| /* |
| * Clock functions |
| */ |
| |
| #include <unistd.h> |
| #include <math.h> |
| #include <sys/time.h> |
| #include <time.h> |
| |
| #include "fio.h" |
| #include "smalloc.h" |
| |
| #include "hash.h" |
| #include "os/os.h" |
| |
| #if defined(ARCH_HAVE_CPU_CLOCK) && !defined(ARCH_CPU_CLOCK_CYCLES_PER_USEC) |
| static unsigned long cycles_per_usec; |
| static unsigned long inv_cycles_per_usec; |
| #endif |
| int tsc_reliable = 0; |
| |
| struct tv_valid { |
| struct timeval last_tv; |
| uint64_t last_cycles; |
| int last_tv_valid; |
| }; |
| #ifdef CONFIG_TLS_THREAD |
| static __thread struct tv_valid static_tv_valid; |
| #else |
| static pthread_key_t tv_tls_key; |
| #endif |
| |
| enum fio_cs fio_clock_source = FIO_PREFERRED_CLOCK_SOURCE; |
| int fio_clock_source_set = 0; |
| static enum fio_cs fio_clock_source_inited = CS_INVAL; |
| |
| #ifdef FIO_DEBUG_TIME |
| |
| #define HASH_BITS 8 |
| #define HASH_SIZE (1 << HASH_BITS) |
| |
| static struct flist_head hash[HASH_SIZE]; |
| static int gtod_inited; |
| |
| struct gtod_log { |
| struct flist_head list; |
| void *caller; |
| unsigned long calls; |
| }; |
| |
| static struct gtod_log *find_hash(void *caller) |
| { |
| unsigned long h = hash_ptr(caller, HASH_BITS); |
| struct flist_head *entry; |
| |
| flist_for_each(entry, &hash[h]) { |
| struct gtod_log *log = flist_entry(entry, struct gtod_log, |
| list); |
| |
| if (log->caller == caller) |
| return log; |
| } |
| |
| return NULL; |
| } |
| |
| static struct gtod_log *find_log(void *caller) |
| { |
| struct gtod_log *log = find_hash(caller); |
| |
| if (!log) { |
| unsigned long h; |
| |
| log = malloc(sizeof(*log)); |
| INIT_FLIST_HEAD(&log->list); |
| log->caller = caller; |
| log->calls = 0; |
| |
| h = hash_ptr(caller, HASH_BITS); |
| flist_add_tail(&log->list, &hash[h]); |
| } |
| |
| return log; |
| } |
| |
| static void gtod_log_caller(void *caller) |
| { |
| if (gtod_inited) { |
| struct gtod_log *log = find_log(caller); |
| |
| log->calls++; |
| } |
| } |
| |
| static void fio_exit fio_dump_gtod(void) |
| { |
| unsigned long total_calls = 0; |
| int i; |
| |
| for (i = 0; i < HASH_SIZE; i++) { |
| struct flist_head *entry; |
| struct gtod_log *log; |
| |
| flist_for_each(entry, &hash[i]) { |
| log = flist_entry(entry, struct gtod_log, list); |
| |
| printf("function %p, calls %lu\n", log->caller, |
| log->calls); |
| total_calls += log->calls; |
| } |
| } |
| |
| printf("Total %lu gettimeofday\n", total_calls); |
| } |
| |
| static void fio_init gtod_init(void) |
| { |
| int i; |
| |
| for (i = 0; i < HASH_SIZE; i++) |
| INIT_FLIST_HEAD(&hash[i]); |
| |
| gtod_inited = 1; |
| } |
| |
| #endif /* FIO_DEBUG_TIME */ |
| |
| #ifdef CONFIG_CLOCK_GETTIME |
| static int fill_clock_gettime(struct timespec *ts) |
| { |
| #ifdef CONFIG_CLOCK_MONOTONIC |
| return clock_gettime(CLOCK_MONOTONIC, ts); |
| #else |
| return clock_gettime(CLOCK_REALTIME, ts); |
