pthread.c File Reference

Multithreading support functions. More...

#include "config.h"
#include "avcodec.h"
#include "internal.h"
#include "thread.h"
#include "libavutil/avassert.h"
#include "libavutil/common.h"
#include "libavutil/cpu.h"
#include "libavutil/internal.h"

Go to the source code of this file.

Data Structures
struct	ThreadContext
struct	PerThreadContext
	Context used by codec threads and stored in their AVCodecContext thread_opaque. More...
struct	FrameThreadContext
	Context stored in the client AVCodecContext thread_opaque. More...

Macros
#define	MAX_AUTO_THREADS   16
#define	THREAD_SAFE_CALLBACKS(avctx)   ((avctx)->thread_safe_callbacks || (!(avctx)->get_buffer && (avctx)->get_buffer2 == avcodec_default_get_buffer2))
#define	copy_fields(s, e)   memcpy(&dst->s, &src->s, (char*)&dst->e - (char*)&dst->s);

Typedefs
typedef int(	action_func )(AVCodecContext *c, void *arg)
typedef int(	action_func2 )(AVCodecContext *c, void *arg, int jobnr, int threadnr)

Functions
static void *attribute_align_arg	worker (void *v)
static av_always_inline void	avcodec_thread_park_workers (ThreadContext *c, int thread_count)
static void	thread_free (AVCodecContext *avctx)
static int	avcodec_thread_execute (AVCodecContext *avctx, action_func *func, void *arg, int *ret, int job_count, int job_size)
static int	avcodec_thread_execute2 (AVCodecContext *avctx, action_func2 *func2, void *arg, int *ret, int job_count)
static int	thread_init_internal (AVCodecContext *avctx)
static attribute_align_arg void *	frame_worker_thread (void *arg)
	Codec worker thread.
static int	update_context_from_thread (AVCodecContext *dst, AVCodecContext *src, int for_user)
	Update the next thread's AVCodecContext with values from the reference thread's context.
static int	update_context_from_user (AVCodecContext *dst, AVCodecContext *src)
	Update the next thread's AVCodecContext with values set by the user.
static void	release_delayed_buffers (PerThreadContext *p)
	Releases the buffers that this decoding thread was the last user of.
static int	submit_packet (PerThreadContext *p, AVPacket *avpkt)
int	ff_thread_decode_frame (AVCodecContext *avctx, AVFrame *picture, int *got_picture_ptr, AVPacket *avpkt)
	Submit a new frame to a decoding thread.
void	ff_thread_report_progress (ThreadFrame *f, int n, int field)
	Notify later decoding threads when part of their reference picture is ready.
void	ff_thread_await_progress (ThreadFrame *f, int n, int field)
	Wait for earlier decoding threads to finish reference pictures.
void	ff_thread_finish_setup (AVCodecContext *avctx)
	If the codec defines update_thread_context(), call this when they are ready for the next thread to start decoding the next frame.
static void	park_frame_worker_threads (FrameThreadContext *fctx, int thread_count)
	Waits for all threads to finish.
static void	frame_thread_free (AVCodecContext *avctx, int thread_count)
static int	frame_thread_init (AVCodecContext *avctx)
void	ff_thread_flush (AVCodecContext *avctx)
	Wait for decoding threads to finish and reset internal state.
int	ff_thread_can_start_frame (AVCodecContext *avctx)
static int	thread_get_buffer_internal (AVCodecContext *avctx, ThreadFrame *f, int flags)
enum AVPixelFormat	ff_thread_get_format (AVCodecContext *avctx, const enum AVPixelFormat *fmt)
	Wrapper around get_format() for frame-multithreaded codecs.
int	ff_thread_get_buffer (AVCodecContext *avctx, ThreadFrame *f, int flags)
	Wrapper around get_buffer() for frame-multithreaded codecs.
void	ff_thread_release_buffer (AVCodecContext *avctx, ThreadFrame *f)
	Wrapper around release_buffer() frame-for multithreaded codecs.
static void	validate_thread_parameters (AVCodecContext *avctx)
	Set the threading algorithms used.
int	ff_thread_init (AVCodecContext *avctx)
void	ff_thread_free (AVCodecContext *avctx)
void	ff_thread_report_progress2 (AVCodecContext *avctx, int field, int thread, int n)
void	ff_thread_await_progress2 (AVCodecContext *avctx, int field, int thread, int shift)
int	ff_alloc_entries (AVCodecContext *avctx, int count)
void	ff_reset_entries (AVCodecContext *avctx)

Detailed Description

Multithreading support functions.

