/******************************************************************************
*
* Copyright (C) 2007-2009 Steven Rostedt <srostedt@redhat.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License (not later!)
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* NAME
* rt-migrate-test.c
*
* DESCRIPTION
* This test makes sure that all the high prio tasks that are in the
* running state are actually running on a CPU if it can.
** Steps:
* - Creates N+1 threads with lower real time priorities.
* Where N is the number of CPUs in the system.
* - If the thread is high priority, and if a CPU is available, the
* thread runs on that CPU.
* - The thread records the start time and the number of ticks in the run
* interval.
* - The output indicates if lower prio task is quicker than higher
* priority task.
*
* USAGE:
* Use run_auto.sh in the current directory to build and run the test.
*
* AUTHOR
* Steven Rostedt <srostedt@redhat.com>
*
* HISTORY
* 30 July, 2009: Initial version by Steven Rostedt
* 11 Aug, 2009: Converted the coding style to the one used by the realtime
* testcases by Kiran Prakash
*
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <stdarg.h>
#include <unistd.h>
#include <ctype.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/time.h>
#include <linux/unistd.h>
#include <sys/syscall.h>
#include <errno.h>
#include <sched.h>
#include <pthread.h>
#include <librttest.h>
#include <libstats.h>
#define gettid() syscall(__NR_gettid)
#define VERSION_STRING "V 0.4LTP"
int nr_tasks;
int lfd;
int numcpus;
static int mark_fd = -1;
static __thread char buff[BUFSIZ + 1];
static void setup_ftrace_marker(void)
{
struct stat st;
char *files[] = {
"/sys/kernel/debug/tracing/trace_marker",
"/debug/tracing/trace_marker",
"/debugfs/tracing/trace_marker",
};
int ret;
int i;
for (i = 0; i < (sizeof(files) / sizeof(char *)); i++) {
ret = stat(files[i], &st);
if (ret >= 0)
goto found;
}
/* todo, check mounts system */
return;
found:
mark_fd = open(files[i], O_WRONLY);
}
static void ftrace_write(const char *fmt, ...)
{
va_list ap;
int n;
if (mark_fd < 0)
return;
va_start(ap, fmt);
n = vsnprintf(buff, BUFSIZ, fmt, ap);
va_end(ap);
/*
* This doesn't return any valid vs invalid exit codes, so printing out
* a perror to warn the end-user of an issue is sufficient.
*/
if (write(mark_fd, buff, n) < 0) {
perror("write");
}
}
#define INTERVAL 100ULL * NS_PER_MS
#define RUN_INTERVAL 20ULL * NS_PER_MS
#define NR_RUNS 50
#define PRIO_START 2
/* 1 millisec off */
#define MAX_ERR 1000 * NS_PER_US
#define PROGRESS_CHARS 70
static unsigned long long interval = INTERVAL;
static unsigned long long run_interval = RUN_INTERVAL;
static unsigned long long max_err = MAX_ERR;
static int nr_runs = NR_RUNS;
static int prio_start = PRIO_START;
static int check = 1;
static int stop;
static unsigned long long now;
static int done;
static int loop;
static pthread_barrier_t start_barrier;
static pthread_barrier_t end_barrier;
stats_container_t *intervals;
stats_container_t *intervals_length;
stats_container_t *intervals_loops;
static long *thread_pids;
static void print_progress_bar(int percent)
{
int i;
int p;
if (percent > 100)
percent = 100;
/* Use stderr, so we don't capture it */
putc('\r', stderr);
putc('|', stderr);
for (i = 0; i < PROGRESS_CHARS; i++)
putc(' ', stderr);
putc('|', stderr);
putc('\r', stderr);
putc('|', stderr);
p = PROGRESS_CHARS * percent / 100;
for (i = 0; i < p; i++)
putc('-', stderr);
fflush(stderr);
}
static void usage()
{
rt_help();
printf("Usage:\n"
"-a priority Priority of the threads"
"-r time Run time (ms) to busy loop the threads (20)\n"
"-t time Sleep time (ms) between intervals (100)\n"
"-e time Max allowed error (microsecs)\n"
"-l loops Number of iterations to run (50)\n");
