| 1 | // SPDX-License-Identifier: GPL-3.0-or-later |
| 2 | |
| 3 | #include "../libnetdata.h" |
| 4 | |
| 5 | // defaults are for compatibility |
| 6 | // call clocks_init() once, to optimize these default settings |
| 7 | static clockid_t clock_boottime_to_use = CLOCK_MONOTONIC; |
| 8 | static clockid_t clock_monotonic_to_use = CLOCK_MONOTONIC; |
| 9 | |
| 10 | // the default clock resolution is 1ms |
| 11 | #define DEFAULT_CLOCK_RESOLUTION_UT ((usec_t)0 * USEC_PER_SEC + (usec_t)1 * USEC_PER_MS) |
| 12 | |
| 13 | // the max clock resolution is 10ms |
| 14 | #define MAX_CLOCK_RESOLUTION_UT ((usec_t)0 * USEC_PER_SEC + (usec_t)10 * USEC_PER_MS) |
| 15 | |
| 16 | usec_t clock_monotonic_resolution = DEFAULT_CLOCK_RESOLUTION_UT; |
| 17 | usec_t clock_realtime_resolution = DEFAULT_CLOCK_RESOLUTION_UT; |
| 18 | |
| 19 | #ifndef HAVE_CLOCK_GETTIME |
| 20 | inline int clock_gettime(clockid_t clk_id __maybe_unused, struct timespec *ts) { |
| 21 | struct timeval tv; |
| 22 | if(unlikely(gettimeofday(&tv, NULL) == -1)) { |
| 23 | netdata_log_error("gettimeofday() failed."); |
| 24 | return -1; |
| 25 | } |
| 26 | ts->tv_sec = tv.tv_sec; |
| 27 | ts->tv_nsec = (long)((tv.tv_usec % USEC_PER_SEC) * NSEC_PER_USEC); |
| 28 | return 0; |
| 29 | } |
| 30 | #endif |
| 31 | |
| 32 | // Similar to CLOCK_MONOTONIC, but provides access to a raw hardware-based time that is not subject to NTP adjustments |
| 33 | // or the incremental adjustments performed by adjtime(3). This clock does not count time that the system is suspended |
| 34 | |
| 35 | static void test_clock_monotonic_raw(void) { |
| 36 | #ifdef CLOCK_MONOTONIC_RAW |
| 37 | struct timespec ts; |
| 38 | if(clock_gettime(CLOCK_MONOTONIC_RAW, &ts) == -1 && errno == EINVAL) |
| 39 | clock_monotonic_to_use = CLOCK_MONOTONIC; |
| 40 | else |
| 41 | clock_monotonic_to_use = CLOCK_MONOTONIC_RAW; |
| 42 | #else |
| 43 | clock_monotonic_to_use = CLOCK_MONOTONIC; |
| 44 | #endif |
| 45 | } |
| 46 | |
| 47 | // When running a binary with CLOCK_BOOTTIME defined on a system with a linux kernel older than Linux 2.6.39 the |
| 48 | // clock_gettime(2) system call fails with EINVAL. In that case it must fall-back to CLOCK_MONOTONIC. |
| 49 | |
| 50 | static void test_clock_boottime(void) { |
| 51 | struct timespec ts; |
| 52 | if(clock_gettime(CLOCK_BOOTTIME, &ts) == -1 && errno == EINVAL) |
| 53 | clock_boottime_to_use = clock_monotonic_to_use; |
| 54 | else |
| 55 | clock_boottime_to_use = CLOCK_BOOTTIME; |
| 56 | } |
| 57 | |
| 58 | static usec_t get_clock_resolution(clockid_t clock) { |
| 59 | struct timespec ts = { 0 }; |
| 60 | |
| 61 | if(clock_getres(clock, &ts) == 0) { |
| 62 | usec_t ret = (usec_t)ts.tv_sec * USEC_PER_SEC + (usec_t)ts.tv_nsec / NSEC_PER_USEC; |
| 63 | if(!ret && ts.tv_nsec > 0 && ts.tv_nsec < (long int)NSEC_PER_USEC) |
| 64 | return (usec_t)1; |
| 65 | |
| 66 | else if(ret > MAX_CLOCK_RESOLUTION_UT) { |
| 67 | nd_log(NDLS_DAEMON, NDLP_ERR, "clock_getres(%d) returned %"PRIu64" usec is out of range, using defaults for clock resolution.", (int)clock, ret); |
