Re: [PATCH] linux-user/strace: show TID instead of PID

[Richard Henderson <richard.henderson@linaro.org>]

On 11/11/24 06:59, Richard Henderson wrote:
> On 10/23/24 16:47, J. Neuschäfer wrote:
>> This aligns with strace, and is very useful when tracing multi-threaded
>> programs. The result is the same in single-threaded programs.
> 
> See also "-D log.%d -d tid -strace" which will split the output into per-tid files.
> 
>>
>> gettid() requires the _GNU_SOURCE feature test macro, so it might be
>> unavailable in rare cases. I don't expect it to be a problem though,
>> because it's implemented by both glibc and musl.
>>
>> Signed-off-by: J. Neuschäfer <j.neuschaefer@gmx.net>
>> ---
>>   linux-user/strace.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/linux-user/strace.c b/linux-user/strace.c
>> index c3eb3a2706a93fdcaf693b3413b13921a3c97e8e..93e8c73de8a4a307e6e0df5555bee4c769e41e64 
>> 100644
>> --- a/linux-user/strace.c
>> +++ b/linux-user/strace.c
>> @@ -4337,7 +4337,7 @@ print_syscall(CPUArchState *cpu_env, int num,
>>       if (!f) {
>>           return;
>>       }
>> -    fprintf(f, "%d ", getpid());
>> +    fprintf(f, "%d ", gettid());
> 
> Probably better as qemu_get_thread_id(), but otherwise

Or, without the syscall,

   get_task_state(env_cpu(env))->ts_tid


r~