[FFmpeg-devel] [PATCH 1/3] nvenc: use runtime api version to support old drivers

Timo Rothenpieler timo at rothenpieler.org
Wed Jul 15 18:15:54 EEST 2020


On 15.07.2020 16:34, wangbin wrote:
> From: wang-bin <wbsecg1 at gmail.com>
> 
> There are reserved bit fields in nvEncoderAPI.h structs, so driver's abi
> is stable. Requesting runtime version of these structs should work. I've
> compared 7.0~9.x headers, and confirmed on some devices.
> ---
>   libavcodec/nvenc.c | 72 ++++++++++++++++++++++++++--------------------
>   libavcodec/nvenc.h |  3 ++
>   2 files changed, 44 insertions(+), 31 deletions(-)
> 
> diff --git a/libavcodec/nvenc.c b/libavcodec/nvenc.c
> index c6740c1842..ac35cb9f48 100644
> --- a/libavcodec/nvenc.c
> +++ b/libavcodec/nvenc.c
> @@ -193,14 +193,26 @@ static void nvenc_print_driver_requirement(AVCodecContext *avctx, int level)
>       av_log(avctx, level, "The minimum required Nvidia driver for nvenc is %s or newer\n", minver);
>   }
>   
> +static inline uint32_t struct_ver_rt(NvencContext* ctx, uint32_t struct_ver)
> +{
> +    return ((uint32_t)ctx->apiver_rt | ((struct_ver)<<16) | (0x7 << 28));
> +}

I'm really not a fan of hard-coding magic numbers, that can change in 
the future, into the ffmpeg implementation.

