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#include <sys/time.h>
#include <time.h>
#include "fio.h"
#include "lib/seqlock.h"
#include "smalloc.h"
struct fio_ts *fio_ts;
int fio_gtod_offload = 0;
static pthread_t gtod_thread;
static os_cpu_mask_t fio_gtod_cpumask;
void fio_gtod_init(void)
{
if (fio_ts)
return;
fio_ts = smalloc(sizeof(*fio_ts));
}
static void fio_gtod_update(void)
{
struct timeval __tv;
if (!fio_ts)
return;
gettimeofday(&__tv, NULL);
write_seqlock_begin(&fio_ts->seqlock);
fio_ts->ts.tv_sec = __tv.tv_sec;
fio_ts->ts.tv_nsec = __tv.tv_usec * 1000;
write_seqlock_end(&fio_ts->seqlock);
}
struct gtod_cpu_data {
struct fio_sem *sem;
unsigned int cpu;
};
static void *gtod_thread_main(void *data)
{
struct fio_sem *sem = data;
int ret;
ret = fio_setaffinity(gettid(), fio_gtod_cpumask);
fio_sem_up(sem);
if (ret == -1) {
log_err("gtod: setaffinity failed\n");
return NULL;
}
/*
* 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 (nr_segments) {
fio_gtod_update();
nop;
}
return NULL;
}
int fio_start_gtod_thread(void)
{
struct fio_sem *sem;
pthread_attr_t attr;
int ret;
sem = fio_sem_init(FIO_SEM_LOCKED);
if (!sem)
return 1;
pthread_attr_init(&attr);
pthread_attr_setstacksize(&attr, 2 * PTHREAD_STACK_MIN);
ret = pthread_create(>od_thread, &attr, gtod_thread_main, sem);
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 detach gtod thread: %s\n", strerror(ret));
goto err;
}
dprint(FD_MUTEX, "wait on startup_sem\n");
fio_sem_down(sem);
dprint(FD_MUTEX, "done waiting on startup_sem\n");
err:
fio_sem_remove(sem);
return ret;
}
void fio_gtod_set_cpu(unsigned int cpu)
{
#ifdef FIO_HAVE_CPU_AFFINITY
fio_cpu_set(&fio_gtod_cpumask, cpu);
#endif
}
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