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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 C739EC5AE5E for ; Tue, 19 Jun 2018 20:59:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 86BA220661 for ; Tue, 19 Jun 2018 20:59:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 86BA220661 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030578AbeFSU7W (ORCPT ); Tue, 19 Jun 2018 16:59:22 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:50389 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030301AbeFSU7S (ORCPT ); Tue, 19 Jun 2018 16:59:18 -0400 Received: by mail-wm0-f65.google.com with SMTP id e16-v6so2544110wmd.0 for ; Tue, 19 Jun 2018 13:59:18 -0700 (PDT) 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; bh=mjYHSJbe8beWgs7as0mUAtGZ5vsVj/kppDBdnF8dUmI=; b=OFvm4TzSse2NSVGTgEBKuxL2JXikTVUg6zkYBXa1szPPbVHEtMCQCvN2PW6EMnrTLi 4qCM7hVoqaVZgIKZhZQJS3kLdbF8ZswO9Z+ZOiUeG5RiEWWcbA/dIn1CllOf7tJkv1Ox w4nfeaPXAUlfvUkChCSAk5D0LZJt66a1PUyvm/VzSdo+D4nJ6vyTYT2m9STC1Q2vwtZO MoZ2A8+slI2x3z87yVjlMvFMgULmeXZc8OB9NYLC1z3lwHdjGrAu1R0yqou28jHq/qFe c5zBG+oE8jcquwh03Ee/J+ugLtEwoHL0CBl6VSCvuF7uAi9jUDQfcbY6bNckj4uVqNNF b8uw== X-Gm-Message-State: APt69E0Rrmg2KnhxjcQKE9SPYrGaM6ZKuIYzGWg+LjftBbCexr4jpChL THipd0iYvKytTyePDmqXF78KbDfkoTY= X-Google-Smtp-Source: ADUXVKJ3OddB2fw0ENv1n/k8NWIPeHLJANU2ErgZVkLXbFPXuNs8VpSlklkchMv0fKfj/h5hyQs85g== X-Received: by 2002:a1c:e6d9:: with SMTP id e86-v6mr12002302wmi.135.1529441957190; Tue, 19 Jun 2018 13:59:17 -0700 (PDT) Received: from minerva.home ([90.77.100.34]) by smtp.gmail.com with ESMTPSA id k17-v6sm1431150wmc.23.2018.06.19.13.59.15 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 19 Jun 2018 13:59:16 -0700 (PDT) From: Javier Martinez Canillas To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Mark Brown , Tomeu Vizoso , Andy Shevchenko , Rob Herring , Javier Martinez Canillas , Greg Kroah-Hartman Subject: [PATCH] driver core: add a debugfs entry to show deferred devices Date: Tue, 19 Jun 2018 22:59:14 +0200 Message-Id: <20180619205914.21375-1-javierm@redhat.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For debugging purposes it may be useful to know what are the devices whose probe function was deferred. Add a debugfs entry showing that information. $ cat /sys/kernel/debug/deferred_devices 48070000.i2c:twl@48:bci musb-hdrc.0.auto omapdrm.0 Signed-off-by: Javier Martinez Canillas --- Changes since RFC v1: - Remove unneeded ret variable from deferred_devs_show() Changes since RFC v2: - Use DEFINE_SHOW_ATTRIBUTE() macro. - Don't propagate debugfs_create_file() error. - Remove IS_ENABLED(CONFIG_DEBUG_FS) guards. - Drop RFC prefix. drivers/base/dd.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 1435d7281c6..8ec9e3cfbe4 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -16,6 +16,7 @@ * Copyright (c) 2007-2009 Novell Inc. */ +#include #include #include #include @@ -224,6 +225,24 @@ void device_unblock_probing(void) driver_deferred_probe_trigger(); } +/* + * deferred_devs_show() - Show the devices in the deferred probe pending list. + */ +static int deferred_devs_show(struct seq_file *s, void *data) +{ + struct device_private *curr; + + mutex_lock(&deferred_probe_mutex); + + list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe) + seq_printf(s, "%s\n", dev_name(curr->device)); + + mutex_unlock(&deferred_probe_mutex); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(deferred_devs); + /** * deferred_probe_initcall() - Enable probing of deferred devices * @@ -233,6 +252,9 @@ void device_unblock_probing(void) */ static int deferred_probe_initcall(void) { + debugfs_create_file("deferred_devices", 0444, NULL, NULL, + &deferred_devs_fops); + driver_deferred_probe_enable = true; driver_deferred_probe_trigger(); /* Sort as many dependencies as possible before exiting initcalls */ -- 2.17.1