> +static inline uint32_t api_ver(uint32_t major_ver, uint32_t minor_ver)
> +{
> +    return major_ver | (minor_ver << 24);
> +}
> +
>   static av_cold int nvenc_load_libraries(AVCodecContext *avctx)
>   {
>       NvencContext *ctx            = avctx->priv_data;
>       NvencDynLoadFunctions *dl_fn = &ctx->nvenc_dload_funcs;
>       NVENCSTATUS err;
>       uint32_t nvenc_max_ver;
> +    uint32_t nvenc_max_major;
> +    uint32_t nvenc_max_minor;
> +    uint32_t func_ver = NV_ENCODE_API_FUNCTION_LIST_VER;
>       int ret;
> -
>       ret = cuda_load_functions(&dl_fn->cuda_dl, avctx);
>       if (ret < 0)
>           return ret;
> @@ -214,19 +226,17 @@ static av_cold int nvenc_load_libraries(AVCodecContext *avctx)
>       err = dl_fn->nvenc_dl->NvEncodeAPIGetMaxSupportedVersion(&nvenc_max_ver);
>       if (err != NV_ENC_SUCCESS)
>           return nvenc_print_error(avctx, err, "Failed to query nvenc max version");
> +    nvenc_max_major = nvenc_max_ver >> 4;
> +    nvenc_max_minor = nvenc_max_ver & 0xf;
> +    av_log(avctx, AV_LOG_VERBOSE, "nvenc build version: %d.%d, runtime version: %d.%d\n", NVENCAPI_MAJOR_VERSION, NVENCAPI_MINOR_VERSION, nvenc_max_major, nvenc_max_minor);
>   
> -    av_log(avctx, AV_LOG_VERBOSE, "Loaded Nvenc version %d.%d\n", nvenc_max_ver >> 4, nvenc_max_ver & 0xf);
> -
> -    if ((NVENCAPI_MAJOR_VERSION << 4 | NVENCAPI_MINOR_VERSION) > nvenc_max_ver) {
> -        av_log(avctx, AV_LOG_ERROR, "Driver does not support the required nvenc API version. "
> -               "Required: %d.%d Found: %d.%d\n",
> -               NVENCAPI_MAJOR_VERSION, NVENCAPI_MINOR_VERSION,
> -               nvenc_max_ver >> 4, nvenc_max_ver & 0xf);
> -        nvenc_print_driver_requirement(avctx, AV_LOG_ERROR);
> -        return AVERROR(ENOSYS);
> -    }
> +    ctx->apiver_rt = api_ver(nvenc_max_major, nvenc_max_minor); /* NVENCAPI_VERSION */
> +    ctx->config_ver_rt = struct_ver_rt(ctx, 7) | (1<<31); /* NV_ENC_CONFIG_VER */
> +    if (ctx->apiver_rt < api_ver(8, 1))
> +        ctx->config_ver_rt = struct_ver_rt(ctx, 6) | (1<<31);
> +    func_ver = struct_ver_rt(ctx, 2);
>   
> -    dl_fn->nvenc_funcs.version = NV_ENCODE_API_FUNCTION_LIST_VER;
> +    dl_fn->nvenc_funcs.version = func_ver;
>   
>       err = dl_fn->nvenc_dl->NvEncodeAPICreateInstance(&dl_fn->nvenc_funcs);
>       if (err != NV_ENC_SUCCESS)
> @@ -267,8 +277,8 @@ static av_cold int nvenc_open_session(AVCodecContext *avctx)
>       NV_ENCODE_API_FUNCTION_LIST *p_nvenc = &ctx->nvenc_dload_funcs.nvenc_funcs;
>       NVENCSTATUS ret;
>   
> -    params.version    = NV_ENC_OPEN_ENCODE_SESSION_EX_PARAMS_VER;
> -    params.apiVersion = NVENCAPI_VERSION;
> +    params.version    = struct_ver_rt(ctx, 1); // NV_ENC_OPEN_ENCODE_SESSION_EX_PARAMS_VER
> +    params.apiVersion = ctx->apiver_rt;
>       if (ctx->d3d11_device) {
>           params.device     = ctx->d3d11_device;
>           params.deviceType = NV_ENC_DEVICE_TYPE_DIRECTX;
> @@ -329,7 +339,7 @@ static int nvenc_check_cap(AVCodecContext *avctx, NV_ENC_CAPS cap)
>       NV_ENC_CAPS_PARAM params        = { 0 };
>       int ret, val = 0;
>   
> -    params.version     = NV_ENC_CAPS_PARAM_VER;
> +    params.version     = struct_ver_rt(ctx, 1); // NV_ENC_CAPS_PARAM_VER;
>       params.capsToQuery = cap;
>   
>       ret = p_nvenc->nvEncGetEncodeCaps(ctx->nvencoder, ctx->init_encode_params.encodeGUID, &params, &val);
> @@ -688,7 +698,7 @@ static av_cold void set_constqp(AVCodecContext *avctx)
>       NV_ENC_RC_PARAMS *rc = &ctx->encode_config.rcParams;
>   
>       rc->rateControlMode = NV_ENC_PARAMS_RC_CONSTQP;
> -
> +    /*rc->reservedBitField1 = 0;*/
>       if (ctx->init_qp_p >= 0) {
>           rc->constQP.qpInterP = ctx->init_qp_p;
>           if (ctx->init_qp_i >= 0 && ctx->init_qp_b >= 0) {
> @@ -1221,8 +1231,8 @@ static av_cold int nvenc_setup_encoder(AVCodecContext *avctx)
>       int res = 0;
>       int dw, dh;
>   
> -    ctx->encode_config.version = NV_ENC_CONFIG_VER;
> -    ctx->init_encode_params.version = NV_ENC_INITIALIZE_PARAMS_VER;
> +    ctx->encode_config.version = ctx->config_ver_rt;//NV_ENC_CONFIG_VER;
> +    ctx->init_encode_params.version = struct_ver_rt(ctx, 5) | (1<<31);//NV_ENC_INITIALIZE_PARAMS_VER;

More magic numbers.

>   
>       ctx->init_encode_params.encodeHeight = avctx->height;
>       ctx->init_encode_params.encodeWidth = avctx->width;
> @@ -1231,8 +1241,8 @@ static av_cold int nvenc_setup_encoder(AVCodecContext *avctx)
>   
>       nvenc_map_preset(ctx);
>   
> -    preset_config.version = NV_ENC_PRESET_CONFIG_VER;
> -    preset_config.presetCfg.version = NV_ENC_CONFIG_VER;
> +    preset_config.version = struct_ver_rt(ctx, 4) | (1<<31);// NV_ENC_PRESET_CONFIG_VER;

Yet more of them.

