struct clock {
clockid_t id; /* CLOCK_MONOTONIC or CLOCK_REALTIME. */
- struct ovs_rwlock rwlock; /* Mutual exclusion for 'cache'. */
/* Features for use by unit tests. Protected by 'rwlock'. */
+ struct ovs_rwlock rwlock;
struct timespec warp; /* Offset added for unit tests. */
bool stopped; /* Disables real-time updates if true. */
- /* Relevant only if CACHE_TIME is true. */
- volatile sig_atomic_t tick; /* Has the timer ticked? Set by signal. */
struct timespec cache; /* Last time read from kernel. */
};
* up. */
DEFINE_STATIC_PER_THREAD_DATA(long long int, last_wakeup, 0);
-static void set_up_timer(void);
-static void set_up_signal(int flags);
-static void sigalrm_handler(int);
-static void block_sigalrm(sigset_t *);
-static void unblock_sigalrm(const sigset_t *);
static void log_poll_interval(long long int last_wakeup);
static struct rusage *get_recent_rusage(void);
static void refresh_rusage(void);
{
memset(c, 0, sizeof *c);
c->id = id;
- ovs_rwlock_init(&c->rwlock);
xclock_gettime(c->id, &c->cache);
}
: CLOCK_REALTIME));
init_clock(&wall_clock, CLOCK_REALTIME);
boot_time = timespec_to_msec(&monotonic_clock.cache);
-
- set_up_signal(SA_RESTART);
- set_up_timer();
}
/* Initializes the timetracking module, if not already initialized. */
pthread_once(&once, do_init_time);
}
-static void
-set_up_signal(int flags)
-{
- struct sigaction sa;
-
- memset(&sa, 0, sizeof sa);
- sa.sa_handler = sigalrm_handler;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = flags;
- xsigaction(SIGALRM, &sa, NULL);
-}
-
-static void
-set_up_timer(void)
-{
- static timer_t timer_id; /* "static" to avoid apparent memory leak. */
- struct itimerspec itimer;
-
- if (!CACHE_TIME) {
- return;
- }
-
- if (timer_create(monotonic_clock.id, NULL, &timer_id)) {
- VLOG_FATAL("timer_create failed (%s)", ovs_strerror(errno));
- }
-
- itimer.it_interval.tv_sec = 0;
- itimer.it_interval.tv_nsec = TIME_UPDATE_INTERVAL * 1000 * 1000;
- itimer.it_value = itimer.it_interval;
-
- if (timer_settime(timer_id, 0, &itimer, NULL)) {
- VLOG_FATAL("timer_settime failed (%s)", ovs_strerror(errno));
- }
-}
-
-/* Set up the interval timer, to ensure that time advances even without calling
- * time_refresh().
- *
- * A child created with fork() does not inherit the parent's interval timer, so
- * this function needs to be called from the child after fork(). */
-void
-time_postfork(void)
-{
- assert_single_threaded();
- time_init();
- set_up_timer();
-}
-
-/* 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. If
- * CACHE_TIME is false, we will always refresh the current time so this
- * function has no effect. */
-void
-time_refresh(void)
-{
- monotonic_clock.tick = wall_clock.tick = true;
-}
-
static void
time_timespec__(struct clock *c, struct timespec *ts)
{
time_init();
- for (;;) {
- /* Use the cached time by preference, but fall through if there's been
- * a clock tick. */
- ovs_rwlock_rdlock(&c->rwlock);
- if (c->stopped || !c->tick) {
- timespec_add(ts, &c->cache, &c->warp);
- ovs_rwlock_unlock(&c->rwlock);
- return;
- }
- ovs_rwlock_unlock(&c->rwlock);
- /* Refresh the cache. */
- ovs_rwlock_wrlock(&c->rwlock);
- if (c->tick) {
- c->tick = false;
- xclock_gettime(c->id, &c->cache);
- }
+ if (!c->stopped) {
+ xclock_gettime(c->id, ts);
+ } else {
+ ovs_rwlock_rdlock(&c->rwlock);
+ timespec_add(ts, &c->cache, &c->warp);
ovs_rwlock_unlock(&c->rwlock);
}
}
assert_single_threaded();
time_init();
- time_refresh();
now = time_msec();
msecs = secs * 1000LL;
* timeout is reached. (Because of this property, this function will
* never return -EINTR.)
*
- * - As a side effect, refreshes the current time (like time_refresh()).
- *
* Stores the number of milliseconds elapsed during poll in '*elapsed'. */
int
time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when,
{
long long int *last_wakeup = last_wakeup_get();
long long int start;
- sigset_t oldsigs;
- bool blocked;
int retval;
time_init();
- time_refresh();
if (*last_wakeup) {
log_poll_interval(*last_wakeup);
}
coverage_clear();
start = time_msec();
- blocked = false;
timeout_when = MIN(timeout_when, deadline);
retval = -errno;
}
- time_refresh();
if (deadline <= time_msec()) {
fatal_signal_handler(SIGALRM);
if (retval < 0) {
if (retval != -EINTR) {
break;
}
-
- if (!blocked && CACHE_TIME) {
- block_sigalrm(&oldsigs);
- blocked = true;
- }
- }
- if (blocked) {
- unblock_sigalrm(&oldsigs);
}
*last_wakeup = time_msec();
refresh_rusage();
return retval;
}
-static void
-sigalrm_handler(int sig_nr OVS_UNUSED)
-{
- monotonic_clock.tick = wall_clock.tick = true;
-}
-
-static void
-block_sigalrm(sigset_t *oldsigs)
-{
- sigset_t sigalrm;
- sigemptyset(&sigalrm);
- sigaddset(&sigalrm, SIGALRM);
- xpthread_sigmask(SIG_BLOCK, &sigalrm, oldsigs);
-}
-
-static void
-unblock_sigalrm(const sigset_t *oldsigs)
-{
- xpthread_sigmask(SIG_SETMASK, oldsigs, NULL);
-}
-
long long int
timespec_to_msec(const struct timespec *ts)
{
{
ovs_rwlock_wrlock(&monotonic_clock.rwlock);
monotonic_clock.stopped = true;
+ xclock_gettime(monotonic_clock.id, &monotonic_clock.cache);
ovs_rwlock_unlock(&monotonic_clock.rwlock);
unixctl_command_reply(conn, NULL);
git://git.onelab.eu / sliver-openvswitch.git / blobdiff