mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-27 12:11:13 +00:00
bus: make the bus almost lockfree
Use new GstPoll functionality to wakeup the mainloop. Use an atomic queue on the writer side to post the messages. The reader side it protected with the lock still because we don't want multiple concurrent readers.
This commit is contained in:
Wim Taymans
parent
401d73df7f
commit
14d7db1b52
2 changed files with 48 additions and 99 deletions
144
gst/gstbus.c
144
gst/gstbus.c
|
|
@ -75,6 +75,7 @@
|
|||
#include <sys/types.h>
|
||||
|
||||
#include "gstinfo.h"
|
||||
#include "gstpoll.h"
|
||||
|
||||
#include "gstbus.h"
|
||||
|
||||
|
|
@ -90,8 +91,6 @@ enum
|
|||
|
||||
static void gst_bus_dispose (GObject * object);
|
||||
|
||||
static void gst_bus_set_main_context (GstBus * bus, GMainContext * ctx);
|
||||
|
||||
static GstObjectClass *parent_class = NULL;
|
||||
static guint gst_bus_signals[LAST_SIGNAL] = { 0 };
|
||||
|
||||
|
|
@ -100,7 +99,9 @@ struct _GstBusPrivate
|
|||
guint num_sync_message_emitters;
|
||||
GCond *queue_cond;
|
||||
GSource *watch_id;
|
||||
GMainContext *main_context;
|
||||
|
||||
GstPoll *poll;
|
||||
GPollFD pollfd;
|
||||
};
|
||||
|
||||
G_DEFINE_TYPE (GstBus, gst_bus, GST_TYPE_OBJECT);
|
||||
|
|
@ -184,12 +185,15 @@ gst_bus_class_init (GstBusClass * klass)
|
|||
static void
|
||||
gst_bus_init (GstBus * bus)
|
||||
{
|
||||
bus->queue = g_queue_new ();
|
||||
bus->queue = gst_atomic_queue_new (32);
|
||||
bus->queue_lock = g_mutex_new ();
|
||||
|
||||
bus->priv = G_TYPE_INSTANCE_GET_PRIVATE (bus, GST_TYPE_BUS, GstBusPrivate);
|
||||
bus->priv->queue_cond = g_cond_new ();
|
||||
|
||||
bus->priv->poll = gst_poll_new_timer ();
|
||||
gst_poll_get_read_gpollfd (bus->priv->poll, &bus->priv->pollfd);
|
||||
|
||||
GST_DEBUG_OBJECT (bus, "created");
|
||||
}
|
||||
|
||||
|
|
@ -203,63 +207,24 @@ gst_bus_dispose (GObject * object)
|
|||
|
||||
g_mutex_lock (bus->queue_lock);
|
||||
do {
|
||||
message = g_queue_pop_head (bus->queue);
|
||||
message = gst_atomic_queue_pop (bus->queue);
|
||||
if (message)
|
||||
gst_message_unref (message);
|
||||
} while (message != NULL);
|
||||
g_queue_free (bus->queue);
|
||||
gst_atomic_queue_unref (bus->queue);
|
||||
bus->queue = NULL;
|
||||
g_mutex_unlock (bus->queue_lock);
|
||||
g_mutex_free (bus->queue_lock);
|
||||
bus->queue_lock = NULL;
|
||||
g_cond_free (bus->priv->queue_cond);
|
||||
bus->priv->queue_cond = NULL;
|
||||
}
|
||||
|
||||
if (bus->priv->main_context) {
|
||||
g_main_context_unref (bus->priv->main_context);
|
||||
bus->priv->main_context = NULL;
|
||||
gst_poll_free (bus->priv->poll);
|
||||
}
|
||||
|
||||
G_OBJECT_CLASS (parent_class)->dispose (object);
|
||||
}
|
||||
|
||||
static void
|
||||
gst_bus_wakeup_main_context (GstBus * bus)
|
||||
{
|
||||
GMainContext *ctx;
|
||||
|
||||
GST_OBJECT_LOCK (bus);
|
||||
if ((ctx = bus->priv->main_context))
|
||||
g_main_context_ref (ctx);
|
||||
GST_OBJECT_UNLOCK (bus);
|
||||
|
||||
g_main_context_wakeup (ctx);
|
||||
|
||||
if (ctx)
|
||||
g_main_context_unref (ctx);
|
||||
}
|
||||
|
||||
static void
|
||||
gst_bus_set_main_context (GstBus * bus, GMainContext * ctx)
|
||||
{
|
||||
GST_OBJECT_LOCK (bus);
|
||||
|
||||
if (bus->priv->main_context != NULL) {
|
||||
g_main_context_unref (bus->priv->main_context);
|
||||
bus->priv->main_context = NULL;
|
||||
}
|
||||
|
||||
if (ctx != NULL) {
|
||||
bus->priv->main_context = g_main_context_ref (ctx);
|
||||
}
|
||||
|
||||
GST_DEBUG_OBJECT (bus, "setting main context to %p, GLib default context: %p",
|
||||
