gstreamer/sys/v4l2codecs/gstv4l2codecallocator.c
Nicolas Dufresne f992c521c3 v4l2codecs: allocator: Keep dmabuf mapped
DMABuf allocator already implements DMABuf Sync, meaning that doing
mmap/munmap (unless the mode have changed) is not required. In fact, on
systems with IOMMU it makes the kernel redo the mmu table which is visible
in the CPU usage.

This change reduces CPU usage when decoding
bbb_sunflower_2160p_60fps_normal.mp4 on RK3399 SoC from over 30% to
around 15%.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2152>
2021-04-08 15:22:49 -04:00

377 lines
9.3 KiB
C

/* GStreamer
* Copyright (C) 2020 Collabora Ltd.
* Author: Nicolas Dufresne <nicolas.dufresne@collabora.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "gstv4l2codecallocator.h"
#include <gst/video/video.h>
#include <sys/types.h>
#define GST_CAT_DEFAULT allocator_debug
GST_DEBUG_CATEGORY_STATIC (allocator_debug);
typedef struct _GstV4l2CodecBuffer GstV4l2CodecBuffer;
struct _GstV4l2CodecBuffer
{
gint index;
GstMemory *mem[GST_VIDEO_MAX_PLANES];
guint num_mems;
guint outstanding_mems;
};
struct _GstV4l2CodecAllocator
{
GstDmaBufAllocator parent;
GQueue pool;
gint pool_size;
gboolean detached;
GCond buffer_cond;
gboolean flushing;
GstV4l2Decoder *decoder;
GstPadDirection direction;
};
G_DEFINE_TYPE_WITH_CODE (GstV4l2CodecAllocator, gst_v4l2_codec_allocator,
GST_TYPE_DMABUF_ALLOCATOR,
GST_DEBUG_CATEGORY_INIT (allocator_debug, "v4l2codecs-allocator", 0,
"V4L2 Codecs Allocator"));
static gboolean gst_v4l2_codec_allocator_release (GstMiniObject * mini_object);
static GQuark
gst_v4l2_codec_buffer_quark (void)
{
static gsize buffer_quark = 0;
if (g_once_init_enter (&buffer_quark)) {
GQuark quark = g_quark_from_string ("GstV4l2CodecBuffer");
g_once_init_leave (&buffer_quark, quark);
}
return buffer_quark;
}
static GstV4l2CodecBuffer *
gst_v4l2_codec_buffer_new (GstAllocator * allocator, GstV4l2Decoder * decoder,
GstPadDirection direction, gint index)
{
GstV4l2CodecBuffer *buf;
guint i, num_mems;
gint fds[GST_VIDEO_MAX_PLANES];
gsize sizes[GST_VIDEO_MAX_PLANES];
gsize offsets[GST_VIDEO_MAX_PLANES];
if (!gst_v4l2_decoder_export_buffer (decoder, direction, index, fds, sizes,
offsets, &num_mems))
return NULL;
buf = g_new0 (GstV4l2CodecBuffer, 1);
buf->index = index;
buf->num_mems = num_mems;
for (i = 0; i < buf->num_mems; i++) {
GstMemory *mem = gst_fd_allocator_alloc (allocator, fds[i], sizes[i],
GST_FD_MEMORY_FLAG_KEEP_MAPPED);
gst_memory_resize (mem, offsets[i], sizes[i] - offsets[i]);
GST_MINI_OBJECT (mem)->dispose = gst_v4l2_codec_allocator_release;
gst_mini_object_set_qdata (GST_MINI_OBJECT (mem),
gst_v4l2_codec_buffer_quark (), buf, NULL);
/* On outstanding memory keeps a reference on the allocator, this is
* needed to break the cycle. */
gst_object_unref (mem->allocator);
buf->mem[i] = mem;
}
GST_DEBUG_OBJECT (allocator, "Create buffer %i with %i memory fds",
buf->index, buf->num_mems);