| 68 | return DEFAULT_CLOCK_RESOLUTION_UT; |
| 69 | } |
| 70 | |
| 71 | return ret; |
| 72 | } |
| 73 | else { |
| 74 | nd_log(NDLS_DAEMON, NDLP_ERR, "clock_getres(%d) failed, using defaults for clock resolution.", (int)clock); |
| 75 | return DEFAULT_CLOCK_RESOLUTION_UT; |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | // perform any initializations required for clocks |
| 80 | |
| 81 | static __attribute__((constructor)) void clocks_init(void) { |
| 82 | os_get_system_HZ(); |
| 83 | |
| 84 | // monotonic raw has to be tested before boottime |
| 85 | test_clock_monotonic_raw(); |
| 86 | |
| 87 | // boottime has to be tested after monotonic coarse |
| 88 | test_clock_boottime(); |
| 89 | |
| 90 | clock_monotonic_resolution = get_clock_resolution(clock_monotonic_to_use); |
| 91 | clock_realtime_resolution = get_clock_resolution(CLOCK_REALTIME); |
| 92 | |
| 93 | #if defined(OS_WINDOWS) |
| 94 | timeBeginPeriod(1); |
| 95 | clock_monotonic_resolution = 1 * USEC_PER_MS; |
| 96 | clock_realtime_resolution = 1 * USEC_PER_MS; |
| 97 | #endif |
| 98 | } |
| 99 | |
| 100 | static __attribute__((destructor)) void clocks_fin(void) { |
| 101 | #if defined(OS_WINDOWS) |
| 102 | timeEndPeriod(1); |
| 103 | #endif |
| 104 | } |
| 105 | |
| 106 | ALWAYS_INLINE time_t now_sec(clockid_t clk_id) { |
| 107 | struct timespec ts; |
| 108 | if(unlikely(clock_gettime(clk_id, &ts) == -1)) { |
| 109 | netdata_log_error("clock_gettime(%ld, ×pec) failed.", (long int)clk_id); |
| 110 | return 0; |
| 111 | } |
| 112 | return ts.tv_sec; |
| 113 | } |
| 114 | |
| 115 | ALWAYS_INLINE usec_t now_usec(clockid_t clk_id) { |
| 116 | struct timespec ts; |
| 117 | if(unlikely(clock_gettime(clk_id, &ts) == -1)) { |
| 118 | netdata_log_error("clock_gettime(%ld, ×pec) failed.", (long int)clk_id); |
| 119 | return 0; |
| 120 | } |
| 121 | return (usec_t)ts.tv_sec * USEC_PER_SEC + (usec_t)(ts.tv_nsec % NSEC_PER_SEC) / NSEC_PER_USEC; |
| 122 | } |
| 123 | |
| 124 | ALWAYS_INLINE int now_timeval(clockid_t clk_id, struct timeval *tv) { |
| 125 | struct timespec ts; |
| 126 | |
| 127 | if(unlikely(clock_gettime(clk_id, &ts) == -1)) { |
| 128 | netdata_log_error("clock_gettime(%ld, ×pec) failed.", (long int)clk_id); |
| 129 | tv->tv_sec = 0; |
| 130 | tv->tv_usec = 0; |
| 131 | return -1; |
| 132 | } |
| 133 | |
| 134 | tv->tv_sec = ts.tv_sec; |
| 135 | tv->tv_usec = (suseconds_t)((ts.tv_nsec % NSEC_PER_SEC) / NSEC_PER_USEC); |
| 136 | return 0; |
| 137 | } |
| 138 | |
| 139 | ALWAYS_INLINE time_t now_realtime_sec(void) { |
| 140 | return now_sec(CLOCK_REALTIME); |
| 141 | } |
| 142 | |
| 143 | ALWAYS_INLINE msec_t now_realtime_msec(void) { |
| 144 | return now_usec(CLOCK_REALTIME) / USEC_PER_MS; |
| 145 | } |
| 146 | |
| 147 | ALWAYS_INLINE usec_t now_realtime_usec(void) { |
| 148 | return now_usec(CLOCK_REALTIME); |
| 149 | } |
| 150 | |
| 151 | ALWAYS_INLINE int now_realtime_timeval(struct timeval *tv) { |
| 152 | return now_timeval(CLOCK_REALTIME, tv); |
| 153 | } |
| 154 | |
| 155 | ALWAYS_INLINE time_t now_monotonic_sec(void) { |
| 156 | return now_sec(clock_monotonic_to_use); |