ctx, g_main_context_default ());
|
||||
|
||||
GST_OBJECT_UNLOCK (bus);
|
||||
}
|
||||
|
||||
/**
|
||||
* gst_bus_new:
|
||||
*
|
||||
|
|
@ -335,14 +300,10 @@ gst_bus_post (GstBus * bus, GstMessage * message)
|
|||
case GST_BUS_PASS:
|
||||
/* pass the message to the async queue, refcount passed in the queue */
|
||||
GST_DEBUG_OBJECT (bus, "[msg %p] pushing on async queue", message);
|
||||
g_mutex_lock (bus->queue_lock);
|
||||
g_queue_push_tail (bus->queue, message);
|
||||
g_cond_broadcast (bus->priv->queue_cond);
|
||||
g_mutex_unlock (bus->queue_lock);
|
||||
gst_atomic_queue_push (bus->queue, message);
|
||||
gst_poll_write_control (bus->priv->poll);
|
||||
GST_DEBUG_OBJECT (bus, "[msg %p] pushed on async queue", message);
|
||||
|
||||
gst_bus_wakeup_main_context (bus);
|
||||
|
||||
break;
|
||||
case GST_BUS_ASYNC:
|
||||
{
|
||||
|
|
@ -360,12 +321,9 @@ gst_bus_post (GstBus * bus, GstMessage * message)
|
|||
* queue. When the message is handled by the app and destroyed,
|
||||
* the cond will be signalled and we can continue */
|
||||
g_mutex_lock (lock);
|
||||
g_mutex_lock (bus->queue_lock);
|
||||
g_queue_push_tail (bus->queue, message);
|
||||
g_cond_broadcast (bus->priv->queue_cond);
|
||||
g_mutex_unlock (bus->queue_lock);
|
||||
|
||||
gst_bus_wakeup_main_context (bus);
|
||||
gst_atomic_queue_push (bus->queue, message);
|
||||
gst_poll_write_control (bus->priv->poll);
|
||||
|
||||
/* now block till the message is freed */
|
||||
g_cond_wait (cond, lock);
|
||||
|
|
@ -413,10 +371,8 @@ gst_bus_have_pending (GstBus * bus)
|
|||
|
||||
g_return_val_if_fail (GST_IS_BUS (bus), FALSE);
|
||||
|
||||
g_mutex_lock (bus->queue_lock);
|
||||
/* see if there is a message on the bus */
|
||||
result = !g_queue_is_empty (bus->queue);
|
||||
g_mutex_unlock (bus->queue_lock);
|
||||
result = gst_atomic_queue_length (bus->queue) != 0;
|
||||
|
||||
return result;
|
||||
}
|
||||
|
|
@ -482,7 +438,7 @@ gst_bus_timed_pop_filtered (GstBus * bus, GstClockTime timeout,
|
|||
GstMessageType types)
|
||||
{
|
||||
GstMessage *message;
|
||||
GTimeVal *timeval, abstimeout;
|
||||
GTimeVal now, then;
|
||||
gboolean first_round = TRUE;
|
||||
|
||||
g_return_val_if_fail (GST_IS_BUS (bus), NULL);
|
||||
|
|
@ -491,9 +447,13 @@ gst_bus_timed_pop_filtered (GstBus * bus, GstClockTime timeout,
|
|||
g_mutex_lock (bus->queue_lock);
|
||||
|
||||
while (TRUE) {
|
||||
GST_LOG_OBJECT (bus, "have %d messages", g_queue_get_length (bus->queue));
|
||||
gint ret;
|
||||
|
||||
while ((message = g_queue_pop_head (bus->queue))) {
|
||||
GST_LOG_OBJECT (bus, "have %d messages",
|
||||
gst_atomic_queue_length (bus->queue));
|
||||
|
||||
while ((message = gst_atomic_queue_pop (bus->queue))) {
|
||||
gst_poll_read_control (bus->priv->poll);
|
||||
GST_DEBUG_OBJECT (bus, "got message %p, %s, type mask is %u",
|
||||
message, GST_MESSAGE_TYPE_NAME (message), (guint) types);
|
||||
if ((GST_MESSAGE_TYPE (message) & types) != 0) {
|
||||
|
|
@ -510,28 +470,28 @@ gst_bus_timed_pop_filtered (GstBus * bus, GstClockTime timeout,
|
|||
if (timeout == 0)
|
||||
break;
|
||||
|
||||
if (timeout == GST_CLOCK_TIME_NONE) {
|
||||
/* wait forever */
|
||||
timeval = NULL;
|
||||
} else if (first_round) {
|
||||
glong add = timeout / 1000;
|
||||
else if (timeout != GST_CLOCK_TIME_NONE) {
|
||||
if (first_round) {
|
||||
g_get_current_time (&then);
|
||||
first_round = FALSE;
|
||||
} else {
|
||||
GstClockTime elapsed;
|
||||
|
||||
if (add == 0)
|
||||
/* no need to wait */
|
||||
break;
|
||||
g_get_current_time (&now);
|
||||
|
||||
/* make timeout absolute */
