From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 340EC44227 for ; Fri, 2 Sep 2022 21:00:10 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id A9DF668B9DC; Sat, 3 Sep 2022 00:00:07 +0300 (EEST) Received: from mail0.khirnov.net (red.khirnov.net [176.97.15.12]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 7D6CF68B99E for ; Sat, 3 Sep 2022 00:00:00 +0300 (EEST) Received: from localhost (localhost [IPv6:::1]) by mail0.khirnov.net (Postfix) with ESMTP id E6F22240D0E; Fri, 2 Sep 2022 22:59:59 +0200 (CEST) Received: from mail0.khirnov.net ([IPv6:::1]) by localhost (mail0.khirnov.net [IPv6:::1]) (amavisd-new, port 10024) with ESMTP id kIo3IrbTC8gH; Fri, 2 Sep 2022 22:59:59 +0200 (CEST) Received: from libav.khirnov.net (libav.khirnov.net [IPv6:2a00:c500:561:201::7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "libav.khirnov.net", Issuer "smtp.khirnov.net SMTP CA" (verified OK)) by mail0.khirnov.net (Postfix) with ESMTPS id 22411240D03; Fri, 2 Sep 2022 22:59:59 +0200 (CEST) Received: by libav.khirnov.net (Postfix, from userid 1000) id 4A12D3A0520; Fri, 2 Sep 2022 22:59:50 +0200 (CEST) From: Anton Khirnov To: ffmpeg-devel@ffmpeg.org Date: Fri, 2 Sep 2022 22:59:32 +0200 Message-Id: <20220902205932.17883-1-anton@khirnov.net> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Subject: [FFmpeg-devel] [PATCH] lavc/pthread_frame: avoid leaving stale hwaccel state in worker threads X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Steve Lhomme Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: This state is not refcounted, so make sure it always has a well-defined owner. --- Steve, could you please test this? --- libavcodec/pthread_frame.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/libavcodec/pthread_frame.c b/libavcodec/pthread_frame.c index 08a6f98898..9b44e2e698 100644 --- a/libavcodec/pthread_frame.c +++ b/libavcodec/pthread_frame.c @@ -148,6 +148,10 @@ typedef struct FrameThreadContext { * Set for the first N packets, where N is the number of threads. * While it is set, ff_thread_en/decode_frame won't return any results. */ + + const AVHWAccel *stash_hwaccel; + void *stash_hwaccel_context; + void *stash_hwaccel_priv; } FrameThreadContext; #if FF_API_THREAD_SAFE_CALLBACKS @@ -228,9 +232,17 @@ FF_ENABLE_DEPRECATION_WARNINGS ff_thread_finish_setup(avctx); if (p->hwaccel_serializing) { + /* wipe hwaccel state to avoid stale pointers lying around; + * the state was transferred to FrameThreadContext in + * ff_thread_finish_setup(), so nothing is leaked */ + avctx->hwaccel = NULL; + avctx->hwaccel_context = NULL; + avctx->internal->hwaccel_priv_data = NULL; + p->hwaccel_serializing = 0; pthread_mutex_unlock(&p->parent->hwaccel_mutex); } + av_assert0(!avctx->hwaccel); if (p->async_serializing) { p->async_serializing = 0; @@ -294,9 +306,6 @@ static int update_context_from_thread(AVCodecContext *dst, AVCodecContext *src, dst->color_range = src->color_range; dst->chroma_sample_location = src->chroma_sample_location; - dst->hwaccel = src->hwaccel; - dst->hwaccel_context = src->hwaccel_context; - dst->sample_rate = src->sample_rate; dst->sample_fmt = src->sample_fmt; #if FF_API_OLD_CHANNEL_LAYOUT @@ -309,8 +318,6 @@ FF_ENABLE_DEPRECATION_WARNINGS if (err < 0) return err; - dst->internal->hwaccel_priv_data = src->internal->hwaccel_priv_data; - if (!!dst->hw_frames_ctx != !!src->hw_frames_ctx || (dst->hw_frames_ctx && dst->hw_frames_ctx->data != src->hw_frames_ctx->data)) { av_buffer_unref(&dst->hw_frames_ctx); @@ -450,6 +457,12 @@ static int submit_packet(PerThreadContext *p, AVCodecContext *user_avctx, pthread_mutex_unlock(&p->mutex); return err; } + + /* transfer hwaccel state stashed from previous thread, if any */ + av_assert0(!p->avctx->hwaccel); + FFSWAP(const AVHWAccel*, p->avctx->hwaccel, fctx->stash_hwaccel); + FFSWAP(void*, p->avctx->hwaccel_context, fctx->stash_hwaccel_context); + FFSWAP(void*, p->avctx->internal->hwaccel_priv_data, fctx->stash_hwaccel_priv); } av_packet_unref(p->avpkt); @@ -655,6 +668,13 @@ void ff_thread_finish_setup(AVCodecContext *avctx) { async_lock(p->parent); } + /* save hwaccel state for passing to the next thread; + * this is done here so that this worker thread can wipe its own hwaccel + * state after decoding, without requiring synchronization */ + p->parent->stash_hwaccel = avctx->hwaccel; + p->parent->stash_hwaccel_context = avctx->hwaccel_context; + p->parent->stash_hwaccel_priv = avctx->internal->hwaccel_priv_data; + pthread_mutex_lock(&p->progress_mutex); if(atomic_load(&p->state) == STATE_SETUP_FINISHED){ av_log(avctx, AV_LOG_WARNING, "Multiple ff_thread_finish_setup() calls\n"); @@ -761,6 +781,13 @@ void ff_frame_thread_free(AVCodecContext *avctx, int thread_count) av_freep(&fctx->threads); ff_pthread_free(fctx, thread_ctx_offsets); + /* if we have stashed hwaccel state, move it to the user-facing context, + * so it will be freed in avcodec_close() */ + av_assert0(!avctx->hwaccel); + FFSWAP(const AVHWAccel*, avctx->hwaccel, fctx->stash_hwaccel); + FFSWAP(void*, avctx->hwaccel_context, fctx->stash_hwaccel_context); + FFSWAP(void*, avctx->internal->hwaccel_priv_data, fctx->stash_hwaccel_priv); + av_freep(&avctx->internal->thread_ctx); } -- 2.35.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".