| 157 | } |
| 158 | |
| 159 | ALWAYS_INLINE usec_t now_monotonic_usec(void) { |
| 160 | return now_usec(clock_monotonic_to_use); |
| 161 | } |
| 162 | |
| 163 | ALWAYS_INLINE int now_monotonic_timeval(struct timeval *tv) { |
| 164 | return now_timeval(clock_monotonic_to_use, tv); |
| 165 | } |
| 166 | |
| 167 | ALWAYS_INLINE time_t now_monotonic_high_precision_sec(void) { |
| 168 | return now_sec(CLOCK_MONOTONIC); |
| 169 | } |
| 170 | |
| 171 | ALWAYS_INLINE usec_t now_monotonic_high_precision_usec(void) { |
| 172 | return now_usec(CLOCK_MONOTONIC); |
| 173 | } |
| 174 | |
| 175 | ALWAYS_INLINE int now_monotonic_high_precision_timeval(struct timeval *tv) { |
| 176 | return now_timeval(CLOCK_MONOTONIC, tv); |
| 177 | } |
| 178 | |
| 179 | ALWAYS_INLINE time_t now_boottime_sec(void) { |
| 180 | return now_sec(clock_boottime_to_use); |
| 181 | } |
| 182 | |
| 183 | ALWAYS_INLINE usec_t now_boottime_usec(void) { |
| 184 | return now_usec(clock_boottime_to_use); |
| 185 | } |
| 186 | |
| 187 | ALWAYS_INLINE int now_boottime_timeval(struct timeval *tv) { |
| 188 | return now_timeval(clock_boottime_to_use, tv); |
| 189 | } |
| 190 | |
| 191 | ALWAYS_INLINE usec_t timeval_usec(struct timeval *tv) { |
| 192 | return (usec_t)tv->tv_sec * USEC_PER_SEC + (tv->tv_usec % USEC_PER_SEC); |
| 193 | } |
| 194 | |
| 195 | ALWAYS_INLINE msec_t timeval_msec(struct timeval *tv) { |
| 196 | return (msec_t)tv->tv_sec * MSEC_PER_SEC + ((tv->tv_usec % USEC_PER_SEC) / MSEC_PER_SEC); |
| 197 | } |
| 198 | |
| 199 | ALWAYS_INLINE susec_t dt_usec_signed(struct timeval *now, struct timeval *old) { |
| 200 | usec_t ts1 = timeval_usec(now); |
| 201 | usec_t ts2 = timeval_usec(old); |
| 202 | |
| 203 | if(likely(ts1 >= ts2)) return (susec_t)(ts1 - ts2); |
| 204 | return -((susec_t)(ts2 - ts1)); |
| 205 | } |
| 206 | |
| 207 | ALWAYS_INLINE usec_t dt_usec(struct timeval *now, struct timeval *old) { |
| 208 | usec_t ts1 = timeval_usec(now); |
| 209 | usec_t ts2 = timeval_usec(old); |
| 210 | return (ts1 > ts2) ? (ts1 - ts2) : (ts2 - ts1); |
| 211 | } |
| 212 | |
| 213 | #ifdef __linux__ |
| 214 | void sleep_to_absolute_time(usec_t usec) { |
| 215 | static int einval_printed = 0, enotsup_printed = 0, eunknown_printed = 0; |
| 216 | clockid_t clock = CLOCK_REALTIME; |
| 217 | |
| 218 | struct timespec req = { |
| 219 | .tv_sec = (time_t)(usec / USEC_PER_SEC), |
| 220 | .tv_nsec = (suseconds_t)((usec % USEC_PER_SEC) * NSEC_PER_USEC) |
| 221 | }; |
| 222 | |
| 223 | errno = 0; |
| 224 | int ret = 0; |
| 225 | while( (ret = clock_nanosleep(clock, TIMER_ABSTIME, &req, NULL)) != 0 ) { |
| 226 | if(ret == EINTR) { |
| 227 | errno = 0; |
| 228 | continue; |
| 229 | } |
| 230 | else { |
| 231 | if (ret == EINVAL) { |
| 232 | if (!einval_printed) { |
| 233 | einval_printed++; |
| 234 | netdata_log_error("Invalid time given to clock_nanosleep(): clockid = %d, tv_sec = %lld, tv_nsec = %ld", |
| 235 | clock, |
| 236 | (long long)req.tv_sec, |
| 237 | req.tv_nsec); |
| 238 | } |
| 239 | } else if (ret == ENOTSUP) { |
| 240 | if (!enotsup_printed) { |
| 241 | enotsup_printed++; |