|
||||
g_get_current_time (&abstimeout);
|
||||
g_time_val_add (&abstimeout, add);
|
||||
timeval = &abstimeout;
|
||||
first_round = FALSE;
|
||||
GST_DEBUG_OBJECT (bus, "blocking for message, timeout %ld", add);
|
||||
} else {
|
||||
/* calculated the absolute end time already, no need to do it again */
|
||||
GST_DEBUG_OBJECT (bus, "blocking for message, again");
|
||||
timeval = &abstimeout; /* fool compiler */
|
||||
elapsed = GST_TIMEVAL_TO_TIME (now) - GST_TIMEVAL_TO_TIME (then);
|
||||
if (timeout > elapsed)
|
||||
timeout -= elapsed;
|
||||
else
|
||||
timeout = 0;
|
||||
}
|
||||
}
|
||||
if (!g_cond_timed_wait (bus->priv->queue_cond, bus->queue_lock, timeval)) {
|
||||
|
||||
g_mutex_unlock (bus->queue_lock);
|
||||
ret = gst_poll_wait (bus->priv->poll, timeout);
|
||||
g_mutex_lock (bus->queue_lock);
|
||||
|
||||
if (ret == 0) {
|
||||
GST_INFO_OBJECT (bus, "timed out, breaking loop");
|
||||
break;
|
||||
} else {
|
||||
|
|
@ -644,7 +604,7 @@ gst_bus_peek (GstBus * bus)
|
|||
g_return_val_if_fail (GST_IS_BUS (bus), NULL);
|
||||
|
||||
g_mutex_lock (bus->queue_lock);
|
||||
message = g_queue_peek_head (bus->queue);
|
||||
message = gst_atomic_queue_peek (bus->queue);
|
||||
if (message)
|
||||
gst_message_ref (message);
|
||||
g_mutex_unlock (bus->queue_lock);
|
||||
|
|
@ -702,24 +662,13 @@ typedef struct
|
|||
{
|
||||
GSource source;
|
||||
GstBus *bus;
|
||||
gboolean inited;
|
||||
} GstBusSource;
|
||||
|
||||
static gboolean
|
||||
gst_bus_source_prepare (GSource * source, gint * timeout)
|
||||
{
|
||||
GstBusSource *bsrc = (GstBusSource *) source;
|
||||
|
||||
/* we do this here now that we know that we're attached to a main context
|
||||
* (we don't support detaching a source from a main context and then
|
||||
* re-attaching it to a different main context) */
|
||||
if (G_UNLIKELY (!bsrc->inited)) {
|
||||
gst_bus_set_main_context (bsrc->bus, g_source_get_context (source));
|
||||
bsrc->inited = TRUE;
|
||||
}
|
||||
|
||||
*timeout = -1;
|
||||
return gst_bus_have_pending (bsrc->bus);
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
static gboolean
|
||||
|
|
@ -727,7 +676,7 @@ gst_bus_source_check (GSource * source)
|
|||
{
|
||||
GstBusSource *bsrc = (GstBusSource *) source;
|
||||
|
||||
return gst_bus_have_pending (bsrc->bus);
|
||||
return bsrc->bus->priv->pollfd.revents & (G_IO_IN | G_IO_HUP | G_IO_ERR);
|
||||
}
|
||||
|
||||
static gboolean
|
||||
|
|
@ -789,7 +738,6 @@ gst_bus_source_finalize (GSource * source)
|
|||
bus->priv->watch_id = NULL;
|
||||
GST_OBJECT_UNLOCK (bus);
|
||||
|
||||
gst_bus_set_main_context (bsource->bus, NULL);
|
||||
gst_object_unref (bsource->bus);
|
||||
bsource->bus = NULL;
|
||||
}
|
||||
|
|
@ -821,7 +769,7 @@ gst_bus_create_watch (GstBus * bus)
|
|||
source = (GstBusSource *) g_source_new (&gst_bus_source_funcs,
|
||||
sizeof (GstBusSource));
|
||||
source->bus = gst_object_ref (bus);
|
||||
source->inited = FALSE;
|
||||
g_source_add_poll ((GSource *) source, &bus->priv->pollfd);
|
||||
|
||||
return (GSource *) source;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -28,6 +28,7 @@ typedef struct _GstBusClass GstBusClass;
|
|||
|
||||
#include <gst/gstmessage.h>
|
||||
#include <gst/gstclock.h>
|
||||
#include <gst/gstatomicqueue.h>
|
||||
|
||||
G_BEGIN_DECLS
|
||||
|
||||
|
|
@ -115,7 +116,7 @@ struct _GstBus
|
|||
GstObject object;
|
||||
|
||||
/*< private >*/
|
||||
GQueue *queue;
|
||||
GstAtomicQueue *queue;
|
||||
GMutex *queue_lock;
|
||||
|
||||
GstBusSyncHandler sync_handler;
|
||||
|
|
|
|||
Loading…
Reference in a new issue