ref: 03191f738ebffc41495f2a2d0585bb77104e10dc
parent: ab5704f02ce471b3dd792dee2872d452b3537d30
parent: d42e876164c63eead9d0db6f53cda866f508cd4a
author: Peter Boström <pbos@chromium.org>
date: Thu Aug 31 21:36:22 EDT 2017
Merge "Add atomics to vp8 synchronization primitives."
--- a/vp8/common/threading.h
+++ b/vp8/common/threading.h
@@ -191,47 +191,18 @@
#define x86_pause_hint()
#endif
-#if defined(__has_feature)
-#if __has_feature(thread_sanitizer)
-#define USE_MUTEX_LOCK 1
-#endif
-#endif
-
#include "vpx_util/vpx_thread.h"
+#include "vpx_util/vpx_atomics.h"
-static INLINE int protected_read(pthread_mutex_t *const mutex, const int *p) {- (void)mutex;
-#if defined(USE_MUTEX_LOCK)
- int ret;
- pthread_mutex_lock(mutex);
- ret = *p;
- pthread_mutex_unlock(mutex);
- return ret;
-#endif
- return *p;
-}
-
-static INLINE void sync_read(pthread_mutex_t *const mutex, int mb_col,
- const int *last_row_current_mb_col,
- const int nsync) {- while (mb_col > (protected_read(mutex, last_row_current_mb_col) - nsync)) {+static INLINE void vp8_atomic_spin_wait(
+ int mb_col, const vpx_atomic_int *last_row_current_mb_col,
+ const int nsync) {+ while (mb_col > (vpx_atomic_load_acquire(last_row_current_mb_col) - nsync)) {x86_pause_hint();
thread_sleep(0);
}
}
-static INLINE void protected_write(pthread_mutex_t *mutex, int *p, int v) {- (void)mutex;
-#if defined(USE_MUTEX_LOCK)
- pthread_mutex_lock(mutex);
- *p = v;
- pthread_mutex_unlock(mutex);
- return;
-#endif
- *p = v;
-}
-
-#undef USE_MUTEX_LOCK
#endif /* CONFIG_OS_SUPPORT && CONFIG_MULTITHREAD */
#ifdef __cplusplus
--- a/vp8/decoder/decodeframe.c
+++ b/vp8/decoder/decodeframe.c
@@ -1205,7 +1205,8 @@
pbi->frame_corrupt_residual = 0;
#if CONFIG_MULTITHREAD
- if (pbi->b_multithreaded_rd && pc->multi_token_partition != ONE_PARTITION) {+ if (vpx_atomic_load_acquire(&pbi->b_multithreaded_rd) &&
+ pc->multi_token_partition != ONE_PARTITION) {unsigned int thread;
vp8mt_decode_mb_rows(pbi, xd);
vp8_yv12_extend_frame_borders(yv12_fb_new);
--- a/vp8/decoder/onyxd_int.h
+++ b/vp8/decoder/onyxd_int.h
@@ -68,7 +68,7 @@
#if CONFIG_MULTITHREAD
/* variable for threading */
- int b_multithreaded_rd;
+ vpx_atomic_int b_multithreaded_rd;
int max_threads;
int current_mb_col_main;
unsigned int decoding_thread_count;
@@ -76,9 +76,8 @@
int mt_baseline_filter_level[MAX_MB_SEGMENTS];
int sync_range;
- int *mt_current_mb_col; /* Each row remembers its already decoded column. */
- pthread_mutex_t *pmutex;
- pthread_mutex_t mt_mutex; /* mutex for b_multithreaded_rd */
+ /* 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;
--- a/vp8/decoder/threading.c
+++ b/vp8/decoder/threading.c
@@ -79,7 +79,8 @@
if (pc->full_pixel) mbd->fullpixel_mask = 0xfffffff8;
}
- for (i = 0; i < pc->mb_rows; ++i) pbi->mt_current_mb_col[i] = -1;
+ for (i = 0; i < pc->mb_rows; ++i)
+ vpx_atomic_store_release(&pbi->mt_current_mb_col[i], -1);
}
static void mt_decode_macroblock(VP8D_COMP *pbi, MACROBLOCKD *xd,
@@ -247,12 +248,13 @@
static void mt_decode_mb_rows(VP8D_COMP *pbi, MACROBLOCKD *xd,
int start_mb_row) {- const int *last_row_current_mb_col;
- int *current_mb_col;
+ const vpx_atomic_int *last_row_current_mb_col;
+ vpx_atomic_int *current_mb_col;
int mb_row;
VP8_COMMON *pc = &pbi->common;
const int nsync = pbi->sync_range;
- const int first_row_no_sync_above = pc->mb_cols + nsync;
+ const vpx_atomic_int first_row_no_sync_above =
+ VPX_ATOMIC_INIT(pc->mb_cols + nsync);
int num_part = 1 << pbi->common.multi_token_partition;
int last_mb_row = start_mb_row;
@@ -356,13 +358,11 @@
for (mb_col = 0; mb_col < pc->mb_cols; ++mb_col) { if (((mb_col - 1) % nsync) == 0) {- pthread_mutex_t *mutex = &pbi->pmutex[mb_row];
- protected_write(mutex, current_mb_col, mb_col - 1);
+ vpx_atomic_store_release(current_mb_col, mb_col - 1);
}
if (mb_row && !(mb_col & (nsync - 1))) {- pthread_mutex_t *mutex = &pbi->pmutex[mb_row - 1];
- sync_read(mutex, mb_col, last_row_current_mb_col, nsync);
+ vp8_atomic_spin_wait(mb_col, last_row_current_mb_col, nsync);
}
/* Distance of MB to the various image edges.
