Received: by 10.223.176.46 with SMTP id f43csp2279172wra; Thu, 25 Jan 2018 07:33:18 -0800 (PST) X-Google-Smtp-Source: AH8x224xDXXv2JtEpg6qzDeiM6zUfdBN+IXY1Q7ZHigDCj6YCHh/D/zsC2Cucr/LZNq/P1ql41w1 X-Received: by 2002:a17:902:b783:: with SMTP id e3-v6mr11879648pls.160.1516894398507; Thu, 25 Jan 2018 07:33:18 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1516894398; cv=none; d=google.com; s=arc-20160816; b=qI3hwlhyKkiTdtWunq5TniKc86eQjl3RTOYCcvDLijRk4Pr7ixCPJhsdyEtEVjJlMQ LJG8NYE5zXScllqLLBN61bjRHNyyxOiRluux+YJAAF/GnVcLD2J6xblwZsiGhLqmLxO5 rD4Ni7UFy/urRsSY5exof2CILjKbfu1LERLUsboGxYtAj2i0SXPSaW/cRrlhJMygCL8G WxDGcW+jay+t36rFui1XmgLfvSB+ueNF2ZbQXXvvzj6nngwE3gVjPolmkJZUaEo844Ab fYiJKqba4NaFOvxIs36gf5ZEJ/1nzRS47J2NjT0PCd1aRsWSrisvcTEw7HxYjqLCYFpT KaSA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:dkim-signature:arc-authentication-results; bh=MVkIYkvCp0BTc1wn3d6I/0UCNR6tNg8LLEk2zddJLG8=; b=KfWflsyN9jDRHcyszTihHsjl0idHHVb8ZavZlqFvK7R6JlpH3Owlkf7hctOE7IhsMI XuGXac28ynWnXIJmcB7f+81JhHqUHvEJAa6a2SyIYBeBgD6RzsmZs2cnY6kx+JdwdJvO sFD2JPOL98bkjuCsfVcG4kuMcFfi50vRLRN0ruBhoqLB4Qp+hNarlrNvx1NmvI0GiX+i 25DWuE5BdL6It62vAbONbJEfMnAy7gU5p59vld3rhgaXPM7a1UJGNTqlVjxbyYbTG5Ry VgqmdG9q4YZ47Yl6NSUF+McOgsCwD1jvJs72eVzp3pbkU5SSizyM2HqB+H648YHq5Rtf YXnw== ARC-Authentication-Results: i=1; mx.google.com; dkim=fail header.i=@gmail.com header.s=20161025 header.b=j+ONeVnq; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id j10si4769634pfe.133.2018.01.25.07.33.04; Thu, 25 Jan 2018 07:33:18 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@gmail.com header.s=20161025 header.b=j+ONeVnq; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751240AbeAYPaW (ORCPT + 99 others); Thu, 25 Jan 2018 10:30:22 -0500 Received: from mail-qt0-f193.google.com ([209.85.216.193]:42488 "EHLO mail-qt0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750769AbeAYPaU (ORCPT ); Thu, 25 Jan 2018 10:30:20 -0500 Received: by mail-qt0-f193.google.com with SMTP id c2so20075880qtn.9; Thu, 25 Jan 2018 07:30:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=MVkIYkvCp0BTc1wn3d6I/0UCNR6tNg8LLEk2zddJLG8=; b=j+ONeVnqjCv+ZgxQnRw5uTxbMQNAjTKCVkyX3c6lgIcR41M4AQh59CUGK/jxLbffCU Fh8q4ZThY2cYMFl0eMe/9WLvmIH9bK3mzMyno5ku8+0ogKpt3H7WNRf/+nEabs3Ac3mm UPwGYmK0u591cekNYpl7ZAQx9VlvpNdQcnYcU3++RwL7zXE4SczdbzBLYgql2M1TxJIJ U9eJ39hmiNg8wUK6Rs1GIoG1tieogH8UYbQG+/7GpfXU7tTQTW9WdW6ekZrKSgotOnMK EqU9efc69xiE8Co1w4EJarhxMyNMXopxKWAQVXzi6D4L5UtzDVP15xgMx70kSI/ung1H njww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=MVkIYkvCp0BTc1wn3d6I/0UCNR6tNg8LLEk2zddJLG8=; b=o/ERfZRXrNb5Qxcq26ozx7IKkKsnW/c/G1d8iAuy1w2pQj3JsThuzKscrfx/s7SXtN IVKgPm+9AYYIcLgs3mR6vC1DRNNkyxAL5w5iipIRh7CslOP5KkiLB3ck2qejqzcNlqPw MQ1Qfk2beFBJwonKiEoWAtT4K7cSzCL3jbMux1hH6Qzyyr7+1o2WeKcntLMjZb7ZIGw8 RQsvoamD3/+CUHuo1veIclQ1cvG5x+eFJGdugOxod/8dV/lz2CUn2lqoAZ+IzvXCc6Oq H6Ob4USW64TjECDfDILffeKTKO+PmOhRq2SP/6ZiqM33m/IJyyD7139E5wUcXfBXJxBd acCg== X-Gm-Message-State: AKwxytd6L9D6zsUwn+wo7FXt/J1MEgDP5dK9sN/ZXkKovLs13iDDeOKe 8XBiNuF5II5TC/JIoyNO+5msyvQH X-Received: by 10.200.16.141 with SMTP id a13mr443392qtj.65.1516894218844; Thu, 25 Jan 2018 07:30:18 -0800 (PST) Received: from localhost (dhcp-ec-8-6b-ed-7a-cf.cpe.echoes.net. [72.28.5.223]) by smtp.gmail.com with ESMTPSA id t87sm392673qkl.34.2018.01.25.07.30.18 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 25 Jan 2018 07:30:18 -0800 (PST) Date: Thu, 25 Jan 2018 07:30:00 -0800 From: Tejun Heo To: Jia-Ju Bai Cc: mlord@pobox.com, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] ata: sata_mv: Replace mdelay with usleep_range in mv_reset_channel Message-ID: <20180125153000.GD17457@devbig577.frc2.facebook.com> References: <1516876013-12653-1-git-send-email-baijiaju1990@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1516876013-12653-1-git-send-email-baijiaju1990@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 25, 2018 at 06:26:52PM +0800, Jia-Ju Bai wrote: > After checking all possible call chains to mv_reset_channel here, > my tool finds that mv_reset_channel is never called in atomic context, > namely never in an interrupt handler or holding a spinlock. > Thus mdelay can be replaced with usleep_range to avoid busy wait. > > This is found by a static analysis tool named DCNS written by myself. > > Signed-off-by: Jia-Ju Bai Applied to libata/for-4.16. Thanks. -- tejun