On 01.04.20 09:19, Janosch Frank wrote:
> On 3/31/20 7:27 PM, David Hildenbrand wrote:
>> On 31.03.20 11:28, Janosch Frank wrote:
>>> On 3/31/20 11:07 AM, David Hildenbrand wrote:
>>>> On 24.03.20 09:12, Janosch Frank wrote:
>>>>> Local interrupts (external and emergency call) should be cleared after
>>>>> any cpu reset.
>>>>>
>>>>> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
>>>>> ---
>>>>> s390x/smp.c | 22 ++++++++++++++++++++++
>>>>> 1 file changed, 22 insertions(+)
>>>>>
>>>>> diff --git a/s390x/smp.c b/s390x/smp.c
>>>>> index 8a6cd1d8b17d76c6..a8e3dd7aac0c788c 100644
>>>>> --- a/s390x/smp.c
>>>>> +++ b/s390x/smp.c
>>>>> @@ -243,6 +243,20 @@ static void test_reset_initial(void)
>>>>> report_prefix_pop();
>>>>> }
>>>>>
>>>>> +static void test_local_ints(void)
>>>>> +{
>>>>> + unsigned long mask;
>>>>> +
>>>>> + expect_ext_int();
>>>>> + /* Open masks for ecall and emcall */
>>>>> + ctl_set_bit(0, 13);
>>>>> + ctl_set_bit(0, 14);
>>>>> + mask = extract_psw_mask();
>>>>> + mask |= PSW_MASK_EXT;
>>>>> + load_psw_mask(mask);
>>>>> + set_flag(1);
>>>>> +}
>>>>> +
>>>>> static void test_reset(void)
>>>>> {
>>>>> struct psw psw;
>>>>> @@ -251,10 +265,18 @@ static void test_reset(void)
>>>>> psw.addr = (unsigned long)test_func;
>>>>>
>>>>> report_prefix_push("cpu reset");
>>>>> + sigp(1, SIGP_EMERGENCY_SIGNAL, 0, NULL);
>>>>> + sigp(1, SIGP_EXTERNAL_CALL, 0, NULL);
>>>>> smp_cpu_start(1, psw);
>>>>>
>>>>> sigp_retry(1, SIGP_CPU_RESET, 0, NULL);
>>>>> report(smp_cpu_stopped(1), "cpu stopped");
>>>>> +
>>>>> + set_flag(0);
>>>>> + psw.addr = (unsigned long)test_local_ints;
>>>>> + smp_cpu_start(1, psw);
>>>>> + wait_for_flag();
>>>>> + report(true, "local interrupts cleared");
>>>>
>>>>
>>>> How can you be sure they were actually cleared/delivered?
>>>>
>>> Because cpu 1 would get a ext int it didn't expect and would do a
>>> report_abort() as pecified in lib/s390x/interrupt.c
>>
>> But what if it *didn't* get the interrupts delivered.
>
> Well, the target is still looping until the reset initial test is
> executed and from personal experience I can say that this test bites
> rather fast.
>
> We could execute an instruction with a mandatory exit which will prompt
> KVM to inject any remaining IRQs before setting the flag to 1.
>
> Unfortunately we do not have a polling instruction for non-IO interrupts
> at the moment to verify this test.
I'd expect you should do something like this in your test instead
static void test_local_ints(void)
{
unsigned long mask;
/* Enable external interrupts */
mask = extract_psw_mask();
mask |= PSW_MASK_EXT;
load_psw_mask(mask);
expect_ext_int();
/* Open masks for external call */
ctl_set_bit(0, 13);
if (lc->ext_int_code != $TODO1)
return;
expect_ext_int();
/* Open masks for emergency call */
ctl_set_bit(0, 14);
if (lc->ext_int_code != $TODO2)
return;
set_flag(1);
}
--
Thanks,
David / dhildenb