| #endif |
| } |
| #endif |
| |
| static void *__fio_gettime(struct timeval *tp) |
| { |
| struct tv_valid *tv; |
| |
| #ifdef CONFIG_TLS_THREAD |
| tv = &static_tv_valid; |
| #else |
| tv = pthread_getspecific(tv_tls_key); |
| #endif |
| |
| switch (fio_clock_source) { |
| #ifdef CONFIG_GETTIMEOFDAY |
| case CS_GTOD: |
| gettimeofday(tp, NULL); |
| break; |
| #endif |
| #ifdef CONFIG_CLOCK_GETTIME |
| case CS_CGETTIME: { |
| struct timespec ts; |
| |
| if (fill_clock_gettime(&ts) < 0) { |
| log_err("fio: clock_gettime fails\n"); |
| assert(0); |
| } |
| |
| tp->tv_sec = ts.tv_sec; |
| tp->tv_usec = ts.tv_nsec / 1000; |
| break; |
| } |
| #endif |
| #ifdef ARCH_HAVE_CPU_CLOCK |
| case CS_CPUCLOCK: { |
| uint64_t usecs, t; |
| |
| t = get_cpu_clock(); |
| if (tv && t < tv->last_cycles) { |
| dprint(FD_TIME, "CPU clock going back in time\n"); |
| t = tv->last_cycles; |
| } else if (tv) |
| tv->last_cycles = t; |
| |
| #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC |
| usecs = t / ARCH_CPU_CLOCK_CYCLES_PER_USEC; |
| #else |
| usecs = (t * inv_cycles_per_usec) / 16777216UL; |
| #endif |
| tp->tv_sec = usecs / 1000000; |
| tp->tv_usec = usecs % 1000000; |
| break; |
| } |
| #endif |
| default: |
| log_err("fio: invalid clock source %d\n", fio_clock_source); |
| break; |
| } |
| |
| return tv; |
| } |
| |
| #ifdef FIO_DEBUG_TIME |
| void fio_gettime(struct timeval *tp, void *caller) |
| #else |
| void fio_gettime(struct timeval *tp, void fio_unused *caller) |
| #endif |
| { |
| struct tv_valid *tv; |
| |
| #ifdef FIO_DEBUG_TIME |
| if (!caller) |
| caller = __builtin_return_address(0); |
| |
| gtod_log_caller(caller); |
| #endif |
| if (fio_unlikely(fio_tv)) { |
| memcpy(tp, fio_tv, sizeof(*tp)); |
| return; |
| } |
| |
| tv = __fio_gettime(tp); |
| |
| /* |
| * If Linux is using the tsc clock on non-synced processors, |
| * sometimes time can appear to drift backwards. Fix that up. |
| */ |
| if (tv) { |
| if (tv->last_tv_valid) { |
| if (tp->tv_sec < tv->last_tv.tv_sec) |
| tp->tv_sec = tv->last_tv.tv_sec; |
| else if (tv->last_tv.tv_sec == tp->tv_sec && |
| tp->tv_usec < tv->last_tv.tv_usec) |
| tp->tv_usec = tv->last_tv.tv_usec; |
| } |
| tv->last_tv_valid = 1; |
| memcpy(&tv->last_tv, tp, sizeof(*tp)); |
| } |
| } |
| |
| #if defined(ARCH_HAVE_CPU_CLOCK) && !defined(ARCH_CPU_CLOCK_CYCLES_PER_USEC) |
| static unsigned long get_cycles_per_usec(void) |
| { |
| struct timeval s, e; |
| uint64_t c_s, c_e; |
| enum fio_cs old_cs = fio_clock_source; |
| |
| #ifdef CONFIG_CLOCK_GETTIME |
| fio_clock_source = CS_CGETTIME; |
| #else |
| fio_clock_source = CS_GTOD; |
| #endif |
| __fio_gettime(&s); |
| |
| c_s = get_cpu_clock(); |
| do { |
| uint64_t elapsed; |
| |
| __fio_gettime(&e); |
| |
| elapsed = utime_since(&s, &e); |
| if (elapsed >= 1280) { |
| c_e = get_cpu_clock(); |
| break; |
| } |
| } while (1); |
| |
| fio_clock_source = old_cs; |
