gettime: improve gettimeofday() offload support
[fio.git] / gettime.c
index 1648b17b677f3325664282eb66052f40a2b646fd..e2746711d2e4e2b51b914a98a2c9d30e914beeda 100644 (file)
--- a/gettime.c
+++ b/gettime.c
 #include "hash.h"
 #include "os/os.h"
 
-#ifdef ARCH_HAVE_CPU_CLOCK
+#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;
-       unsigned long last_cycles;
+       int warned;
 };
+#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;
-enum fio_cs fio_clock_source_inited = CS_INVAL;
+static enum fio_cs fio_clock_source_inited = CS_INVAL;
 
 #ifdef FIO_DEBUG_TIME
 
@@ -121,40 +125,34 @@ static void fio_init gtod_init(void)
 
 #endif /* FIO_DEBUG_TIME */
 
+#ifdef CONFIG_CLOCK_GETTIME
 static int fill_clock_gettime(struct timespec *ts)
 {
-#ifdef FIO_HAVE_CLOCK_MONOTONIC
+#ifdef CONFIG_CLOCK_MONOTONIC
        return clock_gettime(CLOCK_MONOTONIC, ts);
 #else
        return clock_gettime(CLOCK_REALTIME, ts);
 #endif
 }
-
-#ifdef FIO_DEBUG_TIME
-void fio_gettime(struct timeval *tp, void *caller)
-#else
-void fio_gettime(struct timeval *tp, void fio_unused *caller)
 #endif
+
+static void __fio_gettime(struct timeval *tp)
 {
        struct tv_valid *tv;
 
-#ifdef FIO_DEBUG_TIME
-       if (!caller)
-               caller = __builtin_return_address(0);
-
-       gtod_log_caller(caller);
-#endif
-       if (fio_tv) {
-               memcpy(tp, fio_tv, sizeof(*tp));
-               return;
-       }
-
+#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;
 
@@ -167,18 +165,25 @@ 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 (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;
+               if (t < tv->last_cycles && tv->last_tv_valid &&
+                   !tv->warned) {
+                       log_err("fio: CPU clock going back in time\n");
+                       tv->warned = 1;
+               }
 
+               tv->last_cycles = t;
+               tv->last_tv_valid = 1;
+#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;
@@ -188,42 +193,45 @@ void fio_gettime(struct timeval *tp, void fio_unused *caller)
                log_err("fio: invalid clock source %d\n", fio_clock_source);
                break;
        }
+}
 
-       /*
-        * 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));
-       }
+#ifdef FIO_DEBUG_TIME
+void fio_gettime(struct timeval *tp, void *caller)
+#else
+void fio_gettime(struct timeval *tp, void fio_unused *caller)
+#endif
+{
+#ifdef FIO_DEBUG_TIME
+       if (!caller)
+               caller = __builtin_return_address(0);
+
+       gtod_log_caller(caller);
+#endif
+       if (fio_unlikely(fio_gettime_offload(tp)))
+               return;
+
+       __fio_gettime(tp);
 }
 
-#ifdef ARCH_HAVE_CPU_CLOCK
+#if defined(ARCH_HAVE_CPU_CLOCK) && !defined(ARCH_CPU_CLOCK_CYCLES_PER_USEC)
 static unsigned long get_cycles_per_usec(void)
 {
-       struct timespec ts;
        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;
 
-       fill_clock_gettime(&ts);
-       s.tv_sec = ts.tv_sec;
-       s.tv_usec = ts.tv_nsec / 1000;
+#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 {
-               unsigned long long elapsed;
+               uint64_t elapsed;
 
-               fill_clock_gettime(&ts);
-               e.tv_sec = ts.tv_sec;
-               e.tv_usec = ts.tv_nsec / 1000;
+               __fio_gettime(&e);
 
                elapsed = utime_since(&s, &e);
                if (elapsed >= 1280) {
@@ -232,15 +240,16 @@ 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();
@@ -254,6 +263,13 @@ 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;
@@ -270,47 +286,66 @@ 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 + 5) / 10;
-       dprint(FD_TIME, "avg: %lu\n", avg);
+       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)
 {
-}
+#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(sizeof(*t), 1);
-       if (pthread_setspecific(tv_tls_key, t))
+       t = calloc(1, sizeof(*t));
+       if (pthread_setspecific(tv_tls_key, t)) {
                log_err("fio: can't set TLS key\n");
+               assert(0);
+       }
 }
 
 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;
-       calibrate_cpu_clock();
+
+       if (calibrate_cpu_clock())
+               tsc_reliable = 0;
 
        /*
         * If the arch sets tsc_reliable != 0, then it must be good enough
@@ -324,7 +359,7 @@ void fio_clock_init(void)
                log_info("fio: clocksource=cpu may not be reliable\n");
 }
 
-uint64_t utime_since(struct timeval *s, struct timeval *e)
+uint64_t utime_since(const struct timeval *s, const struct timeval *e)
 {
        long sec, usec;
        uint64_t ret;
@@ -347,7 +382,7 @@ uint64_t utime_since(struct timeval *s, struct timeval *e)
        return ret;
 }
 
-uint64_t utime_since_now(struct timeval *s)
+uint64_t utime_since_now(const struct timeval *s)
 {
        struct timeval t;
 
