/**
* SECTION:gstbufferpool
+ * @title: GstBufferPool
* @short_description: Pool for buffers
* @see_also: #GstBuffer
*
#include "gstbufferpool.h"
+#ifdef G_OS_WIN32
+# ifndef EWOULDBLOCK
+# define EWOULDBLOCK EAGAIN /* This is just to placate gcc */
+# endif
+#endif /* G_OS_WIN32 */
+
GST_DEBUG_CATEGORY_STATIC (gst_buffer_pool_debug);
#define GST_CAT_DEFAULT gst_buffer_pool_debug
gst_allocation_params_init (&priv->params);
gst_buffer_pool_config_set_allocator (priv->config, priv->allocator,
&priv->params);
- /* 1 control write for flushing */
+ /* 1 control write for flushing - the flush token */
gst_poll_write_control (priv->poll);
- /* 1 control write for marking that we are not waiting for poll */
+ /* 1 control write for marking that we are not waiting for poll - the wait token */
gst_poll_write_control (priv->poll);
GST_DEBUG_OBJECT (pool, "created");
pool = GST_BUFFER_POOL_CAST (object);
priv = pool->priv;
- GST_DEBUG_OBJECT (pool, "finalize");
+ GST_DEBUG_OBJECT (pool, "%p finalize", pool);
gst_buffer_pool_set_active (pool, FALSE);
gst_atomic_queue_unref (priv->queue);
*buffer =
gst_buffer_new_allocate (priv->allocator, priv->size, &priv->params);
+ if (!*buffer)
+ return GST_FLOW_ERROR;
+
return GST_FLOW_OK;
}
static gboolean
mark_meta_pooled (GstBuffer * buffer, GstMeta ** meta, gpointer user_data)
{
- GstBufferPool *pool = user_data;
-
- GST_DEBUG_OBJECT (pool, "marking meta %p as POOLED in buffer %p", *meta,
- buffer);
+ GST_DEBUG_OBJECT (GST_BUFFER_POOL (user_data),
+ "marking meta %p as POOLED in buffer %p", *meta, buffer);
GST_META_FLAG_SET (*meta, GST_META_FLAG_POOLED);
GST_META_FLAG_SET (*meta, GST_META_FLAG_LOCKED);
/* clear the pool */
while ((buffer = gst_atomic_queue_pop (priv->queue))) {
- gst_poll_read_control (priv->poll);
+ while (!gst_poll_read_control (priv->poll)) {
+ if (errno == EWOULDBLOCK) {
+ /* We put the buffer into the queue but did not finish writing control
+ * yet, let's wait a bit and retry */
+ g_thread_yield ();
+ continue;
+ } else {
+ /* Critical error but GstPoll already complained */
+ break;
+ }
+ }
do_free_buffer (pool, buffer);
}
return priv->cur_buffers == 0;
if (flushing) {
g_atomic_int_set (&pool->flushing, 1);
+ /* Write the flush token to wake up any waiters */
gst_poll_write_control (priv->poll);
if (pclass->flush_start)
if (pclass->flush_stop)
pclass->flush_stop (pool);
- gst_poll_read_control (priv->poll);
+ while (!gst_poll_read_control (priv->poll)) {
+ if (errno == EWOULDBLOCK) {
+ /* This should not really happen unless flushing and unflushing
+ * happens on different threads. Let's wait a bit to get back flush
+ * token from the thread that was setting it to flushing */
+ g_thread_yield ();
+ continue;
+ } else {
+ /* Critical error but GstPoll already complained */
+ break;
+ }
+ }
+
g_atomic_int_set (&pool->flushing, 0);
}
}
*
* Set the configuration of the pool. If the pool is already configured, and
* the configuration haven't change, this function will return %TRUE. If the
- * pool is active, this function will try deactivating it. Buffers allocated
- * form this pool must be returned or else this function will do nothing and
- * return FALSE.
+ * pool is active, this method will return %FALSE and active configuration
+ * will remain. Buffers allocated form this pool must be returned or else this
+ * function will do nothing and return %FALSE.
*
* @config is a #GstStructure that contains the configuration parameters for
* the pool. A default and mandatory set of parameters can be configured with
goto config_unchanged;
/* can't change the settings when active */
- if (priv->active) {
- GST_BUFFER_POOL_UNLOCK (pool);
- if (!gst_buffer_pool_set_active (pool, FALSE)) {
- GST_BUFFER_POOL_LOCK (pool);
- goto was_active;
- }
- GST_BUFFER_POOL_LOCK (pool);
-
- /* not likely but as we released the lock */
- if (priv->active)
- goto was_active;
- }
+ if (priv->active)
+ goto was_active;
/* we can't change when outstanding buffers */
if (g_atomic_int_get (&priv->outstanding) != 0)
was_active:
{
gst_structure_free (config);
- GST_WARNING_OBJECT (pool, "can't change config, we are active");
+ GST_INFO_OBJECT (pool, "can't change config, we are active");
GST_BUFFER_POOL_UNLOCK (pool);
return FALSE;
}
*
* Check if the bufferpool supports @option.
*
- * Returns: a %NULL terminated array of strings.
+ * Returns: %TRUE if the buffer pool contains @option.
*/
gboolean
gst_buffer_pool_has_option (GstBufferPool * pool, const gchar * option)
/**
* gst_buffer_pool_config_set_allocator:
* @config: a #GstBufferPool configuration
- * @allocator: a #GstAllocator
- * @params: #GstAllocationParams
+ * @allocator: (allow-none): a #GstAllocator
+ * @params: (allow-none): #GstAllocationParams
*
* Set the @allocator and @params on @config.
