From patchwork Mon Mar 2 04:12:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sergey Senozhatsky X-Patchwork-Id: 61867 Received: from vger.kernel.org ([209.132.180.67]) by www.linuxtv.org with esmtp (Exim 4.92) (envelope-from ) id 1j8cPe-00H0dH-SD; Mon, 02 Mar 2020 04:10:39 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726811AbgCBEMY (ORCPT + 1 other); Sun, 1 Mar 2020 23:12:24 -0500 Received: from mail-pg1-f194.google.com ([209.85.215.194]:34456 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726758AbgCBEMX (ORCPT ); Sun, 1 Mar 2020 23:12:23 -0500 Received: by mail-pg1-f194.google.com with SMTP id t3so4759135pgn.1 for ; Sun, 01 Mar 2020 20:12:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=B8nUcMBqmV2MqPtUQIaeg61WlAypNvWpr/qBj0Tv7NQ=; b=H9TZNADJiJ+TG4xU1inFGhGNnlHK9zgdyeHHXngKzbZiQQDPAejY1YTA63cGSgjhIa nIVy1G2Jh6kDLjrImrx5PDxJINTnmpwsRaw5nAxB4BKlb64ZEtNRveNJvBdkA3Q63rZg h4Gy+BJ5W4yd9JhJhJ9xE/w7k590FrBcyhceM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=B8nUcMBqmV2MqPtUQIaeg61WlAypNvWpr/qBj0Tv7NQ=; b=Jz3o3UXjzIq1TKuK+oKEc7i4Tm6IjhIT8jDx+ay3UiRXs9TIVjicZzbb30LZjbt0YZ EZtVrBV1tc1EwKvKyhoyDcr6wxNx/kJo4OzaqfUhVmBElgL9SHMosr+AGJ5hwbEpEvu+ 3L+D1AP+d4Bqn5xEDAaPXUDrCmO6qU5pE+btJpNIADoIn9ObESYNu6buPJ63lMf5qx8B 4HyJaLaDKeCh2ztKtwG8+x/CJvwhNCIRbVauc1xvdjW5+79sLy32BQLtdEQ0+YEdlwo6 v3d4Yj/Rrk2T2c+LiidNzFEwPlv/sBHHvTbI/1B/yEv+xqEGzOmPQ/loi7Fprpqkr/wa S0Ig== X-Gm-Message-State: APjAAAXMvY97zPk1X/goyjZCuxPQsvpUS2jfLp4wHGU1S+qqak09E4Ox n7lINMN1PnunVNykkKWSEbhcnA== X-Google-Smtp-Source: APXvYqx5IVVGmhE21w/I3CEw5NMLpL868xHNe0N+DRcF8FJsK86WdNxQZUgVYcoaMl1J1+PB3lxLYQ== X-Received: by 2002:a63:565e:: with SMTP id g30mr17254989pgm.206.1583122342748; Sun, 01 Mar 2020 20:12:22 -0800 (PST) Received: from tigerii.tok.corp.google.com ([2401:fa00:8f:203:5bbb:c872:f2b1:f53b]) by smtp.gmail.com with ESMTPSA id d82sm1698114pfd.187.2020.03.01.20.12.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 01 Mar 2020 20:12:22 -0800 (PST) From: Sergey Senozhatsky To: Hans Verkuil , Tomasz Figa Cc: Mauro Carvalho Chehab , Kyungmin Park , Marek Szyprowski , Sakari Ailus , Laurent Pinchart , Pawel Osciak , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: [PATCHv4 00/11] Implement V4L2_BUF_FLAG_NO_CACHE_* flags Date: Mon, 2 Mar 2020 13:12:02 +0900 Message-Id: <20200302041213.27662-1-senozhatsky@chromium.org> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hello, v4 of the series. Typos and grammar fixes. Previous series: v3 link: https://lore.kernel.org/lkml/20200226111529.180197-1-senozhatsky@chromium.org v2 link: https://lore.kernel.org/lkml/20200204025641.218376-1-senozhatsky@chromium.org/ v1 link: https://lore.kernel.org/lkml/20191217032034.54897-1-senozhatsky@chromium.org/ Series Intro ======================================================================== This is a reworked version of the vb2 cache hints (V4L2_BUF_FLAG_NO_CACHE_INVALIDATE / V4L2_BUF_FLAG_NO_CACHE_CLEAN) support patch series which previsouly was developed by Sakari and Laurent [0]. The patch set attempts to preserve the existing behvaiour - cache sync is performed in ->prepare() and ->finish() (unless the buffer is DMA exported). User space can request “default behavior” override with cache management hints, which are handled on a per-buffer basis and should be supplied with v4l2_buffer ->flags during buffer preparation. There are two possible hints: - V4L2_BUF_FLAG_NO_CACHE_INVALIDATE No cache sync on ->finish() - V4L2_BUF_FLAG_NO_CACHE_CLEAN No cache sync on ->prepare() In order to keep things on the safe side, we also require driver to explicitly state which of its queues (if any) support user space cache management hints (such queues should have ->allow_cache_hints bit set). The patch set also (to some extent) simplifies allocators' ->prepare() and ->finish() callbacks. Namely, we move cache management decision making to the upper - core - layer. For example, if, previously, we would have something like this vb2_buffer_done() vb2_dc_finish() if (buf->db_attach) return; where each allocators' ->finish() callback would either bail out (DMA exported buffer, for instance) or sync, now that "bail out or sync" decision is made before we call into the allocator. Along with cache management hints, user space is also able to adjust queue's memory consistency attributes. Memory consistency attribute (dma_attrs) is per-queue, yet it plays its role on the allocator level, when we allocate buffers’ private memory (planes). For the time being, only one consistency attribute is supported: DMA_ATTR_NON_CONSISTENT. [0] https://www.mail-archive.com/linux-media@vger.kernel.org/msg112459.html Sergey Senozhatsky (11): videobuf2: add cache management members videobuf2: handle V4L2 buffer cache flags videobuf2: add V4L2_FLAG_MEMORY_NON_CONSISTENT flag videobuf2: add queue memory consistency parameter videobuf2: handle V4L2_FLAG_MEMORY_NON_CONSISTENT flag videobuf2: factor out planes prepare/finish functions videobuf2: do not sync caches when we are allowed not to videobuf2: check ->synced flag in prepare() and finish() videobuf2: add begin/end cpu_access callbacks to dma-contig videobuf2: add begin/end cpu_access callbacks to dma-sg videobuf2: don't test db_attach in dma-contig prepare and finish Documentation/media/uapi/v4l/buffer.rst | 29 +++++ .../media/uapi/v4l/vidioc-create-bufs.rst | 7 +- .../media/uapi/v4l/vidioc-reqbufs.rst | 18 ++- .../media/common/videobuf2/videobuf2-core.c | 110 +++++++++++++----- .../common/videobuf2/videobuf2-dma-contig.c | 39 ++++++- .../media/common/videobuf2/videobuf2-dma-sg.c | 36 ++++-- .../media/common/videobuf2/videobuf2-v4l2.c | 82 ++++++++++++- drivers/media/dvb-core/dvb_vb2.c | 2 +- drivers/media/v4l2-core/v4l2-ioctl.c | 5 +- include/media/videobuf2-core.h | 28 ++++- include/uapi/linux/videodev2.h | 11 +- 11 files changed, 310 insertions(+), 57 deletions(-)