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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 91A38C433EF for ; Sat, 16 Apr 2022 15:49:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232120AbiDPPvz (ORCPT ); Sat, 16 Apr 2022 11:51:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230108AbiDPPvx (ORCPT ); Sat, 16 Apr 2022 11:51:53 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 0FC095D1AE for ; Sat, 16 Apr 2022 08:49:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1650124161; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=T6tJt5xi4j/95RjrkCYGghk3+Qa3IFPUrOmUFpGR2eM=; b=C9U/rRLF7tusDSlakjk71gA64LIbz0o6oD3bnzYp1GJHnP2hKzdfoRrSIzzp7zzEyDiw61 oyvo77BlGb+ORow/T4OXj+o0uQ7c5amqNlBiDjnTiO/fb+drgVrimQJjMoUddn02CldyoN F3ZN7vv/9CYkfl+ISScPqJNBx6uEUMc= Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-413-PaGu8qmuP4SFaYgHHFWftQ-1; Sat, 16 Apr 2022 11:49:17 -0400 X-MC-Unique: PaGu8qmuP4SFaYgHHFWftQ-1 Received: by mail-qk1-f198.google.com with SMTP id m23-20020a05620a221700b006809e1fa4fdso7372972qkh.6 for ; Sat, 16 Apr 2022 08:49:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=T6tJt5xi4j/95RjrkCYGghk3+Qa3IFPUrOmUFpGR2eM=; b=7UfFnlqw+00hG1Xs41wLmMZC80IEvFy5RmWpVx9v4FzIC33LokmSkTq3rBW2XVcJ9E RuZnKOi5xAY0VRK0sx+/raOt8IeOqW2HMj29rJgofkLknxhYPqjWbNdSgVwKViZoIlZL Jwq9KGzF3WSXF00OSk9PlyVEdOT9bvPnMsDzh2FdncfMc2KGHUw4sqZSRY6yNc9N7l9Y iaHiio7CJD62bMTBMtWwiBdTlTJgjHE6fUKZc5ANebwSLHvvWehYZjJvuaRNygs8DQYX gDSBGZ9EeVVMgOB0BHKHU9cZ5j/h1sRGahI2jvL5F0egoMtIi2yL5ZaY+sZZ/wcW1nDp aIGQ== X-Gm-Message-State: AOAM531tPZl1tBJ5Y3Wd5j7RV0fHf/Ihxui+AMTo1dnQH32xvl53n9W9 DAvOgWypOqxO0pUDtLsZChgerSrUy9GT7KYTyQe6D/+vbFIwksAylO9b0tPtGuWAVlbIyvWyJvl wjY+xNToqmB2lCFLM9CUeggcD X-Received: by 2002:a37:510:0:b0:69e:8868:c691 with SMTP id 16-20020a370510000000b0069e8868c691mr231640qkf.731.1650124157113; Sat, 16 Apr 2022 08:49:17 -0700 (PDT) X-Google-Smtp-Source: ABdhPJx7eBSX9BoYG86DDTIzi+DQA4SCrsjCtidPwA9Fiv/mUYye57Js4SZZMzHh5S5PV6hbXJnvKQ== X-Received: by 2002:a37:510:0:b0:69e:8868:c691 with SMTP id 16-20020a370510000000b0069e8868c691mr231634qkf.731.1650124156904; Sat, 16 Apr 2022 08:49:16 -0700 (PDT) Received: from localhost.localdomain (024-205-208-113.res.spectrum.com. [24.205.208.113]) by smtp.gmail.com with ESMTPSA id i62-20020a37b841000000b0069c10d27571sm3935699qkf.70.2022.04.16.08.49.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 16 Apr 2022 08:49:16 -0700 (PDT) Subject: Re: [PATCH] spi: remove spin_lock_irq in the irq procress To: =?UTF-8?B?6YOt5Yqb6LGq?= Cc: Mark Brown , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?B?5ZGC6Iqz6aiwTHVXZWxscw==?= , "lh.kuo" , nathan@kernel.org References: <9e12d806c5554b4ed18c644f71f6662fcf0d0516.1649813822.git.lhjeff911@gmail.com> From: Tom Rix Message-ID: Date: Sat, 16 Apr 2022 08:49:13 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/14/22 6:16 AM, 郭力豪 wrote: > Hi Tom : > > This SPI driver only handles one transfer at a time. > That's why locks are not needed. Please add this statement to the commit log. In a commit log, not only do I look for what was changed but also why the change was made. Tom > > > Li-hao Kuo > > Tom Rix 於 2022年4月13日 週三 下午7:45寫道： >> >> On 4/12/22 6:38 PM, Li-hao Kuo wrote: >>> - remove spin_lock_irq and spin_unlock_irq in the irq funciton >> function >> >> I was expecting a statement on why is the lock is not needed. >> >> Could you add one ? >> >> Tom >> >>> Signed-off-by: Li-hao Kuo >>> --- >>> drivers/spi/spi-sunplus-sp7021.c | 4 +--- >>> 1 file changed, 1 insertion(+), 3 deletions(-) >>> >>> diff --git a/drivers/spi/spi-sunplus-sp7021.c b/drivers/spi/spi-sunplus-sp7021.c >>> index f989f7b..120623c 100644 >>> --- a/drivers/spi/spi-sunplus-sp7021.c >>> +++ b/drivers/spi/spi-sunplus-sp7021.c >>> @@ -199,8 +199,6 @@ static irqreturn_t sp7021_spi_master_irq(int irq, void *dev) >>> if (tx_len == 0 && total_len == 0) >>> return IRQ_NONE; >>> >>> - spin_lock_irq(&pspim->lock); >>> - >>> rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status); >>> if (fd_status & SP7021_RX_FULL_FLAG) >>> rx_cnt = pspim->data_unit; >>> @@ -239,7 +237,7 @@ static irqreturn_t sp7021_spi_master_irq(int irq, void *dev) >>> >>> if (isrdone) >>> complete(&pspim->isr_done); >>> - spin_unlock_irq(&pspim->lock); >>> + >>> return IRQ_HANDLED; >>> } >>>