From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3CEFC47404 for ; Fri, 4 Oct 2019 09:21:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8112E20867 for ; Fri, 4 Oct 2019 09:21:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731470AbfJDJVY (ORCPT ); Fri, 4 Oct 2019 05:21:24 -0400 Received: from lb3-smtp-cloud7.xs4all.net ([194.109.24.31]:49107 "EHLO lb3-smtp-cloud7.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727587AbfJDJVY (ORCPT ); Fri, 4 Oct 2019 05:21:24 -0400 Received: from [192.168.2.10] ([46.9.232.237]) by smtp-cloud7.xs4all.net with ESMTPA id GJlwivf8kjZ8vGJlziswOs; Fri, 04 Oct 2019 11:21:22 +0200 Subject: Re: [PATCH v2 3/6] media: v4l2-mem2mem: add stateless_(try_)decoder_cmd ioctl helpers To: Jernej Skrabec , mchehab@kernel.org, paul.kocialkowski@bootlin.com, mripard@kernel.org, pawel@osciak.com, m.szyprowski@samsung.com, kyungmin.park@samsung.com, tfiga@chromium.org, wens@csie.org Cc: gregkh@linuxfoundation.org, boris.brezillon@collabora.com, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org, linux-arm-kernel@lists.infradead.org, ezequiel@collabora.com, jonas@kwiboo.se References: <20190929200023.215831-1-jernej.skrabec@siol.net> <20190929200023.215831-4-jernej.skrabec@siol.net> From: Hans Verkuil Message-ID: <6c7eeaf1-18bb-1c7e-7938-a3eb5af100b6@xs4all.nl> Date: Fri, 4 Oct 2019 11:21:12 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20190929200023.215831-4-jernej.skrabec@siol.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfNHxv0MOKVAOjLAe6G4CBfcHcYTNr7KvCzEK5brMzn3ZewBV+0xbPvwcwJDQcp8ul8eIBmxzXkX1txxx+hZvvzm38lHBPu5jyPYMWkFgiWLkB5pqH676 fboONHHLgY1hhv50icOJjIk7Mx0A8PhLej+PEhTPbLbCerxtslbf7QKukn3nwby2XhwQqccJeVBfW/24bEc/L4Jk8gnW30K+2XeCJOoysZB8IkE5pqsnzvg0 NMuG7lI2b1+8HCRWmjj+SQ5qSiGLYSujq6J6CKoJT2gDTeW4Z6b+V1DT03vIwaJWaEh1fVScwiIzLlQFWeWQ6w5jvIDBtgDzvy+oNohMnw6jNOUn5hkOozI6 Yk9gyKkeDLqbOEU96E2JaHy/4wbPhd+Ml9aXEXhNE/ssKVtKCVuK3NoRtDhEC8+4zpnMblzKXcVmusxK2Xex7TGU8j+vmNdjnuqMEzgoIF1z/UD/zLNy7WNs M6kV1B+XGnxac6NCTLZjlVmiPqIjyzfPkunDdXpQhHB3MPM2coK2MEN5k7iqA2IzMQivBgTxEjLTKkxq2vCMVBOwZ2jTukJhtTDY9mLdI3osLmhLUEmPJbTB RVJO80w3CvGvfkkD6URjuL6h5NoKFfQERYxIHZnp+wKdvUSsNtUNII5dOKu8fYO88hrhMxu3Qs/p01EsWK+QsnjoGa4F4Uy6H+VCAemmNbWYbrfuO+feoItY Ezt4XtEQc1vLwi9nANW0Gvlzguxtz/ZBx7ORXGURUqGy8BaZ81/gVg== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/29/19 10:00 PM, Jernej Skrabec wrote: > These helpers are used by stateless codecs when they support multiple > slices per frame and hold capture buffer flag is set. It's expected that > all such codecs will use this code. > > Signed-off-by: Jernej Skrabec > --- > drivers/media/v4l2-core/v4l2-mem2mem.c | 35 ++++++++++++++++++++++++++ > include/media/v4l2-mem2mem.h | 4 +++ > 2 files changed, 39 insertions(+) > > diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c > index 19937dd3c6f6..2677a07e4c9b 100644 > --- a/drivers/media/v4l2-core/v4l2-mem2mem.c > +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c > @@ -1154,6 +1154,41 @@ int v4l2_m2m_ioctl_try_decoder_cmd(struct file *file, void *fh, > } > EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_try_decoder_cmd); > > +int v4l2_m2m_ioctl_stateless_try_decoder_cmd(struct file *file, void *fh, > + struct v4l2_decoder_cmd *dc) > +{ > + if (dc->cmd != V4L2_DEC_CMD_FLUSH) > + return -EINVAL; > + > + dc->flags = 0; > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_stateless_try_decoder_cmd); > + > +int v4l2_m2m_ioctl_stateless_decoder_cmd(struct file *file, void *priv, > + struct v4l2_decoder_cmd *dc) > +{ > + struct v4l2_fh *fh = file->private_data; > + struct vb2_v4l2_buffer *out_vb, *cap_vb; > + int ret; > + > + ret = v4l2_m2m_ioctl_stateless_try_decoder_cmd(file, priv, dc); > + if (ret < 0) > + return ret; > + > + out_vb = v4l2_m2m_last_src_buf(fh->m2m_ctx); > + cap_vb = v4l2_m2m_last_dst_buf(fh->m2m_ctx); I think this should be v4l2_m2m_next_dst_buf. If multiple capture buffers were queued up, then it can only be the first capture buffer that can be 'HELD'. This might solve the race condition you saw with ffmpeg. Regards, Hans > + > + if (out_vb) > + out_vb->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF; > + else if (cap_vb && cap_vb->is_held) > + v4l2_m2m_buf_done(cap_vb, VB2_BUF_STATE_DONE); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_stateless_decoder_cmd); > + > /* > * v4l2_file_operations helpers. It is assumed here same lock is used > * for the output and the capture buffer queue. > diff --git a/include/media/v4l2-mem2mem.h b/include/media/v4l2-mem2mem.h > index c9fa96c8eed1..8ae2f56c7fa3 100644 > --- a/include/media/v4l2-mem2mem.h > +++ b/include/media/v4l2-mem2mem.h > @@ -714,6 +714,10 @@ int v4l2_m2m_ioctl_try_encoder_cmd(struct file *file, void *fh, > struct v4l2_encoder_cmd *ec); > int v4l2_m2m_ioctl_try_decoder_cmd(struct file *file, void *fh, > struct v4l2_decoder_cmd *dc); > +int v4l2_m2m_ioctl_stateless_try_decoder_cmd(struct file *file, void *fh, > + struct v4l2_decoder_cmd *dc); > +int v4l2_m2m_ioctl_stateless_decoder_cmd(struct file *file, void *priv, > + struct v4l2_decoder_cmd *dc); > int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma); > __poll_t v4l2_m2m_fop_poll(struct file *file, poll_table *wait); > >