#include "coverage.h"
#include "fatal-signal.h"
#include "util.h"
-
#include "vlog.h"
-#define THIS_MODULE VLM_timeval
-/* Initialized? */
-static bool inited;
+VLOG_DEFINE_THIS_MODULE(timeval)
+
+/* The clock to use for measuring time intervals. This is CLOCK_MONOTONIC by
+ * preference, but on systems that don't have a monotonic clock we fall back
+ * to CLOCK_REALTIME. */
+static clockid_t monotonic_clock;
-/* Has a timer tick occurred? */
-static volatile sig_atomic_t tick;
+/* Has a timer tick occurred?
+ *
+ * We initialize these to true to force time_init() to get called on the first
+ * call to time_msec() or another function that queries the current time. */
+static volatile sig_atomic_t wall_tick = true;
+static volatile sig_atomic_t monotonic_tick = true;
/* The current time, as of the last refresh. */
-static struct timeval now;
+static struct timespec wall_time;
+static struct timespec monotonic_time;
/* Time at which to die with SIGALRM (if not TIME_MIN). */
static time_t deadline = TIME_MIN;
static void set_up_timer(void);
static void set_up_signal(int flags);
static void sigalrm_handler(int);
-static void refresh_if_ticked(void);
+static void refresh_wall_if_ticked(void);
+static void refresh_monotonic_if_ticked(void);
static time_t time_add(time_t, time_t);
static void block_sigalrm(sigset_t *);
static void unblock_sigalrm(const sigset_t *);
static void log_poll_interval(long long int last_wakeup,
const struct rusage *last_rusage);
-/* Initializes the timetracking module. */
-void
+/* Initializes the timetracking module.
+ *
+ * It is not necessary to call this function directly, because other time
+ * functions will call it automatically, but it doesn't hurt. */
+static void
time_init(void)
{
+ static bool inited;
if (inited) {
return;
}
+ inited = true;
coverage_init();
- inited = true;
- gettimeofday(&now, NULL);
- tick = false;
+ if (!clock_gettime(CLOCK_MONOTONIC, &monotonic_time)) {
+ monotonic_clock = CLOCK_MONOTONIC;
+ } else {
+ monotonic_clock = CLOCK_REALTIME;
+ VLOG_DBG("monotonic timer not available");
+ }
set_up_signal(SA_RESTART);
set_up_timer();
void
time_disable_restart(void)
{
+ time_init();
set_up_signal(0);
}
void
time_enable_restart(void)
{
+ time_init();
set_up_signal(SA_RESTART);
}
static void
set_up_timer(void)
{
- struct itimerval itimer;
+ static timer_t timer_id; /* "static" to avoid apparent memory leak. */
+ struct itimerspec itimer;
+
+ if (timer_create(monotonic_clock, NULL, &timer_id)) {
+ ovs_fatal(errno, "timer_create failed");
+ }
itimer.it_interval.tv_sec = 0;
- itimer.it_interval.tv_usec = TIME_UPDATE_INTERVAL * 1000;
+ itimer.it_interval.tv_nsec = TIME_UPDATE_INTERVAL * 1000 * 1000;
itimer.it_value = itimer.it_interval;
- if (setitimer(ITIMER_REAL, &itimer, NULL)) {
- ovs_fatal(errno, "setitimer failed");
+
+ if (timer_settime(timer_id, 0, &itimer, NULL)) {
+ ovs_fatal(errno, "timer_settime failed");
}
}
void
time_postfork(void)
{
+ time_init();
set_up_timer();
}
+static void
+refresh_wall(void)
+{
+ time_init();
+ clock_gettime(CLOCK_REALTIME, &wall_time);
+ wall_tick = false;
+}
+
+static void
+refresh_monotonic(void)
+{
+ time_init();
+
+ if (monotonic_clock == CLOCK_MONOTONIC) {
+ clock_gettime(monotonic_clock, &monotonic_time);
+ } else {
+ refresh_wall_if_ticked();
+ monotonic_time = wall_time;
+ }
+
+ monotonic_tick = false;
+}
+
/* Forces a refresh of the current time from the kernel. It is not usually
* necessary to call this function, since the time will be refreshed
* automatically at least every TIME_UPDATE_INTERVAL milliseconds. */
void
time_refresh(void)
{
- gettimeofday(&now, NULL);
- tick = false;
+ wall_tick = monotonic_tick = true;
}
-/* Returns the current time, in seconds. */
+/* Returns a monotonic timer, in seconds. */
time_t
time_now(void)
{
- refresh_if_ticked();
- return now.tv_sec;
+ refresh_monotonic_if_ticked();
+ return monotonic_time.tv_sec;
}
-/* Returns the current time, in ms (within TIME_UPDATE_INTERVAL ms). */
+/* Same as time_now() except does not write to static variables, for use in
+ * signal handlers. */
+static time_t
+time_now_sig(void)
+{
+ struct timespec cur_time;
+
+ clock_gettime(monotonic_clock, &cur_time);
+ return cur_time.tv_sec;
+}
+
+/* Returns the current time, in seconds. */
+time_t
+time_wall(void)
+{
+ refresh_wall_if_ticked();
+ return wall_time.tv_sec;
+}
+
+/* Returns a monotonic timer, in ms (within TIME_UPDATE_INTERVAL ms). */
long long int
time_msec(void)
{
- refresh_if_ticked();
- return timeval_to_msec(&now);
+ refresh_monotonic_if_ticked();
+ return timespec_to_msec(&monotonic_time);
+}
+
+/* Returns the current time, in ms (within TIME_UPDATE_INTERVAL ms). */
+long long int
+time_wall_msec(void)
+{
+ refresh_wall_if_ticked();
+ return timespec_to_msec(&wall_time);
+}
+
+/* Stores a monotonic timer, accurate within TIME_UPDATE_INTERVAL ms, into
+ * '*ts'. */
+void
+time_timespec(struct timespec *ts)
+{
+ refresh_monotonic_if_ticked();
+ *ts = monotonic_time;
}
/* Stores the current time, accurate within TIME_UPDATE_INTERVAL ms, into
- * '*tv'. */
+ * '*ts'. */
void
-time_timeval(struct timeval *tv)
+time_wall_timespec(struct timespec *ts)
{
- refresh_if_ticked();
- *tv = now;
+ refresh_wall_if_ticked();
+ *ts = wall_time;
}
/* Configures the program to die with SIGALRM 'secs' seconds from now, if
static void
sigalrm_handler(int sig_nr)
{
- tick = true;
- if (deadline != TIME_MIN && time(0) > deadline) {
+ wall_tick = true;
+ monotonic_tick = true;
+ if (deadline != TIME_MIN && time_now_sig() > deadline) {
fatal_signal_handler(sig_nr);
}
}
static void
-refresh_if_ticked(void)
+refresh_wall_if_ticked(void)
{
- assert(inited);
- if (tick) {
- time_refresh();
+ if (wall_tick) {
+ refresh_wall();
+ }
+}
+
+static void
+refresh_monotonic_if_ticked(void)
+{
+ if (monotonic_tick) {
+ refresh_monotonic();
}
}
}
}
+long long int
+timespec_to_msec(const struct timespec *ts)
+{
+ return (long long int) ts->tv_sec * 1000 + ts->tv_nsec / (1000 * 1000);
+}
+
long long int
timeval_to_msec(const struct timeval *tv)
{