From patchwork Fri Sep 10 15:49:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kieran Bingham X-Patchwork-Id: 13811 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 022BABDC71 for ; Fri, 10 Sep 2021 15:49:30 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 6A31A69170; Fri, 10 Sep 2021 17:49:29 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="O2K0VoQA"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id E936269169 for ; Fri, 10 Sep 2021 17:49:27 +0200 (CEST) Received: from Monstersaurus.local (cpc89244-aztw30-2-0-cust3082.18-1.cable.virginm.net [86.31.172.11]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 6ACAD883; Fri, 10 Sep 2021 17:49:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1631288967; bh=08yWEDDq24zqLw/gRWvA2gWpAzaZ2w6b3bcRT5ogu+I=; h=From:To:Cc:Subject:Date:From; b=O2K0VoQAPyV1lByk7HgqCjRQuWSZEcrORrC5saW5sZSGYCT2KdTSxQd1Ie+OIEwlh Oid9QZZw6f8rKJOnYRfykQbalVDLSatF5gjPxf5Ygqfvrv0+yoLu6TuleXJnT5gR/g V99BJDuR87rVlHSpgZXrhObJZvs7PSWGWC2TNS/w= From: Kieran Bingham To: libcamera devel , Jean-Michel Hautbois Date: Fri, 10 Sep 2021 16:49:24 +0100 Message-Id: <20210910154924.117857-1-kieran.bingham@ideasonboard.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Subject: [libcamera-devel] [RFC PATCH] ipa: ipu3: Clear incoming parameter use flags X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" The incoming params buffer may contain uninitialised data, or the parameters of previously queued frames. Clearing the entire buffer may be an expensive operation, and the kernel will only read from structures which have their associated use-flag set. It is the responsibility of the algorithms to set the use flags accordingly for any data structure they update during prepare(). Signed-off-by: Kieran Bingham Reviewed-by: Jean-Michel Hautbois Tested-by: Jean-Michel Hautbois Reviewed-by: Laurent Pinchart --- Yes, the commit message is the same as the comment before the line. I felt the text was worthy of documenting the clearing of the flags, and ensuring that it's documented in the code that the algorithms are responsible for setting their use flag of any structure they modify. Note that this is sent compile tested only, as it's something I noticed, while writing documentation and wanted to check. src/ipa/ipu3/ipu3.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp index c925cf642611..30d2a53903ec 100644 --- a/src/ipa/ipu3/ipu3.cpp +++ b/src/ipa/ipu3/ipu3.cpp @@ -457,6 +457,17 @@ void IPAIPU3::processControls([[maybe_unused]] unsigned int frame, void IPAIPU3::fillParams(unsigned int frame, ipu3_uapi_params *params) { + /* + * The incoming params buffer may contain uninitialised data, or the + * parameters of previously queued frames. Clearing the entire buffer + * may be an expensive operation, and the kernel will only read from + * structures which have their associated use-flag set. + * + * It is the responsibility of the algorithms to set the use flags + * accordingly for any data structure they update during prepare(). + */ + params->use = {}; + for (auto const &algo : algorithms_) algo->prepare(context_, params);