Re: Questions about failing testcase nptl/test-mutex-printers

[Stefan Liebler <stli@linux.vnet.ibm.com>]

On 03/28/2018 03:15 PM, Carlos O'Donell wrote:
> On 03/28/2018 06:58 AM, Stefan Liebler wrote:
>> Does it make sense to disable lock-elision for the pretty-printer-tests?
> 
> Yes it does, and that is probably the correct answer in this case.
> 
> Many of the tests rely on looking at the internal details of the lock,
> particularly if you're going to pretty-print it, and elision does not allow
> that to happen because the lock and any modifications are elided.
> 
>> E.g. with the following patch:
>> diff --git a/scripts/test_printers_common.py b/scripts/test_printers_common.py
>> index 73ca525556..d74a8b4d4b 100644
>> --- a/scripts/test_printers_common.py
>> +++ b/scripts/test_printers_common.py
>> @@ -171,6 +171,9 @@ def init_test(test_bin, printer_files, printer_names):
>>       # Finally, load the test binary.
>>       test('file {0}'.format(test_bin))
>>
>> +    # Disable lock elision.
>> +    test('set environment GLIBC_TUNABLES glibc.elision.enable=0')
>> +
>>   def go_to_main():
>>       """Executes a gdb 'start' command, which takes us to main."""
> 
> Someone would have to confirm on at least one other arch to make sure this works
> as expected.
> 

PING.
Is there anybody with an intel / power lock-elision machine who can test 
this?