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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 4C275C4160E for ; Tue, 2 Mar 2021 22:55:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3405264F2D for ; Tue, 2 Mar 2021 22:55:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2360492AbhCBWVK (ORCPT ); Tue, 2 Mar 2021 17:21:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383589AbhCBVQ2 (ORCPT ); Tue, 2 Mar 2021 16:16:28 -0500 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96A3AC061794 for ; Tue, 2 Mar 2021 13:11:41 -0800 (PST) Received: by mail-qv1-xf4a.google.com with SMTP id i1so5407030qvu.12 for ; Tue, 02 Mar 2021 13:11:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=ha32Pb8LQarekc1l29yMATX3+MJye2BpgFbjrEa+47o=; b=OnY895K/7pS8uVuh5xN1WbuUXXt1LrnLrKtSlEZafXgfD7nC0rgEpXnKR7lHwkiAJV 7nD/VI4XXUOZnYpWDMKM2RNjhL5F10ODPqMqtD1A1xhi4ESH69giqc3Akw1gSu3a+rzq W/FL4ypFBsEuszLO2XsKMurKqWfPawdUJw6tBLTFNZp06Urso/TakpvkiTkh22Gf2ach jHXUGa/QvHQRntFpJKFJUZKeAe4X7RE01AWiv/grMHoQY0o3p4taXeoi0iICipsZU/fn XiVSZ5pVkWp+hBCx5PMbmfNmomEqc2vwebdVEr9Y11SlW0tjPse3q9RiAmRR9wt5fjg5 2PJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=ha32Pb8LQarekc1l29yMATX3+MJye2BpgFbjrEa+47o=; b=p7JcPYGA0w3ae++8sh3o9/Tmf+Mks4fgT5zBDLZBITCCgOPP2M1Vls3Drd2veq8TaQ M7A/1kNwLybWst2wnjn7IT4CYTNgymIsj/agzfpsphHq/UV3K4V4InS21cAc4dbRY4Bd tUBnH3w43qRk5vKJxTtAsGgabjJ/Ir+F7F8e/HrnWM/CnpO6cqyidfKsqU8d0EMHNz91 uiEF6tpPxbIkxpMi2qcdS0WLKGekC9OkPt9ozj2RAxEAJ7HUd6QmRP2qT0DzeLBMj4Q1 oH4z3Ej+IrkVkWseRcqv+w8TYFcdrpDYFbf7VEn/c/jOHmTVQwmf0BNTR+ud3caWo5Ru xkIQ== X-Gm-Message-State: AOAM533rqgQWicm8qsOYYOpFTIvw2kHdk8hplBqZx98MTqwl4iWIO3HR elb3PBsIEQxB6+ljkzQRfoLid20cXKlM1IY= X-Google-Smtp-Source: ABdhPJzTbMYKKSz5Mm8hHKRSrnzQ9BCNkd58dEhtIqC24T8TOWMdFHTwHLcwba8GIZWePxdw2QukihT9qJ4njm8= Sender: "saravanak via sendgmr" X-Received: from saravanak.san.corp.google.com ([2620:15c:2d:3:a1ad:fce1:8a40:59b6]) (user=saravanak job=sendgmr) by 2002:a05:6214:523:: with SMTP id x3mr21274886qvw.27.1614719500715; Tue, 02 Mar 2021 13:11:40 -0800 (PST) Date: Tue, 2 Mar 2021 13:11:30 -0800 In-Reply-To: <20210302211133.2244281-1-saravanak@google.com> Message-Id: <20210302211133.2244281-2-saravanak@google.com> Mime-Version: 1.0 References: <20210302211133.2244281-1-saravanak@google.com> X-Mailer: git-send-email 2.30.1.766.gb4fecdf3b7-goog Subject: [PATCH v1 1/3] driver core: Avoid pointless deferred probe attempts From: Saravana Kannan To: Greg Kroah-Hartman , "Rafael J. Wysocki" Cc: Saravana Kannan , Michael Walle , Jon Hunter , Marek Szyprowski , Geert Uytterhoeven , Guenter Roeck , kernel-team@android.com, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There's no point in adding a device to the deferred probe list if we know for sure that it doesn't have a matching driver. So, check if a device can match with a driver before adding it to the deferred probe list. Signed-off-by: Saravana Kannan --- drivers/base/dd.c | 6 ++++++ include/linux/device.h | 4 ++++ 2 files changed, 10 insertions(+) diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 9179825ff646..f18963f42e21 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -123,6 +123,9 @@ static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func); void driver_deferred_probe_add(struct device *dev) { + if (!dev->can_match) + return; + mutex_lock(&deferred_probe_mutex); if (list_empty(&dev->p->deferred_probe)) { dev_dbg(dev, "Added to deferred list\n"); @@ -726,6 +729,7 @@ static int driver_probe_device(struct device_driver *drv, struct device *dev) if (!device_is_registered(dev)) return -ENODEV; + dev->can_match = true; pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); @@ -829,6 +833,7 @@ static int __device_attach_driver(struct device_driver *drv, void *_data) return 0; } else if (ret == -EPROBE_DEFER) { dev_dbg(dev, "Device match requests probe deferral\n"); + dev->can_match = true; driver_deferred_probe_add(dev); } else if (ret < 0) { dev_dbg(dev, "Bus failed to match device: %d\n", ret); @@ -1064,6 +1069,7 @@ static int __driver_attach(struct device *dev, void *data) return 0; } else if (ret == -EPROBE_DEFER) { dev_dbg(dev, "Device match requests probe deferral\n"); + dev->can_match = true; driver_deferred_probe_add(dev); } else if (ret < 0) { dev_dbg(dev, "Bus failed to match device: %d\n", ret); diff --git a/include/linux/device.h b/include/linux/device.h index ba660731bd25..569932d282c0 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -439,6 +439,9 @@ struct dev_links_info { * @state_synced: The hardware state of this device has been synced to match * the software state of this device by calling the driver/bus * sync_state() callback. + * @can_match: The device has matched with a driver at least once or it is in + * a bus (like AMBA) which can't check for matching drivers until + * other devices probe successfully. * @dma_coherent: this particular device is dma coherent, even if the * architecture supports non-coherent devices. * @dma_ops_bypass: If set to %true then the dma_ops are bypassed for the @@ -545,6 +548,7 @@ struct device { bool offline:1; bool of_node_reused:1; bool state_synced:1; + bool can_match:1; #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) -- 2.30.1.766.gb4fecdf3b7-goog