Re: [PATCH v2 10/11] selftests: KVM: Refactor psci_test to make it amenable to new tests

From: Oliver Upton <oupton@google.com>
To: Andrew Jones <drjones@redhat.com>
Cc: kvmarm@lists.cs.columbia.edu, Marc Zyngier <maz@kernel.org>,
	James Morse <james.morse@arm.com>,
	Alexandru Elisei <Alexandru.Elisei@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Peter Shier <pshier@google.com>,
	Ricardo Koller <ricarkol@google.com>,
	Reiji Watanabe <reijiw@google.com>,
	Raghavendra Rao Anata <rananta@google.com>,
	kvm@vger.kernel.org
Subject: Re: [PATCH v2 10/11] selftests: KVM: Refactor psci_test to make it amenable to new tests
Date: Tue, 5 Oct 2021 07:54:01 -0700	[thread overview]
Message-ID: <CAOQ_QsjQ28b8OXLR1o8QD=M8dsBKtPLyB-QRyd=D1UVMGy6o0w@mail.gmail.com> (raw)
In-Reply-To: <20211005134539.s7kzhqlg2pykfcam@gator.home>

Hi Drew,

On Tue, Oct 5, 2021 at 6:45 AM Andrew Jones <drjones@redhat.com> wrote:
>
> On Thu, Sep 23, 2021 at 07:16:09PM +0000, Oliver Upton wrote:
> > Split up the current test into several helpers that will be useful to
> > subsequent test cases added to the PSCI test suite.
> >
> > Signed-off-by: Oliver Upton <oupton@google.com>
> > ---
> >  .../testing/selftests/kvm/aarch64/psci_test.c | 68 ++++++++++++-------
> >  1 file changed, 45 insertions(+), 23 deletions(-)
> >
> > diff --git a/tools/testing/selftests/kvm/aarch64/psci_test.c b/tools/testing/selftests/kvm/aarch64/psci_test.c
> > index 8d043e12b137..90312be335da 100644
> > --- a/tools/testing/selftests/kvm/aarch64/psci_test.c
> > +++ b/tools/testing/selftests/kvm/aarch64/psci_test.c
> > @@ -45,7 +45,7 @@ static uint64_t psci_affinity_info(uint64_t target_affinity,
> >       return res.a0;
> >  }
> >
> > -static void guest_main(uint64_t target_cpu)
> > +static void guest_test_cpu_on(uint64_t target_cpu)
> >  {
> >       GUEST_ASSERT(!psci_cpu_on(target_cpu, CPU_ON_ENTRY_ADDR, CPU_ON_CONTEXT_ID));
> >       uint64_t target_state;
> > @@ -69,12 +69,10 @@ static void vcpu_power_off(struct kvm_vm *vm, uint32_t vcpuid)
> >       vcpu_set_mp_state(vm, vcpuid, &mp_state);
> >  }
> >
> > -int main(void)
> > +static struct kvm_vm *setup_vm(void *guest_code)
> >  {
> > -     uint64_t target_mpidr, obs_pc, obs_x0;
> >       struct kvm_vcpu_init init;
> >       struct kvm_vm *vm;
> > -     struct ucall uc;
> >
> >       vm = vm_create(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES, O_RDWR);
> >       kvm_vm_elf_load(vm, program_invocation_name);
> > @@ -83,31 +81,28 @@ int main(void)
> >       vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init);
> >       init.features[0] |= (1 << KVM_ARM_VCPU_PSCI_0_2);
> >
> > -     aarch64_vcpu_add_default(vm, VCPU_ID_SOURCE, &init, guest_main);
> > -     aarch64_vcpu_add_default(vm, VCPU_ID_TARGET, &init, guest_main);
> > +     aarch64_vcpu_add_default(vm, VCPU_ID_SOURCE, &init, guest_code);
> > +     aarch64_vcpu_add_default(vm, VCPU_ID_TARGET, &init, guest_code);
> >
> > -     /*
> > -      * make sure the target is already off when executing the test.
