From patchwork Thu Aug 29 10:55:39 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 823763 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B5C518FC70 for ; Thu, 29 Aug 2024 10:58:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724929107; cv=none; b=f7h/2NBtRcd/1bczVPcSVWlxW8kt5NNK5fUf2NF40btzZzBeDfO4dez0osQe12HqcN3N2neJrM49/jBX3KxfrAqBfdBAlkGHPPnRKhCR8zte9VaqsaNqOsfRwpKZPXtYtumrl/Nvxe2Iitin34IZyLSMFvvEj9DYxlsVpM682aM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724929107; c=relaxed/simple; bh=AAGORkCHZ0aT2uw3IHcK1u0bLNOBeBGzPuudZguZBUA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SQ7DZaL3KJ92w9kNgor+KIoq+Y+rpN8wAJ75RwZwrAu6tfCRb52hceFVHonaaj4uePo1o4i0XXm/xWt+WgcMvC5YEglkgYwQLa+NPxh8JLkNCvmH5qPE4sBl69qoITB+jQbi+8idQdSqasV/t2q4JsxRYJP5tOJEBGpXfp/YZ+g= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C55EC4CEC5; Thu, 29 Aug 2024 10:58:25 +0000 (UTC) From: Hans Verkuil To: linux-media@vger.kernel.org Cc: Nicolas Dufresne , Sebastian Fricke , Hans Verkuil Subject: [PATCHv3 3/3] media: mc: add debugfs node to keep track of requests Date: Thu, 29 Aug 2024 12:55:39 +0200 Message-ID: X-Mailer: git-send-email 2.43.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Keep track of the number of requests and request objects of a media device. Helps to verify that all request-related memory is freed. Signed-off-by: Hans Verkuil --- drivers/media/mc/mc-device.c | 30 ++++++++++++++++++++++++++++++ drivers/media/mc/mc-devnode.c | 5 +++++ drivers/media/mc/mc-request.c | 6 ++++++ include/media/media-device.h | 9 +++++++++ include/media/media-devnode.h | 4 ++++ include/media/media-request.h | 2 ++ 6 files changed, 56 insertions(+) diff --git a/drivers/media/mc/mc-device.c b/drivers/media/mc/mc-device.c index c0dd4ae57227..5a458160200a 100644 --- a/drivers/media/mc/mc-device.c +++ b/drivers/media/mc/mc-device.c @@ -679,6 +679,23 @@ void media_device_unregister_entity(struct media_entity *entity) } EXPORT_SYMBOL_GPL(media_device_unregister_entity); +#ifdef CONFIG_DEBUG_FS +/* + * Log the state of media requests. + * Very useful for debugging. + */ +static int media_device_requests(struct seq_file *file, void *priv) +{ + struct media_device *dev = dev_get_drvdata(file->private); + + seq_printf(file, "number of requests: %d\n", + atomic_read(&dev->num_requests)); + seq_printf(file, "number of request objects: %d\n", + atomic_read(&dev->num_request_objects)); + return 0; +} +#endif + void media_device_init(struct media_device *mdev) { INIT_LIST_HEAD(&mdev->entities); @@ -697,6 +714,9 @@ void media_device_init(struct media_device *mdev) media_set_bus_info(mdev->bus_info, sizeof(mdev->bus_info), mdev->dev); + atomic_set(&mdev->num_requests, 0); + atomic_set(&mdev->num_request_objects, 0); + dev_dbg(mdev->dev, "Media device initialized\n"); } EXPORT_SYMBOL_GPL(media_device_init); @@ -748,6 +768,15 @@ int __must_check __media_device_register(struct media_device *mdev, dev_dbg(mdev->dev, "Media device registered\n"); +#ifdef CONFIG_DEBUG_FS + if (!media_debugfs_root) + media_debugfs_root = debugfs_create_dir("media", NULL); + mdev->media_dir = debugfs_create_dir(dev_name(&devnode->dev), + media_debugfs_root); + debugfs_create_devm_seqfile(&devnode->dev, "requests", + mdev->media_dir, media_device_requests); +#endif + return 0; } EXPORT_SYMBOL_GPL(__media_device_register); @@ -824,6 +853,7 @@ void media_device_unregister(struct media_device *mdev) dev_dbg(mdev->dev, "Media device unregistered\n"); + debugfs_remove_recursive(mdev->media_dir); device_remove_file(&mdev->devnode->dev, &dev_attr_model); media_devnode_unregister(mdev->devnode); /* devnode free is handled in media_devnode_*() */ diff --git a/drivers/media/mc/mc-devnode.c b/drivers/media/mc/mc-devnode.c index 318e267e798e..e01764fc1491 100644 --- a/drivers/media/mc/mc-devnode.c +++ b/drivers/media/mc/mc-devnode.c @@ -45,6 +45,9 @@ static dev_t media_dev_t; static DEFINE_MUTEX(media_devnode_lock); static DECLARE_BITMAP(media_devnode_nums, MEDIA_NUM_DEVICES); +/* debugfs */ +struct dentry *media_debugfs_root; + /* Called when the last user of the media device exits. */ static void media_devnode_release(struct device *cd) { @@ -237,6 +240,7 @@ int __must_check media_devnode_register(struct media_device *mdev, if (devnode->parent) devnode->dev.parent = devnode->parent; dev_set_name(&devnode->dev, "media%d", devnode->minor); + dev_set_drvdata(&devnode->dev, mdev); device_initialize(&devnode->dev); /* Part 2: Initialize the character device */ @@ -314,6 +318,7 @@ static int __init media_devnode_init(void) static void __exit media_devnode_exit(void) { + debugfs_remove_recursive(media_debugfs_root); bus_unregister(&media_bus_type); unregister_chrdev_region(media_dev_t, MEDIA_NUM_DEVICES); } diff --git a/drivers/media/mc/mc-request.c b/drivers/media/mc/mc-request.c index 1ad725522a7d..dcf43ddca368 100644 --- a/drivers/media/mc/mc-request.c +++ b/drivers/media/mc/mc-request.c @@ -75,6 +75,7 @@ static void media_request_release(struct kref *kref) mdev->ops->req_free(req); else kfree(req); + atomic_dec(&mdev->num_requests); } void media_request_put(struct media_request *req) @@ -332,6 +333,7 @@ int media_request_alloc(struct media_device *mdev, int *alloc_fd) snprintf(req->debug_str, sizeof(req->debug_str), "%u:%d", atomic_inc_return(&mdev->request_id), fd); + atomic_inc(&mdev->num_requests); dev_dbg(mdev->dev, "request: allocated %s\n", req->debug_str); fd_install(fd, filp); @@ -355,10 +357,12 @@ static void media_request_object_release(struct kref *kref) struct media_request_object *obj = container_of(kref, struct media_request_object, kref); struct media_request *req = obj->req; + struct media_device *mdev = obj->mdev; if (WARN_ON(req)) media_request_object_unbind(obj); obj->ops->release(obj); + atomic_dec(&mdev->num_request_objects); } struct media_request_object * @@ -423,6 +427,7 @@ int media_request_object_bind(struct media_request *req, obj->req = req; obj->ops = ops; obj->priv = priv; + obj->mdev = req->mdev; if (is_buffer) list_add_tail(&obj->list, &req->objects); @@ -430,6 +435,7 @@ int media_request_object_bind(struct media_request *req, list_add(&obj->list, &req->objects); req->num_incomplete_objects++; ret = 0; + atomic_inc(&obj->mdev->num_request_objects); unlock: spin_unlock_irqrestore(&req->lock, flags); diff --git a/include/media/media-device.h b/include/media/media-device.h index 53d2a16a70b0..749c327e3c58 100644 --- a/include/media/media-device.h +++ b/include/media/media-device.h @@ -11,6 +11,7 @@ #ifndef _MEDIA_DEVICE_H #define _MEDIA_DEVICE_H +#include #include #include #include @@ -106,6 +107,9 @@ struct media_device_ops { * @ops: Operation handler callbacks * @req_queue_mutex: Serialise the MEDIA_REQUEST_IOC_QUEUE ioctl w.r.t. * other operations that stop or start streaming. + * @num_requests: number of associated requests + * @num_request_objects: number of associated request objects + * @media_dir: DebugFS media directory * @request_id: Used to generate unique request IDs * * This structure represents an abstract high-level media device. It allows easy @@ -179,6 +183,11 @@ struct media_device { const struct media_device_ops *ops; struct mutex req_queue_mutex; + atomic_t num_requests; + atomic_t num_request_objects; + + /* debugfs */ + struct dentry *media_dir; atomic_t request_id; }; diff --git a/include/media/media-devnode.h b/include/media/media-devnode.h index d27c1c646c28..dbcabeffcb57 100644 --- a/include/media/media-devnode.h +++ b/include/media/media-devnode.h @@ -20,9 +20,13 @@ #include #include #include +#include struct media_device; +/* debugfs top-level media directory */ +extern struct dentry *media_debugfs_root; + /* * Flag to mark the media_devnode struct as registered. Drivers must not touch * this flag directly, it will be set and cleared by media_devnode_register and diff --git a/include/media/media-request.h b/include/media/media-request.h index 6434758ab597..db0d9edfb38f 100644 --- a/include/media/media-request.h +++ b/include/media/media-request.h @@ -290,6 +290,7 @@ struct media_request_object_ops { * struct media_request_object - An opaque object that belongs to a media * request * + * @mdev: Media device this object belongs to * @ops: object's operations * @priv: object's priv pointer * @req: the request this object belongs to (can be NULL) @@ -301,6 +302,7 @@ struct media_request_object_ops { * another struct that contains the actual data for this request object. */ struct media_request_object { + struct media_device *mdev; const struct media_request_object_ops *ops; void *priv; struct media_request *req;