#include <unistd.h>
#include <math.h>
#include <sys/time.h>
+#include <time.h>
#include "fio.h"
#include "smalloc.h"
#include "hash.h"
+#ifdef ARCH_HAVE_CPU_CLOCK
static unsigned long cycles_per_usec;
-static struct timeval last_tv;
static unsigned long last_cycles;
+#endif
+static struct timeval last_tv;
static int last_tv_valid;
static struct timeval *fio_tv;
int fio_gtod_offload = 0;
int fio_gtod_cpu = -1;
+static pthread_t gtod_thread;
-enum fio_cs fio_clock_source = CS_GTOD;
+enum fio_cs fio_clock_source = FIO_PREFERRED_CLOCK_SOURCE;
#ifdef FIO_DEBUG_TIME
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
log_err("fio: clock_gettime fails\n");
assert(0);
}
memcpy(&last_tv, tp, sizeof(*tp));
}
+#ifdef ARCH_HAVE_CPU_CLOCK
static unsigned long get_cycles_per_usec(void)
{
struct timeval s, e;
return c_e - c_s;
}
-void fio_clock_init(void)
+static void calibrate_cpu_clock(void)
{
double delta, mean, S;
unsigned long avg, cycles[10];
int i, samples;
- last_tv_valid = 0;
-
cycles[0] = get_cycles_per_usec();
S = delta = mean = 0.0;
for (i = 0; i < 10; i++) {
for (i = 0; i < 10; i++) {
double this = cycles[i];
- if ((max(this, mean) - min(this, mean)) > S)
+ if ((fmax(this, mean) - fmin(this, mean)) > S)
continue;
samples++;
avg += this;
dprint(FD_TIME, "mean=%f, S=%f\n", mean, S);
cycles_per_usec = avg;
+
+}
+#else
+static void calibrate_cpu_clock(void)
+{
+}
+#endif
+
+void fio_clock_init(void)
+{
+ last_tv_valid = 0;
+ calibrate_cpu_clock();
}
void fio_gtod_init(void)
assert(fio_tv);
}
-void fio_gtod_update(void)
+static void fio_gtod_update(void)
{
gettimeofday(fio_tv, NULL);
}
+
+static void *gtod_thread_main(void *data)
+{
+ struct fio_mutex *mutex = data;
+
+ fio_mutex_up(mutex);
+
+ /*
+ * As long as we have jobs around, update the clock. It would be nice
+ * to have some way of NOT hammering that CPU with gettimeofday(),
+ * but I'm not sure what to use outside of a simple CPU nop to relax
+ * it - we don't want to lose precision.
+ */
+ while (threads) {
+ fio_gtod_update();
+ nop;
+ }
+
+ return NULL;
+}
+
+int fio_start_gtod_thread(void)
+{
+ struct fio_mutex *mutex;
+ pthread_attr_t attr;
+ int ret;
+
+ mutex = fio_mutex_init(FIO_MUTEX_LOCKED);
+ if (!mutex)
+ return 1;
+
+ pthread_attr_init(&attr);
+ pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN);
+ ret = pthread_create(>od_thread, &attr, gtod_thread_main, NULL);
+ pthread_attr_destroy(&attr);
+ if (ret) {
+ log_err("Can't create gtod thread: %s\n", strerror(ret));
+ goto err;
+ }
+
+ ret = pthread_detach(gtod_thread);
+ if (ret) {
+ log_err("Can't detatch gtod thread: %s\n", strerror(ret));
+ goto err;
+ }
+
+ dprint(FD_MUTEX, "wait on startup_mutex\n");
+ fio_mutex_down(mutex);
+ dprint(FD_MUTEX, "done waiting on startup_mutex\n");
+err:
+ fio_mutex_remove(mutex);
+ return ret;
+}