handle_debug_exception(cpu); - } - cpu->exception_index = -1; - return true; - } else { + if (cpu->exception_index < 0) { +#ifndef CONFIG_USER_ONLY + if (replay_has_exception() + && cpu->icount_decr.u16.low + cpu->icount_extra == 0) { + /* try to cause an exception pending in the log */ + cpu_exec_nocache(cpu, 1, tb_find(cpu, NULL, 0, curr_cflags()), true); + } +#endif + if (cpu->exception_index < 0) { + return false; + } + } + + if (cpu->exception_index >= EXCP_INTERRUPT) { + /* exit request from the cpu execution loop */ + *ret = cpu->exception_index; + if (*ret == EXCP_DEBUG) { + cpu_handle_debug_exception(cpu); + } + cpu->exception_index = -1; + return true; + } else { #if defined(CONFIG_USER_ONLY) - /* if user mode only, we simulate a fake exception - which will be handled outside the cpu execution - loop */ + /* if user mode only, we simulate a fake exception + which will be handled outside the cpu execution + loop */ #if defined(TARGET_I386) + CPUClass *cc = CPU_GET_CLASS(cpu); + cc->do_interrupt(cpu); +#endif + *ret = cpu->exception_index; + cpu->exception_index = -1; + return true; +#else + if (replay_exception()) { CPUClass *cc = CPU_GET_CLASS(cpu); + qemu_mutex_lock_iothread(); cc->do_interrupt(cpu); -#endif - *ret = cpu->exception_index; + qemu_mutex_unlock_iothread(); cpu->exception_index = -1; + } else if (!replay_has_interrupt()) { + /* give a chance to iothread in replay mode */ + *ret = EXCP_INTERRUPT; return true; -#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 */ - *ret = EXCP_INTERRUPT; - return true; - } -#endif } -#ifndef CONFIG_USER_ONLY - } else if (replay_has_exception() - && cpu->icount_decr.u16.low + cpu->icount_extra == 0) { - /* try to cause an exception pending in the log */ - cpu_exec_nocache(cpu, 1, tb_find(cpu, NULL, 0, curr_cflags()), true); - *ret = -1; - return true; #endif } @@ -522,6 +525,19 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, TranslationBlock **last_tb) { CPUClass *cc = CPU_GET_CLASS(cpu); + int32_t insns_left; + + /* Clear the interrupt flag now since we're processing + * cpu->interrupt_request and cpu->exit_request. + */ + insns_left = atomic_read(&cpu->icount_decr.u32); + atomic_set(&cpu->icount_decr.u16.high, 0); + if (unlikely(insns_left < 0)) { + /* Ensure the zeroing of icount_decr comes before the next read + * of cpu->exit_request or cpu->interrupt_request. + */ + smp_mb(); + } if (unlikely(atomic_read(&cpu->interrupt_request))) { int interrupt_request; @@ -620,17 +636,14 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb, *last_tb = NULL; insns_left = atomic_read(&cpu->icount_decr.u32); - atomic_set(&cpu->icount_decr.u16.high, 0); if (insns_left < 0) { /* 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 icount_decr - * comes before the next read of cpu->exit_request - * or cpu->interrupt_request. + * interrupt_request) which will be handled by + * cpu_handle_interrupt. cpu_handle_interrupt will also + * clear cpu->icount_decr.u16.high. */ - smp_mb(); return; } |