X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=gettime.c;h=8991703fd0662fad4616ed8ab66f154f12c0ade9;hp=9f23e3fff526e0611df0dd1c9d6dc1b62d059916;hb=2f5a39d5a00ab8dca888360c63b64623c710b9ab;hpb=42634d2118b41f26151f5b708e83d40061570653 diff --git a/gettime.c b/gettime.c index 9f23e3ff..8991703f 100644 --- a/gettime.c +++ b/gettime.c @@ -11,14 +11,24 @@ #include "smalloc.h" #include "hash.h" +#include "os/os.h" #ifdef ARCH_HAVE_CPU_CLOCK static unsigned long cycles_per_usec; -static unsigned long last_cycles; +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 -static struct timeval last_tv; -static int last_tv_valid; enum fio_cs fio_clock_source = FIO_PREFERRED_CLOCK_SOURCE; int fio_clock_source_set = 0; @@ -115,35 +125,38 @@ static void fio_init gtod_init(void) #endif /* FIO_DEBUG_TIME */ -#ifdef FIO_DEBUG_TIME -void fio_gettime(struct timeval *tp, void *caller) +#ifdef CONFIG_CLOCK_GETTIME +static int fill_clock_gettime(struct timespec *ts) +{ +#ifdef CONFIG_CLOCK_MONOTONIC + return clock_gettime(CLOCK_MONOTONIC, ts); #else -void fio_gettime(struct timeval *tp, void fio_unused *caller) + return clock_gettime(CLOCK_REALTIME, ts); +#endif +} #endif + +static void *__fio_gettime(struct timeval *tp) { -#ifdef FIO_DEBUG_TIME - if (!caller) - caller = __builtin_return_address(0); + struct tv_valid *tv; - gtod_log_caller(caller); +#ifdef CONFIG_TLS_THREAD + tv = &static_tv_valid; +#else + tv = pthread_getspecific(tv_tls_key); #endif - if (fio_tv) { - memcpy(tp, fio_tv, sizeof(*tp)); - return; - } 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; -#ifdef FIO_HAVE_CLOCK_MONOTONIC - if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0) { -#else - if (clock_gettime(CLOCK_REALTIME, &ts) < 0) { -#endif + if (fill_clock_gettime(&ts) < 0) { log_err("fio: clock_gettime fails\n"); assert(0); } @@ -152,20 +165,21 @@ void fio_gettime(struct timeval *tp, void fio_unused *caller) tp->tv_usec = ts.tv_nsec / 1000; break; } +#endif #ifdef ARCH_HAVE_CPU_CLOCK case CS_CPUCLOCK: { - unsigned long long usecs, t; + uint64_t usecs, t; t = get_cpu_clock(); - if (t < last_cycles) { + if (tv && t < tv->last_cycles) { dprint(FD_TIME, "CPU clock going back in time\n"); - t = last_cycles; - } + t = tv->last_cycles; + } else if (tv) + tv->last_cycles = t; - usecs = t / cycles_per_usec; + usecs = (t * inv_cycles_per_usec) / 16777216UL; tp->tv_sec = usecs / 1000000; tp->tv_usec = usecs % 1000000; - last_cycles = t; break; } #endif @@ -174,33 +188,67 @@ void fio_gettime(struct timeval *tp, void fio_unused *caller) 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 (last_tv_valid) { - if (tp->tv_sec < last_tv.tv_sec) - tp->tv_sec = last_tv.tv_sec; - else if (last_tv.tv_sec == tp->tv_sec && - tp->tv_usec < last_tv.tv_usec) - tp->tv_usec = last_tv.tv_usec; + 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)); } - last_tv_valid = 1; - memcpy(&last_tv, tp, sizeof(*tp)); } #ifdef ARCH_HAVE_CPU_CLOCK static unsigned long get_cycles_per_usec(void) { struct timeval s, e; - unsigned long long c_s, c_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); - gettimeofday(&s, NULL); c_s = get_cpu_clock(); do { - unsigned long long elapsed; + uint64_t elapsed; + + __fio_gettime(&e); - gettimeofday(&e, NULL); elapsed = utime_since(&s, &e); if (elapsed >= 1280) { c_e = get_cpu_clock(); @@ -208,15 +256,16 @@ static unsigned long get_cycles_per_usec(void) } } while (1); + fio_clock_source = old_cs; return (c_e - c_s + 127) >> 7; } #define NR_TIME_ITERS 50 -static void calibrate_cpu_clock(void) +static int calibrate_cpu_clock(void) { double delta, mean, S; - unsigned long avg, cycles[NR_TIME_ITERS]; + uint64_t avg, cycles[NR_TIME_ITERS]; int i, samples; cycles[0] = get_cycles_per_usec(); @@ -230,6 +279,13 @@ static void calibrate_cpu_clock(void) } } + /* + * 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; @@ -246,17 +302,42 @@ static void calibrate_cpu_clock(void) mean /= 10.0; for (i = 0; i < NR_TIME_ITERS; i++) - dprint(FD_TIME, "cycles[%d]=%lu\n", i, cycles[i] / 10); + dprint(FD_TIME, "cycles[%d]=%llu\n", i, + (unsigned long long) cycles[i] / 10); avg /= samples; - avg = (avg + 9) / 10; - dprint(FD_TIME, "avg: %lu\n", avg); + 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 void calibrate_cpu_clock(void) +static int calibrate_cpu_clock(void) +{ + return 1; +} +#endif + +#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 @@ -266,9 +347,15 @@ void fio_clock_init(void) if (fio_clock_source == fio_clock_source_inited) return; - last_tv_valid = 0; +#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; - calibrate_cpu_clock(); + + if (calibrate_cpu_clock()) + tsc_reliable = 0; /* * If the arch sets tsc_reliable != 0, then it must be good enough @@ -282,10 +369,10 @@ void fio_clock_init(void) log_info("fio: clocksource=cpu may not be reliable\n"); } -unsigned long long utime_since(struct timeval *s, struct timeval *e) +uint64_t utime_since(struct timeval *s, struct timeval *e) { long sec, usec; - unsigned long long ret; + uint64_t ret; sec = e->tv_sec - s->tv_sec; usec = e->tv_usec - s->tv_usec; @@ -305,7 +392,7 @@ unsigned long long utime_since(struct timeval *s, struct timeval *e) return ret; } -unsigned long long utime_since_now(struct timeval *s) +uint64_t utime_since_now(struct timeval *s) { struct timeval t; @@ -313,7 +400,7 @@ unsigned long long utime_since_now(struct timeval *s) return utime_since(s, &t); } -unsigned long mtime_since(struct timeval *s, struct timeval *e) +uint64_t mtime_since(struct timeval *s, struct timeval *e) { long sec, usec, ret; @@ -334,7 +421,7 @@ unsigned long mtime_since(struct timeval *s, struct timeval *e) return ret; } -unsigned long mtime_since_now(struct timeval *s) +uint64_t mtime_since_now(struct timeval *s) { struct timeval t; void *p = __builtin_return_address(0); @@ -343,7 +430,197 @@ unsigned long mtime_since_now(struct timeval *s) return mtime_since(s, &t); } -unsigned long time_since_now(struct timeval *s) +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; + struct clock_entry *prev, *this; + uint32_t seq = 0; + 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); + pthread_create(&t->thread, NULL, clock_thread_fn, t); + } + + 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 (failed = 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