diff --git a/gst/gstsystemclock.c b/gst/gstsystemclock.c
index b635d12643b21328df19014a3e67042c7493f9aa..2c71489cfa2bbd20b19847e900bebc10c56b8d23 100644 (file)
--- a/gst/gstsystemclock.c
+++ b/gst/gstsystemclock.c
* async notifications to implement their own callback methods or blocking
* wait operations.
*
- * Last reviewed on 2005-10-28 (0.9.4)
+ * Last reviewed on 2006-03-08 (0.10.4)
*/
#include "gst_private.h"
#include "gstinfo.h"
-
#include "gstsystemclock.h"
+#include "gstenumtypes.h"
+#include "gstpoll.h"
+#include "gstutils.h"
+#include "glib-compat-private.h"
+
+#include <errno.h>
+
+#ifdef G_OS_WIN32
+# define WIN32_LEAN_AND_MEAN /* prevents from including too many things */
+# include <windows.h> /* QueryPerformance* stuff */
+# undef WIN32_LEAN_AND_MEAN
+# define EWOULDBLOCK EAGAIN /* This is just to placate gcc */
+#endif /* G_OS_WIN32 */
+
+#define GET_ENTRY_STATUS(e) ((GstClockReturn) g_atomic_int_get(&GST_CLOCK_ENTRY_STATUS(e)))
+#define SET_ENTRY_STATUS(e,val) (g_atomic_int_set(&GST_CLOCK_ENTRY_STATUS(e),(val)))
+#define CAS_ENTRY_STATUS(e,old,val) (G_ATOMIC_INT_COMPARE_AND_EXCHANGE(\
+ (&GST_CLOCK_ENTRY_STATUS(e)), (old), (val)))
+
+/* Define this to get some extra debug about jitter from each clock_wait */
+#undef WAIT_DEBUGGING
+
+struct _GstSystemClockPrivate
+{
+ GstClockType clock_type;
+ GstPoll *timer;
+ gint wakeup_count; /* the number of entries with a pending wakeup */
+ gboolean async_wakeup; /* if the wakeup was because of a async list change */
+
+#ifdef G_OS_WIN32
+ LARGE_INTEGER start;
+ LARGE_INTEGER frequency;
+#endif /* G_OS_WIN32 */
+};
+
+#define GST_SYSTEM_CLOCK_GET_PRIVATE(obj) \
+ (G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_SYSTEM_CLOCK, \
+ GstSystemClockPrivate))
+
+#ifdef HAVE_POSIX_TIMERS
+# ifdef HAVE_MONOTONIC_CLOCK
+# define DEFAULT_CLOCK_TYPE GST_CLOCK_TYPE_MONOTONIC
+# else
+# define DEFAULT_CLOCK_TYPE GST_CLOCK_TYPE_REALTIME
+# endif
+#else
+#define DEFAULT_CLOCK_TYPE GST_CLOCK_TYPE_REALTIME
+#endif
+
+enum
+{
+ PROP_0,
+ PROP_CLOCK_TYPE,
+ /* FILL ME */
+};
/* the one instance of the systemclock */
static GstClock *_the_system_clock = NULL;
-static void gst_system_clock_class_init (GstSystemClockClass * klass);
-static void gst_system_clock_init (GstSystemClock * clock);
static void gst_system_clock_dispose (GObject * object);
+static void gst_system_clock_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec);
+static void gst_system_clock_get_property (GObject * object, guint prop_id,
+ GValue * value, GParamSpec * pspec);
static GstClockTime gst_system_clock_get_internal_time (GstClock * clock);
static guint64 gst_system_clock_get_resolution (GstClock * clock);
-static GstClockReturn gst_system_clock_id_wait (GstClock * clock,
- GstClockEntry * entry);
-static GstClockReturn gst_system_clock_id_wait_unlocked
- (GstClock * clock, GstClockEntry * entry);
+static GstClockReturn gst_system_clock_id_wait_jitter (GstClock * clock,
+ GstClockEntry * entry, GstClockTimeDiff * jitter);
+static GstClockReturn gst_system_clock_id_wait_jitter_unlocked
+ (GstClock * clock, GstClockEntry * entry, GstClockTimeDiff * jitter,
+ gboolean restart);
static GstClockReturn gst_system_clock_id_wait_async (GstClock * clock,
GstClockEntry * entry);
static void gst_system_clock_id_unschedule (GstClock * clock,
GstClockEntry * entry);
static void gst_system_clock_async_thread (GstClock * clock);
+static gboolean gst_system_clock_start_async (GstSystemClock * clock);
+static void gst_system_clock_add_wakeup (GstSystemClock * sysclock);
static GStaticMutex _gst_sysclock_mutex = G_STATIC_MUTEX_INIT;
