mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-30 15:44:13 +08:00
selftests: add basic posix timers selftests
Add some initial basic tests on a few posix timers interface such as setitimer() and timer_settime(). These simply check that expiration happens in a reasonable timeframe after expected elapsed clock time (user time, user + system time, real time, ...). This is helpful for finding basic breakages while hacking on this subsystem. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Stanislaw Gruszka <sgruszka@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Cc: Olivier Langlois <olivier@trillion01.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
parent
2473f3e7a9
commit
0bc4b0cf15
@ -6,6 +6,7 @@ TARGETS += memory-hotplug
|
||||
TARGETS += mqueue
|
||||
TARGETS += net
|
||||
TARGETS += ptrace
|
||||
TARGETS += timers
|
||||
TARGETS += vm
|
||||
|
||||
all:
|
||||
|
8
tools/testing/selftests/timers/Makefile
Normal file
8
tools/testing/selftests/timers/Makefile
Normal file
@ -0,0 +1,8 @@
|
||||
all:
|
||||
gcc posix_timers.c -o posix_timers -lrt
|
||||
|
||||
run_tests: all
|
||||
./posix_timers
|
||||
|
||||
clean:
|
||||
rm -f ./posix_timers
|
221
tools/testing/selftests/timers/posix_timers.c
Normal file
221
tools/testing/selftests/timers/posix_timers.c
Normal file
@ -0,0 +1,221 @@
|
||||
/*
|
||||
* Copyright (C) 2013 Red Hat, Inc., Frederic Weisbecker <fweisbec@redhat.com>
|
||||
*
|
||||
* Licensed under the terms of the GNU GPL License version 2
|
||||
*
|
||||
* Selftests for a few posix timers interface.
|
||||
*
|
||||
* Kernel loop code stolen from Steven Rostedt <srostedt@redhat.com>
|
||||
*/
|
||||
|
||||
#include <sys/time.h>
|
||||
#include <stdio.h>
|
||||
#include <signal.h>
|
||||
#include <unistd.h>
|
||||
#include <time.h>
|
||||
#include <pthread.h>
|
||||
|
||||
#define DELAY 2
|
||||
#define USECS_PER_SEC 1000000
|
||||
|
||||
static volatile int done;
|
||||
|
||||
/* Busy loop in userspace to elapse ITIMER_VIRTUAL */
|
||||
static void user_loop(void)
|
||||
{
|
||||
while (!done);
|
||||
}
|
||||
|
||||
/*
|
||||
* Try to spend as much time as possible in kernelspace
|
||||
* to elapse ITIMER_PROF.
|
||||
*/
|
||||
static void kernel_loop(void)
|
||||
{
|
||||
void *addr = sbrk(0);
|
||||
|
||||
while (!done) {
|
||||
brk(addr + 4096);
|
||||
brk(addr);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Sleep until ITIMER_REAL expiration.
|
||||
*/
|
||||
static void idle_loop(void)
|
||||
{
|
||||
pause();
|
||||
}
|
||||
|
||||
static void sig_handler(int nr)
|
||||
{
|
||||
done = 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Check the expected timer expiration matches the GTOD elapsed delta since
|
||||
* we armed the timer. Keep a 0.5 sec error margin due to various jitter.
