Fix overflow caused by signed long division by unsigned long.

[fio.git] / gettime.c

diff --git a/gettime.c b/gettime.c
index f40abc7a5ad347a00a57092375c3b728ae1fbd16..964a52fa237afe50a05cd7d9081c3e29c26c70fc 100644 (file)
--- a/gettime.c
+++ b/gettime.c
@@ -13,12 +13,16 @@
 #include "hash.h"
 #include "os/os.h"
 
-#if defined(ARCH_HAVE_CPU_CLOCK) && !defined(ARCH_CPU_CLOCK_CYCLES_PER_USEC)
+#if defined(ARCH_HAVE_CPU_CLOCK)
+#ifndef ARCH_CPU_CLOCK_CYCLES_PER_USEC
 static unsigned long cycles_per_usec;
 static unsigned long inv_cycles_per_usec;
 static uint64_t max_cycles_for_mult;
+#endif
+#ifdef ARCH_CPU_CLOCK_WRAPS
 static unsigned long long cycles_start, cycles_wrap;
 #endif
+#endif
 int tsc_reliable = 0;
 
 struct tv_valid {
@@ -129,7 +133,9 @@ static void fio_init gtod_init(void)
 #ifdef CONFIG_CLOCK_GETTIME
 static int fill_clock_gettime(struct timespec *ts)
 {
-#ifdef CONFIG_CLOCK_MONOTONIC
+#if defined(CONFIG_CLOCK_MONOTONIC_RAW)
+       return clock_gettime(CLOCK_MONOTONIC_RAW, ts);
+#elif defined(CONFIG_CLOCK_MONOTONIC)
        return clock_gettime(CLOCK_MONOTONIC, ts);
 #else
        return clock_gettime(CLOCK_REALTIME, ts);
@@ -171,6 +177,7 @@ static void __fio_gettime(struct timeval *tp)
 #endif
 
                t = get_cpu_clock();
+#ifdef ARCH_CPU_CLOCK_WRAPS
                if (t < cycles_start && !cycles_wrap)
                        cycles_wrap = 1;
                else if (cycles_wrap && t >= cycles_start && !tv->warned) {
@@ -179,6 +186,7 @@ static void __fio_gettime(struct timeval *tp)
                }
 
                t -= cycles_start;
+#endif
                tv->last_cycles = t;
                tv->last_tv_valid = 1;
 #ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC
@@ -224,6 +232,7 @@ 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;
+       uint64_t elapsed;
 
 #ifdef CONFIG_CLOCK_GETTIME
        fio_clock_source = CS_CGETTIME;
@@ -234,8 +243,6 @@ static unsigned long get_cycles_per_usec(void)
 
        c_s = get_cpu_clock();
        do {
-               uint64_t elapsed;
-
                __fio_gettime(&e);
 
                elapsed = utime_since(&s, &e);
@@ -246,7 +253,7 @@ static unsigned long get_cycles_per_usec(void)
        } while (1);
 
        fio_clock_source = old_cs;
-       return (c_e - c_s + 127) >> 7;
+       return (c_e - c_s) / elapsed;
 }
 
 #define NR_TIME_ITERS  50
@@ -292,16 +299,11 @@ static int calibrate_cpu_clock(void)
        }
 
        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);
+               dprint(FD_TIME, "cycles[%d]=%llu\n", i, (unsigned long long) cycles[i]);
 
        avg /= samples;
-       avg = (avg + 5) / 10;
-       minc /= 10;
-       maxc /= 10;
        dprint(FD_TIME, "avg: %llu\n", (unsigned long long) avg);
        dprint(FD_TIME, "min=%llu, max=%llu, mean=%f, S=%f\n",
                        (unsigned long long) minc,
@@ -311,8 +313,10 @@ static int calibrate_cpu_clock(void)
        inv_cycles_per_usec = 16777216UL / cycles_per_usec;
        max_cycles_for_mult = ~0ULL / inv_cycles_per_usec;
        dprint(FD_TIME, "inv_cycles_per_usec=%lu\n", inv_cycles_per_usec);
+#ifdef ARCH_CPU_CLOCK_WRAPS
        cycles_start = get_cpu_clock();
        dprint(FD_TIME, "cycles_start=%llu\n", cycles_start);
+#endif
        return 0;
 }
 #else
@@ -420,8 +424,8 @@ uint64_t mtime_since(const struct timeval *s, const struct timeval *e)
        if (sec < 0 || (sec == 0 && usec < 0))
                return 0;
 
-       sec *= 1000UL;
-       usec /= 1000UL;
+       sec *= 1000;
+       usec /= 1000;
        ret = sec + usec;
 
        return ret;
@@ -475,21 +479,29 @@ static void *clock_thread_fn(void *data)
        struct clock_entry *c;
        os_cpu_mask_t cpu_mask;
        uint32_t last_seq;
+       unsigned long long first;
        int i;
 
-       memset(&cpu_mask, 0, sizeof(cpu_mask));
+       if (fio_cpuset_init(&cpu_mask)) {
+               int __err = errno;
+
+               log_err("clock cpuset init failed: %s\n", strerror(__err));
+               goto err_out;
+       }
+
        fio_cpu_set(&cpu_mask, t->cpu);
 
        if (fio_setaffinity(gettid(), cpu_mask) == -1) {
                int __err = errno;
 
                log_err("clock setaffinity failed: %s\n", strerror(__err));
-               return (void *) 1;
+               goto err;
        }
 
        pthread_mutex_lock(&t->lock);
        pthread_mutex_unlock(&t->started);
 
+       first = get_cpu_clock();
        last_seq = 0;
        c = &t->entries[0];
        for (i = 0; i < t->nr_entries; i++, c++) {
@@ -512,7 +524,8 @@ static void *clock_thread_fn(void *data)
                unsigned long long clocks;
 
                clocks = t->entries[i - 1].tsc - t->entries[0].tsc;
-               log_info("cs: cpu%3d: %llu clocks seen\n", t->cpu, clocks);
+               log_info("cs: cpu%3d: %llu clocks seen, first %llu\n", t->cpu,
+                                                       clocks, first);
        }
 
        /*
@@ -520,9 +533,14 @@ static void *clock_thread_fn(void *data)
         * indefinitely. Check for that and return failure.
         */
        if (!t->entries[i - 1].tsc && !t->entries[0].tsc)
-               return (void *) 1;
+               goto err;
 
+       fio_cpuset_exit(&cpu_mask);
        return NULL;
+err:
+       fio_cpuset_exit(&cpu_mask);
+err_out:
+       return (void *) 1;
 }
 
 static int clock_cmp(const void *p1, const void *p2)
@@ -619,6 +637,8 @@ int fio_monotonic_clocktest(int debug)
 
        qsort(entries, tentries, sizeof(struct clock_entry), clock_cmp);
 
+       /* silence silly gcc */
+       prev = NULL;
        for (failed = i = 0; i < tentries; i++) {
                this = &entries[i];