[FFmpeg-devel] [PATCH 2/3] avcodec/pthread_slice: use slice threading from avutil
Muhammad Faiz
mfcc64 at gmail.com
Wed Jul 12 03:44:11 EEST 2017
Also remove pthread_cond_broadcast(progress_cond) on uninit.
Broadcasting it is not required because workers are always
parked when they are not in thread_execute. So it is imposible
that a worker is waiting on progress_cond when uninitialized.
Benchmark:
./ffmpeg -threads $threads -thread_type slice -i 10slices.mp4 -f null null
threads=2:
old: 70.212s 70.525s 70.877s
new: 65.219s 65.377s 65.484s
threads=3:
old: 65.086s 66.306s 66.409s
new: 63.229s 65.026s 65.116s
threads=4:
old: 60.993s 61.482s 62.123s
new: 59.224s 59.441s 59.667s
threads=5:
old: 57.576s 57.860s 58.832s
new: 53.032s 53.948s 54.086s
Signed-off-by: Muhammad Faiz <mfcc64 at gmail.com>
---
libavcodec/pthread_slice.c | 122 ++++++++-------------------------------------
1 file changed, 20 insertions(+), 102 deletions(-)
diff --git a/libavcodec/pthread_slice.c b/libavcodec/pthread_slice.c
index 60f5b78..c781d35 100644
--- a/libavcodec/pthread_slice.c
+++ b/libavcodec/pthread_slice.c
@@ -34,26 +34,19 @@
#include "libavutil/cpu.h"
#include "libavutil/mem.h"
#include "libavutil/thread.h"
+#include "libavutil/slicethread.h"
typedef int (action_func)(AVCodecContext *c, void *arg);
typedef int (action_func2)(AVCodecContext *c, void *arg, int jobnr, int threadnr);
typedef struct SliceThreadContext {
- pthread_t *workers;
+ AVSliceThread *thread;
action_func *func;
action_func2 *func2;
void *args;
int *rets;
- int job_count;
int job_size;
- pthread_cond_t last_job_cond;
- pthread_cond_t current_job_cond;
- pthread_mutex_t current_job_lock;
- unsigned current_execute;
- int current_job;
- int done;
-
int *entries;
int entries_count;
int thread_count;
@@ -61,43 +54,16 @@ typedef struct SliceThreadContext {
pthread_mutex_t *progress_mutex;
} SliceThreadContext;
-static void* attribute_align_arg worker(void *v)
+static void worker_func(void *priv, int jobnr, int threadnr, int nb_jobs, int nb_threads)
{
- AVCodecContext *avctx = v;
+ AVCodecContext *avctx = priv;
SliceThreadContext *c = avctx->internal->thread_ctx;
- unsigned last_execute = 0;
- int our_job = c->job_count;
- int thread_count = avctx->thread_count;
- int self_id;
-
- pthread_mutex_lock(&c->current_job_lock);
- self_id = c->current_job++;
- for (;;){
- int ret;
- while (our_job >= c->job_count) {
- if (c->current_job == thread_count + c->job_count)
- pthread_cond_signal(&c->last_job_cond);
-
- while (last_execute == c->current_execute && !c->done)
- pthread_cond_wait(&c->current_job_cond, &c->current_job_lock);
- last_execute = c->current_execute;
- our_job = self_id;
-
- if (c->done) {
- pthread_mutex_unlock(&c->current_job_lock);
- return NULL;
- }
- }
- pthread_mutex_unlock(&c->current_job_lock);
+ int ret;
- ret = c->func ? c->func(avctx, (char*)c->args + our_job*c->job_size):
- c->func2(avctx, c->args, our_job, self_id);
- if (c->rets)
- c->rets[our_job%c->job_count] = ret;
-
- pthread_mutex_lock(&c->current_job_lock);
- our_job = c->current_job++;
- }
+ ret = c->func ? c->func(avctx, (char *)c->args + c->job_size * jobnr)
+ : c->func2(avctx, c->args, jobnr, threadnr);
+ if (c->rets)
+ c->rets[jobnr] = ret;
}
void ff_slice_thread_free(AVCodecContext *avctx)
@@ -105,40 +71,19 @@ void ff_slice_thread_free(AVCodecContext *avctx)
