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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 01F8BC3A5A7 for ; Mon, 2 Sep 2019 21:08:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD2B822DBF for ; Mon, 2 Sep 2019 21:08:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567458501; bh=s9W7m9n2kMALyK7KmGbZwDquYZXEzWR6eyYkv2dm2f8=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=FwCnv90xc+a33ttr/SYkJZwuTQOoZtIMOmQSSUicGoNBK00habsqjH6XYNPLqzDR/ XDOiYSkqlPh/vWxmWGauwNNRyJRYdWOM5kuWaHmWISZjXVIdKUulB+KD4aCqTU5gMK CrR1T8gJpfWK2vBmnPMG7nqSgyPumD9dM9T3ZyI0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727522AbfIBVIV (ORCPT ); Mon, 2 Sep 2019 17:08:21 -0400 Received: from mail-ot1-f67.google.com ([209.85.210.67]:35669 "EHLO mail-ot1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726964AbfIBVIU (ORCPT ); Mon, 2 Sep 2019 17:08:20 -0400 Received: by mail-ot1-f67.google.com with SMTP id 100so14719013otn.2; Mon, 02 Sep 2019 14:08:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=huTQD+G6wSs8hXbu4stIdO9xW+9jjAIMQ/j2IBKOSLs=; b=kGdy5a6AxvT29kVSZ2Kida0dWzlyvLm2AgBkZrYN9pf7HnDv9MfF345a+0CKCigvWF CL1bNb8UEGH3t3ws7yGOul2dULhL3pS7ar+AiP3+x0p4oDRTngpwPOv5IVz+/CYiJOAx fY2Z2JUgCvs7HiQLDLSzMlBEBK95cG2gt3OnQMP7a+8sKU3vnvPuHS3UgzW9c1X/vNSd Bi39o+TKfx1+fltm4JGm3yZ7OzMo0B9K8L5AKm2mgYZ3AA2+IH2BYHP7Xz7Jk+eax+dK 0w6g7FSG38HxRssA7lEMRA4o6cpBpZs28wKiYpZO/wM787ILchCaQJ805OuTghwHzvMn wacw== X-Gm-Message-State: APjAAAXLxzdB5swd05MTJqInq8SQCSgIM3hFSrkFATmawv8Ny7j+qTog UhN1UZ2SdtbwqCCK9ZGINA4xg6364tcjiaMojAI= X-Google-Smtp-Source: APXvYqyI27hb2RWcNRadfCbRlDtIXktARg70zP5FAIcXUKIjdX66KnAXJFj+Kt7ssn8uG1C93zycuqAbTk3HFoTJ7d8= X-Received: by 2002:a05:6830:154:: with SMTP id j20mr26200025otp.266.1567458499533; Mon, 02 Sep 2019 14:08:19 -0700 (PDT) MIME-Version: 1.0 References: <20190722023530.67676-1-skunberg.kelsey@gmail.com> <20190722023530.67676-2-skunberg.kelsey@gmail.com> <20190722182929.GA203187@google.com> In-Reply-To: <20190722182929.GA203187@google.com> From: "Rafael J. Wysocki" Date: Mon, 2 Sep 2019 23:08:08 +0200 Message-ID: Subject: Re: [PATCH 1/3] ACPI: Remove acpi_has_method() call from acpi_adxl.c To: Bjorn Helgaas Cc: "Rafael J. Wysocki" , Kelsey Skunberg , "Rafael J. Wysocki" , Len Brown , ACPI Devel Mailing List , Linux Kernel Mailing List , skhan@linuxfoundation.org, linux-kernel-mentees@lists.linuxfoundation.org, bjorn@helgaas.com, Tony Luck , Borislav Petkov Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sorry for the delayed reply. On Mon, Jul 22, 2019 at 8:29 PM Bjorn Helgaas wrote: > > [+cc Tony (original author), Borislav (merged original patch)] > > On Mon, Jul 22, 2019 at 10:31:11AM +0200, Rafael J. Wysocki wrote: > > On Mon, Jul 22, 2019 at 4:36 AM Kelsey Skunberg > > wrote: > > > > > > acpi_check_dsm() will already return an error if the DSM method does not > > > exist. Checking if the DSM method exists before the acpi_check_dsm() call > > > is not needed. Remove acpi_has_method() call to avoid additional work. > > > > > > Signed-off-by: Kelsey Skunberg > > > --- > > > drivers/acpi/acpi_adxl.c | 5 ----- > > > 1 file changed, 5 deletions(-) > > > > > > diff --git a/drivers/acpi/acpi_adxl.c b/drivers/acpi/acpi_adxl.c > > > index 13c8f7b50c46..89aac15663fd 100644 > > > --- a/drivers/acpi/acpi_adxl.c > > > +++ b/drivers/acpi/acpi_adxl.c > > > @@ -148,11 +148,6 @@ static int __init adxl_init(void) > > > return -ENODEV; > > > } > > > > > > - if (!acpi_has_method(handle, "_DSM")) { > > > - pr_info("No DSM method\n"); > > > > And why is printing the message not useful? > > > > > - return -ENODEV; > > > - } > > > - > > > if (!acpi_check_dsm(handle, &adxl_guid, ADXL_REVISION, > > > ADXL_IDX_GET_ADDR_PARAMS | > > > ADXL_IDX_FORWARD_TRANSLATE)) { > > The next line of context (not included in the patch): > > pr_info("DSM method does not support forward translate\n"); > > IMHO kernel messages that are just a constant string, with no context > or variable part (device ID, path, error code, etc) are questionable > in general. Is there any dev_printk()-like thing that takes an > acpi_handle? Seems like that would be useful for cases like this. > > This message *does* include an "ADXL: " prefix (from the pr_fmt > definition), and from reading the code you can see that the only > possible method is "\_SB.ADXL._DSM". > > There's nothing an end user can do with these messages, so I suspect > their value is for debugging during platform bringup, and it would be > sufficient to drop the first one (as Kelsey's patch does) and change > the second one like this: > > - pr_info("DSM method does not support forward translate\n"); > + pr_info("%s DSM missing or does not support forward translate\n", > + path); You have a point, but then I would expect the changelog to mention that. As it stands, the patch does more than the changelog says, which isn't nice.