On 19/12/2016 17:04, Radim Krčmář wrote:
> Broadcast to address 0xff is not exercised by seabios+linux so we better
> test it.
>
> Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx>
> ---
> The bounded wait loop is bad ... time to introduce TSC magic?
Yeah, the VMX tests already use the TSC (though in the other direction:
they check that _at least_ some time passed). Roughly speaking, 1
billion TSC units should be plenty, even on a loaded hosts.
Paolo
> x86/apic.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 46 insertions(+)
>
> diff --git a/x86/apic.c b/x86/apic.c
> index 39c7fd19913d..b25ba45e4b8f 100644
> --- a/x86/apic.c
> +++ b/x86/apic.c
> @@ -5,6 +5,7 @@
> #include "desc.h"
> #include "isr.h"
> #include "msr.h"
> +#include "atomic.h"
>
> static void test_lapic_existence(void)
> {
> @@ -16,6 +17,7 @@ static void test_lapic_existence(void)
> }
>
> #define TSC_DEADLINE_TIMER_VECTOR 0xef
> +#define BROADCAST_VECTOR 0xcf
>
> static int tdt_count;
>
> @@ -411,6 +413,49 @@ static void test_apic_timer_one_shot(void)
> (tsc2 - tsc1 >= interval));
> }
>
> +static atomic_t broadcast_counter;
> +
> +static void broadcast_handler(isr_regs_t *regs)
> +{
> + atomic_inc(&broadcast_counter);
> + eoi();
> +}
> +
> +static bool broadcast_received(unsigned ncpus)
> +{
> + unsigned counter;
> +
> + for (int i = 123456789; i; i--) {
> + counter = atomic_read(&broadcast_counter);
> + if (counter >= ncpus)
> + break;
> + pause();
> + }
> +
> + atomic_set(&broadcast_counter, 0);
> +
> + return counter == ncpus;
> +}
> +
> +static void test_physical_broadcast(void)
> +{
> + unsigned ncpus = cpu_count();
> + unsigned long cr3 = read_cr3();
> + u32 broadcast_address = enable_x2apic() ? 0xffffffff : 0xff;
> +
> + handle_irq(BROADCAST_VECTOR, broadcast_handler);
> + for (int c = 1; c < ncpus; c++)
> + on_cpu(c, update_cr3, (void *)cr3);
> +
> + apic_icr_write(APIC_DEST_PHYSICAL | APIC_DM_FIXED | APIC_INT_ASSERT |
> + BROADCAST_VECTOR, broadcast_address);
> + report("APIC physical broadcast address", broadcast_received(ncpus));
> +
> + apic_icr_write(APIC_DEST_PHYSICAL | APIC_DM_FIXED | APIC_INT_ASSERT |
> + BROADCAST_VECTOR | APIC_DEST_ALLINC, 0);
> + report("APIC physical broadcast shorthand", broadcast_received(ncpus));
> +}
> +
> int main()
> {
> setup_vm();
> @@ -425,6 +470,7 @@ int main()
> test_apicbase();
>
> test_self_ipi();
> + test_physical_broadcast();
>
> test_sti_nmi();
> test_multiple_nmi();
>
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