@@ -355,7 +390,7 @@ uint64_t utime_since_now(struct timeval *s)
        return utime_since(s, &t);
 }
 
-uint64_t mtime_since(struct timeval *s, struct timeval *e)
+uint64_t mtime_since(const struct timeval *s, const struct timeval *e)
 {
        long sec, usec, ret;
 
@@ -376,7 +411,7 @@ uint64_t mtime_since(struct timeval *s, struct timeval *e)
        return ret;
 }
 
-uint64_t mtime_since_now(struct timeval *s)
+uint64_t mtime_since_now(const struct timeval *s)
 {
        struct timeval t;
        void *p = __builtin_return_address(0);
@@ -385,19 +420,20 @@ uint64_t mtime_since_now(struct timeval *s)
        return mtime_since(s, &t);
 }
 
-uint64_t time_since_now(struct timeval *s)
+uint64_t time_since_now(const struct timeval *s)
 {
        return mtime_since_now(s) / 1000;
 }
 
-#if defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK)
+#if defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK)  && \
+    defined(CONFIG_SFAA)
 
 #define CLOCK_ENTRIES  100000
 
 struct clock_entry {
-       unsigned long seq;
-       unsigned long tsc;
-       unsigned long cpu;
+       uint32_t seq;
+       uint32_t cpu;
+       uint64_t tsc;
 };
 
 struct clock_thread {
@@ -405,11 +441,11 @@ struct clock_thread {
        int cpu;
        pthread_mutex_t lock;
        pthread_mutex_t started;
-       uint64_t *seq;
+       uint32_t *seq;
        struct clock_entry *entries;
 };
 
-static inline uint64_t atomic64_inc_return(uint64_t *seq)
+static inline uint32_t atomic32_inc_return(uint32_t *seq)
 {
        return 1 + __sync_fetch_and_add(seq, 1);
 }
@@ -419,6 +455,7 @@ 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));
@@ -432,13 +469,17 @@ static void *clock_thread_fn(void *data)
        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++) {
-               uint64_t seq, tsc;
+               uint32_t seq;
+               uint64_t tsc;
 
                c->cpu = t->cpu;
                do {
-                       seq = atomic64_inc_return(t->seq);
+                       seq = atomic32_inc_return(t->seq);
+                       if (seq < last_seq)
+                               break;
                        tsc = get_cpu_clock();
                } while (seq != *t->seq);
 
@@ -446,7 +487,16 @@ static void *clock_thread_fn(void *data)
                c->tsc = tsc;
        }
 
-       log_info("cs: cpu%3d: %lu clocks seen\n", t->cpu, t->entries[CLOCK_ENTRIES - 1].tsc - t->entries[0].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;
 }
 
@@ -463,25 +513,32 @@ static int clock_cmp(const void *p1, const void *p2)
 
 int fio_monotonic_clocktest(void)
 {
-       struct clock_thread *threads;
+       struct clock_thread *cthreads;
        unsigned int nr_cpus = cpus_online();
        struct clock_entry *entries;
-       unsigned long tentries, failed;
-       uint64_t seq = 0;
-       int i;
+       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");
 
+#ifdef FIO_INC_DEBUG
        fio_debug |= 1U << FD_TIME;
+#endif
        calibrate_cpu_clock();
+#ifdef FIO_INC_DEBUG
        fio_debug &= ~(1U << FD_TIME);
+#endif
 
-       threads = malloc(nr_cpus * sizeof(struct clock_thread));
+       cthreads = 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];
+               struct clock_thread *t = &cthreads[i];
 
                t->cpu = i;
                t->seq = &seq;
@@ -489,40 +546,44 @@ int fio_monotonic_clocktest(void)
                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);
+               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];
+               struct clock_thread *t = &cthreads[i];
 
                pthread_mutex_lock(&t->started);
        }
 
        for (i = 0; i < nr_cpus; i++) {
-               struct clock_thread *t = &threads[i];
+               struct clock_thread *t = &cthreads[i];
 
                pthread_mutex_unlock(&t->lock);
        }
 
-       for (failed = i = 0; i < nr_cpus; i++) {
-               struct clock_thread *t = &threads[i];
+       for (i = 0; i < nr_cpus; i++) {
+               struct clock_thread *t = &cthreads[i];
                void *ret;
 
                pthread_join(t->thread, &ret);
                if (ret)
                        failed++;
        }
-       free(threads);
+       free(cthreads);
 
        if (failed) {
-               log_err("Clocksource test: %u threads failed\n", 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++) {
-               struct clock_entry *prev, *this = &entries[i];
+               this = &entries[i];
 
                if (!i) {
                        prev = this;
@@ -532,9 +593,10 @@ int fio_monotonic_clocktest(void)
                if (prev->tsc > this->tsc) {
                        uint64_t diff = prev->tsc - this->tsc;
 
-                       log_info("cs: CPU clock mismatch (diff=%lu):\n", diff);
-                       log_info("\t CPU%3lu: TSC=%lu, SEQ=%lu\n", prev->cpu, prev->tsc, prev->seq);
-                       log_info("\t CPU%3lu: TSC=%lu, SEQ=%lu\n", this->cpu, this->tsc, this->seq);
+                       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++;
                }