vpx/vp8/decoder/onyxd_int.h
Peter Boström d42e876164 Add atomics to vp8 synchronization primitives.
Fixes issue on iPad Pro 10.5 (and probably other places) where threads
are not properly synchronized. On x86 this data race was benign as load
and store instructions are atomic, they were being atomic in practice as
the program hasn't been observed to be miscompiled.

Such guarantees are not made outside x86, and real problems manifested
where libvpx reliably reproduced a broken bitstream for even just the
initial keyframe. This was detected in WebRTC where this device started
using multithreading (as its CPU count is higher than earlier devices,
where the problem did not manifest as single-threading was used in
practice).

This issue was not detected under thread-sanitizer bots as mutexes were
conditionally used under this platform to simulate the protected read
and write semantics that were in practice provided on x86 platforms.

This change also removes several mutexes, so encoder/decoder state is
lighter-weight after this change and we do not need to initialize so
many mutexes (this was done even on non-thread-sanitizer platforms where
they were unused).

Change-Id: If41fcb0d99944f7bbc8ec40877cdc34d672ae72a
2017-08-31 17:55:57 -07:00

152 lines
4.2 KiB
C

/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef VP8_DECODER_ONYXD_INT_H_
#define VP8_DECODER_ONYXD_INT_H_
#include "vpx_config.h"
#include "vp8/common/onyxd.h"
#include "treereader.h"
#include "vp8/common/onyxc_int.h"
#include "vp8/common/threading.h"
#if CONFIG_ERROR_CONCEALMENT
#include "ec_types.h"
#endif
#ifdef __cplusplus
extern "C" {
#endif
typedef struct {
int ithread;
void *ptr1;
void *ptr2;
} DECODETHREAD_DATA;
typedef struct { MACROBLOCKD mbd; } MB_ROW_DEC;
typedef struct {
int enabled;
unsigned int count;
const unsigned char *ptrs[MAX_PARTITIONS];
unsigned int sizes[MAX_PARTITIONS];
} FRAGMENT_DATA;
#define MAX_FB_MT_DEC 32
struct frame_buffers {
/*
* this struct will be populated with frame buffer management
* info in future commits. */
/* decoder instances */
struct VP8D_COMP *pbi[MAX_FB_MT_DEC];
};
typedef struct VP8D_COMP {
DECLARE_ALIGNED(16, MACROBLOCKD, mb);
YV12_BUFFER_CONFIG *dec_fb_ref[NUM_YV12_BUFFERS];
DECLARE_ALIGNED(16, VP8_COMMON, common);
/* the last partition will be used for the modes/mvs */
vp8_reader mbc[MAX_PARTITIONS];
VP8D_CONFIG oxcf;
FRAGMENT_DATA fragments;
#if CONFIG_MULTITHREAD
/* variable for threading */
vpx_atomic_int b_multithreaded_rd;
int max_threads;
int current_mb_col_main;
unsigned int decoding_thread_count;
int allocated_decoding_thread_count;
int mt_baseline_filter_level[MAX_MB_SEGMENTS];
int sync_range;
/* Each row remembers its already decoded column. */
vpx_atomic_int *mt_current_mb_col;
unsigned char **mt_yabove_row; /* mb_rows x width */
unsigned char **mt_uabove_row;
unsigned char **mt_vabove_row;
unsigned char **mt_yleft_col; /* mb_rows x 16 */
unsigned char **mt_uleft_col; /* mb_rows x 8 */
unsigned char **mt_vleft_col; /* mb_rows x 8 */
MB_ROW_DEC *mb_row_di;
DECODETHREAD_DATA *de_thread_data;
pthread_t *h_decoding_thread;
sem_t *h_event_start_decoding;
sem_t h_event_end_decoding;
/* end of threading data */
#endif
int64_t last_time_stamp;
int ready_for_new_data;
vp8_prob prob_intra;
vp8_prob prob_last;
vp8_prob prob_gf;
vp8_prob prob_skip_false;
#if CONFIG_ERROR_CONCEALMENT
MB_OVERLAP *overlaps;
/* the mb num from which modes and mvs (first partition) are corrupt */
unsigned int mvs_corrupt_from_mb;
#endif
int ec_enabled;
int ec_active;
int decoded_key_frame;
int independent_partitions;
int frame_corrupt_residual;
vpx_decrypt_cb decrypt_cb;
void *decrypt_state;
} VP8D_COMP;
void vp8cx_init_de_quantizer(VP8D_COMP *pbi);
void vp8_mb_init_dequantizer(VP8D_COMP *pbi, MACROBLOCKD *xd);
int vp8_decode_frame(VP8D_COMP *cpi);
int vp8_create_decoder_instances(struct frame_buffers *fb, VP8D_CONFIG *oxcf);
int vp8_remove_decoder_instances(struct frame_buffers *fb);
#if CONFIG_DEBUG
#define CHECK_MEM_ERROR(lval, expr) \
do { \
lval = (expr); \
if (!lval) \
vpx_internal_error(&pbi->common.error, VPX_CODEC_MEM_ERROR, \
"Failed to allocate " #lval " at %s:%d", __FILE__, \
__LINE__); \
} while (0)
#else
#define CHECK_MEM_ERROR(lval, expr) \
do { \
lval = (expr); \
if (!lval) \
vpx_internal_error(&pbi->common.error, VPX_CODEC_MEM_ERROR, \
"Failed to allocate " #lval); \
} while (0)
#endif
#ifdef __cplusplus
} // extern "C"
#endif
#endif // VP8_DECODER_ONYXD_INT_H_