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

[David Hildenbrand <david@redhat.com>]

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