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=-6.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 79D4EC4332B for ; Sun, 7 Mar 2021 16:03:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4C8B165107 for ; Sun, 7 Mar 2021 16:03:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231522AbhCGQCl (ORCPT ); Sun, 7 Mar 2021 11:02:41 -0500 Received: from mail.kernel.org ([198.145.29.99]:39472 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232383AbhCGQCN (ORCPT ); Sun, 7 Mar 2021 11:02:13 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9B322650FA; Sun, 7 Mar 2021 16:02:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615132932; bh=W3DWtdKbzB/Ewq0JXP5uIPr5sVdrpUWScZRv+BpwOOQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=uvTAugzrUQYpKuCcE5EB2V7uskUn7uQ1kw3Ti9BBAyqQTmqLgQKYlYnumatE5cRFc TxVpaDX8t7wop24oROmlUS96NMdVeY7PBHDIW/T3WSmx/aCPFFh9v3xHu0e6GSI/Rx ViYKo1BNlVsFC65pNKLgytdDsWIOhzT8pO1yqotAUcGPJGH0Nj83z5XIkuCh3gzRaP RCvB3K4RyMw+BKYpyVQxCNekIzPX2+xiiY9/RoaX+oINmRapsa/7H7PofVuHzmkqdE iMY49sccaS1j16kG5oQvyCvriltmludfQy+PNzABu+/0WPz+XC05tDuL+SaC1iYVBI NrHiOR3ly/7qQ== Received: by mail-oi1-f176.google.com with SMTP id x78so8416232oix.1; Sun, 07 Mar 2021 08:02:12 -0800 (PST) X-Gm-Message-State: AOAM530y6b8oPrrVJXGClw9xhwoqQGy/mg1Cjs168qlZpXpvZdilevcY QxGhW2KOMGlKtNwmvWNCSSg2hvTE1tOXKtV04i4= X-Google-Smtp-Source: ABdhPJzpPsfCCAkRmVKn193+pHQBjk17f8dkofO2rKwjX7TbuYoBS5vX7tmjl8lFu8yM18ZXMOLeGO7Q06knumxhjeE= X-Received: by 2002:aca:5e85:: with SMTP id s127mr13583208oib.67.1615132931842; Sun, 07 Mar 2021 08:02:11 -0800 (PST) MIME-Version: 1.0 References: <20210304213902.83903-1-marcan@marcan.st> <20210304213902.83903-22-marcan@marcan.st> <535ff48e-160e-4ba4-23ac-54e478a2f3ee@marcan.st> <05ccc09f-ffea-71cd-4288-beed3020bd45@marcan.st> In-Reply-To: From: Arnd Bergmann Date: Sun, 7 Mar 2021 17:01:55 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFT PATCH v3 21/27] tty: serial: samsung_tty: IRQ rework To: Krzysztof Kozlowski Cc: Hector Martin , Andy Shevchenko , linux-arm Mailing List , Marc Zyngier , Rob Herring , Olof Johansson , Mark Kettenis , Tony Lindgren , Mohamed Mediouni , Stan Skowronek , Alexander Graf , Will Deacon , Linus Walleij , Mark Rutland , Greg Kroah-Hartman , Jonathan Corbet , Catalin Marinas , Christoph Hellwig , "David S. Miller" , devicetree , "open list:SERIAL DRIVERS" , Linux Documentation List , Linux Samsung SOC , Linux-Arch , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Mar 7, 2021 at 12:34 PM Krzysztof Kozlowski wrote: > On 05/03/2021 17:29, Hector Martin wrote: > > On 06/03/2021 01.20, Andy Shevchenko wrote: > >>> I am just splitting an > >>> existing function into two, where one takes the lock and the other does > >>> the work. Do you mean using a different locking function? I'm not > >>> entirely sure what you're suggesting. > >> > >> Yes, as a prerequisite > >> > >> spin_lock_irqsave -> spin_lock(). > > > > Krzysztof, is this something you want in this series? I was trying to > > avoid logic changes to the non-Apple paths. > > I don't quite get the need for such change (the code will be still > called in interrupt handler, right?), but assuming the "why?" is > properly documented, it can be a separate patch here. This is only for readability: the common rule is to not disable interrupts when they are already disabled, so a reader might wonder if this instance of the handler is special in some case that it might be called with interrupts enabled. There is also a small overhead in accessing the global irq mask register on some architectures, but for a uart that does not make any difference of course. While I'm generally in favor of that kind of cleanup, I'd also prefer to leave it out of this series -- once you get into details like this the series gets harder to review. Arnd 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=-4.