@@ -548,7 +548,7 @@
}
/* last MB of row is ready just after extension is done */
- protected_write(&pbi->pmutex[mb_row], current_mb_col, mb_col + nsync);
+ vpx_atomic_store_release(current_mb_col, mb_col + nsync);
++xd->mode_info_context; /* skip prediction column */
xd->up_available = 1;
@@ -568,10 +568,10 @@
ENTROPY_CONTEXT_PLANES mb_row_left_context;
while (1) {- if (protected_read(&pbi->mt_mutex, &pbi->b_multithreaded_rd) == 0) break;
+ if (vpx_atomic_load_acquire(&pbi->b_multithreaded_rd) == 0) break;
if (sem_wait(&pbi->h_event_start_decoding[ithread]) == 0) {- if (protected_read(&pbi->mt_mutex, &pbi->b_multithreaded_rd) == 0) {+ if (vpx_atomic_load_acquire(&pbi->b_multithreaded_rd) == 0) {break;
} else {MACROBLOCKD *xd = &mbrd->mbd;
@@ -589,9 +589,8 @@
int core_count = 0;
unsigned int ithread;
- pbi->b_multithreaded_rd = 0;
+ vpx_atomic_init(&pbi->b_multithreaded_rd, 0);
pbi->allocated_decoding_thread_count = 0;
- pthread_mutex_init(&pbi->mt_mutex, NULL);
/* limit decoding threads to the max number of token partitions */
core_count = (pbi->max_threads > 8) ? 8 : pbi->max_threads;
@@ -602,7 +601,7 @@
}
if (core_count > 1) {- pbi->b_multithreaded_rd = 1;
+ vpx_atomic_init(&pbi->b_multithreaded_rd, 1);
pbi->decoding_thread_count = core_count - 1;
CALLOC_ARRAY(pbi->h_decoding_thread, pbi->decoding_thread_count);
@@ -648,16 +647,6 @@
void vp8mt_de_alloc_temp_buffers(VP8D_COMP *pbi, int mb_rows) {int i;
- /* De-allocate mutex */
- if (pbi->pmutex != NULL) {- for (i = 0; i < mb_rows; ++i) {- pthread_mutex_destroy(&pbi->pmutex[i]);
- }
-
- vpx_free(pbi->pmutex);
- pbi->pmutex = NULL;
- }
-
vpx_free(pbi->mt_current_mb_col);
pbi->mt_current_mb_col = NULL;
@@ -723,7 +712,7 @@
int i;
int uv_width;
- if (protected_read(&pbi->mt_mutex, &pbi->b_multithreaded_rd)) {+ if (vpx_atomic_load_acquire(&pbi->b_multithreaded_rd)) {vp8mt_de_alloc_temp_buffers(pbi, prev_mb_rows);
/* our internal buffers are always multiples of 16 */
@@ -741,18 +730,12 @@
uv_width = width >> 1;
- /* Allocate mutex */
- CHECK_MEM_ERROR(pbi->pmutex,
- vpx_malloc(sizeof(*pbi->pmutex) * pc->mb_rows));
- if (pbi->pmutex) {- for (i = 0; i < pc->mb_rows; ++i) {- pthread_mutex_init(&pbi->pmutex[i], NULL);
- }
- }
+ /* Allocate a vpx_atomic_int for each mb row. */
+ CHECK_MEM_ERROR(pbi->mt_current_mb_col,
+ vpx_malloc(sizeof(*pbi->mt_current_mb_col) * pc->mb_rows));
+ for (i = 0; i < pc->mb_rows; ++i)
+ vpx_atomic_init(&pbi->mt_current_mb_col[i], 0);
- /* Allocate an int for each mb row. */
- CALLOC_ARRAY(pbi->mt_current_mb_col, pc->mb_rows);
-
/* Allocate memory for above_row buffers. */
CALLOC_ARRAY(pbi->mt_yabove_row, pc->mb_rows);
for (i = 0; i < pc->mb_rows; ++i)
@@ -792,9 +775,9 @@
void vp8_decoder_remove_threads(VP8D_COMP *pbi) {/* shutdown MB Decoding thread; */
- if (protected_read(&pbi->mt_mutex, &pbi->b_multithreaded_rd)) {+ if (vpx_atomic_load_acquire(&pbi->b_multithreaded_rd)) {int i;