| 242 | netdata_log_error("Invalid clock id given to clock_nanosleep(): clockid = %d, tv_sec = %lld, tv_nsec = %ld", |
| 243 | clock, |
| 244 | (long long)req.tv_sec, |
| 245 | req.tv_nsec); |
| 246 | } |
| 247 | } else { |
| 248 | if (!eunknown_printed) { |
| 249 | eunknown_printed++; |
| 250 | netdata_log_error("Unknown return value %d from clock_nanosleep(): clockid = %d, tv_sec = %lld, tv_nsec = %ld", |
| 251 | ret, |
| 252 | clock, |
| 253 | (long long)req.tv_sec, |
| 254 | req.tv_nsec); |
| 255 | } |
| 256 | } |
| 257 | sleep_usec(usec); |
| 258 | } |
| 259 | } |
| 260 | } |
| 261 | #endif |
| 262 | |
| 263 | #define HEARTBEAT_MIN_OFFSET_UT (150 * USEC_PER_MS) |
| 264 | #define HEARTBEAT_RANDOM_OFFSET_UT (350 * USEC_PER_MS) |
| 265 | |
| 266 | #define HEARTBEAT_ALIGNMENT_STATISTICS_SIZE 20 |
| 267 | static SPINLOCK heartbeat_alignment_spinlock = SPINLOCK_INITIALIZER; |
| 268 | static size_t heartbeat_alignment_id = 0; |
| 269 | |
| 270 | struct heartbeat_thread_statistics { |
| 271 | pid_t tid; |
| 272 | size_t sequence; |
| 273 | usec_t dt; |
| 274 | usec_t randomness; |
| 275 | }; |
| 276 | static struct heartbeat_thread_statistics heartbeat_alignment_values[HEARTBEAT_ALIGNMENT_STATISTICS_SIZE] = { 0 }; |
| 277 | |
| 278 | void heartbeat_statistics(usec_t *min_ptr, usec_t *max_ptr, usec_t *average_ptr, size_t *count_ptr) { |
| 279 | struct heartbeat_thread_statistics current[HEARTBEAT_ALIGNMENT_STATISTICS_SIZE]; |
| 280 | static struct heartbeat_thread_statistics old[HEARTBEAT_ALIGNMENT_STATISTICS_SIZE] = { 0 }; |
| 281 | |
| 282 | memcpy(current, heartbeat_alignment_values, sizeof(struct heartbeat_thread_statistics) * HEARTBEAT_ALIGNMENT_STATISTICS_SIZE); |
| 283 | |
| 284 | usec_t min = 0, max = 0, total = 0, average = 0; |
| 285 | size_t i, count = 0; |
| 286 | for(i = 0; i < HEARTBEAT_ALIGNMENT_STATISTICS_SIZE ;i++) { |
| 287 | if(current[i].sequence == old[i].sequence) continue; |
| 288 | usec_t value = current[i].dt - old[i].dt; |
| 289 | |
| 290 | if(!count) { |
| 291 | min = max = total = value; |
| 292 | count = 1; |
| 293 | } |
| 294 | else { |
| 295 | total += value; |
| 296 | if(value < min) min = value; |
| 297 | if(value > max) max = value; |
| 298 | count++; |
| 299 | } |
| 300 | } |
| 301 | if(count) |
| 302 | average = total / count; |
| 303 | |
| 304 | if(min_ptr) *min_ptr = min; |
| 305 | if(max_ptr) *max_ptr = max; |
| 306 | if(average_ptr) *average_ptr = average; |
| 307 | if(count_ptr) *count_ptr = count; |
| 308 | |
| 309 | memcpy(old, current, sizeof(struct heartbeat_thread_statistics) * HEARTBEAT_ALIGNMENT_STATISTICS_SIZE); |
| 310 | } |
| 311 | |
| 312 | static XXH64_hash_t heartbeat_hash(usec_t step, size_t statistics_id) { |
| 313 | struct { |
| 314 | usec_t step; |
| 315 | pid_t pid; |
| 316 | pid_t tid; |
| 317 | usec_t now_ut; |
| 318 | size_t statistics_id; |
| 319 | char tag[ND_THREAD_TAG_MAX + 1]; |
| 320 | } key = { |
| 321 | .step = step, |
| 322 | .pid = getpid(), |
| 323 | .tid = os_gettid(), |
| 324 | .now_ut = now_realtime_usec(), |
| 325 | .statistics_id = statistics_id, |
| 326 | }; |
| 327 | strncpyz(key.tag, nd_thread_tag(), sizeof(key.tag) - 1); |
| 328 | return XXH3_64bits(&key, sizeof(key)); |
| 329 | } |
| 330 | |
| 331 | static usec_t heartbeat_randomness(XXH64_hash_t hash) { |
| 332 | usec_t offset_ut = HEARTBEAT_MIN_OFFSET_UT + (hash % HEARTBEAT_RANDOM_OFFSET_UT); |
| 333 | |
| 334 | // A zero HZ value turns heartbeat initialization into SIGFPE. |
| 335 | usec_t hz = system_hz ? (usec_t)system_hz : 100; |
| 336 | |
| 337 | // Calculate the scheduler tick interval in microseconds. |
| 338 | usec_t scheduler_step_ut = USEC_PER_SEC / hz; |
| 339 | if(scheduler_step_ut > 10 * USEC_PER_MS) |
| 340 | scheduler_step_ut = 10 * USEC_PER_MS; |
| 341 | else if(unlikely(!scheduler_step_ut)) |
| 342 | scheduler_step_ut = 1; |
| 343 | |
| 344 | // if the offset is close to the scheduler tick, move it away from it |
| 345 | if(offset_ut % scheduler_step_ut < scheduler_step_ut / 4) |
| 346 | offset_ut += scheduler_step_ut / 4; |
| 347 | |
| 348 | return offset_ut; |
| 349 | } |
| 350 | |
| 351 | inline void heartbeat_init(heartbeat_t *hb, usec_t step) { |
| 352 | if(!step) step = USEC_PER_SEC; |
| 353 | |
| 354 | spinlock_lock(&heartbeat_alignment_spinlock); |
| 355 | hb->statistics_id = heartbeat_alignment_id; |
| 356 | heartbeat_alignment_id++; |
| 357 | spinlock_unlock(&heartbeat_alignment_spinlock); |
| 358 | |
| 359 | hb->step = step; |
| 360 | hb->realtime = 0ULL; |
| 361 | hb->hash = heartbeat_hash(hb->step, hb->statistics_id); |
| 362 | hb->randomness = heartbeat_randomness(hb->hash); |
| 363 | |
| 364 | if(hb->statistics_id < HEARTBEAT_ALIGNMENT_STATISTICS_SIZE) { |
| 365 | heartbeat_alignment_values[hb->statistics_id].dt = 0; |
| 366 | heartbeat_alignment_values[hb->statistics_id].sequence = 0; |
| 367 | heartbeat_alignment_values[hb->statistics_id].randomness = hb->randomness; |
| 368 | heartbeat_alignment_values[hb->statistics_id].tid = os_gettid(); |
| 369 | } |
| 370 | } |
| 371 | |
| 372 | // waits for the next heartbeat |
| 373 | // it waits using the monotonic clock |
| 374 | // it returns the dt using the realtime clock |
| 375 | |
| 376 | usec_t heartbeat_next(heartbeat_t *hb) { |
| 377 | usec_t tick = hb->step; |
| 378 | |
| 379 | usec_t dt; |
| 380 | usec_t now = now_realtime_usec(); |
| 381 | usec_t next = now - (now % tick) + tick + hb->randomness; |
| 382 | |
| 383 | // align the next time we want to the clock resolution |
| 384 | if(next % clock_realtime_resolution) |
| 385 | next = next - (next % clock_realtime_resolution) + clock_realtime_resolution; |
| 386 | |
| 387 | // sleep_usec() has a loop to guarantee we will sleep for at least the requested time. |
| 388 | // According to the specs, when we sleep for a relative time, clock adjustments should |
| 389 | // not affect the duration we sleep. |
| 390 | sleep_usec_with_now(next - now, now); |
| 391 | spinlock_lock(&heartbeat_alignment_spinlock); |
| 392 | now = now_realtime_usec(); |
| 393 | spinlock_unlock(&heartbeat_alignment_spinlock); |
| 394 | |
| 395 | dt = now - hb->realtime; |
| 396 | |