return buf;
}
static void
gst_v4l2_codec_buffer_free (GstV4l2CodecBuffer * buf)
{
guint i;
g_warn_if_fail (buf->outstanding_mems == 0);
GST_DEBUG_OBJECT (buf->mem[0]->allocator, "Freeing buffer %i", buf->index);
for (i = 0; i < buf->num_mems; i++) {
GstMemory *mem = buf->mem[i];
GST_MINI_OBJECT (mem)->dispose = NULL;
g_object_ref (mem->allocator);
gst_memory_unref (mem);
}
g_free (buf);
}
static void
gst_v4l2_codec_buffer_acquire (GstV4l2CodecBuffer * buf)
{
buf->outstanding_mems += buf->num_mems;
}
static gboolean
gst_v4l2_codec_buffer_release_mem (GstV4l2CodecBuffer * buf)
{
return (--buf->outstanding_mems == 0);
}
static gboolean
gst_v4l2_codec_allocator_release (GstMiniObject * mini_object)
{
GstMemory *mem = GST_MEMORY_CAST (mini_object);
GstV4l2CodecAllocator *self = GST_V4L2_CODEC_ALLOCATOR (mem->allocator);
GstV4l2CodecBuffer *buf;
GST_OBJECT_LOCK (self);
buf = gst_mini_object_get_qdata (mini_object, gst_v4l2_codec_buffer_quark ());
gst_memory_ref (mem);
if (gst_v4l2_codec_buffer_release_mem (buf)) {
GST_DEBUG_OBJECT (self, "Placing back buffer %i into pool", buf->index);
g_queue_push_tail (&self->pool, buf);
g_cond_signal (&self->buffer_cond);
}
GST_OBJECT_UNLOCK (self);
/* Keep last in case we are holding on the last allocator ref */
g_object_unref (mem->allocator);
/* Returns FALSE so that our mini object isn't freed */
return FALSE;
}
static gboolean
gst_v4l2_codec_allocator_prepare (GstV4l2CodecAllocator * self)
{
GstV4l2Decoder *decoder = self->decoder;
GstPadDirection direction = self->direction;
gint ret;
guint i;
ret = gst_v4l2_decoder_request_buffers (decoder, direction, self->pool_size);
if (ret < self->pool_size) {
if (ret >= 0)
GST_ERROR_OBJECT (self,
"%i buffer was needed, but only %i could be allocated",
self->pool_size, ret);
goto failed;
}
for (i = 0; i < self->pool_size; i++) {
GstV4l2CodecBuffer *buf = gst_v4l2_codec_buffer_new (GST_ALLOCATOR (self),
decoder, direction, i);
g_queue_push_tail (&self->pool, buf);
}
return TRUE;
failed:
gst_v4l2_decoder_request_buffers (decoder, direction, 0);
return FALSE;
}
static void
gst_v4l2_codec_allocator_init (GstV4l2CodecAllocator * self)
{
g_cond_init (&self->buffer_cond);
}
static void
gst_v4l2_codec_allocator_dispose (GObject * object)
{
GstV4l2CodecAllocator *self = GST_V4L2_CODEC_ALLOCATOR (object);
GstV4l2CodecBuffer *buf;
while ((buf = g_queue_pop_head (&self->pool)))
gst_v4l2_codec_buffer_free (buf);
gst_clear_object (&self->decoder);
G_OBJECT_CLASS (gst_v4l2_codec_allocator_parent_class)->dispose (object);
}
static void
gst_v4l2_codec_allocator_finalize (GObject * object)
{
GstV4l2CodecAllocator *self = GST_V4L2_CODEC_ALLOCATOR (object);
if (!self->detached)
gst_v4l2_decoder_request_buffers (self->decoder, self->direction, 0);
g_cond_clear (&self->buffer_cond);
G_OBJECT_CLASS (gst_v4l2_codec_allocator_parent_class)->finalize (object);
}
static void
gst_v4l2_codec_allocator_class_init (GstV4l2CodecAllocatorClass * klass)