*
/**
* gst_buffer_pool_config_get_allocator:
* @config: (transfer none): a #GstBufferPool configuration
- * @allocator: (transfer none): a #GstAllocator
- * @params: #GstAllocationParams
+ * @allocator: (out) (allow-none) (transfer none): a #GstAllocator, or %NULL
+ * @params: (out) (allow-none): #GstAllocationParams, or %NULL
*
* Get the @allocator and @params from @config.
*
- * Returns: %TRUE, if the values are set.
+ * Returns: %TRUE, if the values are set.
*/
gboolean
gst_buffer_pool_config_get_allocator (GstStructure * config,
* Validate that changes made to @config are still valid in the context of the
* expected parameters. This function is a helper that can be used to validate
* changes made by a pool to a config when gst_buffer_pool_set_config()
- * returns %FALSE. This expects that @caps and @size haven't changed, and that
- * @min_buffers aren't lower then what we initially expected. This does not check
- * if options or allocator parameters.
+ * returns %FALSE. This expects that @caps haven't changed and that
+ * @min_buffers aren't lower then what we initially expected.
+ * This does not check if options or allocator parameters are still valid,
+ * won't check if size have changed, since changing the size is valid to adapt
+ * padding.
*
* Since: 1.4
*
gst_buffer_pool_config_get_params (config, &newcaps, &newsize, &newmin, NULL);
- if (gst_caps_is_equal (caps, newcaps) && (size == newsize)
+ if (gst_caps_is_equal (caps, newcaps) && (newsize >= size)
&& (newmin >= min_buffers))
ret = TRUE;
/* try to get a buffer from the queue */
*buffer = gst_atomic_queue_pop (priv->queue);
if (G_LIKELY (*buffer)) {
- gst_poll_read_control (priv->poll);
+ while (!gst_poll_read_control (priv->poll)) {
+ if (errno == EWOULDBLOCK) {
+ /* We put the buffer into the queue but did not finish writing control
+ * yet, let's wait a bit and retry */
+ g_thread_yield ();
+ continue;
+ } else {
+ /* Critical error but GstPoll already complained */
+ break;
+ }
+ }
result = GST_FLOW_OK;
GST_LOG_OBJECT (pool, "acquired buffer %p", *buffer);
break;
/* no buffer, try to allocate some more */
GST_LOG_OBJECT (pool, "no buffer, trying to allocate");
- result = do_alloc_buffer (pool, buffer, NULL);
+ result = do_alloc_buffer (pool, buffer, params);
if (G_LIKELY (result == GST_FLOW_OK))
/* we have a buffer, return it */
break;
/* now we release the control socket, we wait for a buffer release or
* flushing */
- gst_poll_read_control (pool->priv->poll);
- GST_LOG_OBJECT (pool, "waiting for free buffers or flushing");
- gst_poll_wait (priv->poll, GST_CLOCK_TIME_NONE);
- gst_poll_write_control (pool->priv->poll);
+ if (!gst_poll_read_control (pool->priv->poll)) {
+ if (errno == EWOULDBLOCK) {
+ /* This means that we have two threads trying to allocate buffers
+ * already, and the other one already got the wait token. This
+ * means that we only have to wait for the poll now and not write the
+ * token afterwards: we will be woken up once the other thread is
+ * woken up and that one will write the wait token it removed */
+ GST_LOG_OBJECT (pool, "waiting for free buffers or flushing");
+ gst_poll_wait (priv->poll, GST_CLOCK_TIME_NONE);
+ } else {
+ /* This is a critical error, GstPoll already gave a warning */
+ result = GST_FLOW_ERROR;
+ break;
+ }
+ } else {
+ /* We're the first thread waiting, we got the wait token and have to
+ * write it again later
+ * OR
+ * We're a second thread and just consumed the flush token and block all
+ * other threads, in which case we must not wait and give it back
+ * immediately */
+ if (!GST_BUFFER_POOL_IS_FLUSHING (pool)) {
+ GST_LOG_OBJECT (pool, "waiting for free buffers or flushing");
+ gst_poll_wait (priv->poll, GST_CLOCK_TIME_NONE);
+ }
+ gst_poll_write_control (pool->priv->poll);
+ }
}
return result;
GST_MINI_OBJECT_FLAGS (buffer));
/* memory should be untouched */
- if (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY))
- goto discard;
+ if (G_UNLIKELY (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY)))
+ goto memory_tagged;
/* size should have been reset. This is not a catch all, pool with
* size requirement per memory should do their own check. */
- if (gst_buffer_get_size (buffer) != pool->priv->size)
- goto discard;
+ if (G_UNLIKELY (gst_buffer_get_size (buffer) != pool->priv->size))
+ goto size_changed;
/* all memory should be exclusive to this buffer (and thus be writable) */
- if (!gst_buffer_is_all_memory_writable (buffer))
- goto discard;
+ if (G_UNLIKELY (!gst_buffer_is_all_memory_writable (buffer)))
+ goto not_writable;
/* keep it around in our queue */
gst_atomic_queue_push (pool->priv->queue, buffer);
return;
+memory_tagged:
+ {
+ GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pool,
+ "discarding buffer %p: memory tag set", buffer);
+ goto discard;
+ }
+size_changed:
+ {
+ GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pool,
+ "discarding buffer %p: size %" G_GSIZE_FORMAT " != %u",
+ buffer, gst_buffer_get_size (buffer), pool->priv->size);
+ goto discard;
+ }
+not_writable:
+ {
+ GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pool,
+ "discarding buffer %p: memory not writable", buffer);
+ goto discard;
+ }
discard:
{
do_free_buffer (pool, buffer);
* @pool: a #GstBufferPool
* @flushing: whether to start or stop flushing
*
- * Enabled or disable the flushing state of a @pool without freeing or
+ * Enable or disable the flushing state of a @pool without freeing or
* allocating buffers.
*
* Since: 1.4