/* 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 #include #include #include #include #include #include #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(); } inux-foundation.org>2017-02-06 14:37:55 -0800 commit72df5eba704252e54b5b19395cb938f8bb55cab8 (patch) tree9b9dd6aa0cd3b6cda738de32dd05075e6e66bab1 /drivers/usb/mon parent396bf4cd835e62d70fad4a03a8963e61f19021f2 (diff)parentf9f96fc10c09ca16e336854c08bc1563eed97985 (diff)
Merge tag 'media/v4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab: "A few documentation fixes at CEC (with got promoted from staging for 4.10), and one fix on its core." * tag 'media/v4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: [media] cec: fix wrong last_la determination [media] cec-intro.rst: mention the v4l-utils package and CEC utilities [media] cec rst: remove "This API is not yet finalized" notice
Diffstat (limited to 'drivers/usb/mon')