}
/*
int rt_init(const char *options, int (*parse_arg)(int option, char *value),
int argc, char *argv[]);
*/
static int parse_args(int c, char *v)
{
int handled = 1;
switch (c) {
case 'a':
prio_start = atoi(v);
break;
case 'r':
run_interval = atoi(v);
break;
case 't':
interval = atoi(v);
break;
case 'l':
nr_runs = atoi(v);
break;
case 'e':
max_err = atoi(v) * NS_PER_US;
break;
case '?':
case 'h':
usage();
handled = 0;
}
return handled;
}
static void record_time(int id, unsigned long long time, unsigned long l)
{
unsigned long long ltime;
stats_record_t rec;
if (loop >= nr_runs)
return;
time -= now;
ltime = rt_gettime() / NS_PER_US;
ltime -= now;
rec.x = loop;
rec.y = time;
stats_container_append(&intervals[id], rec);
rec.x = loop;
rec.y = ltime;
stats_container_append(&intervals_length[id], rec);
rec.x = loop;
rec.y = l;
stats_container_append(&intervals_loops[id], rec);
}
static void print_results(void)
{
int i;
int t;
unsigned long long tasks_max[nr_tasks];
unsigned long long tasks_min[nr_tasks];
unsigned long long tasks_avg[nr_tasks];
memset(tasks_max, 0, sizeof(tasks_max[0]) * nr_tasks);
memset(tasks_min, 0xff, sizeof(tasks_min[0]) * nr_tasks);
memset(tasks_avg, 0, sizeof(tasks_avg[0]) * nr_tasks);
printf("Iter: ");
for (t = 0; t < nr_tasks; t++)
printf("%6d ", t);
printf("\n");
for (t = 0; t < nr_tasks; t++) {
tasks_max[t] = stats_max(&intervals[t]);
tasks_min[t] = stats_min(&intervals[t]);
tasks_avg[t] = stats_avg(&intervals[t]);
}
for (i = 0; i < nr_runs; i++) {
printf("%4d: ", i);
for (t = 0; t < nr_tasks; t++)
printf("%6ld ", intervals[t].records[i].y);
printf("\n");
printf(" len: ");
for (t = 0; t < nr_tasks; t++)
printf("%6ld ", intervals_length[t].records[i].y);
printf("\n");
printf(" loops: ");
for (t = 0; t < nr_tasks; t++)
printf("%6ld ", intervals_loops[t].records[i].y);
printf("\n");
printf("\n");
}
printf("Parent pid: %d\n", getpid());
for (t = 0; t < nr_tasks; t++) {
printf(" Task %d (prio %d) (pid %ld):\n", t, t + prio_start,
thread_pids[t]);
printf(" Max: %lld us\n", tasks_max[t]);
printf(" Min: %lld us\n", tasks_min[t]);
printf(" Tot: %lld us\n", tasks_avg[t] * nr_runs);
printf(" Avg: %lld us\n", tasks_avg[t]);
printf("\n");
}
printf(" Result: %s\n", (check < 0) ? "FAIL" : "PASS");
}
static unsigned long busy_loop(unsigned long long start_time)
{
unsigned long long time;
unsigned long l = 0;
do {
l++;
time = rt_gettime();
} while ((time - start_time) < RUN_INTERVAL);
return l;
}
void *start_task(void *data)
{
struct thread *thr = (struct thread *)data;
long id = (long)thr->arg;
thread_pids[id] = gettid();
unsigned long long start_time;
int ret;
int high = 0;
cpu_set_t cpumask;
cpu_set_t save_cpumask;
int cpu = 0;
unsigned long l;
long pid;
ret = sched_getaffinity(0, sizeof(save_cpumask), &save_cpumask);
if (ret < 0)
debug(DBG_ERR, "sched_getaffinity failed: %s\n", strerror(ret));
pid = gettid();
/* Check if we are the highest prio task */
if (id == nr_tasks - 1)
high = 1;
while (!done) {
if (high) {
/* rotate around the CPUS */
if (!CPU_ISSET(cpu, &save_cpumask))
cpu = 0;
CPU_ZERO(&cpumask);
CPU_SET(cpu, &cpumask);
cpu++;
sched_setaffinity(0, sizeof(cpumask), &cpumask);
}
pthread_barrier_wait(&start_barrier);
start_time = rt_gettime();
ftrace_write("Thread %d: started %lld diff %lld\n",
pid, start_time, start_time - now);
l = busy_loop(start_time);
record_time(id, start_time / NS_PER_US, l);
pthread_barrier_wait(&end_barrier);
}
return (void *)pid;
}
static int check_times(int l)
{
int i;
unsigned long long last;
unsigned long long last_loops;
unsigned long long last_length;
for (i = 0; i < nr_tasks; i++) {
if (i && last < intervals[i].records[l].y &&
((intervals[i].records[l].y - last) > max_err)) {
/*
* May be a false positive.