> > -      */
> > -     vcpu_power_off(vm, VCPU_ID_TARGET);
> > +     return vm;
> > +}
> >
> > -     get_reg(vm, VCPU_ID_TARGET, ARM64_SYS_REG(MPIDR_EL1), &target_mpidr);
> > -     vcpu_args_set(vm, VCPU_ID_SOURCE, 1, target_mpidr & MPIDR_HWID_BITMASK);
> > -     vcpu_run(vm, VCPU_ID_SOURCE);
> > +static void enter_guest(struct kvm_vm *vm, uint32_t vcpuid)
> > +{
> > +     struct ucall uc;
> >
> > -     switch (get_ucall(vm, VCPU_ID_SOURCE, &uc)) {
> > -     case UCALL_DONE:
> > -             break;
> > -     case UCALL_ABORT:
> > +     vcpu_run(vm, vcpuid);
> > +     if (get_ucall(vm, vcpuid, &uc) == UCALL_ABORT)
> >               TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0], __FILE__,
> >                         uc.args[1]);
> > -             break;
> > -     default:
> > -             TEST_FAIL("Unhandled ucall: %lu", uc.cmd);
> > -     }
> > +}
> >
> > -     get_reg(vm, VCPU_ID_TARGET, ARM64_CORE_REG(regs.pc), &obs_pc);
> > -     get_reg(vm, VCPU_ID_TARGET, ARM64_CORE_REG(regs.regs[0]), &obs_x0);
> > +static void assert_vcpu_reset(struct kvm_vm *vm, uint32_t vcpuid)
> > +{
> > +     uint64_t obs_pc, obs_x0;
> > +
> > +     get_reg(vm, vcpuid, ARM64_CORE_REG(regs.pc), &obs_pc);
> > +     get_reg(vm, vcpuid, ARM64_CORE_REG(regs.regs[0]), &obs_x0);
> >
> >       TEST_ASSERT(obs_pc == CPU_ON_ENTRY_ADDR,
> >                   "unexpected target cpu pc: %lx (expected: %lx)",
> > @@ -115,7 +110,34 @@ int main(void)
> >       TEST_ASSERT(obs_x0 == CPU_ON_CONTEXT_ID,
> >                   "unexpected target context id: %lx (expected: %lx)",
> >                   obs_x0, CPU_ON_CONTEXT_ID);
> > +}
> >
> > +static void host_test_cpu_on(void)
> > +{
> > +     uint64_t target_mpidr;
> > +     struct kvm_vm *vm;
> > +     struct ucall uc;
> > +
> > +     vm = setup_vm(guest_test_cpu_on);
> > +
> > +     /*
> > +      * make sure the target is already off when executing the test.
> > +      */
> > +     vcpu_power_off(vm, VCPU_ID_TARGET);
> > +
> > +     get_reg(vm, VCPU_ID_TARGET, ARM64_SYS_REG(MPIDR_EL1), &target_mpidr);
> > +     vcpu_args_set(vm, VCPU_ID_SOURCE, 1, target_mpidr & MPIDR_HWID_BITMASK);
> > +     enter_guest(vm, VCPU_ID_SOURCE);
> > +
> > +     if (get_ucall(vm, VCPU_ID_SOURCE, &uc) != UCALL_DONE)
> > +             TEST_FAIL("Unhandled ucall: %lu", uc.cmd);
> > +
> > +     assert_vcpu_reset(vm, VCPU_ID_TARGET);
> >       kvm_vm_free(vm);
> > +}
> > +
> > +int main(void)
> > +{
> > +     host_test_cpu_on();
> >       return 0;
> >  }
> > --
> > 2.33.0.685.g46640cef36-goog
> >
>
> Hard to read diff, but I think the refactoring comes out right.

Yeah, this one's nasty, sorry about that. Thanks for parsing it out, heh.

> Please do this refactoring before adding the new test in the next revision, though.
>

This is 10/11 in the series, and the test is 11/11. I'm not seeing any
context belonging to the last patch, but perhaps I'm missing something
obvious.

> Reviewed-by: Andrew Jones <drjones@redhat.com>

Thanks!

--
Best,
Oliver