/* static guint gst_system_clock_signals[LAST_SIGNAL] = { 0 }; */
-GType
-gst_system_clock_get_type (void)
-{
- static GType clock_type = 0;
-
- if (!clock_type) {
- static const GTypeInfo clock_info = {
- sizeof (GstSystemClockClass),
- NULL,
- NULL,
- (GClassInitFunc) gst_system_clock_class_init,
- NULL,
- NULL,
- sizeof (GstSystemClock),
- 0,
- (GInstanceInitFunc) gst_system_clock_init,
- NULL
- };
-
- clock_type = g_type_register_static (GST_TYPE_CLOCK, "GstSystemClock",
- &clock_info, 0);
- }
- return clock_type;
-}
+G_DEFINE_TYPE (GstSystemClock, gst_system_clock, GST_TYPE_CLOCK);
static void
gst_system_clock_class_init (GstSystemClockClass * klass)
{
GObjectClass *gobject_class;
- GstObjectClass *gstobject_class;
GstClockClass *gstclock_class;
gobject_class = (GObjectClass *) klass;
- gstobject_class = (GstObjectClass *) klass;
gstclock_class = (GstClockClass *) klass;
- parent_class = g_type_class_ref (GST_TYPE_CLOCK);
+ parent_class = g_type_class_peek_parent (klass);
+
+ g_type_class_add_private (klass, sizeof (GstSystemClockPrivate));
gobject_class->dispose = gst_system_clock_dispose;
+ gobject_class->set_property = gst_system_clock_set_property;
+ gobject_class->get_property = gst_system_clock_get_property;
+
+ g_object_class_install_property (gobject_class, PROP_CLOCK_TYPE,
+ g_param_spec_enum ("clock-type", "Clock type",
+ "The type of underlying clock implementation used",
+ GST_TYPE_CLOCK_TYPE, DEFAULT_CLOCK_TYPE,
+ G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gstclock_class->get_internal_time = gst_system_clock_get_internal_time;
gstclock_class->get_resolution = gst_system_clock_get_resolution;
- gstclock_class->wait = gst_system_clock_id_wait;
+ gstclock_class->wait_jitter = gst_system_clock_id_wait_jitter;
gstclock_class->wait_async = gst_system_clock_id_wait_async;
gstclock_class->unschedule = gst_system_clock_id_unschedule;
}
static void
gst_system_clock_init (GstSystemClock * clock)
{
- GError *error = NULL;
-
- GST_CLOCK_FLAGS (clock) =
+ GST_OBJECT_FLAG_SET (clock,
GST_CLOCK_FLAG_CAN_DO_SINGLE_SYNC |
GST_CLOCK_FLAG_CAN_DO_SINGLE_ASYNC |
GST_CLOCK_FLAG_CAN_DO_PERIODIC_SYNC |
- GST_CLOCK_FLAG_CAN_DO_PERIODIC_ASYNC;
+ GST_CLOCK_FLAG_CAN_DO_PERIODIC_ASYNC);
- GST_OBJECT_LOCK (clock);
- clock->thread = g_thread_create ((GThreadFunc) gst_system_clock_async_thread,
- clock, TRUE, &error);
- if (error)
- goto no_thread;
+ clock->priv = GST_SYSTEM_CLOCK_GET_PRIVATE (clock);
- /* wait for it to spin up */
- GST_CLOCK_WAIT (clock);
- GST_OBJECT_UNLOCK (clock);
- return;
+ clock->priv->clock_type = DEFAULT_CLOCK_TYPE;
+ clock->priv->timer = gst_poll_new_timer ();
-no_thread:
- {
- g_warning ("could not create async clock thread: %s", error->message);
- GST_OBJECT_UNLOCK (clock);
- }
+#ifdef G_OS_WIN32
+ QueryPerformanceFrequency (&clock->priv->frequency);
+ /* can be 0 if the hardware does not have hardware support */
+ if (clock->priv->frequency.QuadPart != 0)
+ /* we take a base time so that time starts from 0 to ease debugging */
+ QueryPerformanceCounter (&clock->priv->start);
+#endif /* G_OS_WIN32 */
+
+#if 0
+ /* Uncomment this to start the async clock thread straight away */
+ GST_OBJECT_LOCK (clock);
+ gst_system_clock_start_async (clock);
+ GST_OBJECT_UNLOCK (clock);
+#endif
}
static void
gst_system_clock_dispose (GObject * object)
{
GstClock *clock = (GstClock *) object;
-
- GstSystemClock *sysclock = GST_SYSTEM_CLOCK (clock);
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
GList *entries;
/* else we have to stop the thread */
GstClockEntry *entry = (GstClockEntry *) entries->data;