|
||||
*/
|
||||
static int check_diff(struct timeval start, struct timeval end)
|
||||
{
|
||||
long long diff;
|
||||
|
||||
diff = end.tv_usec - start.tv_usec;
|
||||
diff += (end.tv_sec - start.tv_sec) * USECS_PER_SEC;
|
||||
|
||||
if (abs(diff - DELAY * USECS_PER_SEC) > USECS_PER_SEC / 2) {
|
||||
printf("Diff too high: %lld..", diff);
|
||||
return -1;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int check_itimer(int which)
|
||||
{
|
||||
int err;
|
||||
struct timeval start, end;
|
||||
struct itimerval val = {
|
||||
.it_value.tv_sec = DELAY,
|
||||
};
|
||||
|
||||
printf("Check itimer ");
|
||||
|
||||
if (which == ITIMER_VIRTUAL)
|
||||
printf("virtual... ");
|
||||
else if (which == ITIMER_PROF)
|
||||
printf("prof... ");
|
||||
else if (which == ITIMER_REAL)
|
||||
printf("real... ");
|
||||
|
||||
fflush(stdout);
|
||||
|
||||
done = 0;
|
||||
|
||||
if (which == ITIMER_VIRTUAL)
|
||||
signal(SIGVTALRM, sig_handler);
|
||||
else if (which == ITIMER_PROF)
|
||||
signal(SIGPROF, sig_handler);
|
||||
else if (which == ITIMER_REAL)
|
||||
signal(SIGALRM, sig_handler);
|
||||
|
||||
err = gettimeofday(&start, NULL);
|
||||
if (err < 0) {
|
||||
perror("Can't call gettimeofday()\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
err = setitimer(which, &val, NULL);
|
||||
if (err < 0) {
|
||||
perror("Can't set timer\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (which == ITIMER_VIRTUAL)
|
||||
user_loop();
|
||||
else if (which == ITIMER_PROF)
|
||||
kernel_loop();
|
||||
else if (which == ITIMER_REAL)
|
||||
idle_loop();
|
||||
|
||||
gettimeofday(&end, NULL);
|
||||
if (err < 0) {
|
||||
perror("Can't call gettimeofday()\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (!check_diff(start, end))
|
||||
printf("[OK]\n");
|
||||
else
|
||||
printf("[FAIL]\n");
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int check_timer_create(int which)
|
||||
{
|
||||
int err;
|
||||
timer_t id;
|
||||
struct timeval start, end;
|
||||
struct itimerspec val = {
|
||||
.it_value.tv_sec = DELAY,
|
||||
};
|
||||
|
||||
printf("Check timer_create() ");
|
||||
if (which == CLOCK_THREAD_CPUTIME_ID) {
|
||||
printf("per thread... ");
|
||||
} else if (which == CLOCK_PROCESS_CPUTIME_ID) {
|
||||
printf("per process... ");
|
||||
}
|
||||
fflush(stdout);
|
||||
|
||||
done = 0;
|
||||
timer_create(which, NULL, &id);
|
||||
if (err < 0) {
|
||||
perror("Can't create timer\n");
|
||||
return -1;
|
||||
}
|
||||
signal(SIGALRM, sig_handler);
|
||||
|
||||
err = gettimeofday(&start, NULL);
|
||||
if (err < 0) {
|
||||
perror("Can't call gettimeofday()\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
err = timer_settime(id, 0, &val, NULL);
|
||||
if (err < 0) {
|
||||
perror("Can't set timer\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
user_loop();
|
||||
|
||||
gettimeofday(&end, NULL);
|
||||
if (err < 0) {
|
||||
perror("Can't call gettimeofday()\n");
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (!check_diff(start, end))
|
||||
printf("[OK]\n");
|
||||
else
|
||||
printf("[FAIL]\n");
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int main(int argc, char **argv)
|
||||
{
|
||||
int err;
|
||||
|
||||
printf("Testing posix timers. False negative may happen on CPU execution \n");
|
||||
printf("based timers if other threads run on the CPU...\n");
|
||||
|
||||
if (check_itimer(ITIMER_VIRTUAL) < 0)
|
||||
return -1;
|
||||
|
||||
if (check_itimer(ITIMER_PROF) < 0)
|
||||
return -1;
|
||||
|
||||
if (check_itimer(ITIMER_REAL) < 0)
|
||||
return -1;
|
||||
|
||||
if (check_timer_create(CLOCK_THREAD_CPUTIME_ID) < 0)
|
||||
return -1;
|
||||
|
||||
/*
|
||||
* It's unfortunately hard to reliably test a timer expiration
|
||||
* on parallel multithread cputime. We could arm it to expire
|
||||
* on DELAY * nr_threads, with nr_threads busy looping, then wait
|
||||
* the normal DELAY since the time is elapsing nr_threads faster.
|
||||
* But for that we need to ensure we have real physical free CPUs
|
||||
* to ensure true parallelism. So test only one thread until we
|
||||
* find a better solution.
|
||||
*/
|
||||
if (check_timer_create(CLOCK_PROCESS_CPUTIME_ID) < 0)
|
||||
return -1;
|
||||
|
||||
return 0;
|
||||
}
|
Loading…
Reference in New Issue
Block a user