- protected_write(&pbi->mt_mutex, &pbi->b_multithreaded_rd, 0);
+ vpx_atomic_store_release(&pbi->b_multithreaded_rd, 0);
/* allow all threads to exit */
for (i = 0; i < pbi->allocated_decoding_thread_count; ++i) {@@ -824,7 +807,6 @@
vp8mt_de_alloc_temp_buffers(pbi, pbi->common.mb_rows);
}
- pthread_mutex_destroy(&pbi->mt_mutex);
}
void vp8mt_decode_mb_rows(VP8D_COMP *pbi, MACROBLOCKD *xd) {--- a/vp8/encoder/bitstream.c
+++ b/vp8/encoder/bitstream.c
@@ -1416,7 +1416,7 @@
vp8_start_encode(&cpi->bc[1], cx_data, cx_data_end);
#if CONFIG_MULTITHREAD
- if (cpi->b_multi_threaded) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded)) {pack_mb_row_tokens(cpi, &cpi->bc[1]);
} else {vp8_pack_tokens(&cpi->bc[1], cpi->tok, cpi->tok_count);
--- a/vp8/encoder/encodeframe.c
+++ b/vp8/encoder/encodeframe.c
@@ -341,11 +341,11 @@
#if CONFIG_MULTITHREAD
const int nsync = cpi->mt_sync_range;
- const int rightmost_col = cm->mb_cols + nsync;
- const int *last_row_current_mb_col;
- int *current_mb_col = &cpi->mt_current_mb_col[mb_row];
+ vpx_atomic_int rightmost_col = VPX_ATOMIC_INIT(cm->mb_cols + nsync);
+ const vpx_atomic_int *last_row_current_mb_col;
+ vpx_atomic_int *current_mb_col = &cpi->mt_current_mb_col[mb_row];
- if ((cpi->b_multi_threaded != 0) && (mb_row != 0)) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) != 0 && mb_row != 0) {last_row_current_mb_col = &cpi->mt_current_mb_col[mb_row - 1];
} else {last_row_current_mb_col = &rightmost_col;
@@ -415,15 +415,13 @@
vp8_copy_mem16x16(x->src.y_buffer, x->src.y_stride, x->thismb, 16);
#if CONFIG_MULTITHREAD
- if (cpi->b_multi_threaded != 0) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) != 0) { if (((mb_col - 1) % nsync) == 0) {- pthread_mutex_t *mutex = &cpi->pmutex[mb_row];
- protected_write(mutex, current_mb_col, mb_col - 1);
+ vpx_atomic_store_release(current_mb_col, mb_col - 1);
}
if (mb_row && !(mb_col & (nsync - 1))) {- pthread_mutex_t *mutex = &cpi->pmutex[mb_row - 1];
- sync_read(mutex, mb_col, last_row_current_mb_col, nsync);
+ vp8_atomic_spin_wait(mb_col, last_row_current_mb_col, nsync);
}
}
#endif
@@ -563,8 +561,9 @@
xd->dst.u_buffer + 8, xd->dst.v_buffer + 8);
#if CONFIG_MULTITHREAD
- if (cpi->b_multi_threaded != 0) {- protected_write(&cpi->pmutex[mb_row], current_mb_col, rightmost_col);
+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) != 0) {+ vpx_atomic_store_release(current_mb_col,
+ vpx_atomic_load_acquire(&rightmost_col));
}
#endif
@@ -749,13 +748,14 @@
vpx_usec_timer_start(&emr_timer);
#if CONFIG_MULTITHREAD
- if (cpi->b_multi_threaded) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded)) {int i;
vp8cx_init_mbrthread_data(cpi, x, cpi->mb_row_ei,
cpi->encoding_thread_count);
- for (i = 0; i < cm->mb_rows; ++i) cpi->mt_current_mb_col[i] = -1;
+ for (i = 0; i < cm->mb_rows; ++i)
+ vpx_atomic_store_release(&cpi->mt_current_mb_col[i], -1);
