[PATCH v2 103/144] KVM: selftests: Convert set_boot_cpu_id away from global VCPU_IDs

Sean Christopherson
2022-06-03T00:56:26Z

Rework set_boot_cpu_id to pass around 'struct kvm_vcpu' objects instead
of relying on global VCPU_IDs. The test is still ugly, but that's
unavoidable since the point of the test is to verify that KVM correctly
assigns VCPU_ID==0 to be the BSP by default. This is literally one of
two KVM selftests that legitimately needs to care about the exact vCPU
IDs of the vCPUs it creates.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
.../selftests/kvm/x86_64/set_boot_cpu_id.c | 86 ++++++++-----------
1 file changed, 36 insertions(+), 50 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c b/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c
index e63709894030..b11f12888fad 100644
--- a/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c
+++ b/tools/testing/selftests/kvm/x86_64/set_boot_cpu_id.c
@@ -16,10 +16,6 @@
#include "processor.h"
#include "apic.h"

-#define N_VCPU 2
-#define VCPU_ID0 0
-#define VCPU_ID1 1
-
static void guest_bsp_vcpu(void *arg)
{
GUEST_SYNC(1);
@@ -38,31 +34,30 @@ static void guest_not_bsp_vcpu(void *arg)
GUEST_DONE();
}

-static void test_set_boot_busy(struct kvm_vm *vm)
+static void test_set_bsp_busy(struct kvm_vcpu *vcpu, const char *msg)
{
- int res;
+ int r = __vm_ioctl(vcpu->vm, KVM_SET_BOOT_CPU_ID,
+ (void *)(unsigned long)vcpu->id);

- res = __vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID0);
- TEST_ASSERT(res == -1 && errno == EBUSY,
- "KVM_SET_BOOT_CPU_ID set while running vm");
+ TEST_ASSERT(r == -1 && errno == EBUSY, "KVM_SET_BOOT_CPU_ID set %s", msg);
}

-static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid)
+static void run_vcpu(struct kvm_vcpu *vcpu)
{
struct ucall uc;
int stage;

for (stage = 0; stage < 2; stage++) {

- vcpu_run(vm, vcpuid);
+ vcpu_run(vcpu->vm, vcpu->id);

- switch (get_ucall(vm, vcpuid, &uc)) {
+ switch (get_ucall(vcpu->vm, vcpu->id, &uc)) {
case UCALL_SYNC:
TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") &&
uc.args[1] == stage + 1,
"Stage %d: Unexpected register values vmexit, got %lx",
stage + 1, (ulong)uc.args[1]);
- test_set_boot_busy(vm);
+ test_set_bsp_busy(vcpu, "while running vm");
break;
case UCALL_DONE:
TEST_ASSERT(stage == 1,
@@ -75,65 +70,56 @@ static void run_vcpu(struct kvm_vm *vm, uint32_t vcpuid)
uc.args[1], uc.args[2], uc.args[3]);
default:
TEST_ASSERT(false, "Unexpected exit: %s",
- exit_reason_str(vcpu_state(vm, vcpuid)->exit_reason));
+ exit_reason_str(vcpu->run->exit_reason));
}
}
}

-static struct kvm_vm *create_vm(void)
+static struct kvm_vm *create_vm(uint32_t nr_vcpus, uint32_t bsp_vcpu_id,
+ struct kvm_vcpu *vcpus[])
{
- uint64_t vcpu_pages = (DEFAULT_STACK_PGS) * 2;
- uint64_t extra_pg_pages = vcpu_pages / PTES_PER_MIN_PAGE * N_VCPU;
+ uint64_t vcpu_pages = (DEFAULT_STACK_PGS) * nr_vcpus;
+ uint64_t extra_pg_pages = vcpu_pages / PTES_PER_MIN_PAGE * nr_vcpus;
uint64_t pages = DEFAULT_GUEST_PHY_PAGES + vcpu_pages + extra_pg_pages;
+ struct kvm_vm *vm;
+ uint32_t i;

- return vm_create(pages);
-}
+ vm = vm_create(pages);

-static void add_x86_vcpu(struct kvm_vm *vm, uint32_t vcpuid, bool bsp_code)
-{
- if (bsp_code)
- vm_vcpu_add(vm, vcpuid, guest_bsp_vcpu);
- else
- vm_vcpu_add(vm, vcpuid, guest_not_bsp_vcpu);
+ vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *)(unsigned long)bsp_vcpu_id);
+
+ for (i = 0; i < nr_vcpus; i++)
+ vcpus[i] = vm_vcpu_add(vm, i, i == bsp_vcpu_id ? guest_bsp_vcpu :
+ guest_not_bsp_vcpu);
+ return vm;
}

-static void run_vm_bsp(uint32_t bsp_vcpu)
+static void run_vm_bsp(uint32_t bsp_vcpu_id)
{
+ struct kvm_vcpu *vcpus[2];
struct kvm_vm *vm;
- bool is_bsp_vcpu1 = bsp_vcpu == VCPU_ID1;
-
- vm = create_vm();
-
- if (is_bsp_vcpu1)
- vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID1);

- add_x86_vcpu(vm, VCPU_ID0, !is_bsp_vcpu1);
- add_x86_vcpu(vm, VCPU_ID1, is_bsp_vcpu1);
+ vm = create_vm(ARRAY_SIZE(vcpus), bsp_vcpu_id, vcpus);

- run_vcpu(vm, VCPU_ID0);
- run_vcpu(vm, VCPU_ID1);
+ run_vcpu(vcpus[0]);
+ run_vcpu(vcpus[1]);

kvm_vm_free(vm);
}

static void check_set_bsp_busy(void)
{
+ struct kvm_vcpu *vcpus[2];
struct kvm_vm *vm;
- int res;

- vm = create_vm();
+ vm = create_vm(ARRAY_SIZE(vcpus), 0, vcpus);

- add_x86_vcpu(vm, VCPU_ID0, true);
- add_x86_vcpu(vm, VCPU_ID1, false);
+ test_set_bsp_busy(vcpus[1], "after adding vcpu");

- res = __vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID1);
- TEST_ASSERT(res == -1 && errno == EBUSY, "KVM_SET_BOOT_CPU_ID set after adding vcpu");
+ run_vcpu(vcpus[0]);
+ run_vcpu(vcpus[1]);

- run_vcpu(vm, VCPU_ID0);
- run_vcpu(vm, VCPU_ID1);
-
- res = __vm_ioctl(vm, KVM_SET_BOOT_CPU_ID, (void *) VCPU_ID1);
- TEST_ASSERT(res == -1 && errno == EBUSY, "KVM_SET_BOOT_CPU_ID set to a terminated vcpu");
+ test_set_bsp_busy(vcpus[1], "to a terminated vcpu");

kvm_vm_free(vm);
}
@@ -145,9 +131,9 @@ int main(int argc, char *argv[])
return 0;
}

- run_vm_bsp(VCPU_ID0);
- run_vm_bsp(VCPU_ID1);
- run_vm_bsp(VCPU_ID0);
+ run_vm_bsp(0);
+ run_vm_bsp(1);
+ run_vm_bsp(0);

check_set_bsp_busy();
}
--
2.36.1.255.ge46751e96f-goog