See Also

doc/multithreading.txt

Definition in file pthread.c.

Macro Definition Documentation

#define MAX_AUTO_THREADS   16

Definition at line 154 of file pthread.c.

Referenced by frame_thread_init(), thread_init_internal(), and validate_thread_parameters().

#define THREAD_SAFE_CALLBACKS

(

avctx

)

((avctx)->thread_safe_callbacks || (!(avctx)->get_buffer && (avctx)->get_buffer2 == avcodec_default_get_buffer2))

Definition at line 316 of file pthread.c.

Referenced by ff_thread_can_start_frame(), frame_worker_thread(), and thread_get_buffer_internal().

#define copy_fields	(		s,
			e
	)		memcpy(&dst->s, &src->s, (char*)&dst->e - (char*)&dst->s);

Typedef Documentation

typedef int( action_func)(AVCodecContext *c, void *arg)

Definition at line 50 of file pthread.c.

typedef int( action_func2)(AVCodecContext *c, void *arg, int jobnr, int threadnr)

Definition at line 51 of file pthread.c.

Function Documentation

static void* attribute_align_arg worker ( void *  v )

static

Definition at line 156 of file pthread.c.

Referenced by thread_init_internal().

static av_always_inline void avcodec_thread_park_workers ( ThreadContext *  c, int  thread_count  )

static

Definition at line 192 of file pthread.c.

Referenced by avcodec_thread_execute(), and thread_init_internal().

static void thread_free ( AVCodecContext *  avctx )

static

Definition at line 199 of file pthread.c.

Referenced by ff_thread_free().

static int avcodec_thread_execute ( AVCodecContext *  avctx, action_func *  func, void *  arg, int *  ret, int  job_count, int  job_size  )

static

Definition at line 219 of file pthread.c.

Referenced by avcodec_thread_execute2(), and thread_init_internal().

static int avcodec_thread_execute2 ( AVCodecContext *  avctx, action_func2 *  func2, void *  arg, int *  ret, int  job_count  )

static

Definition at line 252 of file pthread.c.

Referenced by thread_init_internal().

static int thread_init_internal ( AVCodecContext *  avctx )

static

Definition at line 259 of file pthread.c.

Referenced by ff_thread_init().

static attribute_align_arg void* frame_worker_thread ( void *  arg )

static

Codec worker thread.

Automatically calls ff_thread_finish_setup() if the codec does not provide an update_thread_context method, or if the codec returns before calling it.

Definition at line 326 of file pthread.c.

Referenced by frame_thread_init().

static int update_context_from_thread ( AVCodecContext *  dst, AVCodecContext *  src, int  for_user  )

static

Update the next thread's AVCodecContext with values from the reference thread's context.

Parameters

dst	The destination context.
src	The source context.
for_user	0 if the destination is a codec thread, 1 if the destination is the user's thread

Definition at line 375 of file pthread.c.

Referenced by ff_thread_decode_frame(), ff_thread_flush(), frame_thread_free(), frame_thread_init(), and submit_packet().

static int update_context_from_user ( AVCodecContext *  dst, AVCodecContext *  src  )

static

Update the next thread's AVCodecContext with values set by the user.

Parameters

dst	The destination context.
src	The source context.

Returns

0 on success, negative error code on failure

Definition at line 434 of file pthread.c.

Referenced by ff_thread_decode_frame().

static void release_delayed_buffers ( PerThreadContext *  p )

static

Releases the buffers that this decoding thread was the last user of.

Definition at line 480 of file pthread.c.

Referenced by ff_thread_flush(), frame_thread_free(), and submit_packet().

static int submit_packet ( PerThreadContext *  p, AVPacket *  avpkt  )

static

Definition at line 500 of file pthread.c.

