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-rw-r--r--kernel/tools/testing/selftests/timers/set-timer-lat.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/kernel/tools/testing/selftests/timers/set-timer-lat.c b/kernel/tools/testing/selftests/timers/set-timer-lat.c
new file mode 100644
index 000000000..4fc98c5b0
--- /dev/null
+++ b/kernel/tools/testing/selftests/timers/set-timer-lat.c
@@ -0,0 +1,216 @@
+/* set_timer latency test
+ * John Stultz (john.stultz@linaro.org)
+ * (C) Copyright Linaro 2014
+ * Licensed under the GPLv2
+ *
+ * This test makes sure the set_timer api is correct
+ *
+ * To build:
+ * $ gcc set-timer-lat.c -o set-timer-lat -lrt
+ *
+ * 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, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ */
+
+
+#include <stdio.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <pthread.h>
+#ifdef KTEST
+#include "../kselftest.h"
+#else
+static inline int ksft_exit_pass(void)
+{
+ exit(0);
+}
+static inline int ksft_exit_fail(void)
+{
+ exit(1);
+}
+#endif
+
+#define CLOCK_REALTIME 0
+#define CLOCK_MONOTONIC 1
+#define CLOCK_PROCESS_CPUTIME_ID 2
+#define CLOCK_THREAD_CPUTIME_ID 3
+#define CLOCK_MONOTONIC_RAW 4
+#define CLOCK_REALTIME_COARSE 5
+#define CLOCK_MONOTONIC_COARSE 6
+#define CLOCK_BOOTTIME 7
+#define CLOCK_REALTIME_ALARM 8
+#define CLOCK_BOOTTIME_ALARM 9
+#define CLOCK_HWSPECIFIC 10
+#define CLOCK_TAI 11
+#define NR_CLOCKIDS 12
+
+
+#define NSEC_PER_SEC 1000000000ULL
+#define UNRESONABLE_LATENCY 40000000 /* 40ms in nanosecs */
+
+#define TIMER_SECS 1
+int alarmcount;
+int clock_id;
+struct timespec start_time;
+long long max_latency_ns;
+
+char *clockstring(int clockid)
+{
+ switch (clockid) {
+ case CLOCK_REALTIME:
+ return "CLOCK_REALTIME";
+ case CLOCK_MONOTONIC:
+ return "CLOCK_MONOTONIC";
+ case CLOCK_PROCESS_CPUTIME_ID:
+ return "CLOCK_PROCESS_CPUTIME_ID";
+ case CLOCK_THREAD_CPUTIME_ID:
+ return "CLOCK_THREAD_CPUTIME_ID";
+ case CLOCK_MONOTONIC_RAW:
+ return "CLOCK_MONOTONIC_RAW";
+ case CLOCK_REALTIME_COARSE:
+ return "CLOCK_REALTIME_COARSE";
+ case CLOCK_MONOTONIC_COARSE:
+ return "CLOCK_MONOTONIC_COARSE";
+ case CLOCK_BOOTTIME:
+ return "CLOCK_BOOTTIME";
+ case CLOCK_REALTIME_ALARM:
+ return "CLOCK_REALTIME_ALARM";
+ case CLOCK_BOOTTIME_ALARM:
+ return "CLOCK_BOOTTIME_ALARM";
+ case CLOCK_TAI:
+ return "CLOCK_TAI";
+ };
+ return "UNKNOWN_CLOCKID";
+}
+
+
+long long timespec_sub(struct timespec a, struct timespec b)
+{
+ long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;
+
+ ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
+ return ret;
+}
+
+
+void sigalarm(int signo)
+{
+ long long delta_ns;
+ struct timespec ts;
+
+ clock_gettime(clock_id, &ts);
+ alarmcount++;
+
+ delta_ns = timespec_sub(start_time, ts);
+ delta_ns -= NSEC_PER_SEC * TIMER_SECS * alarmcount;
+
+ if (delta_ns < 0)
+ printf("%s timer fired early: FAIL\n", clockstring(clock_id));
+
+ if (delta_ns > max_latency_ns)
+ max_latency_ns = delta_ns;
+}
+
+int do_timer(int clock_id, int flags)
+{
+ struct sigevent se;
+ timer_t tm1;
+ struct itimerspec its1, its2;
+ int err;
+
+ /* Set up timer: */
+ memset(&se, 0, sizeof(se));
+ se.sigev_notify = SIGEV_SIGNAL;
+ se.sigev_signo = SIGRTMAX;
+ se.sigev_value.sival_int = 0;
+
+ max_latency_ns = 0;
+ alarmcount = 0;
+
+ err = timer_create(clock_id, &se, &tm1);
+ if (err) {
+ if ((clock_id == CLOCK_REALTIME_ALARM) ||
+ (clock_id == CLOCK_BOOTTIME_ALARM)) {
+ printf("%-22s %s missing CAP_WAKE_ALARM? : [UNSUPPORTED]\n",
+ clockstring(clock_id),
+ flags ? "ABSTIME":"RELTIME");
+ return 0;
+ }
+ printf("%s - timer_create() failed\n", clockstring(clock_id));
+ return -1;
+ }
+
+ clock_gettime(clock_id, &start_time);
+ if (flags) {
+ its1.it_value = start_time;
+ its1.it_value.tv_sec += TIMER_SECS;
+ } else {
+ its1.it_value.tv_sec = TIMER_SECS;
+ its1.it_value.tv_nsec = 0;
+ }
+ its1.it_interval.tv_sec = TIMER_SECS;
+ its1.it_interval.tv_nsec = 0;
+
+ err = timer_settime(tm1, flags, &its1, &its2);
+ if (err) {
+ printf("%s - timer_settime() failed\n", clockstring(clock_id));
+ return -1;
+ }
+
+ while (alarmcount < 5)
+ sleep(1);
+
+ printf("%-22s %s max latency: %10lld ns : ",
+ clockstring(clock_id),
+ flags ? "ABSTIME":"RELTIME",
+ max_latency_ns);
+
+ timer_delete(tm1);
+ if (max_latency_ns < UNRESONABLE_LATENCY) {
+ printf("[OK]\n");
+ return 0;
+ }
+ printf("[FAILED]\n");
+ return -1;
+}
+
+int main(void)
+{
+ struct sigaction act;
+ int signum = SIGRTMAX;
+ int ret = 0;
+
+ /* Set up signal handler: */
+ sigfillset(&act.sa_mask);
+ act.sa_flags = 0;
+ act.sa_handler = sigalarm;
+ sigaction(signum, &act, NULL);
+
+ printf("Setting timers for every %i seconds\n", TIMER_SECS);
+ for (clock_id = 0; clock_id < NR_CLOCKIDS; clock_id++) {
+
+ if ((clock_id == CLOCK_PROCESS_CPUTIME_ID) ||
+ (clock_id == CLOCK_THREAD_CPUTIME_ID) ||
+ (clock_id == CLOCK_MONOTONIC_RAW) ||
+ (clock_id == CLOCK_REALTIME_COARSE) ||
+ (clock_id == CLOCK_MONOTONIC_COARSE) ||
+ (clock_id == CLOCK_HWSPECIFIC))
+ continue;
+
+ ret |= do_timer(clock_id, TIMER_ABSTIME);
+ ret |= do_timer(clock_id, 0);
+ }
+ if (ret)
+ return ksft_exit_fail();
+ return ksft_exit_pass();
+}