[PATCH v2 2/2] KVM: selftests: Randomize pCPU in steal time test

[Sean Christopherson]

Pin the steal time test's tasks to a random pCPU in the system instead of
hardcoding the test to always run on pCPU0 as a cheap way of increasing
test coverage, and to do the "right thing" if the parent task of the test
doesn't have pCPU0 in its CPU affinity mask.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 tools/testing/selftests/kvm/steal_time.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
index a244bf9f701f..92e7ffcd68b7 100644
--- a/tools/testing/selftests/kvm/steal_time.c
+++ b/tools/testing/selftests/kvm/steal_time.c
@@ -514,14 +514,12 @@ int main(int ac, char **av)
 	long stolen_time;
 	long run_delay;
 	bool verbose;
-	int i;
+	int i, cpu;
 
 	verbose = ac > 1 && (!strncmp(av[1], "-v", 3) || !strncmp(av[1], "--verbose", 10));
 
 	/* Set CPU affinity so we can force preemption of the VCPU */
-	CPU_ZERO(&cpuset);
-	CPU_SET(0, &cpuset);
-	pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
+	cpu = pin_self_to_any_cpu();
 
 	/* Create a VM and an identity mapped memslot for the steal time structure */
 	vm = vm_create_with_vcpus(NR_VCPUS, guest_code, vcpus);
@@ -557,7 +555,7 @@ int main(int ac, char **av)
 		run_delay = get_run_delay();
 		pthread_create(&thread, NULL, do_steal_time, NULL);
 		pthread_getaffinity_np(thread, sizeof(cpuset), &cpuset);
-		TEST_ASSERT(CPU_COUNT(&cpuset) == 1 && CPU_ISSET(0, &cpuset),
+		TEST_ASSERT(CPU_COUNT(&cpuset) == 1 && CPU_ISSET(cpu, &cpuset),
 			    "Worker failed to inherit parent's CPU affinity");
 
 		do
-- 
2.55.0.rc2.803.g1fd1e6609c-goog