Referenced by ff_thread_decode_frame().

int ff_thread_decode_frame	(	AVCodecContext *	avctx,
		AVFrame *	picture,
		int *	got_picture_ptr,
		AVPacket *	avpkt
	)

Submit a new frame to a decoding thread.

Returns the next available frame in picture. *got_picture_ptr will be 0 if none is available. The return value on success is the size of the consumed packet for compatibility with avcodec_decode_video2(). This means the decoder has to consume the full packet.

Parameters are the same as avcodec_decode_video2().

Definition at line 588 of file pthread.c.

Referenced by avcodec_decode_audio4(), and avcodec_decode_video2().

void ff_thread_report_progress	(	ThreadFrame *	f,
		int	progress,
		int	field
	)

Notify later decoding threads when part of their reference picture is ready.

Call this when some part of the picture is finished decoding. Later calls with lower values of progress have no effect.

Parameters

f	The picture being decoded.
progress	Value, in arbitrary units, of how much of the picture has decoded.
field	The field being decoded, for field-picture codecs. 0 for top field or frame pictures, 1 for bottom field.

Definition at line 662 of file pthread.c.

Referenced by decode(), decode_finish_row(), decode_frame(), decode_nal_units(), decode_slice_header(), ff_hevc_hls_filters(), ff_MPV_frame_end(), ff_MPV_frame_start(), ff_MPV_report_decode_progress(), ff_rv34_decode_frame(), ff_vp8_decode_frame(), field_end(), finish_frame(), generate_missing_ref(), hevc_frame_start(), mimic_decode_frame(), rv34_decode_slice(), vp3_draw_horiz_band(), and vp8_decode_mb_row_sliced().

void ff_thread_await_progress	(	ThreadFrame *	f,
		int	progress,
		int	field
	)

Wait for earlier decoding threads to finish reference pictures.

Call this before accessing some part of a picture, with a given value for progress, and it will return after the responsible decoding thread calls ff_thread_report_progress() with the same or higher value for progress.

Parameters

f	The picture being referenced.
progress	Value, in arbitrary units, to wait for.
field	The field being referenced, for field-picture codecs. 0 for top field or frame pictures, 1 for bottom field.

Definition at line 680 of file pthread.c.

Referenced by await_reference_mb_row(), await_reference_row(), await_references(), decode(), decode_frame(), decode_slice(), ff_er_frame_end(), ff_vp8_decode_frame(), guess_mv(), hevc_await_progress(), is_intra_more_likely(), mpeg4_decode_mb(), MPV_decode_mb_internal(), rv34_decode_mv(), rv34_mc(), temporal_luma_motion_vector(), vp8_decode_mb_row_no_filter(), vp8_mc_chroma(), and vp8_mc_luma().

void ff_thread_finish_setup

(

AVCodecContext *

avctx

)

If the codec defines update_thread_context(), call this when they are ready for the next thread to start decoding the next frame.

After calling it, do not change any variables read by the update_thread_context() method, or call ff_thread_get_buffer().

Parameters

avctx

The context.

Definition at line 698 of file pthread.c.

Referenced by decode_frame(), decode_postinit(), ff_h263_decode_frame(), ff_rv34_decode_frame(), ff_vp8_decode_frame(), frame_worker_thread(), hevc_frame_start(), mimic_decode_frame(), mpeg_field_start(), tak_decode_frame(), and thread_get_buffer_internal().

static void park_frame_worker_threads ( FrameThreadContext *  fctx, int  thread_count  )

static

Waits for all threads to finish.

Definition at line 714 of file pthread.c.

Referenced by ff_thread_flush(), and frame_thread_free().

static void frame_thread_free ( AVCodecContext *  avctx, int  thread_count  )

static

Definition at line 731 of file pthread.c.

Referenced by ff_thread_free(), and frame_thread_init().

static int frame_thread_init ( AVCodecContext *  avctx )

static

Definition at line 794 of file pthread.c.

Referenced by ff_thread_init().

void ff_thread_flush

(

AVCodecContext *

avctx

)

Wait for decoding threads to finish and reset internal state.

Called by avcodec_flush_buffers().

Parameters

avctx

The context.

