On Thu, Sep 15, 2022 at 12:04:48AM +0000, Vishal Annapurve wrote:
> Update xen specific hypercall invocation to execute cpu specific vmcall
> instructions.
>
> Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Signed-off-by: Vishal Annapurve <vannapurve@xxxxxxxxxx>
> ---
> .../selftests/kvm/x86_64/xen_shinfo_test.c | 64 +++++++------------
> .../selftests/kvm/x86_64/xen_vmcall_test.c | 14 ++--
> 2 files changed, 34 insertions(+), 44 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
> index 8a5cb800f50e..92ed07f1c772 100644
> --- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
> @@ -145,6 +145,23 @@ static void guest_wait_for_irq(void)
> guest_saw_irq = false;
> }
>
> +static unsigned long vmcall_helper(unsigned long reg_a, unsigned long reg_di,
> + unsigned long reg_si)
> +{
> + unsigned long ret;
> +
> + if (is_amd_cpu())
> + __asm__ __volatile__ ("vmmcall" :
> + "=a" (ret) :
> + "a" (reg_a), "D" (reg_di), "S" (reg_si));
> + else
> + __asm__ __volatile__ ("vmcall" :
> + "=a" (ret) :
> + "a" (reg_a), "D" (reg_di), "S" (reg_si));
> +
> + return ret;
> +}
> +
> static void guest_code(void)
> {
> struct vcpu_runstate_info *rs = (void *)RUNSTATE_VADDR;
> @@ -217,12 +234,7 @@ static void guest_code(void)
> * EVTCHNOP_send hypercall. */
> unsigned long rax;
> struct evtchn_send s = { .port = 127 };
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_event_channel_op),
> - "D" (EVTCHNOP_send),
> - "S" (&s));
> -
> + rax = vmcall_helper(__HYPERVISOR_event_channel_op, EVTCHNOP_send, (unsigned long)&s);
> GUEST_ASSERT(rax == 0);
>
> guest_wait_for_irq();
> @@ -232,12 +244,7 @@ static void guest_code(void)
> /* Deliver "outbound" event channel to an eventfd which
> * happens to be one of our own irqfds. */
> s.port = 197;
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_event_channel_op),
> - "D" (EVTCHNOP_send),
> - "S" (&s));
> -
> + rax = vmcall_helper(__HYPERVISOR_event_channel_op, EVTCHNOP_send, (unsigned long)&s);
> GUEST_ASSERT(rax == 0);
>
> guest_wait_for_irq();
> @@ -245,10 +252,7 @@ static void guest_code(void)
> GUEST_SYNC(13);
>
> /* Set a timer 100ms in the future. */
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_set_timer_op),
> - "D" (rs->state_entry_time + 100000000));
> + rax = vmcall_helper(__HYPERVISOR_set_timer_op, (rs->state_entry_time + 100000000), 0);
> GUEST_ASSERT(rax == 0);
>
> GUEST_SYNC(14);
> @@ -271,36 +275,21 @@ static void guest_code(void)
> .timeout = 0,
> };
>
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_sched_op),
> - "D" (SCHEDOP_poll),
> - "S" (&p));
> -
> + rax = vmcall_helper(__HYPERVISOR_sched_op, SCHEDOP_poll, (unsigned long)&p);
> GUEST_ASSERT(rax == 0);
>
> GUEST_SYNC(17);
>
> /* Poll for an unset port and wait for the timeout. */
> p.timeout = 100000000;
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_sched_op),
> - "D" (SCHEDOP_poll),
> - "S" (&p));
> -
> + rax = vmcall_helper(__HYPERVISOR_sched_op, SCHEDOP_poll, (unsigned long)&p);
> GUEST_ASSERT(rax == 0);
>
> GUEST_SYNC(18);
>
> /* A timer will wake the masked port we're waiting on, while we poll */
> p.timeout = 0;
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_sched_op),
> - "D" (SCHEDOP_poll),
> - "S" (&p));
> -
> + rax = vmcall_helper(__HYPERVISOR_sched_op, SCHEDOP_poll, (unsigned long)&p);
> GUEST_ASSERT(rax == 0);
>
> GUEST_SYNC(19);
> @@ -309,12 +298,7 @@ static void guest_code(void)
> * actual interrupt, while we're polling on a different port. */
> ports[0]++;
> p.timeout = 0;
> - __asm__ __volatile__ ("vmcall" :
> - "=a" (rax) :
> - "a" (__HYPERVISOR_sched_op),
> - "D" (SCHEDOP_poll),
> - "S" (&p));
> -
> + rax = vmcall_helper(__HYPERVISOR_sched_op, SCHEDOP_poll, (unsigned long)&p);
> GUEST_ASSERT(rax == 0);
>
> guest_wait_for_irq();
> diff --git a/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c b/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c
> index 88914d48c65e..e78f1b5d3af8 100644
> --- a/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/xen_vmcall_test.c
> @@ -37,10 +37,16 @@ static void guest_code(void)
> register unsigned long r9 __asm__("r9") = ARGVALUE(6);
>
> /* First a direct invocation of 'vmcall' */
> - __asm__ __volatile__("vmcall" :
> - "=a"(rax) :
> - "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
> - "r"(r10), "r"(r8), "r"(r9));
> + if (is_amd_cpu())
> + __asm__ __volatile__("vmmcall" :
> + "=a"(rax) :
> + "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
> + "r"(r10), "r"(r8), "r"(r9));
> + else
> + __asm__ __volatile__("vmcall" :
> + "=a"(rax) :
> + "a"(rax), "D"(rdi), "S"(rsi), "d"(rdx),
> + "r"(r10), "r"(r8), "r"(r9));
Can we create common helper functions or macros for doing hypercalls to
reduce the amount of duplicated inline assembly?
> GUEST_ASSERT(rax == RETVALUE);
>
> /* Fill in the Xen hypercall page */
> --
> 2.37.2.789.g6183377224-goog
>