for (i = 0; i < cpi->encoding_thread_count; ++i) {sem_post(&cpi->h_event_start_encoding[i]);
--- a/vp8/encoder/ethreading.c
+++ b/vp8/encoder/ethreading.c
@@ -26,11 +26,11 @@
VP8_COMMON *cm = &cpi->common;
while (1) {- if (protected_read(&cpi->mt_mutex, &cpi->b_multi_threaded) == 0) break;
+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) == 0) break;
if (sem_wait(&cpi->h_event_start_lpf) == 0) {/* we're shutting down */
- if (protected_read(&cpi->mt_mutex, &cpi->b_multi_threaded) == 0) break;
+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) == 0) break;
vp8_loopfilter_frame(cpi, cm);
@@ -48,7 +48,7 @@
ENTROPY_CONTEXT_PLANES mb_row_left_context;
while (1) {- if (protected_read(&cpi->mt_mutex, &cpi->b_multi_threaded) == 0) break;
+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) == 0) break;
if (sem_wait(&cpi->h_event_start_encoding[ithread]) == 0) {const int nsync = cpi->mt_sync_range;
@@ -66,7 +66,7 @@
int *totalrate = &mbri->totalrate;
/* we're shutting down */
- if (protected_read(&cpi->mt_mutex, &cpi->b_multi_threaded) == 0) break;
+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) == 0) break;
xd->mode_info_context = cm->mi + cm->mode_info_stride * (ithread + 1);
xd->mode_info_stride = cm->mode_info_stride;
@@ -80,8 +80,8 @@
int recon_y_stride = cm->yv12_fb[ref_fb_idx].y_stride;
int recon_uv_stride = cm->yv12_fb[ref_fb_idx].uv_stride;
int map_index = (mb_row * cm->mb_cols);
- const int *last_row_current_mb_col;
- int *current_mb_col = &cpi->mt_current_mb_col[mb_row];
+ const vpx_atomic_int *last_row_current_mb_col;
+ vpx_atomic_int *current_mb_col = &cpi->mt_current_mb_col[mb_row];
#if (CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING)
vp8_writer *w = &cpi->bc[1 + (mb_row % num_part)];
@@ -108,13 +108,11 @@
/* for each macroblock col in image */
for (mb_col = 0; mb_col < cm->mb_cols; ++mb_col) { if (((mb_col - 1) % nsync) == 0) {- pthread_mutex_t *mutex = &cpi->pmutex[mb_row];
- protected_write(mutex, current_mb_col, mb_col - 1);
+ vpx_atomic_store_release(current_mb_col, mb_col - 1);
}
if (mb_row && !(mb_col & (nsync - 1))) {- pthread_mutex_t *mutex = &cpi->pmutex[mb_row - 1];
- sync_read(mutex, mb_col, last_row_current_mb_col, nsync);
+ vp8_atomic_spin_wait(mb_col, last_row_current_mb_col, nsync);
}
#if CONFIG_REALTIME_ONLY & CONFIG_ONTHEFLY_BITPACKING
@@ -286,7 +284,7 @@
vp8_extend_mb_row(&cm->yv12_fb[dst_fb_idx], xd->dst.y_buffer + 16,
xd->dst.u_buffer + 8, xd->dst.v_buffer + 8);
- protected_write(&cpi->pmutex[mb_row], current_mb_col, mb_col + nsync);
+ vpx_atomic_store_release(current_mb_col, mb_col + nsync);
/* this is to account for the border */
xd->mode_info_context++;
@@ -490,12 +488,10 @@
int vp8cx_create_encoder_threads(VP8_COMP *cpi) {const VP8_COMMON *cm = &cpi->common;
- cpi->b_multi_threaded = 0;
+ vpx_atomic_init(&cpi->b_multi_threaded, 0);
cpi->encoding_thread_count = 0;
cpi->b_lpf_running = 0;
- pthread_mutex_init(&cpi->mt_mutex, NULL);