| return (c_e - c_s + 127) >> 7; |
| } |
| |
| #define NR_TIME_ITERS 50 |
| |
| static int calibrate_cpu_clock(void) |
| { |
| double delta, mean, S; |
| uint64_t avg, cycles[NR_TIME_ITERS]; |
| int i, samples; |
| |
| cycles[0] = get_cycles_per_usec(); |
| S = delta = mean = 0.0; |
| for (i = 0; i < NR_TIME_ITERS; i++) { |
| cycles[i] = get_cycles_per_usec(); |
| delta = cycles[i] - mean; |
| if (delta) { |
| mean += delta / (i + 1.0); |
| S += delta * (cycles[i] - mean); |
| } |
| } |
| |
| /* |
| * The most common platform clock breakage is returning zero |
| * indefinitely. Check for that and return failure. |
| */ |
| if (!cycles[0] && !cycles[NR_TIME_ITERS - 1]) |
| return 1; |
| |
| S = sqrt(S / (NR_TIME_ITERS - 1.0)); |
| |
| samples = avg = 0; |
| for (i = 0; i < NR_TIME_ITERS; i++) { |
| double this = cycles[i]; |
| |
| if ((fmax(this, mean) - fmin(this, mean)) > S) |
| continue; |
| samples++; |
| avg += this; |
| } |
| |
| S /= (double) NR_TIME_ITERS; |
| mean /= 10.0; |
| |
| for (i = 0; i < NR_TIME_ITERS; i++) |
| dprint(FD_TIME, "cycles[%d]=%llu\n", i, |
| (unsigned long long) cycles[i] / 10); |
| |
| avg /= samples; |
| avg = (avg + 5) / 10; |
| dprint(FD_TIME, "avg: %llu\n", (unsigned long long) avg); |
| dprint(FD_TIME, "mean=%f, S=%f\n", mean, S); |
| |
| cycles_per_usec = avg; |
| inv_cycles_per_usec = 16777216UL / cycles_per_usec; |
| dprint(FD_TIME, "inv_cycles_per_usec=%lu\n", inv_cycles_per_usec); |
| return 0; |
| } |
| #else |
| static int calibrate_cpu_clock(void) |
| { |
| #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC |
| return 0; |
| #else |
| return 1; |
| #endif |
| } |
| #endif // ARCH_HAVE_CPU_CLOCK |
| |
| #ifndef CONFIG_TLS_THREAD |
| void fio_local_clock_init(int is_thread) |
| { |
| struct tv_valid *t; |
| |
| t = calloc(1, sizeof(*t)); |
| if (pthread_setspecific(tv_tls_key, t)) |
| log_err("fio: can't set TLS key\n"); |
| } |
| |
| static void kill_tv_tls_key(void *data) |
| { |
| free(data); |
| } |
| #else |
| void fio_local_clock_init(int is_thread) |
| { |
| } |
| #endif |
| |
| void fio_clock_init(void) |
| { |
| if (fio_clock_source == fio_clock_source_inited) |
| return; |
| |
| #ifndef CONFIG_TLS_THREAD |
| if (pthread_key_create(&tv_tls_key, kill_tv_tls_key)) |
| log_err("fio: can't create TLS key\n"); |
| #endif |
| |
| fio_clock_source_inited = fio_clock_source; |
| |
| if (calibrate_cpu_clock()) |
| tsc_reliable = 0; |
| |
| /* |
| * If the arch sets tsc_reliable != 0, then it must be good enough |
| * to use as THE clock source. For x86 CPUs, this means the TSC |
| * runs at a constant rate and is synced across CPU cores. |
| */ |
| if (tsc_reliable) { |
| if (!fio_clock_source_set) |
| fio_clock_source = CS_CPUCLOCK; |
| } else if (fio_clock_source == CS_CPUCLOCK) |
| log_info("fio: clocksource=cpu may not be reliable\n"); |
| } |
| |
| uint64_t utime_since(struct timeval *s, struct timeval *e) |
