ffmpeg/libavcodec/thread.h
Anton Khirnov 79c47dfd25 lavc/hevcdec: unbreak WPP/progress2 code
The "progress2" API in pthread_slice.c currently associates a progress
value with a thread rather than a job, relying on the broken assumption
that a job's thread number is equal to its job number modulo thread
count.

This removes this API entirely, and changes hevcdec to use a
ThreadProgress-based implementation that associates a
mutex/cond/progress value with every job.

Fixes races and deadlocks in hevdec with slice threading, e.g. some of
those mentioned in #11221.
2024-10-15 10:37:44 +02:00

91 lines
3.2 KiB
C

/*
* Copyright (c) 2008 Alexander Strange <astrange@ithinksw.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Multithreading API for decoders
* @author Alexander Strange <astrange@ithinksw.com>
*/
#ifndef AVCODEC_THREAD_H
#define AVCODEC_THREAD_H
#include "libavutil/buffer.h"
#include "avcodec.h"
int ff_thread_can_start_frame(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().
*
* @param avctx The context.
*/
void ff_thread_finish_setup(AVCodecContext *avctx);
/**
* 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().
*
* @param avctx The current context.
* @param f The frame to write into.
*/
int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f, int flags);
int ff_slice_thread_execute_with_mainfunc(AVCodecContext *avctx,
int (*action_func2)(AVCodecContext *c, void *arg, int jobnr, int threadnr),
int (*main_func)(AVCodecContext *c), void *arg, int *ret, int job_count);
enum ThreadingStatus {
FF_THREAD_IS_COPY,
FF_THREAD_IS_FIRST_THREAD,
FF_THREAD_NO_FRAME_THREADING,
};
/**
* Allows to synchronize objects whose lifetime is the whole decoding
* process among all frame threads.
*
* When called from a non-copy thread, do nothing.
* When called from another thread, place a new RefStruct reference
* at the given offset in the calling thread's private data from
* the RefStruct reference in the private data of the first decoding thread.
* The first thread must have a valid RefStruct reference at the given
* offset in its private data; the calling thread must not have
* a reference at this offset in its private data (must be NULL).
*
* @param avctx an AVCodecContext
* @param offset offset of the RefStruct reference in avctx's private data
*
* @retval FF_THREAD_IS_COPY if frame-threading is in use and the
* calling thread is a copy; in this case, the RefStruct reference
* will be set.
* @retval FF_THREAD_IS_MAIN_THREAD if frame-threading is in use
* and the calling thread is the main thread.
* @retval FF_THREAD_NO_FRAME_THREADING if frame-threading is not in use.
*/
enum ThreadingStatus ff_thread_sync_ref(AVCodecContext *avctx, size_t offset);
#endif /* AVCODEC_THREAD_H */