> +    preset_config.presetCfg.version = ctx->config_ver_rt;//NV_ENC_CONFIG_VER;
>   
>       if (IS_SDK10_PRESET(ctx->preset)) {
>   #ifdef NVENC_HAVE_NEW_PRESETS
> @@ -1260,7 +1270,7 @@ static av_cold int nvenc_setup_encoder(AVCodecContext *avctx)
>   
>       memcpy(&ctx->encode_config, &preset_config.presetCfg, sizeof(ctx->encode_config));
>   
> -    ctx->encode_config.version = NV_ENC_CONFIG_VER;
> +    ctx->encode_config.version = ctx->config_ver_rt;//NV_ENC_CONFIG_VER;
>   
>       compute_dar(avctx, &dw, &dh);
>       ctx->init_encode_params.darHeight = dh;
> @@ -1404,7 +1414,7 @@ static av_cold int nvenc_alloc_surface(AVCodecContext *avctx, int idx)
>   
>       NVENCSTATUS nv_status;
>       NV_ENC_CREATE_BITSTREAM_BUFFER allocOut = { 0 };
> -    allocOut.version = NV_ENC_CREATE_BITSTREAM_BUFFER_VER;
> +    allocOut.version = struct_ver_rt(ctx, 1);//NV_ENC_CREATE_BITSTREAM_BUFFER_VER;
>   
>       if (avctx->pix_fmt == AV_PIX_FMT_CUDA || avctx->pix_fmt == AV_PIX_FMT_D3D11) {
>           ctx->surfaces[idx].in_ref = av_frame_alloc();
> @@ -1420,7 +1430,7 @@ static av_cold int nvenc_alloc_surface(AVCodecContext *avctx, int idx)
>               return AVERROR(EINVAL);
>           }
>   
> -        allocSurf.version = NV_ENC_CREATE_INPUT_BUFFER_VER;
> +        allocSurf.version = struct_ver_rt(ctx, 1);//NV_ENC_CREATE_INPUT_BUFFER_VER;
>           allocSurf.width = avctx->width;
>           allocSurf.height = avctx->height;
>           allocSurf.bufferFmt = ctx->surfaces[idx].format;
> @@ -1503,7 +1513,7 @@ static av_cold int nvenc_setup_extradata(AVCodecContext *avctx)
>       uint32_t outSize = 0;
>       char tmpHeader[256];
>       NV_ENC_SEQUENCE_PARAM_PAYLOAD payload = { 0 };
> -    payload.version = NV_ENC_SEQUENCE_PARAM_PAYLOAD_VER;
> +    payload.version = struct_ver_rt(ctx, 1);//NV_ENC_SEQUENCE_PARAM_PAYLOAD_VER;
>   
>       payload.spsppsBuffer = tmpHeader;
>       payload.inBufferSize = sizeof(tmpHeader);
> @@ -1535,7 +1545,7 @@ av_cold int ff_nvenc_encode_close(AVCodecContext *avctx)
>   
>       /* the encoder has to be flushed before it can be closed */
>       if (ctx->nvencoder) {
> -        NV_ENC_PIC_PARAMS params        = { .version        = NV_ENC_PIC_PARAMS_VER,
> +        NV_ENC_PIC_PARAMS params        = { .version        = struct_ver_rt(ctx, 4) | (1<<31),
>                                               .encodePicFlags = NV_ENC_PIC_FLAG_EOS };