| { |
| long sec, usec; |
| uint64_t ret; |
| |
| sec = e->tv_sec - s->tv_sec; |
| usec = e->tv_usec - s->tv_usec; |
| if (sec > 0 && usec < 0) { |
| sec--; |
| usec += 1000000; |
| } |
| |
| /* |
| * time warp bug on some kernels? |
| */ |
| if (sec < 0 || (sec == 0 && usec < 0)) |
| return 0; |
| |
| ret = sec * 1000000ULL + usec; |
| |
| return ret; |
| } |
| |
| uint64_t utime_since_now(struct timeval *s) |
| { |
| struct timeval t; |
| |
| fio_gettime(&t, NULL); |
| return utime_since(s, &t); |
| } |
| |
| uint64_t mtime_since(struct timeval *s, struct timeval *e) |
| { |
| long sec, usec, ret; |
| |
| sec = e->tv_sec - s->tv_sec; |
| usec = e->tv_usec - s->tv_usec; |
| if (sec > 0 && usec < 0) { |
| sec--; |
| usec += 1000000; |
| } |
| |
| if (sec < 0 || (sec == 0 && usec < 0)) |
| return 0; |
| |
| sec *= 1000UL; |
| usec /= 1000UL; |
| ret = sec + usec; |
| |
| return ret; |
| } |
| |
| uint64_t mtime_since_now(struct timeval *s) |
| { |
| struct timeval t; |
| void *p = __builtin_return_address(0); |
| |
| fio_gettime(&t, p); |
| return mtime_since(s, &t); |
| } |
| |
| uint64_t time_since_now(struct timeval *s) |
| { |
| return mtime_since_now(s) / 1000; |
| } |
| |
| #if defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK) && \ |
| defined(CONFIG_SFAA) |
| |
| #define CLOCK_ENTRIES 100000 |
| |
| struct clock_entry { |
| uint32_t seq; |
| uint32_t cpu; |
| uint64_t tsc; |
| }; |
| |
| struct clock_thread { |
| pthread_t thread; |
| int cpu; |
| pthread_mutex_t lock; |
| pthread_mutex_t started; |
| uint32_t *seq; |
| struct clock_entry *entries; |
| }; |
| |
| static inline uint32_t atomic32_inc_return(uint32_t *seq) |
| { |
| return 1 + __sync_fetch_and_add(seq, 1); |
| } |
| |
| static void *clock_thread_fn(void *data) |
| { |
| struct clock_thread *t = data; |
| struct clock_entry *c; |
| os_cpu_mask_t cpu_mask; |
| uint32_t last_seq; |
| int i; |
| |
| memset(&cpu_mask, 0, sizeof(cpu_mask)); |
| fio_cpu_set(&cpu_mask, t->cpu); |
| |
| if (fio_setaffinity(gettid(), cpu_mask) == -1) { |
| log_err("clock setaffinity failed\n"); |
| return (void *) 1; |
| } |
| |
| pthread_mutex_lock(&t->lock); |
| pthread_mutex_unlock(&t->started); |
| |
| last_seq = 0; |
| c = &t->entries[0]; |
| for (i = 0; i < CLOCK_ENTRIES; i++, c++) { |
| uint32_t seq; |
| uint64_t tsc; |
| |
| c->cpu = t->cpu; |
| do { |
| seq = atomic32_inc_return(t->seq); |
| if (seq < last_seq) |
| break; |
| tsc = get_cpu_clock(); |
| } while (seq != *t->seq); |
| |
| c->seq = seq; |
| c->tsc = tsc; |
| } |
| |
| log_info("cs: cpu%3d: %llu clocks seen\n", t->cpu, |
| (unsigned long long) t->entries[i - 1].tsc - t->entries[0].tsc); |
| |
| /* |
| * The most common platform clock breakage is returning zero |
| * indefinitely. Check for that and return failure. |
| */ |
| if (!t->entries[i - 1].tsc && !t->entries[0].tsc) |
| return (void *) 1; |
| |
| return NULL; |
