Re: [PATCH v2 04/10] s390x: smp: Test local interrupts after cpu reset

David Hildenbrand
2020-04-24T10:07:30Z

On 23.04.20 11:10, Janosch Frank wrote:
> Local interrupts (external and emergency call) should be cleared after
> any cpu reset.
>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>
> ---
> s390x/smp.c | 22 ++++++++++++++++++++++
> 1 file changed, 22 insertions(+)
>
> diff --git a/s390x/smp.c b/s390x/smp.c
> index 8a6cd1d..a8e3dd7 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);
> +}

I think last time I looked at this I got it all wrong. So, we actually
don't expect that an interrupt triggers here, correct?

The SIGP_CPU_RESET should have cleared both interrupts on this cpu. So
once we enable them, none should trigger.

Why do we have "expect_ext_int()" ?

> +
> 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");
> report_prefix_pop();
> }
>
>

--
Thanks,

David / dhildenb