cachepc

kvm-eviction.c (4002B)

#include "test/kvm-eviction.h"
#include "test/kvm.h"
#include "test/util.h"
#include "cachepc/uapi.h"

#include <sys/ioctl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <fcntl.h>
#include <err.h>
#include <string.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>

#define SAMPLE_COUNT 64

void
collect(struct kvm *kvm, uint8_t *counts)
{
	int ret;

	ret = ioctl(kvm->vcpufd, KVM_RUN, NULL);
	if (ret == -1) err(1, "KVM_RUN");

	if (kvm->run->exit_reason == KVM_EXIT_MMIO) {
		errx(1, "KVM died from OOB access! rip:%lu addr:%lu",
			vm_get_rip(), kvm->run->mmio.phys_addr);
	} else if (kvm->run->exit_reason != KVM_EXIT_HLT) {
		errx(1, "KVM died! rip:%lu code:%i",
			vm_get_rip(), kvm->run->exit_reason);
	}

	ret = ioctl(kvm_dev, KVM_CPC_READ_COUNTS, counts);
	if (ret == -1) err(1, "KVM_CPC_READ_COUNTS");
}

int
main(int argc, const char **argv)
{
	struct kvm vms[2];
	struct guest guests[2];
	uint8_t counts[2][SAMPLE_COUNT][L1_SETS];
	uint8_t baseline[L1_SETS];
	struct cpc_track_cfg cfg;
	int i, k, ret, exitcode;

	setvbuf(stdout, NULL, _IONBF, 0);

	parse_vmtype(argc, argv);

	pin_process(0, TARGET_CORE, true);

	kvm_setup_init();

	guest_init(&guests[WITH], "test/kvm-eviction-with_guest");
	vm_init(&vms[WITH], &guests[WITH]);
	guest_deinit(&guests[WITH]);

	guest_init(&guests[WITHOUT], "test/kvm-eviction-without_guest");
	vm_init(&vms[WITHOUT], &guests[WITHOUT]);
	guest_deinit(&guests[WITHOUT]);

	/* reset kernel module state */
	ret = ioctl(kvm_dev, KVM_CPC_RESET);
	if (ret == -1) err(1, "KVM_CPC_RESET");

	memset(&cfg, 0, sizeof(cfg));
	cfg.mode = CPC_TRACK_EXIT_EVICTIONS;
	ret = ioctl(kvm_dev, KVM_CPC_TRACK_MODE, &cfg);
	if (ret == -1) err(1, "KVM_CPC_TRACK_MODE");

	/* resolve page faults in advance (code only covers 1 page)..
	 * we want the read counts to apply between KVM_RUN and KVM_EXIT_HLT,
	 * any exits through PFs inbetween will influence our measurement */
	collect(&vms[WITH], counts[WITH][0]);
	collect(&vms[WITHOUT], counts[WITHOUT][0]);

	/* collect samples */
	for (i = 0; i < SAMPLE_COUNT; i++) {
		collect(&vms[WITH], counts[WITH][i]);
		collect(&vms[WITHOUT], counts[WITHOUT][i]);
	}

	/* calculate measurement baseline */
	memset(baseline, 0xff, L1_SETS);
	for (i = 0; i < SAMPLE_COUNT; i++) {
		for (k = 0; k < L1_SETS; k++) {
			if (counts[WITH][i][k] < baseline[k])
				baseline[k] = counts[WITH][i][k];
			if (counts[WITHOUT][i][k] < baseline[k])
				baseline[k] = counts[WITHOUT][i][k];
		}
	}

	printf("=== Baseline ===\n\n", i);
	print_counts(baseline);
	printf("\n");
	print_counts_raw(baseline);
	printf("\n");

	/* apply baseline and output samples */
	for (i = 0; i < SAMPLE_COUNT; i++) {
		for (k = 0; k < L1_SETS; k++) {
			counts[WITH][i][k] -= baseline[k];
			counts[WITHOUT][i][k] -= baseline[k];
		}

		printf("=== Sample %2i ===\n", i);

		printf("\nWith eviction:\n\n");
		print_counts(counts[WITH][i]);
		printf("\n");
		print_counts_raw(counts[WITH][i]);

		printf("\nWithout eviction:\n\n");
		print_counts(counts[WITHOUT][i]);
		printf("\n");
		print_counts_raw(counts[WITHOUT][i]);
		printf("\n");
	}

	/* check for measurment errors */
	exitcode = 0;
	for (i = 0; i < SAMPLE_COUNT; i++) {
		for (k = 0; k < L1_SETS; k++) {
			if (counts[WITH][i][k] + baseline[k] > L1_ASSOC) {
				warnx("sample %i: With count OOB for set %i (=%i)",
					i, k, counts[WITH][i][k] + baseline[k]);
				exitcode = 1;
			}

			if (counts[WITHOUT][i][k] + baseline[k] > L1_ASSOC) {
				warnx("sample %i: Without count OOB for set %i (=%i)",
					i, k, counts[WITHOUT][i][k] + baseline[k]);
				exitcode = 1;
			}
		}

		if (!counts[WITH][i][TARGET_SET]) {
			warnx("sample %i: Missing eviction in target set %i (=%i,%i)",
				i, TARGET_SET, counts[WITH][i][TARGET_SET],
				counts[WITH][i][TARGET_SET] + baseline[TARGET_SET]);
			exitcode = 1;
		}
	}

	vm_deinit(&vms[WITH]);
	vm_deinit(&vms[WITHOUT]);

	ret = ioctl(kvm_dev, KVM_CPC_DEINIT);
	if (ret == -1) err(1, "KVM_CPC_DEINIT");

	kvm_setup_deinit();

	return exitcode;
}