GST_CAT_DEBUG (GST_CAT_CLOCK, "unscheduling entry %p", entry);
- entry->status = GST_CLOCK_UNSCHEDULED;
+ SET_ENTRY_STATUS (entry, GST_CLOCK_UNSCHEDULED);
}
- g_list_free (clock->entries);
- clock->entries = NULL;
GST_CLOCK_BROADCAST (clock);
+ gst_system_clock_add_wakeup (sysclock);
GST_OBJECT_UNLOCK (clock);
if (sysclock->thread)
sysclock->thread = NULL;
GST_CAT_DEBUG (GST_CAT_CLOCK, "joined thread");
+ g_list_foreach (clock->entries, (GFunc) gst_clock_id_unref, NULL);
+ g_list_free (clock->entries);
+ clock->entries = NULL;
+
+ gst_poll_free (sysclock->priv->timer);
+
G_OBJECT_CLASS (parent_class)->dispose (object);
if (_the_system_clock == clock) {
}
}
+static void
+gst_system_clock_set_property (GObject * object, guint prop_id,
+ const GValue * value, GParamSpec * pspec)
+{
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK (object);
+
+ switch (prop_id) {
+ case PROP_CLOCK_TYPE:
+ sysclock->priv->clock_type = (GstClockType) g_value_get_enum (value);
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "clock-type set to %d",
+ sysclock->priv->clock_type);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
+static void
+gst_system_clock_get_property (GObject * object, guint prop_id, GValue * value,
+ GParamSpec * pspec)
+{
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK (object);
+
+ switch (prop_id) {
+ case PROP_CLOCK_TYPE:
+ g_value_set_enum (value, sysclock->priv->clock_type);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+ break;
+ }
+}
+
/**
* gst_system_clock_obtain:
*
* clock will be increased so you need to unref the clock after
* usage.
*
- * Returns: the default clock.
+ * Returns: (transfer full): the default clock.
*
* MT safe.
*/
/* we created the global clock; take ownership so
* we can hand out instances later */
- gst_object_ref (clock);
- gst_object_sink (GST_OBJECT (clock));
+ gst_object_ref_sink (clock);
_the_system_clock = clock;
g_static_mutex_unlock (&_gst_sysclock_mutex);
return clock;
}
+static void
+gst_system_clock_remove_wakeup (GstSystemClock * sysclock)
+{
+ g_return_if_fail (sysclock->priv->wakeup_count > 0);
+
+ sysclock->priv->wakeup_count--;
+ if (sysclock->priv->wakeup_count == 0) {
+ /* read the control socket byte when we removed the last wakeup count */
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "reading control");
+ while (!gst_poll_read_control (sysclock->priv->timer)) {
+ g_warning ("gstsystemclock: read control failed, trying again\n");
+ }
+ GST_CLOCK_BROADCAST (sysclock);
+ }
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "wakeup count %d",
+ sysclock->priv->wakeup_count);
+}
+
+static void
+gst_system_clock_add_wakeup (GstSystemClock * sysclock)
+{
+ /* only write the control socket for the first wakeup */
+ if (sysclock->priv->wakeup_count == 0) {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "writing control");
+ while (!gst_poll_write_control (sysclock->priv->timer)) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR) {
+ g_warning
+ ("gstsystemclock: write control failed in wakeup_async, trying again: %d:%s\n",
+ errno, g_strerror (errno));
+ } else {
+ g_critical
+ ("gstsystemclock: write control failed in wakeup_async: %d:%s\n",
+ errno, g_strerror (errno));
+ return;
+ }
+ }
+ }
+ sysclock->priv->wakeup_count++;
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "wakeup count %d",
+ sysclock->priv->wakeup_count);
+}
+
+static void
+gst_system_clock_wait_wakeup (GstSystemClock * sysclock)
+{
+ while (sysclock->priv->wakeup_count > 0) {
+ GST_CLOCK_WAIT (sysclock);
+ }
+}
+
/* this thread reads the sorted clock entries from the queue.