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 A2B43C433E0 for ; Sun, 7 Mar 2021 16:04:04 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 29E93650F2 for ; Sun, 7 Mar 2021 16:04:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 29E93650F2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From:In-Reply-To: References:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=wLqp8U+i3Xs1Vj5poTh//34z27Sd2MbGr0dMsqpwXP0=; b=ZpbSLBacIkHHc1dVC+n4ua1Y6 iQYUES4DM5WlMWY+xkrKMGAUuTlWdhtVuoBFV/ErX+b9algHYTP0NzS3mWjearIVq3lAqnBSKcI+Q /v658TndlF4YBCBliGnpxFdmXmNPOmZwiy538iydIsb1wkKJmntyHlXknQIvg8f3mpMq5HKJY7Y6d 1kGwYRQqybVjToF70YoC/TvPsKR/riaValcIA10qap8Ee6IcpH55WPUFvTqNZlQfUJ/PorBHd6sDr F7liTxY5uLt52GypWhJFoMLp/bsYYaTD9YsbuTvuov2lbT/OlpJcxKz6ZuGpotLa0blDY0JnQeku7 cLBA+gq+A==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lIvrM-00ArTJ-DD; Sun, 07 Mar 2021 16:02:25 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lIvrD-00ArPj-N9 for linux-arm-kernel@lists.infradead.org; Sun, 07 Mar 2021 16:02:17 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id A480065105 for ; Sun, 7 Mar 2021 16:02:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615132932; bh=W3DWtdKbzB/Ewq0JXP5uIPr5sVdrpUWScZRv+BpwOOQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=uvTAugzrUQYpKuCcE5EB2V7uskUn7uQ1kw3Ti9BBAyqQTmqLgQKYlYnumatE5cRFc TxVpaDX8t7wop24oROmlUS96NMdVeY7PBHDIW/T3WSmx/aCPFFh9v3xHu0e6GSI/Rx ViYKo1BNlVsFC65pNKLgytdDsWIOhzT8pO1yqotAUcGPJGH0Nj83z5XIkuCh3gzRaP RCvB3K4RyMw+BKYpyVQxCNekIzPX2+xiiY9/RoaX+oINmRapsa/7H7PofVuHzmkqdE iMY49sccaS1j16kG5oQvyCvriltmludfQy+PNzABu+/0WPz+XC05tDuL+SaC1iYVBI NrHiOR3ly/7qQ== Received: by mail-oi1-f177.google.com with SMTP id j1so8397340oiw.3 for ; Sun, 07 Mar 2021 08:02:12 -0800 (PST) X-Gm-Message-State: AOAM531ycXmbJEKlPqSCYJRfNMHiBcX9vHxNkNiVj5PQwXwSWFKTN8Bw a8sS9/8I+Fbf4HPhsPvtqI8D5rNIRXGIdWquz7c= X-Google-Smtp-Source: ABdhPJzpPsfCCAkRmVKn193+pHQBjk17f8dkofO2rKwjX7TbuYoBS5vX7tmjl8lFu8yM18ZXMOLeGO7Q06knumxhjeE= X-Received: by 2002:aca:5e85:: with SMTP id s127mr13583208oib.67.1615132931842; Sun, 07 Mar 2021 08:02:11 -0800 (PST) MIME-Version: 1.0 References: <20210304213902.83903-1-marcan@marcan.st> <20210304213902.83903-22-marcan@marcan.st> <535ff48e-160e-4ba4-23ac-54e478a2f3ee@marcan.st> <05ccc09f-ffea-71cd-4288-beed3020bd45@marcan.st> In-Reply-To: From: Arnd Bergmann Date: Sun, 7 Mar 2021 17:01:55 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFT PATCH v3 21/27] tty: serial: samsung_tty: IRQ rework To: Krzysztof Kozlowski Cc: Hector Martin , Andy Shevchenko , linux-arm Mailing List , Marc Zyngier , Rob Herring , Olof Johansson , Mark Kettenis , Tony Lindgren , Mohamed Mediouni , Stan Skowronek , Alexander Graf , Will Deacon , Linus Walleij , Mark Rutland , Greg Kroah-Hartman , Jonathan Corbet , Catalin Marinas , Christoph Hellwig , "David S. Miller" , devicetree , "open list:SERIAL DRIVERS" , Linux Documentation List , Linux Samsung SOC , Linux-Arch , Linux Kernel Mailing List X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210307_160216_231247_FD1B8166 X-CRM114-Status: GOOD ( 20.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, Mar 7, 2021 at 12:34 PM Krzysztof Kozlowski wrote: > On 05/03/2021 17:29, Hector Martin wrote: > > On 06/03/2021 01.20, Andy Shevchenko wrote: > >>> I am just splitting an > >>> existing function into two, where one takes the lock and the other does > >>> the work. Do you mean using a different locking function? I'm not > >>> entirely sure what you're suggesting. > >> > >> Yes, as a prerequisite > >> > >> spin_lock_irqsave -> spin_lock(). > > > > Krzysztof, is this something you want in this series? I was trying to > > avoid logic changes to the non-Apple paths. > > I don't quite get the need for such change (the code will be still > called in interrupt handler, right?), but assuming the "why?" is > properly documented, it can be a separate patch here. This is only for readability: the common rule is to not disable interrupts when they are already disabled, so a reader might wonder if this instance of the handler is special in some case that it might be called with interrupts enabled. There is also a small overhead in accessing the global irq mask register on some architectures, but for a uart that does not make any difference of course. While I'm generally in favor of that kind of cleanup, I'd also prefer to leave it out of this series -- once you get into details like this the series gets harder to review. Arnd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel