Re: [Qemu-devel] [PATCH] monitor: Check whether TCG is enabled before running the "info jit" code

[Peter Maydell]

On 26 April 2017 at 09:18, Dr. David Alan Gilbert <address@hidden> wrote:
> * Thomas Huth (address@hidden) wrote:
>> The "info jit" command currently aborts on Mac OS X with the message
>> "qemu_mutex_lock: Invalid argument" when running with "-M accel=qtest".
>> We should only call into the TCG code here if TCG has really been
>> enabled and initialized.
>>
>> Signed-off-by: Thomas Huth <address@hidden>
>> ---
>>  monitor.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/monitor.c b/monitor.c
>> index be282ec..3e0979d 100644
>> --- a/monitor.c
>> +++ b/monitor.c
>> @@ -1086,6 +1086,11 @@ static void hmp_info_registers(Monitor *mon, const 
>> QDict *qdict)
>>
>>  static void hmp_info_jit(Monitor *mon, const QDict *qdict)
>>  {
>> +    if (!tcg_enabled()) {
>> +        error_report("JIT information is only available with accel=tcg");
>> +        return;
>> +    }
>> +
>>      dump_exec_info((FILE *)mon, monitor_fprintf);
>>      dump_drift_info((FILE *)mon, monitor_fprintf);
>>  }
>
> so tcg_enabled checks tcg_ctx.code_gen_buffer != NULL
> code_gen_buffer is set by code_gen_alloc
> code_gen_alloc does a qemu_mutex_init of tb_lock
> and the previous problem was an uninitialised tb_lock.
>
> So:
> Reviewed-by: Dr. David Alan Gilbert <address@hidden>
>
>
> Peter: Does this fix the hmp test for you?

Yes, it does.

Tested-by: Peter Maydell <address@hidden>

-- PMM