Re: [PATCH] linux-user: Trace wait4()'s and waitpid()'s wstatus

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

On 10/5/24 10:57, Richard Henderson wrote:
> On 10/1/24 12:32, Ilya Leoshkevich wrote:
>> Borrow the code for formatting the most frequent WIFEXITED() and
>> WIFSIGNALED() special cases from from the strace's printstatus().
>>
>> Output examples:
>>
>>      474729 wait4(-1,0x7f00767ff0a0,0,(nil)) = 474733 (wstatus={WIFEXITED(s) && 
>> WEXITSTATUS(s) == 1})
>>      475833 wait4(-1,0x7f7de61ff0a0,0,(nil)) = 475837 (wstatus={WIFSIGNALED(s) && 
>> WTERMSIG(s) == SIGKILL})
>>      1168 waitpid(1171,0x7f44eea00340,0) = 1171 (wstatus={WIFSIGNALED(s) && WTERMSIG(s) 
>> == SIGKILL})
>>
>> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
>> ---
>>   linux-user/strace.c    | 61 ++++++++++++++++++++++++++++++++++++++++++
>>   linux-user/strace.list |  6 +++--
>>   2 files changed, 65 insertions(+), 2 deletions(-)
>>
>> diff --git a/linux-user/strace.c b/linux-user/strace.c
>> index b4d1098170e..d5d1f18304d 100644
>> --- a/linux-user/strace.c
>> +++ b/linux-user/strace.c
>> @@ -4168,6 +4168,67 @@ print_ioctl(CPUArchState *cpu_env, const struct syscallname *name,
>>   }
>>   #endif
>> +#if defined(TARGET_NR_wait4) || defined(TARGET_NR_waitpid)
>> +static void print_wstatus(int wstatus)
>> +{
>> +    if (WIFSIGNALED(wstatus)) {
>> +        qemu_log("{WIFSIGNALED(s) && WTERMSIG(s) == ");
>> +        print_signal(WTERMSIG(wstatus), 1);
>> +        if (WCOREDUMP(wstatus)) {
>> +            qemu_log(" && WCOREDUMP(s)");
>> +        }
>> +        qemu_log("}");
>> +    } else if (WIFEXITED(wstatus)) {
>> +        qemu_log("{WIFEXITED(s) && WEXITSTATUS(s) == %d}",
>> +                 WEXITSTATUS(wstatus));
>> +    } else {
>> +        print_number(wstatus, 1);
>> +    }
>> +}
>> +
>> +static void print_ret_wstatus(abi_long ret, abi_long wstatus_addr)
>> +{
>> +    if (!print_syscall_err(ret)) {
>> +        qemu_log(TARGET_ABI_FMT_ld " (wstatus=", ret);
>> +        if (wstatus_addr == 0) {
>> +            qemu_log("NULL");
> 
> I think you could merge the == 0 check into the outer IF, and avoid printing the returned 
> wstatus entirely.
> 
> Otherwise
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Adjusted and queued.

r~