Commit 34396437 authored by Gavin Shan's avatar Gavin Shan Committed by Marc Zyngier
Browse files

KVM: selftests: memslot_perf_test: Probe memory slots for once 



prepare_vm() is called in every iteration and run. The allowed memory
slots (KVM_CAP_NR_MEMSLOTS) are probed for multiple times. It's not
free and unnecessary.

Move the probing logic for the allowed memory slots to parse_args()
for once, which is upper layer of prepare_vm().

No functional change intended.

Signed-off-by: default avatarGavin Shan <gshan@redhat.com>
Reviewed-by: default avatarMaciej S. Szmigiero <maciej.szmigiero@oracle.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221020071209.559062-4-gshan@redhat.com
parent 2aae5e67

tools/testing/selftests/kvm/memslot_perf_test.c

+19 −13
Original line number Diff line number Diff line
@@ -245,27 +245,17 @@ static bool prepare_vm(struct vm_data *data, int nslots, uint64_t *maxslots, 
		       void *guest_code, uint64_t mempages,

		       struct timespec *slot_runtime)

{

	uint32_t max_mem_slots;

	uint64_t rempages;

	uint64_t guest_addr;

	uint32_t slot;

	struct timespec tstart;

	struct sync_area *sync;



	max_mem_slots = kvm_check_cap(KVM_CAP_NR_MEMSLOTS);

	TEST_ASSERT(max_mem_slots > 1,

		    "KVM_CAP_NR_MEMSLOTS should be greater than 1");

	TEST_ASSERT(nslots > 1 || nslots == -1,

		    "Slot count cap should be greater than 1");

	if (nslots != -1)

		max_mem_slots = min(max_mem_slots, (uint32_t)nslots);

	pr_info_v("Allowed number of memory slots: %"PRIu32"\n", max_mem_slots);



	TEST_ASSERT(mempages > 1,

		    "Can't test without any memory");



	data->npages = mempages;

	data->nslots = max_mem_slots - 1;

	data->nslots = nslots;

	data->pages_per_slot = mempages / data->nslots;

	if (!data->pages_per_slot) {

		*maxslots = mempages + 1;
@@ -869,6 +859,7 @@ static void help(char *name, struct test_args *targs) 
static bool parse_args(int argc, char *argv[],

		       struct test_args *targs)

{

	uint32_t max_mem_slots;

	int opt;



	while ((opt = getopt(argc, argv, "hvds:f:e:l:r:")) != -1) {
@@ -885,8 +876,8 @@ static bool parse_args(int argc, char *argv[], 
			break;

		case 's':

			targs->nslots = atoi(optarg);

			if (targs->nslots <= 0 && targs->nslots != -1) {

				pr_info("Slot count cap has to be positive or -1 for no cap\n");

			if (targs->nslots <= 1 && targs->nslots != -1) {

				pr_info("Slot count cap must be larger than 1 or -1 for no cap\n");

				return false;

			}

			break;
@@ -932,6 +923,21 @@ static bool parse_args(int argc, char *argv[], 
		return false;

	}



	max_mem_slots = kvm_check_cap(KVM_CAP_NR_MEMSLOTS);

	if (max_mem_slots <= 1) {

		pr_info("KVM_CAP_NR_MEMSLOTS should be greater than 1\n");

		return false;

	}



	/* Memory slot 0 is reserved */

	if (targs->nslots == -1)

		targs->nslots = max_mem_slots - 1;

	else

		targs->nslots = min_t(int, targs->nslots, max_mem_slots) - 1;



	pr_info_v("Allowed Number of memory slots: %"PRIu32"\n",

		  targs->nslots + 1);



	return true;

}