SliceThreadContext *c = avctx->internal->thread_ctx;
int i;
- pthread_mutex_lock(&c->current_job_lock);
- c->done = 1;
- pthread_cond_broadcast(&c->current_job_cond);
- for (i = 0; i < c->thread_count; i++)
- pthread_cond_broadcast(&c->progress_cond[i]);
- pthread_mutex_unlock(&c->current_job_lock);
-
- for (i=0; i<avctx->thread_count; i++)
- pthread_join(c->workers[i], NULL);
+ avpriv_slicethread_free(&c->thread);
for (i = 0; i < c->thread_count; i++) {
pthread_mutex_destroy(&c->progress_mutex[i]);
pthread_cond_destroy(&c->progress_cond[i]);
}
- pthread_mutex_destroy(&c->current_job_lock);
- pthread_cond_destroy(&c->current_job_cond);
- pthread_cond_destroy(&c->last_job_cond);
-
av_freep(&c->entries);
av_freep(&c->progress_mutex);
av_freep(&c->progress_cond);
-
- av_freep(&c->workers);
av_freep(&avctx->internal->thread_ctx);
}
-static av_always_inline void thread_park_workers(SliceThreadContext *c, int thread_count)
-{
- while (c->current_job != thread_count + c->job_count)
- pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);
- pthread_mutex_unlock(&c->current_job_lock);
-}
-
static int thread_execute(AVCodecContext *avctx, action_func* func, void *arg, int *ret, int job_count, int job_size)
{
SliceThreadContext *c = avctx->internal->thread_ctx;
@@ -149,19 +94,12 @@ static int thread_execute(AVCodecContext *avctx, action_func* func, void *arg, i
if (job_count <= 0)
return 0;
- pthread_mutex_lock(&c->current_job_lock);
-
- c->current_job = avctx->thread_count;
- c->job_count = job_count;
c->job_size = job_size;
c->args = arg;
c->func = func;
c->rets = ret;
- c->current_execute++;
- pthread_cond_broadcast(&c->current_job_cond);
-
- thread_park_workers(c, avctx->thread_count);
+ avpriv_slicethread_execute(c->thread, job_count, 0);
return 0;
}
@@ -174,7 +112,6 @@ static int thread_execute2(AVCodecContext *avctx, action_func2* func2, void *arg
int ff_slice_thread_init(AVCodecContext *avctx)
{
- int i;
SliceThreadContext *c;
int thread_count = avctx->thread_count;
@@ -204,35 +141,16 @@ int ff_slice_thread_init(AVCodecContext *avctx)
return 0;
}
- c = av_mallocz(sizeof(SliceThreadContext));
- if (!c)
- return -1;
-
- c->workers = av_mallocz_array(thread_count, sizeof(pthread_t));
- if (!c->workers) {
- av_free(c);
- return -1;
- }
-
- avctx->internal->thread_ctx = c;
- c->current_job = 0;
- c->job_count = 0;
- c->job_size = 0;
- c->done = 0;
- pthread_cond_init(&c->current_job_cond, NULL);
- pthread_cond_init(&c->last_job_cond, NULL);
- pthread_mutex_init(&c->current_job_lock, NULL);
- pthread_mutex_lock(&c->current_job_lock);
- for (i=0; i<thread_count; i++) {
- if(pthread_create(&c->workers[i], NULL, worker, avctx)) {
- avctx->thread_count = i;
- pthread_mutex_unlock(&c->current_job_lock);
- ff_thread_free(avctx);
- return -1;
- }
+ avctx->internal->thread_ctx = c = av_mallocz(sizeof(*c));
+ if (!c || (thread_count = avpriv_slicethread_create(&c->thread, avctx, worker_func, NULL, thread_count)) <= 1) {
+ if (c)
+ avpriv_slicethread_free(&c->thread);
+ av_freep(&avctx->internal->thread_ctx);
+ avctx->thread_count = 1;
+ avctx->active_thread_type = 0;
+ return 0;
}
-
- thread_park_workers(c, thread_count);
+ avctx->thread_count = thread_count;
avctx->execute = thread_execute;
avctx->execute2 = thread_execute2;
--
2.9.3
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