Definition at line 894 of file pthread.c.

Referenced by avcodec_flush_buffers().

int ff_thread_can_start_frame

(

AVCodecContext *

avctx

)

Definition at line 922 of file pthread.c.

static int thread_get_buffer_internal ( AVCodecContext *  avctx, ThreadFrame *  f, int  flags  )

static

Definition at line 932 of file pthread.c.

Referenced by ff_thread_get_buffer().

enum AVPixelFormat ff_thread_get_format	(	AVCodecContext *	avctx,
		const enum AVPixelFormat *	fmt
	)

Wrapper around get_format() for frame-multithreaded codecs.

Call this function instead of avctx->get_format(). Cannot be called after the codec has called ff_thread_finish_setup().

Parameters

avctx	The current context.
fmt	The list of available formats.

Definition at line 997 of file pthread.c.

Referenced by get_pixel_format(), and mpeg_get_pixelformat().

int ff_thread_get_buffer	(	AVCodecContext *	avctx,
		ThreadFrame *	f,
		int	flags
	)

Wrapper around get_buffer() for frame-multithreaded codecs.

Call this function instead of ff_get_buffer(f). Cannot be called after the codec has called ff_thread_finish_setup().

Parameters

avctx	The current context.
f	The frame to write into.

Definition at line 1023 of file pthread.c.

Referenced by alloc_frame(), alloc_frame_buffer(), alloc_picture(), decode_element(), decode_entropy_coded_image(), decode_frame(), dnxhd_decode_frame(), flac_decode_frame(), init_image(), jpeg2000_decode_frame(), lag_decode_frame(), libopenjpeg_decode_frame(), mimic_decode_frame(), tak_decode_frame(), tta_decode_frame(), vp8_alloc_frame(), and wavpack_decode_block().

void ff_thread_release_buffer	(	AVCodecContext *	avctx,
		ThreadFrame *	f
	)

Wrapper around release_buffer() frame-for multithreaded codecs.

Call this function instead of avctx->release_buffer(f). The AVFrame will be copied and the actual release_buffer() call will be performed later. The contents of data pointed to by the AVFrame should not be changed until ff_thread_get_buffer() is called on it.

Parameters

avctx	The current context.
f	The picture being released.

Definition at line 1031 of file pthread.c.

Referenced by decode_frame(), ff_hevc_unref_frame(), ff_mpeg_unref_picture(), ff_thread_ref_frame(), ffv1_close(), mimic_decode_end(), mimic_decode_frame(), mimic_decode_update_thread_context(), png_dec_end(), ref_frame(), unref_picture(), update_frames(), update_thread_context(), vp3_decode_flush(), vp8_alloc_frame(), and vp8_release_frame().

static void validate_thread_parameters ( AVCodecContext *  avctx )

static

Set the threading algorithms used.

Threading requires more than one thread. Frame threading requires entire frames to be passed to the codec, and introduces extra decoding delay, so is incompatible with low_delay.

Parameters

avctx

The context.

Definition at line 1090 of file pthread.c.

Referenced by ff_thread_init().

int ff_thread_init

(

AVCodecContext *

avctx

)

Definition at line 1114 of file pthread.c.

Referenced by avcodec_open2().

void ff_thread_free

(

AVCodecContext *

avctx

)

Definition at line 1130 of file pthread.c.

Referenced by avcodec_close(), and thread_init_internal().

void ff_thread_report_progress2	(	AVCodecContext *	avctx,
		int	field,
		int	thread,
		int	n
	)

Definition at line 1138 of file pthread.c.

Referenced by hls_decode_entry_wpp().

void ff_thread_await_progress2	(	AVCodecContext *	avctx,
		int	field,
		int	thread,
		int	shift
	)

Definition at line 1149 of file pthread.c.

Referenced by hls_decode_entry_wpp().

int ff_alloc_entries	(	AVCodecContext *	avctx,
		int	count
	)

Definition at line 1165 of file pthread.c.

Referenced by hls_slice_data_wpp().

void ff_reset_entries

(

AVCodecContext *

avctx

)

Definition at line 1191 of file pthread.c.

Referenced by hls_slice_data_wpp().