{
GstAllocatorClass *allocator_class = GST_ALLOCATOR_CLASS (klass);
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->dispose = gst_v4l2_codec_allocator_dispose;
object_class->finalize = gst_v4l2_codec_allocator_finalize;
allocator_class->alloc = NULL;
}
GstV4l2CodecAllocator *
gst_v4l2_codec_allocator_new (GstV4l2Decoder * decoder,
GstPadDirection direction, guint num_buffers)
{
GstV4l2CodecAllocator *self =
g_object_new (GST_TYPE_V4L2_CODEC_ALLOCATOR, NULL);
self->decoder = g_object_ref (decoder);
self->direction = direction;
self->pool_size = num_buffers;
if (!gst_v4l2_codec_allocator_prepare (self)) {
g_object_unref (self);
return NULL;
}
return self;
}
GstMemory *
gst_v4l2_codec_allocator_alloc (GstV4l2CodecAllocator * self)
{
GstV4l2CodecBuffer *buf;
GstMemory *mem = NULL;
GST_OBJECT_LOCK (self);
buf = g_queue_pop_head (&self->pool);
if (buf) {
GST_DEBUG_OBJECT (self, "Allocated buffer %i", buf->index);
g_warn_if_fail (buf->num_mems == 1);
mem = buf->mem[0];
g_object_ref (mem->allocator);
buf->outstanding_mems++;
}
GST_OBJECT_UNLOCK (self);
return mem;
}
gboolean
gst_v4l2_codec_allocator_create_buffer (GstV4l2CodecAllocator * self)
{
/* TODO implement */
return FALSE;
}
gboolean
gst_v4l2_codec_allocator_wait_for_buffer (GstV4l2CodecAllocator * self)
{
gboolean ret;
GST_OBJECT_LOCK (self);
while (self->pool.length == 0 && !self->flushing)
g_cond_wait (&self->buffer_cond, GST_OBJECT_GET_LOCK (self));
ret = !self->flushing;
GST_OBJECT_UNLOCK (self);
return ret;
}
gboolean
gst_v4l2_codec_allocator_prepare_buffer (GstV4l2CodecAllocator * self,
GstBuffer * gstbuf)
{
GstV4l2CodecBuffer *buf;
guint i;
GST_OBJECT_LOCK (self);
buf = g_queue_pop_head (&self->pool);
if (!buf) {
GST_OBJECT_UNLOCK (self);
return FALSE;
}
GST_DEBUG_OBJECT (self, "Allocated buffer %i", buf->index);
gst_v4l2_codec_buffer_acquire (buf);
for (i = 0; i < buf->num_mems; i++) {
gst_buffer_append_memory (gstbuf, buf->mem[i]);
g_object_ref (buf->mem[i]->allocator);
}
GST_OBJECT_UNLOCK (self);
return TRUE;
}
guint
gst_v4l2_codec_allocator_get_pool_size (GstV4l2CodecAllocator * self)
{
guint size;
GST_OBJECT_LOCK (self);
size = self->pool_size;
GST_OBJECT_UNLOCK (self);
return size;
}
void
gst_v4l2_codec_allocator_detach (GstV4l2CodecAllocator * self)
{
GST_OBJECT_LOCK (self);
if (!self->detached) {
self->detached = TRUE;
gst_v4l2_decoder_request_buffers (self->decoder, self->direction, 0);
}
GST_OBJECT_UNLOCK (self);
}
void
gst_v4l2_codec_allocator_set_flushing (GstV4l2CodecAllocator * self,
gboolean flushing)
{
GST_OBJECT_LOCK (self);
self->flushing = flushing;
if (flushing)
g_cond_broadcast (&self->buffer_cond);
GST_OBJECT_UNLOCK (self);
}
guint32
gst_v4l2_codec_memory_get_index (GstMemory * mem)
{
GstV4l2CodecBuffer *buf;
buf = gst_mini_object_get_qdata (GST_MINI_OBJECT (mem),
gst_v4l2_codec_buffer_quark ());
g_return_val_if_fail (buf, G_MAXUINT32);
return buf->index;
}