*
* It waits on each of them and fires the callback when the timeout occurs.
*
- * When an entry in the queue was canceled, it is simply skipped.
+ * When an entry in the queue was canceled before we wait for it, it is
+ * simply skipped.
*
* When waiting for an entry, it can become canceled, in that case we don't
* call the callback but move to the next item in the queue.
static void
gst_system_clock_async_thread (GstClock * clock)
{
- GstSystemClock *sysclock = GST_SYSTEM_CLOCK (clock);
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
GST_CAT_DEBUG (GST_CAT_CLOCK, "enter system clock thread");
GST_OBJECT_LOCK (clock);
/* now enter our (almost) infinite loop */
while (!sysclock->stopping) {
GstClockEntry *entry;
+ GstClockTime requested;
GstClockReturn res;
/* check if something to be done */
goto exit;
}
+ /* see if we have a pending wakeup because the order of the list
+ * changed. */
+ if (sysclock->priv->async_wakeup) {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "clear async wakeup");
+ gst_system_clock_remove_wakeup (sysclock);
+ sysclock->priv->async_wakeup = FALSE;
+ }
+
/* pick the next entry */
entry = clock->entries->data;
- /* if it was unscheduled, just move on to the next entry */
- if (entry->status == GST_CLOCK_UNSCHEDULED) {
- GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p was unscheduled", entry);
- goto next_entry;
- }
+ GST_OBJECT_UNLOCK (clock);
+
+ requested = entry->time;
/* now wait for the entry, we already hold the lock */
- res = gst_system_clock_id_wait_unlocked (clock, (GstClockID) entry);
+ res =
+ gst_system_clock_id_wait_jitter_unlocked (clock, (GstClockID) entry,
+ NULL, FALSE);
+
+ GST_OBJECT_LOCK (clock);
switch (res) {
case GST_CLOCK_UNSCHEDULED:
{
/* entry timed out normally, fire the callback and move to the next
* entry */
- GST_CAT_DEBUG (GST_CAT_CLOCK, "async entry %p unlocked", entry);
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "async entry %p timed out", entry);
if (entry->func) {
/* unlock before firing the callback */
GST_OBJECT_UNLOCK (clock);
GST_OBJECT_LOCK (clock);
}
if (entry->type == GST_CLOCK_ENTRY_PERIODIC) {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "updating periodic entry %p", entry);
/* adjust time now */
- entry->time += entry->interval;
+ entry->time = requested + entry->interval;
/* and resort the list now */
clock->entries =
g_list_sort (clock->entries, gst_clock_id_compare_func);
/* and restart */
continue;
} else {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "moving to next entry");
goto next_entry;
}
}
* was canceled. Whatever it is, pick the head entry of the list and
* continue waiting. */
GST_CAT_DEBUG (GST_CAT_CLOCK, "async entry %p needs restart", entry);
+
+ /* we set the entry back to the OK state. This is needed so that the
+ * _unschedule() code can see if an entry is currently being waited
+ * on (when its state is BUSY). */