* Make sure that we did more loops
* our start is before the end
* and the end should be tested.
*/
if (intervals_loops[i].records[l].y < last_loops ||
intervals[i].records[l].y > last_length ||
(intervals_length[i].records[l].y > last_length &&
intervals_length[i].records[l].y - last_length >
max_err)) {
check = -1;
return 1;
}
}
last = intervals[i].records[l].y;
last_loops = intervals_loops[i].records[l].y;
last_length = intervals_length[i].records[l].y;
}
return 0;
}
static void stop_log(int sig)
{
stop = 1;
}
int main(int argc, char **argv)
{
pthread_t *threads;
long i;
int ret;
struct timespec intv;
struct sched_param param;
rt_init("a:r:t:e:l:h:", parse_args, argc, argv);
signal(SIGINT, stop_log);
if (argc >= (optind + 1))
nr_tasks = atoi(argv[optind]);
else {
numcpus = sysconf(_SC_NPROCESSORS_ONLN);
nr_tasks = numcpus + 1;
}
intervals = malloc(sizeof(stats_container_t) * nr_tasks);
if (!intervals)
debug(DBG_ERR, "malloc failed\n");
memset(intervals, 0, sizeof(stats_container_t) * nr_tasks);
intervals_length = malloc(sizeof(stats_container_t) * nr_tasks);
if (!intervals_length)
debug(DBG_ERR, "malloc failed\n");
memset(intervals_length, 0, sizeof(stats_container_t) * nr_tasks);
if (!intervals_loops)
debug(DBG_ERR, "malloc failed\n");
intervals_loops = malloc(sizeof(stats_container_t) * nr_tasks);
memset(intervals_loops, 0, sizeof(stats_container_t) * nr_tasks);
threads = malloc(sizeof(*threads) * nr_tasks);
if (!threads)
debug(DBG_ERR, "malloc failed\n");
memset(threads, 0, sizeof(*threads) * nr_tasks);
ret = pthread_barrier_init(&start_barrier, NULL, nr_tasks + 1);
ret = pthread_barrier_init(&end_barrier, NULL, nr_tasks + 1);
if (ret < 0)
debug(DBG_ERR, "pthread_barrier_init failed: %s\n",
strerror(ret));
for (i = 0; i < nr_tasks; i++) {
stats_container_init(&intervals[i], nr_runs);
stats_container_init(&intervals_length[i], nr_runs);
stats_container_init(&intervals_loops[i], nr_runs);
}
thread_pids = malloc(sizeof(long) * nr_tasks);
if (!thread_pids)
debug(DBG_ERR, "malloc thread_pids failed\n");
for (i = 0; i < nr_tasks; i++) {
threads[i] = create_fifo_thread(start_task, (void *)i,
prio_start + i);
}
/*
* Progress bar uses stderr to let users see it when
* redirecting output. So we convert stderr to use line
* buffering so the progress bar doesn't flicker.
*/
setlinebuf(stderr);
/* up our prio above all tasks */
memset(¶m, 0, sizeof(param));
param.sched_priority = nr_tasks + prio_start;
if (sched_setscheduler(0, SCHED_FIFO, ¶m))
debug(DBG_WARN, "Warning, can't set priority of"
"main thread !\n");
intv.tv_sec = INTERVAL / NS_PER_SEC;
intv.tv_nsec = INTERVAL % (1 * NS_PER_SEC);
print_progress_bar(0);
setup_ftrace_marker();
for (loop = 0; loop < nr_runs; loop++) {
unsigned long long end;
now = rt_gettime() / NS_PER_US;
ftrace_write("Loop %d now=%lld\n", loop, now);
pthread_barrier_wait(&start_barrier);
ftrace_write("All running!!!\n");
rt_nanosleep(intv.tv_nsec);
print_progress_bar((loop * 100) / nr_runs);
end = rt_gettime() / NS_PER_US;
ftrace_write("Loop %d end now=%lld diff=%lld\n",
loop, end, end - now);
ret = pthread_barrier_wait(&end_barrier);
if (stop || (check && check_times(loop))) {
loop++;
nr_runs = loop;
break;
}
}
putc('\n', stderr);
pthread_barrier_wait(&start_barrier);
done = 1;
pthread_barrier_wait(&end_barrier);
join_threads();
print_results();
if (stop) {
/*
* We use this test in bash while loops
* So if we hit Ctrl-C then let the while
* loop know to break.
*/
if (check < 0)
exit(-1);
else
exit(1);
}
if (check < 0)
exit(-1);
else
exit(0);
}