[PATCH v4 05/10] KVM: selftests: Pass args to vCPU in global vCPU args struct

From: Ben Gardon
Date: Thu Jan 23 2020 - 13:04:57 EST


In preparation for supporting multiple vCPUs in the demand paging test,
pass arguments to the vCPU in a consolidated global struct instead of
syncing multiple globals.

Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx>
---
.../selftests/kvm/demand_paging_test.c | 38 +++++++++++++------
1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index 9d7514e96a639..9e2a5f7dfa140 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -42,7 +42,6 @@
*/
static uint64_t host_page_size;
static uint64_t guest_page_size;
-static uint64_t guest_num_pages;

static char *guest_data_prototype;

@@ -59,18 +58,30 @@ static uint64_t guest_test_phys_mem;
*/
static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM;

+struct vcpu_args {
+ uint64_t gva;
+ uint64_t pages;
+
+ /* Only used by the host userspace part of the vCPU thread */
+ int vcpu_id;
+ struct kvm_vm *vm;
+};
+
+static struct vcpu_args vcpu_args;
+
/*
* Continuously write to the first 8 bytes of each page in the demand paging
* memory region.
*/
static void guest_code(void)
{
+ uint64_t gva = vcpu_args.gva;
+ uint64_t pages = vcpu_args.pages;
int i;

- for (i = 0; i < guest_num_pages; i++) {
- uint64_t addr = guest_test_virt_mem;
+ for (i = 0; i < pages; i++) {
+ uint64_t addr = gva + (i * guest_page_size);

- addr += i * guest_page_size;
addr &= ~(host_page_size - 1);
*(uint64_t *)addr = 0x0123456789ABCDEF;
}
@@ -85,15 +96,16 @@ static uint64_t host_num_pages;
static void *vcpu_worker(void *data)
{
int ret;
- struct kvm_vm *vm = data;
+ struct kvm_vm *vm = vcpu_args.vm;
+ int vcpu_id = vcpu_args.vcpu_id;
struct kvm_run *run;

- run = vcpu_state(vm, VCPU_ID);
+ run = vcpu_state(vm, vcpu_id);

/* Let the guest access its memory */
- ret = _vcpu_run(vm, VCPU_ID);
+ ret = _vcpu_run(vm, vcpu_id);
TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
- if (get_ucall(vm, VCPU_ID, NULL) != UCALL_SYNC) {
+ if (get_ucall(vm, vcpu_id, NULL) != UCALL_SYNC) {
TEST_ASSERT(false,
"Invalid guest sync status: exit_reason=%s\n",
exit_reason_str(run->exit_reason));
@@ -285,6 +297,7 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
pthread_t uffd_handler_thread;
int pipefd[2];
struct kvm_vm *vm;
+ uint64_t guest_num_pages;
int r;

/*
@@ -370,10 +383,13 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd,
/* Export the shared variables to the guest */
sync_global_to_guest(vm, host_page_size);
sync_global_to_guest(vm, guest_page_size);
- sync_global_to_guest(vm, guest_test_virt_mem);
- sync_global_to_guest(vm, guest_num_pages);

- pthread_create(&vcpu_thread, NULL, vcpu_worker, vm);
+ vcpu_args.vm = vm;
+ vcpu_args.vcpu_id = VCPU_ID;
+ vcpu_args.gva = guest_test_virt_mem;
+ vcpu_args.pages = guest_num_pages;
+ sync_global_to_guest(vm, vcpu_args);
+ pthread_create(&vcpu_thread, NULL, vcpu_worker, &vcpu_args);

/* Wait for the vcpu thread to quit */
pthread_join(vcpu_thread, NULL);
--
2.25.0.341.g760bfbb309-goog