+ SET_ENTRY_STATUS (entry, GST_CLOCK_OK);
continue;
default:
GST_CAT_DEBUG (GST_CAT_CLOCK,
GST_CAT_DEBUG (GST_CAT_CLOCK, "exit system clock thread");
}
+#ifdef HAVE_POSIX_TIMERS
+static inline clockid_t
+clock_type_to_posix_id (GstClockType clock_type)
+{
+#ifdef HAVE_MONOTONIC_CLOCK
+ if (clock_type == GST_CLOCK_TYPE_MONOTONIC)
+ return CLOCK_MONOTONIC;
+ else
+#endif
+ return CLOCK_REALTIME;
+}
+#endif
+
/* MT safe */
static GstClockTime
gst_system_clock_get_internal_time (GstClock * clock)
{
- GTimeVal timeval;
+#ifdef G_OS_WIN32
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+
+ if (sysclock->priv->frequency.QuadPart != 0) {
+ LARGE_INTEGER now;
- g_get_current_time (&timeval);
+ /* we prefer the highly accurate performance counters on windows */
+ QueryPerformanceCounter (&now);
- return GST_TIMEVAL_TO_TIME (timeval);
+ return gst_util_uint64_scale (now.QuadPart - sysclock->priv->start.QuadPart,
+ GST_SECOND, sysclock->priv->frequency.QuadPart);
+ } else
+#endif /* G_OS_WIN32 */
+#if !defined HAVE_POSIX_TIMERS
+ {
+ GTimeVal timeval;
+
+ g_get_current_time (&timeval);
+
+ return GST_TIMEVAL_TO_TIME (timeval);
+ }
+#else
+ {
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+ clockid_t ptype;
+ struct timespec ts;
+
+ ptype = clock_type_to_posix_id (sysclock->priv->clock_type);
+
+ if (G_UNLIKELY (clock_gettime (ptype, &ts)))
+ return GST_CLOCK_TIME_NONE;
+
+ return GST_TIMESPEC_TO_TIME (ts);
+ }
+#endif
}
static guint64
gst_system_clock_get_resolution (GstClock * clock)
{
- return 1 * GST_USECOND;
+#ifdef G_OS_WIN32
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+
+ if (sysclock->priv->frequency.QuadPart != 0) {
+ return GST_SECOND / sysclock->priv->frequency.QuadPart;
+ } else
+#endif /* G_OS_WIN32 */
+#ifdef HAVE_POSIX_TIMERS
+ {
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+ clockid_t ptype;
+ struct timespec ts;
+
+ ptype = clock_type_to_posix_id (sysclock->priv->clock_type);
+
+ if (G_UNLIKELY (clock_getres (ptype, &ts)))
+ return GST_CLOCK_TIME_NONE;
+
+ return GST_TIMESPEC_TO_TIME (ts);
+ }
+#else
+ {
+ return 1 * GST_USECOND;
+ }
+#endif
}
/* synchronously wait on the given GstClockEntry.
*
- * We do this by blocking on the global clock GCond variable with
- * the requested time as a timeout. This allows us to unblock the
- * entry by signaling the GCond variable.
+ * We do this by blocking on the global GstPoll timer with
+ * the requested timeout. This allows us to unblock the
+ * entry by writing on the control fd.
*
- * Note that signaling the global GCond unlocks all waiting entries. So
+ * Note that writing the global GstPoll unlocks all waiting entries. So
* we need to check if an unlocked entry has changed when it unlocks.
*
* Entries that arrive too late are simply not waited on and a
* GST_CLOCK_EARLY result is returned.
*
- * should be called with LOCK held.
- *
* MT safe.
