Re: [PATCH] x86: Wait for self IPI

[Paolo Bonzini <pbonzini@redhat.com>]

On 16/04/19 01:04, Nadav Amit wrote:
>> On Apr 15, 2019, at 4:03 PM, nadav.amit@gmail.com wrote:
>>
>> From: Nadav Amit <nadav.amit@gmail.com>
>>
>> There is no architectural requirement that self-IPI would be received on
>> the next instruction after it is generated. Make the test more robust by
>> not requiring it, and instead wait for some time or until it is
>> received.
>>
>> Signed-off-by: Nadav Amit <nadav.amit@gmail.com>
>> ---
>> x86/apic.c | 7 ++++++-
>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/x86/apic.c b/x86/apic.c
>> index 0849f87..de5990c 100644
>> --- a/x86/apic.c
>> +++ b/x86/apic.c
>> @@ -255,13 +255,18 @@ static void self_ipi_isr(isr_regs_t *regs)
>>
>> static void test_self_ipi(void)
>> {
>> +    u64 start = rdtsc();
>>     int vec = 0xf1;
>>
>>     handle_irq(vec, self_ipi_isr);
>>     irq_enable();
>>     apic_icr_write(APIC_DEST_SELF | APIC_DEST_PHYSICAL | APIC_DM_FIXED | vec,
>>                    0);
>> -    asm volatile ("nop");
>> +
>> +    do {
>> +        pause();
>> +    } while (rdtsc() - start < 1000000000 && ipi_count == 0);
>> +
>>     report("self ipi", ipi_count == 1);
>> }
>>
>> -- 
>> 2.17.1
> 
> This is of course a KVM-unit-tests patch.
> 

which I've queued, thanks.

Paolo