static unsigned long cycles_per_usec;
static unsigned long inv_cycles_per_usec;
static uint64_t max_cycles_for_mult;
+static unsigned long long cycles_start, cycles_wrap;
#endif
int tsc_reliable = 0;
int last_tv_valid;
int warned;
};
+#ifdef ARCH_HAVE_CPU_CLOCK
#ifdef CONFIG_TLS_THREAD
static __thread struct tv_valid static_tv_valid;
#else
static pthread_key_t tv_tls_key;
#endif
+#endif
enum fio_cs fio_clock_source = FIO_PREFERRED_CLOCK_SOURCE;
int fio_clock_source_set = 0;
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:
#ifdef ARCH_HAVE_CPU_CLOCK
case CS_CPUCLOCK: {
uint64_t usecs, t;
+ struct tv_valid *tv;
+
+#ifdef CONFIG_TLS_THREAD
+ tv = &static_tv_valid;
+#else
+ tv = pthread_getspecific(tv_tls_key);
+#endif
t = get_cpu_clock();
- if (t < tv->last_cycles && tv->last_tv_valid &&
- !tv->warned) {
- log_err("fio: CPU clock going back in time\n");
+ if (t < cycles_start && !cycles_wrap)
+ cycles_wrap = 1;
+ else if (cycles_wrap && t >= cycles_start && !tv->warned) {
+ log_err("fio: double CPU clock wrap\n");
tv->warned = 1;
}
+ t -= cycles_start;
tv->last_cycles = t;
tv->last_tv_valid = 1;
#ifdef ARCH_CPU_CLOCK_CYCLES_PER_USEC
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);
+ cycles_start = get_cpu_clock();
+ dprint(FD_TIME, "cycles_start=%llu\n", cycles_start);
return 0;
}
#else
* runs at a constant rate and is synced across CPU cores.
*/
if (tsc_reliable) {
- if (!fio_clock_source_set)
+ if (!fio_clock_source_set && !fio_monotonic_clocktest(0))
fio_clock_source = CS_CPUCLOCK;
} else if (fio_clock_source == CS_CPUCLOCK)
log_info("fio: clocksource=cpu may not be reliable\n");
#if defined(FIO_HAVE_CPU_AFFINITY) && defined(ARCH_HAVE_CPU_CLOCK) && \
defined(CONFIG_SFAA)
-#define CLOCK_ENTRIES 100000
+#define CLOCK_ENTRIES_DEBUG 100000
+#define CLOCK_ENTRIES_TEST 10000
struct clock_entry {
uint32_t seq;
struct clock_thread {
pthread_t thread;
int cpu;
+ int debug;
pthread_mutex_t lock;
pthread_mutex_t started;
+ unsigned long nr_entries;
uint32_t *seq;
struct clock_entry *entries;
};
last_seq = 0;
c = &t->entries[0];
- for (i = 0; i < CLOCK_ENTRIES; i++, c++) {
+ for (i = 0; i < t->nr_entries; i++, c++) {
uint32_t seq;
uint64_t tsc;
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);
+ if (t->debug) {
+ 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);
+ }
/*
* The most common platform clock breakage is returning zero
return c1->seq - c2->seq;
}
-int fio_monotonic_clocktest(void)
+int fio_monotonic_clocktest(int debug)
{
struct clock_thread *cthreads;
unsigned int nr_cpus = cpus_online();
struct clock_entry *entries;
- unsigned long tentries, failed = 0;
+ unsigned long nr_entries, 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");
+ if (debug) {
+ log_info("cs: reliable_tsc: %s\n", tsc_reliable ? "yes" : "no");
#ifdef FIO_INC_DEBUG
- fio_debug |= 1U << FD_TIME;
+ fio_debug |= 1U << FD_TIME;
#endif
+ nr_entries = CLOCK_ENTRIES_DEBUG;
+ } else
+ nr_entries = CLOCK_ENTRIES_TEST;
+
calibrate_cpu_clock();
+
+ if (debug) {
#ifdef FIO_INC_DEBUG
- fio_debug &= ~(1U << FD_TIME);
+ fio_debug &= ~(1U << FD_TIME);
#endif
+ }
cthreads = malloc(nr_cpus * sizeof(struct clock_thread));
- tentries = CLOCK_ENTRIES * nr_cpus;
+ tentries = nr_entries * nr_cpus;
entries = malloc(tentries * sizeof(struct clock_entry));
- log_info("cs: Testing %u CPUs\n", nr_cpus);
+ if (debug)
+ log_info("cs: Testing %u CPUs\n", nr_cpus);
for (i = 0; i < nr_cpus; i++) {
struct clock_thread *t = &cthreads[i];
t->cpu = i;
+ t->debug = debug;
t->seq = &seq;
- t->entries = &entries[i * CLOCK_ENTRIES];
+ t->nr_entries = nr_entries;
+ t->entries = &entries[i * nr_entries];
pthread_mutex_init(&t->lock, NULL);
pthread_mutex_init(&t->started, NULL);
pthread_mutex_lock(&t->lock);
free(cthreads);
if (failed) {
- log_err("Clocksource test: %lu threads failed\n", failed);
+ if (debug)
+ log_err("Clocksource test: %lu threads failed\n", failed);
goto err;
}
if (prev->tsc > this->tsc) {
uint64_t diff = prev->tsc - this->tsc;
+ if (!debug) {
+ failed++;
+ break;
+ }
+
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);
prev = this;
}
- if (failed)
- log_info("cs: Failed: %lu\n", failed);
- else
- log_info("cs: Pass!\n");
-
+ if (debug) {
+ 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)
+int fio_monotonic_clocktest(int debug)
{
- log_info("cs: current platform does not support CPU clocks\n");
- return 0;
+ if (debug)
+ log_info("cs: current platform does not support CPU clocks\n");
+ return 1;
}
#endif