*/
static GstClockReturn
-gst_system_clock_id_wait_unlocked (GstClock * clock, GstClockEntry * entry)
+gst_system_clock_id_wait_jitter_unlocked (GstClock * clock,
+ GstClockEntry * entry, GstClockTimeDiff * jitter, gboolean restart)
{
- GstClockTime entryt, real, now, target;
+ GstSystemClock *sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+ GstClockTime entryt, now;
GstClockTimeDiff diff;
+ GstClockReturn status;
+
+ if (G_UNLIKELY (GET_ENTRY_STATUS (entry) == GST_CLOCK_UNSCHEDULED))
+ return GST_CLOCK_UNSCHEDULED;
+
+ /* need to call the overridden method because we want to sync against the time
+ * of the clock, whatever the subclass uses as a clock. */
+ now = gst_clock_get_time (clock);
- /* need to call the overridden method */
- real = GST_CLOCK_GET_CLASS (clock)->get_internal_time (clock);
+ /* get the time of the entry */
entryt = GST_CLOCK_ENTRY_TIME (entry);
- now = gst_clock_adjust_unlocked (clock, real);
- diff = entryt - now;
- target = gst_system_clock_get_internal_time (clock) + diff;
+ /* the diff of the entry with the clock is the amount of time we have to
+ * wait */
+ diff = GST_CLOCK_DIFF (now, entryt);
+ if (G_LIKELY (jitter))
+ *jitter = -diff;
GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p"
- " target %" GST_TIME_FORMAT
- " entry %" GST_TIME_FORMAT
+ " time %" GST_TIME_FORMAT
" now %" GST_TIME_FORMAT
- " real %" GST_TIME_FORMAT
- " diff %" G_GINT64_FORMAT,
- entry,
- GST_TIME_ARGS (target),
- GST_TIME_ARGS (entryt), GST_TIME_ARGS (now), GST_TIME_ARGS (real), diff);
+ " diff (time-now) %" G_GINT64_FORMAT,
+ entry, GST_TIME_ARGS (entryt), GST_TIME_ARGS (now), diff);
- if (diff > 0) {
- GTimeVal tv;
-
- GST_TIME_TO_TIMEVAL (target, tv);
+ if (G_LIKELY (diff > 0)) {
+#ifdef WAIT_DEBUGGING
+ GstClockTime final;
+#endif
while (TRUE) {
- /* now wait on the entry, it either times out or the cond is signaled. */
- if (!GST_CLOCK_TIMED_WAIT (clock, &tv)) {
- /* timeout, this is fine, we can report success now */
- GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p unlocked after timeout", entry);
- entry->status = GST_CLOCK_OK;
- break;
- } else {
- /* the waiting is interrupted because the GCond was signaled. This can
- * be because this or some other entry was unscheduled. */
- GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p unlocked with signal", entry);
- /* if the entry is unscheduled, we can stop waiting for it */
- if (entry->status == GST_CLOCK_UNSCHEDULED)
+ gint pollret;
+
+ do {
+ status = GET_ENTRY_STATUS (entry);
+
+ /* stop when we are unscheduled */
+ if (G_UNLIKELY (status == GST_CLOCK_UNSCHEDULED))
+ goto done;
+
+ /* mark the entry as busy but watch out for intermediate unscheduled
+ * statuses */
+ } while (G_UNLIKELY (!CAS_ENTRY_STATUS (entry, status, GST_CLOCK_BUSY)));
+
+ /* now wait on the entry, it either times out or the fd is written. The
+ * status of the entry is only BUSY around the poll. */
+ pollret = gst_poll_wait (sysclock->priv->timer, diff);
+
+ /* get the new status, mark as DONE. We do this so that the unschedule
+ * function knows when we left the poll and doesn't need to wakeup the
+ * poll anymore. */
+ do {
+ status = GET_ENTRY_STATUS (entry);
+ /* we were unscheduled, exit immediately */
+ if (G_UNLIKELY (status == GST_CLOCK_UNSCHEDULED))
break;
+ } while (G_UNLIKELY (!CAS_ENTRY_STATUS (entry, status, GST_CLOCK_DONE)));
+
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p unlocked, status %d, ret %d",
+ entry, status, pollret);
+
+ if (G_UNLIKELY (status == GST_CLOCK_UNSCHEDULED)) {
+ /* try to clean up The unschedule function managed to set the status to
+ * unscheduled. We now take the lock and mark the entry as unscheduled.