| } |
| |
| static int clock_cmp(const void *p1, const void *p2) |
| { |
| const struct clock_entry *c1 = p1; |
| const struct clock_entry *c2 = p2; |
| |
| if (c1->seq == c2->seq) |
| log_err("cs: bug in atomic sequence!\n"); |
| |
| return c1->seq - c2->seq; |
| } |
| |
| int fio_monotonic_clocktest(void) |
| { |
| struct clock_thread *threads; |
| unsigned int nr_cpus = cpus_online(); |
| struct clock_entry *entries; |
| unsigned long tentries, failed = 0; |
| struct clock_entry *prev, *this; |
| uint32_t seq = 0; |
| unsigned int i; |
| |
| log_info("cs: reliable_tsc: %s\n", tsc_reliable ? "yes" : "no"); |
| |
| fio_debug |= 1U << FD_TIME; |
| calibrate_cpu_clock(); |
| fio_debug &= ~(1U << FD_TIME); |
| |
| threads = malloc(nr_cpus * sizeof(struct clock_thread)); |
| tentries = CLOCK_ENTRIES * nr_cpus; |
| entries = malloc(tentries * sizeof(struct clock_entry)); |
| |
| log_info("cs: Testing %u CPUs\n", nr_cpus); |
| |
| for (i = 0; i < nr_cpus; i++) { |
| struct clock_thread *t = &threads[i]; |
| |
| t->cpu = i; |
| t->seq = &seq; |
| t->entries = &entries[i * CLOCK_ENTRIES]; |
| pthread_mutex_init(&t->lock, NULL); |
| pthread_mutex_init(&t->started, NULL); |
| pthread_mutex_lock(&t->lock); |
| if (pthread_create(&t->thread, NULL, clock_thread_fn, t)) { |
| failed++; |
| nr_cpus = i; |
| break; |
| } |
| } |
| |
| for (i = 0; i < nr_cpus; i++) { |
| struct clock_thread *t = &threads[i]; |
| |
| pthread_mutex_lock(&t->started); |
| } |
| |
| for (i = 0; i < nr_cpus; i++) { |
| struct clock_thread *t = &threads[i]; |
| |
| pthread_mutex_unlock(&t->lock); |
| } |
| |
| for (i = 0; i < nr_cpus; i++) { |
| struct clock_thread *t = &threads[i]; |
| void *ret; |
| |
| pthread_join(t->thread, &ret); |
| if (ret) |
| failed++; |
| } |
| free(threads); |
| |
| if (failed) { |
| log_err("Clocksource test: %lu threads failed\n", failed); |
| goto err; |
| } |
| |
| qsort(entries, tentries, sizeof(struct clock_entry), clock_cmp); |
| |
| for (failed = i = 0; i < tentries; i++) { |
| this = &entries[i]; |
| |
| if (!i) { |
| prev = this; |
| continue; |
| } |
| |
| if (prev->tsc > this->tsc) { |
| uint64_t diff = prev->tsc - this->tsc; |
| |
| log_info("cs: CPU clock mismatch (diff=%llu):\n", |
| (unsigned long long) diff); |
| log_info("\t CPU%3u: TSC=%llu, SEQ=%u\n", prev->cpu, (unsigned long long) prev->tsc, prev->seq); |
| log_info("\t CPU%3u: TSC=%llu, SEQ=%u\n", this->cpu, (unsigned long long) this->tsc, this->seq); |
| failed++; |
| } |
| |
| prev = this; |
| } |
| |
| if (failed) |
| log_info("cs: Failed: %lu\n", failed); |
| else |
| log_info("cs: Pass!\n"); |
| |
| err: |
| free(entries); |
| return !!failed; |
| } |
| |
| #else /* defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK) */ |
| |
| int fio_monotonic_clocktest(void) |
| { |
| log_info("cs: current platform does not support CPU clocks\n"); |
| return 0; |
| } |
| |
| #endif |