[FFmpeg-devel] [PATCH] avcodec/qsv: polling free synchronization

[Dmitry Rogozhkin]

From: Andrey Orlov <andrey.orlov at intel.com>

synchronization by sync point after DEVICE_BUSY

Fixes: CPU usage on AVC decode cases (18% -> 9%)
---
 libavcodec/qsv.c          | 17 +++++++++++++++++
 libavcodec/qsv_internal.h |  2 ++
 libavcodec/qsvdec.c       | 12 ++++++++----
 libavcodec/qsvdec.h       |  2 ++
 libavcodec/qsvenc.c       | 13 +++++++++----
 libavcodec/qsvenc.h       |  2 ++
 6 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/libavcodec/qsv.c b/libavcodec/qsv.c
index b00e427..4b5018b 100644
--- a/libavcodec/qsv.c
+++ b/libavcodec/qsv.c
@@ -32,6 +32,7 @@
 #include "libavutil/hwcontext_qsv.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/avassert.h"
+#include "libavutil/time.h"
 
 #include "avcodec.h"
 #include "qsv_internal.h"
@@ -852,3 +853,19 @@ int ff_qsv_close_internal_session(QSVSession *qs)
 #endif
     return 0;
 }
+
+void ff_qsv_handle_device_busy(mfxSession *session, mfxSyncPoint *sync, mfxStatus *ret, unsigned sleep)
+{
+    int sync_ret;
+
+    if (*sync) {
+        sync_ret = MFXVideoCORE_SyncOperation(*session, *sync, MFX_INFINITE);
+        if (sync_ret == MFX_ERR_NONE) {
+            *sync = NULL;
+        } else {
+            *ret = MFX_ERR_ABORTED;
+        }
+    } else {
+        av_usleep(sleep);
+    }
+}
diff --git a/libavcodec/qsv_internal.h b/libavcodec/qsv_internal.h
index 3755927..01c98cc 100644
--- a/libavcodec/qsv_internal.h
+++ b/libavcodec/qsv_internal.h
@@ -141,4 +141,6 @@ int ff_qsv_init_session_frames(AVCodecContext *avctx, mfxSession *session,
 
 int ff_qsv_find_surface_idx(QSVFramesContext *ctx, QSVFrame *frame);
 
+void ff_qsv_handle_device_busy(mfxSession *session, mfxSyncPoint *sync, mfxStatus *ret, unsigned sleep);
+
 #endif /* AVCODEC_QSV_INTERNAL_H */
diff --git a/libavcodec/qsvdec.c b/libavcodec/qsvdec.c
index ae50239..aa83272 100644
--- a/libavcodec/qsvdec.c
+++ b/libavcodec/qsvdec.c
@@ -457,8 +457,12 @@ static int qsv_decode(AVCodecContext *avctx, QSVContext *q,
 
         ret = MFXVideoDECODE_DecodeFrameAsync(q->session, avpkt->size ? &bs : NULL,
                                               insurf, &outsurf, sync);
+
+        if (ret == MFX_ERR_NONE)
+            q->last_dec_sync = *sync;
+
         if (ret == MFX_WRN_DEVICE_BUSY)
-            av_usleep(500);
+            ff_qsv_handle_device_busy(&q->session, &q->last_dec_sync, &ret, 500);
 
     } while (ret == MFX_WRN_DEVICE_BUSY || ret == MFX_ERR_MORE_SURFACE);
 
@@ -510,9 +514,9 @@ static int qsv_decode(AVCodecContext *avctx, QSVContext *q,
         out_frame->queued = 0;
 
         if (avctx->pix_fmt != AV_PIX_FMT_QSV) {
-            do {
-                ret = MFXVideoCORE_SyncOperation(q->session, *sync, 1000);
-            } while (ret == MFX_WRN_IN_EXECUTION);
+            ret = MFXVideoCORE_SyncOperation(q->session, *sync, MFX_INFINITE);
+            if (ret < 0)
+                return ret;
         }
 
         av_freep(&sync);
diff --git a/libavcodec/qsvdec.h b/libavcodec/qsvdec.h
index dec1f61..d27ea68 100644
--- a/libavcodec/qsvdec.h
+++ b/libavcodec/qsvdec.h
@@ -72,6 +72,8 @@ typedef struct QSVContext {
 
     mfxExtBuffer **ext_buffers;
     int         nb_ext_buffers;
+
+    mfxSyncPoint last_dec_sync;
 } QSVContext;
 
 extern const AVCodecHWConfigInternal *ff_qsv_hw_configs[];
diff --git a/libavcodec/qsvenc.c b/libavcodec/qsvenc.c
index ba85d64..bd5dd75 100644
--- a/libavcodec/qsvenc.c
+++ b/libavcodec/qsvenc.c
@@ -1368,8 +1368,13 @@ static int encode_frame(AVCodecContext *avctx, QSVEncContext *q,
 
     do {
         ret = MFXVideoENCODE_EncodeFrameAsync(q->session, enc_ctrl, surf, bs, sync);
+
+        if (ret == MFX_ERR_NONE)
+            q->last_enc_sync = *sync;
+
         if (ret == MFX_WRN_DEVICE_BUSY)
-            av_usleep(500);
+            ff_qsv_handle_device_busy(&q->session, &q->last_enc_sync, &ret, 500);
+
     } while (ret == MFX_WRN_DEVICE_BUSY || ret == MFX_WRN_IN_EXECUTION);
 
     if (ret > 0)
@@ -1435,9 +1440,9 @@ int ff_qsv_encode(AVCodecContext *avctx, QSVEncContext *q,
         av_fifo_generic_read(q->async_fifo, &sync,    sizeof(sync),    NULL);
         av_fifo_generic_read(q->async_fifo, &bs,      sizeof(bs),      NULL);
 
-        do {
-            ret = MFXVideoCORE_SyncOperation(q->session, *sync, 1000);
-        } while (ret == MFX_WRN_IN_EXECUTION);
+        ret = MFXVideoCORE_SyncOperation(q->session, *sync, MFX_INFINITE);
+        if (ret < 0)
+            return ret;
 
         new_pkt.dts  = av_rescale_q(bs->DecodeTimeStamp, (AVRational){1, 90000}, avctx->time_base);
         new_pkt.pts  = av_rescale_q(bs->TimeStamp,       (AVRational){1, 90000}, avctx->time_base);
diff --git a/libavcodec/qsvenc.h b/libavcodec/qsvenc.h
index ec8b541..f1c22d7 100644
--- a/libavcodec/qsvenc.h
+++ b/libavcodec/qsvenc.h
@@ -185,6 +185,8 @@ typedef struct QSVEncContext {
     char *load_plugins;
     SetEncodeCtrlCB *set_encode_ctrl_cb;
     int forced_idr;
+
+    mfxSyncPoint last_enc_sync;
 } QSVEncContext;
 
 int ff_qsv_enc_init(AVCodecContext *avctx, QSVEncContext *q);
-- 
1.8.3.1