+ * This makes sure that the unschedule function doesn't perform a
+ * wakeup anymore. If the unschedule function has a change to perform
+ * the wakeup before us, we clean up here */
+ GST_OBJECT_LOCK (sysclock);
+ entry->unscheduled = TRUE;
+ if (entry->woken_up) {
+ gst_system_clock_remove_wakeup (sysclock);
+ }
+ GST_OBJECT_UNLOCK (sysclock);
+ goto done;
+ } else {
+ if (G_UNLIKELY (pollret != 0)) {
+ /* some other id got unlocked */
+ if (!restart) {
+ /* this can happen if the entry got unlocked because of an async
+ * entry was added to the head of the async queue. */
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "wakeup waiting for entry %p", entry);
+ goto done;
+ }
+
+ /* wait till all the entries got woken up */
+ GST_OBJECT_LOCK (sysclock);
+ gst_system_clock_wait_wakeup (sysclock);
+ GST_OBJECT_UNLOCK (sysclock);
+
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p needs to be restarted",
+ entry);
+ } else {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "entry %p unlocked after timeout",
+ entry);
+ }
+
+ /* reschedule if gst_poll_wait returned early or we have to reschedule after
+ * an unlock*/
+ now = gst_clock_get_time (clock);
+ diff = GST_CLOCK_DIFF (now, entryt);
+
+ if (diff <= 0) {
+ /* timeout, this is fine, we can report success now */
+ status = GST_CLOCK_OK;
+ SET_ENTRY_STATUS (entry, status);
+
+ GST_CAT_DEBUG (GST_CAT_CLOCK,
+ "entry %p finished, diff %" G_GINT64_FORMAT, entry, diff);
+
+#ifdef WAIT_DEBUGGING
+ final = gst_system_clock_get_internal_time (clock);
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "Waited for %" G_GINT64_FORMAT
+ " got %" G_GINT64_FORMAT " diff %" G_GINT64_FORMAT
+ " %g target-offset %" G_GINT64_FORMAT " %g", entryt, now,
+ now - entryt,
+ (double) (GstClockTimeDiff) (now - entryt) / GST_SECOND,
+ (final - target),
+ ((double) (GstClockTimeDiff) (final - target)) / GST_SECOND);
+#endif
+ goto done;
+ } else {
+ GST_CAT_DEBUG (GST_CAT_CLOCK,
+ "entry %p restart, diff %" G_GINT64_FORMAT, entry, diff);
+ }
}
}
} else {
- entry->status = GST_CLOCK_EARLY;
+ /* we are right on time or too late */
+ if (G_UNLIKELY (diff == 0))
+ status = GST_CLOCK_OK;
+ else
+ status = GST_CLOCK_EARLY;
+
+ SET_ENTRY_STATUS (entry, status);
}
- return entry->status;
+done:
+ return status;
}
static GstClockReturn
-gst_system_clock_id_wait (GstClock * clock, GstClockEntry * entry)
+gst_system_clock_id_wait_jitter (GstClock * clock, GstClockEntry * entry,
+ GstClockTimeDiff * jitter)
{
- GstClockReturn ret;
+ return gst_system_clock_id_wait_jitter_unlocked (clock, entry, jitter, TRUE);
+}
- GST_OBJECT_LOCK (clock);
- ret = gst_system_clock_id_wait_unlocked (clock, entry);
- GST_OBJECT_UNLOCK (clock);
+/* Start the async clock thread. Must be called with the object lock
+ * held */
+static gboolean
+gst_system_clock_start_async (GstSystemClock * clock)
+{
+ GError *error = NULL;
+
+ if (G_LIKELY (clock->thread != NULL))
+ return TRUE; /* Thread already running. Nothing to do */
+
+#if !GLIB_CHECK_VERSION (2, 31, 0)
+ clock->thread = g_thread_create ((GThreadFunc) gst_system_clock_async_thread,
+ clock, TRUE, &error);
+#else
+ clock->thread = g_thread_try_new ("GstSystemClock",
+ (GThreadFunc) gst_system_clock_async_thread, clock, &error);
+#endif
+
+ if (G_UNLIKELY (error))
+ goto no_thread;
+
+ /* wait for it to spin up */
+ GST_CLOCK_WAIT (clock);
+
+ return TRUE;
- return ret;
+ /* ERRORS */
+no_thread:
+ {
+ g_warning ("could not create async clock thread: %s", error->message);
+ g_error_free (error);
+ }