-
if (cm->processor_core_count > 1 && cpi->oxcf.multi_threaded > 1) {int ithread;
int th_count = cpi->oxcf.multi_threaded - 1;
@@ -526,7 +522,7 @@
CHECK_MEM_ERROR(cpi->en_thread_data,
vpx_malloc(sizeof(ENCODETHREAD_DATA) * th_count));
- cpi->b_multi_threaded = 1;
+ vpx_atomic_store_release(&cpi->b_multi_threaded, 1);
cpi->encoding_thread_count = th_count;
/*
@@ -555,7 +551,7 @@
if (rc) {/* shutdown other threads */
- protected_write(&cpi->mt_mutex, &cpi->b_multi_threaded, 0);
+ vpx_atomic_store_release(&cpi->b_multi_threaded, 0);
for (--ithread; ithread >= 0; ithread--) {pthread_join(cpi->h_encoding_thread[ithread], 0);
sem_destroy(&cpi->h_event_start_encoding[ithread]);
@@ -569,8 +565,6 @@
vpx_free(cpi->mb_row_ei);
vpx_free(cpi->en_thread_data);
- pthread_mutex_destroy(&cpi->mt_mutex);
-
return -1;
}
@@ -585,7 +579,7 @@
if (rc) {/* shutdown other threads */
- protected_write(&cpi->mt_mutex, &cpi->b_multi_threaded, 0);
+ vpx_atomic_store_release(&cpi->b_multi_threaded, 0);
for (--ithread; ithread >= 0; ithread--) {sem_post(&cpi->h_event_start_encoding[ithread]);
sem_post(&cpi->h_event_end_encoding[ithread]);
@@ -603,8 +597,6 @@
vpx_free(cpi->mb_row_ei);
vpx_free(cpi->en_thread_data);
- pthread_mutex_destroy(&cpi->mt_mutex);
-
return -2;
}
}
@@ -613,9 +605,9 @@
}
void vp8cx_remove_encoder_threads(VP8_COMP *cpi) {- if (protected_read(&cpi->mt_mutex, &cpi->b_multi_threaded)) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded)) {/* shutdown other threads */
- protected_write(&cpi->mt_mutex, &cpi->b_multi_threaded, 0);
+ vpx_atomic_store_release(&cpi->b_multi_threaded, 0);
{int i;
@@ -643,6 +635,5 @@
vpx_free(cpi->mb_row_ei);
vpx_free(cpi->en_thread_data);
}
- pthread_mutex_destroy(&cpi->mt_mutex);
}
#endif
--- a/vp8/encoder/onyx_if.c
+++ b/vp8/encoder/onyx_if.c
@@ -451,18 +451,6 @@
cpi->mb.pip = 0;
#if CONFIG_MULTITHREAD
- /* De-allocate mutex */
- if (cpi->pmutex != NULL) {- VP8_COMMON *const pc = &cpi->common;
- int i;
-
- for (i = 0; i < pc->mb_rows; ++i) {- pthread_mutex_destroy(&cpi->pmutex[i]);
- }
- vpx_free(cpi->pmutex);
- cpi->pmutex = NULL;
- }
-
vpx_free(cpi->mt_current_mb_col);
cpi->mt_current_mb_col = NULL;
#endif
@@ -1153,9 +1141,6 @@
int width = cm->Width;
int height = cm->Height;
-#if CONFIG_MULTITHREAD
- int prev_mb_rows = cm->mb_rows;
-#endif
if (vp8_alloc_frame_buffers(cm, width, height)) {vpx_internal_error(&cpi->common.error, VPX_CODEC_MEM_ERROR,
@@ -1247,26 +1232,11 @@
if (cpi->oxcf.multi_threaded > 1) {int i;
- /* De-allocate and re-allocate mutex */
- if (cpi->pmutex != NULL) {- for (i = 0; i < prev_mb_rows; ++i) {- pthread_mutex_destroy(&cpi->pmutex[i]);
- }
- vpx_free(cpi->pmutex);
- cpi->pmutex = NULL;
- }
-
- CHECK_MEM_ERROR(cpi->pmutex,
- vpx_malloc(sizeof(*cpi->pmutex) * cm->mb_rows));
- if (cpi->pmutex) {- for (i = 0; i < cm->mb_rows; ++i) {- pthread_mutex_init(&cpi->pmutex[i], NULL);
- }
- }
-