Same here

>           res = nvenc_push_context(avctx);
> @@ -1747,7 +1757,7 @@ static int nvenc_register_frame(AVCodecContext *avctx, const AVFrame *frame)
>       if (idx < 0)
>           return idx;
>   
> -    reg.version            = NV_ENC_REGISTER_RESOURCE_VER;
> +    reg.version            = struct_ver_rt(ctx, 3);// NV_ENC_REGISTER_RESOURCE_VER;
>       reg.width              = frames_ctx->width;
>       reg.height             = frames_ctx->height;
>       reg.pitch              = frame->linesize[0];
> @@ -1802,7 +1812,7 @@ static int nvenc_upload_frame(AVCodecContext *avctx, const AVFrame *frame,
>               return res;
>   
>           if (!ctx->registered_frames[reg_idx].mapped) {
> -            ctx->registered_frames[reg_idx].in_map.version = NV_ENC_MAP_INPUT_RESOURCE_VER;
> +            ctx->registered_frames[reg_idx].in_map.version = struct_ver_rt(ctx, 4);// NV_ENC_MAP_INPUT_RESOURCE_VER;
>               ctx->registered_frames[reg_idx].in_map.registeredResource = ctx->registered_frames[reg_idx].regptr;
>               nv_status = p_nvenc->nvEncMapInputResource(ctx->nvencoder, &ctx->registered_frames[reg_idx].in_map);
>               if (nv_status != NV_ENC_SUCCESS) {
> @@ -1822,7 +1832,7 @@ static int nvenc_upload_frame(AVCodecContext *avctx, const AVFrame *frame,
>       } else {
>           NV_ENC_LOCK_INPUT_BUFFER lockBufferParams = { 0 };
>   
> -        lockBufferParams.version = NV_ENC_LOCK_INPUT_BUFFER_VER;
> +        lockBufferParams.version = struct_ver_rt(ctx, 1);//NV_ENC_LOCK_INPUT_BUFFER_VER;
>           lockBufferParams.inputBuffer = nvenc_frame->input_surface;
>   
>           nv_status = p_nvenc->nvEncLockInputBuffer(ctx->nvencoder, &lockBufferParams);
> @@ -1936,7 +1946,7 @@ static int process_output_surface(AVCodecContext *avctx, AVPacket *pkt, NvencSur
>           goto error;
>       }
>   
> -    lock_params.version = NV_ENC_LOCK_BITSTREAM_VER;
> +    lock_params.version = struct_ver_rt(ctx, 1);//NV_ENC_LOCK_BITSTREAM_VER;
>   
>       lock_params.doNotWait = 0;
>       lock_params.outputBitstream = tmpoutsurf->output_surface;
> @@ -2054,7 +2064,7 @@ static void reconfig_encoder(AVCodecContext *avctx, const AVFrame *frame)
>       int reconfig_bitrate = 0, reconfig_dar = 0;
>       int dw, dh;
>   
> -    params.version = NV_ENC_RECONFIGURE_PARAMS_VER;
> +    params.version = struct_ver_rt(ctx, 1) | (1<<31);//NV_ENC_RECONFIGURE_PARAMS_VER;
>       params.reInitEncodeParams = ctx->init_encode_params;
>   
>       compute_dar(avctx, &dw, &dh);
> @@ -2148,7 +2158,7 @@ static int nvenc_send_frame(AVCodecContext *avctx, const AVFrame *frame)
>       NV_ENCODE_API_FUNCTION_LIST *p_nvenc = &dl_fn->nvenc_funcs;
>   
>       NV_ENC_PIC_PARAMS pic_params = { 0 };
> -    pic_params.version = NV_ENC_PIC_PARAMS_VER;
> +    pic_params.version = struct_ver_rt(ctx, 4) | (1<<31);//NV_ENC_PIC_PARAMS_VER;
>   
>       if ((!ctx->cu_context && !ctx->d3d11_device) || !ctx->nvencoder)
>           return AVERROR(EINVAL);
> diff --git a/libavcodec/nvenc.h b/libavcodec/nvenc.h
> index fb3820f7cf..6a39391276 100644
> --- a/libavcodec/nvenc.h
> +++ b/libavcodec/nvenc.h
> @@ -146,6 +146,9 @@ typedef struct NvencContext
>   {
>       AVClass *avclass;
>   
> +    uint32_t apiver_rt;
> +    uint32_t config_ver_rt;
> +
>       NvencDynLoadFunctions nvenc_dload_funcs;
>   
>       NV_ENC_INITIALIZE_PARAMS init_encode_params;
> 

What is the logic behind picking those numbers? What happens if a struct 
gets updated, and ffmpeg wants to use the new fields when available, 
like happened plenty of times?


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