+ return FALSE;
}
/* Add an entry to the list of pending async waits. The entry is inserted
static GstClockReturn
gst_system_clock_id_wait_async (GstClock * clock, GstClockEntry * entry)
{
- GST_CAT_DEBUG (GST_CAT_CLOCK, "adding entry %p", entry);
+ GstSystemClock *sysclock;
+ GstClockEntry *head;
+
+ sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "adding async entry %p", entry);
GST_OBJECT_LOCK (clock);
+ /* Start the clock async thread if needed */
+ if (G_UNLIKELY (!gst_system_clock_start_async (sysclock)))
+ goto thread_error;
+
+ if (G_UNLIKELY (GET_ENTRY_STATUS (entry) == GST_CLOCK_UNSCHEDULED))
+ goto was_unscheduled;
+
+ if (clock->entries)
+ head = clock->entries->data;
+ else
+ head = NULL;
+
/* need to take a ref */
gst_clock_id_ref ((GstClockID) entry);
/* insert the entry in sorted order */
* front, else the thread is just waiting for another entry and
* will get to this entry automatically. */
if (clock->entries->data == entry) {
- GST_CAT_DEBUG (GST_CAT_CLOCK, "send signal");
- GST_CLOCK_BROADCAST (clock);
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "async entry added to head %p", head);
+ if (head == NULL) {
+ /* the list was empty before, signal the cond so that the async thread can
+ * start taking a look at the queue */
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "first entry, sending signal");
+ GST_CLOCK_BROADCAST (clock);
+ } else {
+ GstClockReturn status;
+
+ status = GET_ENTRY_STATUS (head);
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "head entry %p status %d", head, status);
+
+ if (status == GST_CLOCK_BUSY) {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "head entry is busy");
+ /* the async thread was waiting for an entry, unlock the wait so that it
+ * looks at the new head entry instead, we only need to do this once */
+ if (!sysclock->priv->async_wakeup) {
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "wakeup async thread");
+ sysclock->priv->async_wakeup = TRUE;
+ gst_system_clock_add_wakeup (sysclock);
+ }
+ }
+ }
}
GST_OBJECT_UNLOCK (clock);
return GST_CLOCK_OK;
+
+ /* ERRORS */
+thread_error:
+ {
+ /* Could not start the async clock thread */
+ GST_OBJECT_UNLOCK (clock);
+ return GST_CLOCK_ERROR;
+ }
+was_unscheduled:
+ {
+ GST_OBJECT_UNLOCK (clock);
+ return GST_CLOCK_UNSCHEDULED;
+ }
}
/* unschedule an entry. This will set the state of the entry to GST_CLOCK_UNSCHEDULED
static void
gst_system_clock_id_unschedule (GstClock * clock, GstClockEntry * entry)
{
+ GstSystemClock *sysclock;
+ GstClockReturn status;
+
+ sysclock = GST_SYSTEM_CLOCK_CAST (clock);
+
GST_CAT_DEBUG (GST_CAT_CLOCK, "unscheduling entry %p", entry);
GST_OBJECT_LOCK (clock);
- entry->status = GST_CLOCK_UNSCHEDULED;
- GST_CAT_DEBUG (GST_CAT_CLOCK, "send signal");
- GST_CLOCK_BROADCAST (clock);
+ /* change the entry status to unscheduled */
+ do {
+ status = GET_ENTRY_STATUS (entry);
+ } while (G_UNLIKELY (!CAS_ENTRY_STATUS (entry, status,
+ GST_CLOCK_UNSCHEDULED)));
+
+ if (G_LIKELY (status == GST_CLOCK_BUSY)) {
+ /* the entry was being busy, wake up all entries so that they recheck their
+ * status. We cannot wake up just one entry because allocating such a
+ * datastructure for each entry would be too heavy and unlocking an entry
+ * is usually done when shutting down or some other exceptional case. */
+ GST_CAT_DEBUG (GST_CAT_CLOCK, "entry was BUSY, doing wakeup");
+ if (!entry->unscheduled && !entry->woken_up) {
+ gst_system_clock_add_wakeup (sysclock);
+ entry->woken_up = TRUE;
+ }
+ }
GST_OBJECT_UNLOCK (clock);
}