| 397 | if(hb->statistics_id < HEARTBEAT_ALIGNMENT_STATISTICS_SIZE) { |
| 398 | heartbeat_alignment_values[hb->statistics_id].dt += now - next; |
| 399 | heartbeat_alignment_values[hb->statistics_id].sequence++; |
| 400 | } |
| 401 | |
| 402 | if(unlikely(now < next)) { |
| 403 | errno_clear(); |
| 404 | nd_log_limit_static_global_var(erl, 10, 0); |
| 405 | nd_log_limit(&erl, NDLS_DAEMON, NDLP_NOTICE, |
| 406 | "heartbeat clock: woke up %"PRIu64" microseconds earlier than expected " |
| 407 | "(can be due to the CLOCK_REALTIME set to the past).", |
| 408 | next - now); |
| 409 | } |
| 410 | else if(unlikely(now - next > tick / 2)) { |
| 411 | errno_clear(); |
| 412 | nd_log_limit_static_global_var(erl, 10, 0); |
| 413 | nd_log_limit(&erl, NDLS_DAEMON, NDLP_NOTICE, |
| 414 | "heartbeat clock: woke up %"PRIu64" microseconds later than expected " |
| 415 | "(can be due to system load or the CLOCK_REALTIME set to the future).", |
| 416 | now - next); |
| 417 | } |
| 418 | |
| 419 | if(unlikely(!hb->realtime)) { |
| 420 | // the first time return zero |
| 421 | dt = 0; |
| 422 | } |
| 423 | |
| 424 | hb->realtime = now; |
| 425 | return dt; |
| 426 | } |
| 427 | |
| 428 | #if defined(OS_WINDOWS) |
| 429 | void sleep_usec_with_now(usec_t usec, usec_t started_ut __maybe_unused) { |
| 430 | if (usec == 0) |
| 431 | return; |
| 432 | |
| 433 | // Honor Windows timer granularity by rounding the requested duration |
| 434 | // up to the next multiple of the effective clock resolution. |
| 435 | usec_t res_ut = clock_realtime_resolution ? clock_realtime_resolution : USEC_PER_MS; |
| 436 | usec_t to_sleep_ut = usec; |
| 437 | if (res_ut) { |
| 438 | to_sleep_ut = ((to_sleep_ut + res_ut - 1) / res_ut) * res_ut; // round up |
| 439 | } |
| 440 | |
| 441 | // Convert microseconds to milliseconds for Sleep(), rounding up |
| 442 | DWORD sleep_ms = (DWORD)((to_sleep_ut + (USEC_PER_MS - 1)) / USEC_PER_MS); |
| 443 | if (sleep_ms == 0) |
| 444 | sleep_ms = 1; // safety: always sleep at least 1ms |
| 445 | |
| 446 | Sleep(sleep_ms); |
| 447 | } |
| 448 | #else |
| 449 | void sleep_usec_with_now(usec_t usec, usec_t started_ut) { |
| 450 | // we expect microseconds (1.000.000 per second) |
| 451 | // but timespec is nanoseconds (1.000.000.000 per second) |
| 452 | struct timespec rem = { 0, 0 }, req = { |
| 453 | .tv_sec = (time_t) (usec / USEC_PER_SEC), |
| 454 | .tv_nsec = (suseconds_t) ((usec % USEC_PER_SEC) * NSEC_PER_USEC) |
| 455 | }; |
| 456 | |
| 457 | // make sure errno is not EINTR |
| 458 | errno_clear(); |
| 459 | |
| 460 | if(!started_ut) |
| 461 | started_ut = now_realtime_usec(); |
| 462 | |
| 463 | usec_t end_ut = started_ut + usec; |
| 464 | |
| 465 | while (nanosleep(&req, &rem) != 0) { |
| 466 | if (likely(errno == EINTR && (rem.tv_sec || rem.tv_nsec))) { |
| 467 | req = rem; |
| 468 | rem = (struct timespec){ 0, 0 }; |
| 469 | |
| 470 | // break an infinite loop |
| 471 | errno_clear(); |
| 472 | |
| 473 | usec_t now_ut = now_realtime_usec(); |
| 474 | if(now_ut >= end_ut) |
| 475 | break; |
| 476 | |
