From patchwork Thu Dec 23 02:33:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laurent Pinchart X-Patchwork-Id: 15213 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 1D1EDC3258 for ; Thu, 23 Dec 2021 02:33:42 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 0737560905; Thu, 23 Dec 2021 03:33:41 +0100 (CET) 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="e3ToY9V3"; 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 A22FD605A8 for ; Thu, 23 Dec 2021 03:33:38 +0100 (CET) Received: from pendragon.lan (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 4B03AB7E for ; Thu, 23 Dec 2021 03:33:38 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1640226818; bh=37oRnMtXLu06mgpjv2ANvG+8Qw2DHBzZ4MJw07lCcgs=; h=From:To:Subject:Date:In-Reply-To:References:From; b=e3ToY9V3yqpJus9qXHbPKRV426PrFidFH+htJueauGIfBalBCQt2U5LaSihNxdiBd LOHe3hcxJct6pGzwMPZbKRiOIuZ7DArMQ6OKIcElACGpYAkhVb+rUVdssGAqlvlPZQ yd9WoYwqtn577KGlxuqJUv1k5iLSsVAhd+JoNeB4= From: Laurent Pinchart To: libcamera-devel@lists.libcamera.org Date: Thu, 23 Dec 2021 04:33:30 +0200 Message-Id: <20211223023331.13505-2-laurent.pinchart@ideasonboard.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211223023331.13505-1-laurent.pinchart@ideasonboard.com> References: <20211223023331.13505-1-laurent.pinchart@ideasonboard.com> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH 1/2] libcamera: media_device: Move recursive lock handling to pipeline handler 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 MediaDevice lock is meant to prevent concurrent usage of multiple cameras from the same pipeline handlers. As media devices are acquired by pipeline handlers, we can't have multiple pipeline handlers trying to lock the same media device. The recursive locking detection can thus be moved to the pipeline handler. This simplifies the media device implementation that now implements true lock semantics, and prepares for support of concurrent camera usage. Signed-off-by: Laurent Pinchart --- include/libcamera/internal/media_device.h | 1 - include/libcamera/internal/pipeline_handler.h | 2 ++ src/libcamera/media_device.cpp | 14 +------------- src/libcamera/pipeline_handler.cpp | 13 ++++++++++++- 4 files changed, 15 insertions(+), 15 deletions(-) diff --git a/include/libcamera/internal/media_device.h b/include/libcamera/internal/media_device.h index af0b25b731eb..6e2a63f38229 100644 --- a/include/libcamera/internal/media_device.h +++ b/include/libcamera/internal/media_device.h @@ -86,7 +86,6 @@ private: UniqueFD fd_; bool valid_; bool acquired_; - bool lockOwner_; std::map objects_; std::vector entities_; diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h index ec986a518b5c..a7331cedfb16 100644 --- a/include/libcamera/internal/pipeline_handler.h +++ b/include/libcamera/internal/pipeline_handler.h @@ -88,6 +88,8 @@ private: const char *name_; + bool lockOwner_; + friend class PipelineHandlerFactory; }; diff --git a/src/libcamera/media_device.cpp b/src/libcamera/media_device.cpp index 0b7940182d0c..941f86c25f66 100644 --- a/src/libcamera/media_device.cpp +++ b/src/libcamera/media_device.cpp @@ -63,8 +63,7 @@ LOG_DEFINE_CATEGORY(MediaDevice) * populate() before the media graph can be queried. */ MediaDevice::MediaDevice(const std::string &deviceNode) - : deviceNode_(deviceNode), valid_(false), acquired_(false), - lockOwner_(false) + : deviceNode_(deviceNode), valid_(false), acquired_(false) { } @@ -145,15 +144,9 @@ bool MediaDevice::lock() if (!fd_.isValid()) return false; - /* Do not allow nested locking in the same libcamera instance. */ - if (lockOwner_) - return false; - if (lockf(fd_.get(), F_TLOCK, 0)) return false; - lockOwner_ = true; - return true; } @@ -171,11 +164,6 @@ void MediaDevice::unlock() if (!fd_.isValid()) return; - if (!lockOwner_) - return; - - lockOwner_ = false; - lockf(fd_.get(), F_ULOCK, 0); } diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp index 0bc0e341b9e7..b2ee4ec0ce87 100644 --- a/src/libcamera/pipeline_handler.cpp +++ b/src/libcamera/pipeline_handler.cpp @@ -67,7 +67,7 @@ LOG_DEFINE_CATEGORY(Pipeline) * respective factories. */ PipelineHandler::PipelineHandler(CameraManager *manager) - : manager_(manager) + : manager_(manager), lockOwner_(false) { } @@ -155,6 +155,10 @@ MediaDevice *PipelineHandler::acquireMediaDevice(DeviceEnumerator *enumerator, */ bool PipelineHandler::lock() { + /* Do not allow nested locking in the same libcamera instance. */ + if (lockOwner_) + return false; + for (std::shared_ptr &media : mediaDevices_) { if (!media->lock()) { unlock(); @@ -162,6 +166,8 @@ bool PipelineHandler::lock() } } + lockOwner_ = true; + return true; } @@ -177,8 +183,13 @@ bool PipelineHandler::lock() */ void PipelineHandler::unlock() { + if (lockOwner_) + return; + for (std::shared_ptr &media : mediaDevices_) media->unlock(); + + lockOwner_ = false; } /**