Re: [kvm-unit-tests PATCH v2 3/9] s390x: irq: make IRQ handler weak

Thomas Huth
2019-12-02T10:41:42Z

On 29/11/2019 13.01, David Hildenbrand wrote:
> On 28.11.19 13:46, Pierre Morel wrote:
>> Having a weak function allows the tests programm to declare its own
>> IRQ handler.
>> This is helpfull for I/O tests to have the I/O IRQ handler having
>> its special work to do.
>>
>> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
>> Reviewed-by: Thomas Huth <thuth@redhat.com>
>> ---
>> lib/s390x/interrupt.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/lib/s390x/interrupt.c b/lib/s390x/interrupt.c
>> index 3e07867..d70fde3 100644
>> --- a/lib/s390x/interrupt.c
>> +++ b/lib/s390x/interrupt.c
>> @@ -140,7 +140,7 @@ void handle_mcck_int(void)
>> lc->mcck_old_psw.addr);
>> }
>>
>> -void handle_io_int(void)
>> +__attribute__((weak)) void handle_io_int(void)
>> {
>> report_abort("Unexpected io interrupt: at %#lx",
>> lc->io_old_psw.addr);
>>
>
> The clear alternative would be a way to register a callback function.
> That way you can modify the callback during the tests. As long as not
> registered, wrong I/Os can be caught easily here. @Thomas?

I don't mind too much, but I think I'd also slightly prefer a registered
callback function here instead.

Thomas