| 477 | usec_t remaining_ut = (usec_t)req.tv_sec * USEC_PER_SEC + (usec_t)req.tv_nsec * NSEC_PER_USEC > usec; |
| 478 | usec_t check_ut = now_ut - started_ut; |
| 479 | if(remaining_ut > check_ut) { |
| 480 | req = (struct timespec){ |
| 481 | .tv_sec = (time_t) ( check_ut / USEC_PER_SEC), |
| 482 | .tv_nsec = (suseconds_t) ((check_ut % USEC_PER_SEC) * NSEC_PER_USEC) |
| 483 | }; |
| 484 | } |
| 485 | } |
| 486 | else { |
| 487 | netdata_log_error("Cannot nanosleep() for %"PRIu64" microseconds.", usec); |
| 488 | break; |
| 489 | } |
| 490 | } |
| 491 | } |
| 492 | #endif |
| 493 | |
| 494 | static inline collected_number uptime_from_boottime(void) { |
| 495 | #ifdef CLOCK_BOOTTIME_IS_AVAILABLE |
| 496 | return (collected_number)(now_boottime_usec() / USEC_PER_MS); |
| 497 | #else |
| 498 | netdata_log_error("uptime cannot be read from CLOCK_BOOTTIME on this system."); |
| 499 | return 0; |
| 500 | #endif |
| 501 | } |
| 502 | |
| 503 | static procfile *read_proc_uptime_ff = NULL; |
| 504 | static inline collected_number read_proc_uptime(const char *filename) { |
| 505 | if(unlikely(!read_proc_uptime_ff)) { |
| 506 | read_proc_uptime_ff = procfile_open(filename, " \t", PROCFILE_FLAG_DEFAULT); |
| 507 | if(unlikely(!read_proc_uptime_ff)) return 0; |
| 508 | } |
| 509 | |
| 510 | read_proc_uptime_ff = procfile_readall(read_proc_uptime_ff); |
| 511 | if(unlikely(!read_proc_uptime_ff)) return 0; |
| 512 | |
| 513 | if(unlikely(procfile_lines(read_proc_uptime_ff) < 1)) { |
| 514 | netdata_log_error("/proc/uptime has no lines."); |
| 515 | return 0; |
| 516 | } |
| 517 | if(unlikely(procfile_linewords(read_proc_uptime_ff, 0) < 1)) { |
| 518 | netdata_log_error("/proc/uptime has less than 1 word in it."); |
| 519 | return 0; |
| 520 | } |
| 521 | |
| 522 | return (collected_number)(strtondd(procfile_lineword(read_proc_uptime_ff, 0, 0), NULL) * 1000.0); |
| 523 | } |
| 524 | |
| 525 | inline collected_number uptime_msec(const char *filename){ |
| 526 | static int use_boottime = -1; |
| 527 | |
| 528 | if(unlikely(use_boottime == -1)) { |
| 529 | collected_number uptime_boottime = uptime_from_boottime(); |
| 530 | collected_number uptime_proc = read_proc_uptime(filename); |
| 531 | |
| 532 | long long delta = (long long)uptime_boottime - (long long)uptime_proc; |
| 533 | if(delta < 0) delta = -delta; |
| 534 | |
| 535 | if(delta <= 1000 && uptime_boottime != 0) { |
| 536 | procfile_close(read_proc_uptime_ff); |
| 537 | netdata_log_info("Using now_boottime_usec() for uptime (dt is %lld ms)", delta); |
| 538 | use_boottime = 1; |
| 539 | } |
| 540 | else if(uptime_proc != 0) { |
| 541 | netdata_log_info("Using /proc/uptime for uptime (dt is %lld ms)", delta); |
| 542 | use_boottime = 0; |
| 543 | } |
| 544 | else { |
| 545 | netdata_log_error("Cannot find any way to read uptime on this system."); |
| 546 | return 1; |
| 547 | } |
| 548 | } |
| 549 | |
| 550 | collected_number uptime; |
| 551 | if(use_boottime) |
| 552 | uptime = uptime_from_boottime(); |
| 553 | else |
| 554 | uptime = read_proc_uptime(filename); |
| 555 | |
| 556 | return uptime; |
| 557 | } |