vpx_free(cpi->mt_current_mb_col);
CHECK_MEM_ERROR(cpi->mt_current_mb_col,
vpx_malloc(sizeof(*cpi->mt_current_mb_col) * cm->mb_rows));
+ for (i = 0; i < cm->mb_rows; ++i)
+ vpx_atomic_init(&cpi->mt_current_mb_col[i], 0);
}
#endif
@@ -3274,7 +3244,7 @@
}
#if CONFIG_MULTITHREAD
- if (cpi->b_multi_threaded) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded)) {sem_post(&cpi->h_event_end_lpf); /* signal that we have set filter_level */
}
#endif
@@ -4471,7 +4441,7 @@
#endif
#if CONFIG_MULTITHREAD
- if (cpi->b_multi_threaded) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded)) {/* start loopfilter in separate thread */
sem_post(&cpi->h_event_start_lpf);
cpi->b_lpf_running = 1;
@@ -4497,7 +4467,8 @@
#if CONFIG_MULTITHREAD
/* wait that filter_level is picked so that we can continue with stream
* packing */
- if (cpi->b_multi_threaded) sem_wait(&cpi->h_event_end_lpf);
+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded))
+ sem_wait(&cpi->h_event_end_lpf);
#endif
/* build the bitstream */
@@ -5341,7 +5312,7 @@
#if CONFIG_MULTITHREAD
/* wait for the lpf thread done */
- if (cpi->b_multi_threaded && cpi->b_lpf_running) {+ if (vpx_atomic_load_acquire(&cpi->b_multi_threaded) && cpi->b_lpf_running) {sem_wait(&cpi->h_event_end_lpf);
cpi->b_lpf_running = 0;
}
--- a/vp8/encoder/onyx_int.h
+++ b/vp8/encoder/onyx_int.h
@@ -518,11 +518,9 @@
#if CONFIG_MULTITHREAD
/* multithread data */
- pthread_mutex_t *pmutex;
- pthread_mutex_t mt_mutex; /* mutex for b_multi_threaded */
- int *mt_current_mb_col;
+ vpx_atomic_int *mt_current_mb_col;
int mt_sync_range;
- int b_multi_threaded;
+ vpx_atomic_int b_multi_threaded;
int encoding_thread_count;
int b_lpf_running;
--- a/vp8/vp8_dx_iface.c
+++ b/vp8/vp8_dx_iface.c
@@ -415,7 +415,7 @@
#endif
#if CONFIG_MULTITHREAD
- if (pbi->b_multithreaded_rd) {+ if (vpx_atomic_load_acquire(&pbi->b_multithreaded_rd)) {vp8mt_alloc_temp_buffers(pbi, pc->Width, prev_mb_rows);
}
#else
--- /dev/null
+++ b/vpx_util/vpx_atomics.h
@@ -1,0 +1,133 @@
+/*
+ * Copyright (c) 2017 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 VPX_UTIL_VPX_ATOMICS_H_
+#define VPX_UTIL_VPX_ATOMICS_H_
+
+#include "./vpx_config.h"
+
+#ifdef __cplusplus
+extern "C" {+#endif // __cplusplus
+
+#if CONFIG_OS_SUPPORT && CONFIG_MULTITHREAD
+
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
+ (defined(__cplusplus) && __cplusplus >= 201112L)
+// Where available, use <stdatomic.h>
+#include <stdatomic.h>
+#define VPX_USE_STD_ATOMIC
+#else
+// Look for built-ins.
+#if !defined(__has_builtin)
+#define __has_builtin(x) 0 // Compatibility with non-clang compilers.
+#endif // !defined(__has_builtin)
+
+#if (__has_builtin(__atomic_load_n)) || \
+ (defined(__GNUC__) && \
+ (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 7)))
+// For GCC >= 4.7 and Clang that support __atomic builtins, use those.
+#define VPX_USE_ATOMIC_BUILTINS
+#else
+// Use platform-specific asm barriers.
