[PATCH 08/15] KVM: selftests: Use perf util's per-vCPU GPA/pages in demand paging test

From: Sean Christopherson
Date: Wed Feb 10 2021 - 18:10:43 EST


Grab the per-vCPU GPA and number of pages from perf_util in the demand
paging test instead of duplicating perf_util's calculations.

Note, this may or may not result in a functional change. It's not clear
that the test's calculations are guaranteed to yield the same value as
perf_util, e.g. if guest_percpu_mem_size != vcpu_args->pages.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
.../selftests/kvm/demand_paging_test.c | 20 +++++--------------
1 file changed, 5 insertions(+), 15 deletions(-)

diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index 5f7a229c3af1..0cbf111e6c21 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -294,24 +294,13 @@ static void run_test(enum vm_guest_mode mode, void *arg)
TEST_ASSERT(pipefds, "Unable to allocate memory for pipefd");

for (vcpu_id = 0; vcpu_id < nr_vcpus; vcpu_id++) {
- vm_paddr_t vcpu_gpa;
+ struct perf_test_vcpu_args *vcpu_args;
void *vcpu_hva;
- uint64_t vcpu_mem_size;

-
- if (p->partition_vcpu_memory_access) {
- vcpu_gpa = guest_test_phys_mem +
- (vcpu_id * guest_percpu_mem_size);
- vcpu_mem_size = guest_percpu_mem_size;
- } else {
- vcpu_gpa = guest_test_phys_mem;
- vcpu_mem_size = guest_percpu_mem_size * nr_vcpus;
- }
- PER_VCPU_DEBUG("Added VCPU %d with test mem gpa [%lx, %lx)\n",
- vcpu_id, vcpu_gpa, vcpu_gpa + vcpu_mem_size);
+ vcpu_args = &perf_test_args.vcpu_args[vcpu_id];

/* Cache the HVA pointer of the region */
- vcpu_hva = addr_gpa2hva(vm, vcpu_gpa);
+ vcpu_hva = addr_gpa2hva(vm, vcpu_args->gpa);

/*
* Set up user fault fd to handle demand paging
@@ -325,7 +314,8 @@ static void run_test(enum vm_guest_mode mode, void *arg)
&uffd_handler_threads[vcpu_id],
pipefds[vcpu_id * 2],
p->uffd_delay, &uffd_args[vcpu_id],
- vcpu_hva, vcpu_mem_size);
+ vcpu_hva,
+ vcpu_args->pages * perf_test_args.guest_page_size);
if (r < 0)
exit(-r);
}
--
2.30.0.478.g8a0d178c01-goog