X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Ftimeval.c;h=37b4353c7d2731e07a55a5957c1c799887e25294;hb=31ef9f5178dee18a40ce609aad406e925411eb06;hp=faf8e7bc8be277b1d3dac0b80d74822ac1f36cb3;hpb=c4f5d00bb76e01383ec3fbde31bc5c8f4e0a2b38;p=sliver-openvswitch.git diff --git a/lib/timeval.c b/lib/timeval.c index faf8e7bc8..37b4353c7 100644 --- a/lib/timeval.c +++ b/lib/timeval.c @@ -41,14 +41,12 @@ VLOG_DEFINE_THIS_MODULE(timeval); 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. */ }; @@ -67,11 +65,6 @@ static long long int deadline = LLONG_MAX; * 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); @@ -83,7 +76,6 @@ init_clock(struct clock *c, clockid_t id) { memset(c, 0, sizeof *c); c->id = id; - ovs_rwlock_init(&c->rwlock); xclock_gettime(c->id, &c->cache); } @@ -99,9 +91,6 @@ do_init_time(void) : 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. */ @@ -112,86 +101,16 @@ time_init(void) 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); } } @@ -268,7 +187,6 @@ time_alarm(unsigned int secs) assert_single_threaded(); time_init(); - time_refresh(); now = time_msec(); msecs = secs * 1000LL; @@ -286,8 +204,6 @@ time_alarm(unsigned int secs) * 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, @@ -295,18 +211,14 @@ 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); @@ -327,7 +239,6 @@ time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when, retval = -errno; } - time_refresh(); if (deadline <= time_msec()) { fatal_signal_handler(SIGALRM); if (retval < 0) { @@ -339,14 +250,6 @@ time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when, if (retval != -EINTR) { break; } - - if (!blocked && CACHE_TIME) { - block_sigalrm(&oldsigs); - blocked = true; - } - } - if (blocked) { - unblock_sigalrm(&oldsigs); } *last_wakeup = time_msec(); refresh_rusage(); @@ -354,27 +257,6 @@ time_poll(struct pollfd *pollfds, int n_pollfds, long long int timeout_when, 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) { @@ -570,6 +452,7 @@ timeval_stop_cb(struct unixctl_conn *conn, { 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);