+#if defined(_MSC_VER)
+// TODO(pbos): This assumes that newer versions of MSVC are building with the
+// default /volatile:ms (or older, where this is always true. Consider adding
+// support for using <atomic> instead of stdatomic.h when building C++11 under
+// MSVC. It's unclear what to do for plain C under /volatile:iso (inline asm?),
+// there're no explicit Interlocked* functions for only storing or loading
+// (presumably because volatile has historically implied that on MSVC).
+//
+// For earlier versions of MSVC or the default /volatile:ms volatile int are
+// acquire/release and require no barrier.
+#define vpx_atomic_memory_barrier() \
+ do { \+ } while (0)
+#else
+#if ARCH_X86 || ARCH_X86_64
+// Use a compiler barrier on x86, no runtime penalty.
+#define vpx_atomic_memory_barrier() __asm__ __volatile__("" ::: "memory")+#elif ARCH_ARM
+#define vpx_atomic_memory_barrier() __asm__ __volatile__("dmb ish" ::: "memory")+#elif ARCH_MIPS
+#define vpx_atomic_memory_barrier() __asm__ __volatile__("sync" ::: "memory")+#else
+#error Unsupported architecture!
+#endif // ARCH_X86 || ARCH_X86_64
+#endif // defined(_MSC_VER)
+#endif // atomic builtin availability check
+#endif // stdatomic availability check
+
+// These are wrapped in a struct so that they are not easily accessed directly
+// on any platform (to discourage programmer errors by setting values directly).
+// This primitive MUST be initialized using vpx_atomic_init or VPX_ATOMIC_INIT
+// (NOT memset) and accessed through vpx_atomic_ functions.
+typedef struct vpx_atomic_int {+#if defined(VPX_USE_STD_ATOMIC)
+ atomic_int value;
+#else
+ volatile int value;
+#endif // defined(USE_STD_ATOMIC)
+} vpx_atomic_int;
+
+#if defined(VPX_USE_STD_ATOMIC)
+#define VPX_ATOMIC_INIT(num) \
+ { ATOMIC_VAR_INIT(num) }+#else
+#define VPX_ATOMIC_INIT(num) \
+ { num }+#endif // defined(VPX_USE_STD_ATOMIC)
+
+// Initialization of an atomic int, not thread safe.
+static INLINE void vpx_atomic_init(vpx_atomic_int *atomic, int value) {+#if defined(VPX_USE_STD_ATOMIC)
+ atomic_init(&atomic->value, value);
+#else
+ atomic->value = value;
+#endif // defined(USE_STD_ATOMIC)
+}
+
+static INLINE void vpx_atomic_store_release(vpx_atomic_int *atomic, int value) {+#if defined(VPX_USE_STD_ATOMIC)
+ atomic_store_explicit(&atomic->value, value, memory_order_release);
+#elif defined(VPX_USE_ATOMIC_BUILTINS)
+ __atomic_store_n(&atomic->value, value, __ATOMIC_RELEASE);
+#else
+ vpx_atomic_memory_barrier();
+ atomic->value = value;
+#endif // defined(VPX_USE_STD_ATOMIC)
+}
+
+static INLINE int vpx_atomic_load_acquire(const vpx_atomic_int *atomic) {+#if defined(VPX_USE_STD_ATOMIC)
+ // const_cast (in C) that doesn't trigger -Wcast-qual.
+ return atomic_load_explicit(
+ (atomic_int *)(uintptr_t)(const void *)&atomic->value,
+ memory_order_acquire);
+#elif defined(VPX_USE_ATOMIC_BUILTINS)
+ return __atomic_load_n(&atomic->value, __ATOMIC_ACQUIRE);
+#else
+ int v = atomic->value;
+ vpx_atomic_memory_barrier();
+ return v;
+#endif // defined(VPX_USE_STD_ATOMIC)
+}
+
+#undef VPX_USE_STD_ATOMIC
+#undef VPX_USE_ATOMIC_BUILTINS
+#undef vpx_atomic_memory_barrier
+
+#endif /* CONFIG_OS_SUPPORT && CONFIG_MULTITHREAD */
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus
+
+#endif // VPX_UTIL_VPX_ATOMICS_H_
--- a/vpx_util/vpx_util.mk
+++ b/vpx_util/vpx_util.mk
@@ -8,6 +8,7 @@
## be found in the AUTHORS file in the root of the source tree.
##
+UTIL_SRCS-yes += vpx_atomics.h
UTIL_SRCS-yes += vpx_util.mk
UTIL_SRCS-yes += vpx_thread.c
UTIL_SRCS-yes += vpx_thread.h