Commit 1eafbd27 authored by Ben Gardon's avatar Ben Gardon Committed by Paolo Bonzini
Browse files

KVM: selftests: Simplify demand_paging_test with timespec_diff_now 



Add a helper function to get the current time and return the time since
a given start time. Use that function to simplify the timekeeping in the
demand paging test.

This series was tested by running the following invocations on an Intel
Skylake machine:
dirty_log_perf_test -b 20m -i 100 -v 64
dirty_log_perf_test -b 20g -i 5 -v 4
dirty_log_perf_test -b 4g -i 5 -v 32
demand_paging_test -b 20m -v 64
demand_paging_test -b 20g -v 4
demand_paging_test -b 4g -v 32
All behaved as expected.

Signed-off-by: default avatarBen Gardon <bgardon@google.com>
Message-Id: <20201027233733.1484855-4-bgardon@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 2fe5149b

tools/testing/selftests/kvm/demand_paging_test.c

+13 −13
Original line number Diff line number Diff line
@@ -50,7 +50,8 @@ static void *vcpu_worker(void *data) 
	int vcpu_id = vcpu_args->vcpu_id;

	struct kvm_vm *vm = perf_test_args.vm;

	struct kvm_run *run;

	struct timespec start, end, ts_diff;

	struct timespec start;

	struct timespec ts_diff;



	vcpu_args_set(vm, vcpu_id, 1, vcpu_id);

	run = vcpu_state(vm, vcpu_id);
@@ -66,8 +67,7 @@ static void *vcpu_worker(void *data) 
			    exit_reason_str(run->exit_reason));

	}



	clock_gettime(CLOCK_MONOTONIC, &end);

	ts_diff = timespec_sub(end, start);

	ts_diff = timespec_diff_now(start);

	PER_VCPU_DEBUG("vCPU %d execution time: %ld.%.9lds\n", vcpu_id,

		       ts_diff.tv_sec, ts_diff.tv_nsec);
@@ -78,7 +78,7 @@ static int handle_uffd_page_request(int uffd, uint64_t addr) 
{

	pid_t tid;

	struct timespec start;

	struct timespec end;

	struct timespec ts_diff;

	struct uffdio_copy copy;

	int r;
@@ -98,10 +98,10 @@ static int handle_uffd_page_request(int uffd, uint64_t addr) 
		return r;

	}



	clock_gettime(CLOCK_MONOTONIC, &end);

	ts_diff = timespec_diff_now(start);



	PER_PAGE_DEBUG("UFFDIO_COPY %d \t%ld ns\n", tid,

		       timespec_to_ns(timespec_sub(end, start)));

		       timespec_to_ns(ts_diff));

	PER_PAGE_DEBUG("Paged in %ld bytes at 0x%lx from thread %d\n",

		       perf_test_args.host_page_size, addr, tid);
@@ -123,7 +123,8 @@ static void *uffd_handler_thread_fn(void *arg) 
	int pipefd = uffd_args->pipefd;

	useconds_t delay = uffd_args->delay;

	int64_t pages = 0;

	struct timespec start, end, ts_diff;

	struct timespec start;

	struct timespec ts_diff;



	clock_gettime(CLOCK_MONOTONIC, &start);

	while (!quit_uffd_thread) {
@@ -192,8 +193,7 @@ static void *uffd_handler_thread_fn(void *arg) 
		pages++;

	}



	clock_gettime(CLOCK_MONOTONIC, &end);

	ts_diff = timespec_sub(end, start);

	ts_diff = timespec_diff_now(start);

	PER_VCPU_DEBUG("userfaulted %ld pages over %ld.%.9lds. (%f/sec)\n",

		       pages, ts_diff.tv_sec, ts_diff.tv_nsec,

		       pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / 100000000.0));
@@ -257,7 +257,8 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd, 
	pthread_t *vcpu_threads;

	pthread_t *uffd_handler_threads = NULL;

	struct uffd_handler_args *uffd_args = NULL;

	struct timespec start, end, ts_diff;

	struct timespec start;

	struct timespec ts_diff;

	int *pipefds = NULL;

	struct kvm_vm *vm;

	int vcpu_id;
@@ -335,9 +336,9 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd, 
		PER_VCPU_DEBUG("Joined thread for vCPU %d\n", vcpu_id);

	}



	pr_info("All vCPU threads joined\n");

	ts_diff = timespec_diff_now(start);



	clock_gettime(CLOCK_MONOTONIC, &end);

	pr_info("All vCPU threads joined\n");



	if (use_uffd) {

		char c;
@@ -351,7 +352,6 @@ static void run_test(enum vm_guest_mode mode, bool use_uffd, 
		}

	}



	ts_diff = timespec_sub(end, start);

	pr_info("Total guest execution time: %ld.%.9lds\n",

		ts_diff.tv_sec, ts_diff.tv_nsec);

	pr_info("Overall demand paging rate: %f pgs/sec\n",

tools/testing/selftests/kvm/include/test_util.h

+1 −0
Original line number Diff line number Diff line
@@ -64,5 +64,6 @@ int64_t timespec_to_ns(struct timespec ts); 
struct timespec timespec_add_ns(struct timespec ts, int64_t ns);

struct timespec timespec_add(struct timespec ts1, struct timespec ts2);

struct timespec timespec_sub(struct timespec ts1, struct timespec ts2);

struct timespec timespec_diff_now(struct timespec start);



#endif /* SELFTEST_KVM_TEST_UTIL_H */

tools/testing/selftests/kvm/lib/test_util.c

+13 −2
Original line number Diff line number Diff line
@@ -4,10 +4,13 @@ 
 *

 * Copyright (C) 2020, Google LLC.

 */

#include <stdlib.h>



#include <assert.h>

#include <ctype.h>

#include <limits.h>

#include <assert.h>

#include <stdlib.h>

#include <time.h>



#include "test_util.h"



/*
@@ -81,6 +84,14 @@ struct timespec timespec_sub(struct timespec ts1, struct timespec ts2) 
	return timespec_add_ns((struct timespec){0}, ns1 - ns2);

}



struct timespec timespec_diff_now(struct timespec start)

{

	struct timespec end;



	clock_gettime(CLOCK_MONOTONIC, &end);

	return timespec_sub(end, start);

}



void print_skip(const char *fmt, ...)

{

	va_list ap;