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 15674C433F5 for ; Wed, 27 Apr 2022 15:44:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240106AbiD0PsD (ORCPT ); Wed, 27 Apr 2022 11:48:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240120AbiD0PsC (ORCPT ); Wed, 27 Apr 2022 11:48:02 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 914CD4EA30; Wed, 27 Apr 2022 08:44:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1651074287; x=1682610287; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=VeXWrrau3UGYgT+PE4NxfpOWIgpbbEl5MsiQ9g95Uas=; b=RDm++GYGo3zeL/S+3XOTfVA3GZGVgz3OI9fwiyoeyfQ1UEddFCEQmEHH lywUQcBy5pdO0hd1K8GnBwkIFM6ITHPK27o1h2lQR4yUCLi141/2Iuny4 dPerzjxzcQpgl554653PHRlKZiky3cz3jvtqCih/U1Hgh/VckzL5Np3Qz KZsqrzKiinhdPyTX7pnN7vlXqIa+SRdR2Di14xVQpDhBGcpv68p0LOosJ 8jBx7Y098Y8VdzMqi/SvTxqxIBidzIE53d29pzaaC4fp4tyA012sOESmx 9znifIGvtcs2hV9U8GRO7zeBSfANA9q2BTuo+k5s7nGTCLr/DYiFIMZ/R g==; X-IronPort-AV: E=McAfee;i="6400,9594,10330"; a="352403846" X-IronPort-AV: E=Sophos;i="5.90,293,1643702400"; d="scan'208";a="352403846" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Apr 2022 08:20:14 -0700 X-IronPort-AV: E=Sophos;i="5.90,293,1643702400"; d="scan'208";a="705592999" Received: from eaojeh-mobl1.amr.corp.intel.com (HELO [10.212.22.124]) ([10.212.22.124]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Apr 2022 08:20:12 -0700 Message-ID: Date: Wed, 27 Apr 2022 08:20:11 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [RFC 1/1] drivers/dma/*: replace tasklets with workqueue Content-Language: en-US To: Vinod Koul , Allen Pais Cc: olivier.dautricourt@orolia.com, sr@denx.de, keescook@chromium.org, linux-hardening@vger.kernel.org, ludovic.desroches@microchip.com, tudor.ambarus@microchip.com, f.fainelli@gmail.com, rjui@broadcom.com, sbranden@broadcom.com, bcm-kernel-feedback-list@broadcom.com, nsaenz@kernel.org, paul@crapouillou.net, Eugeniy.Paltsev@synopsys.com, gustavo.pimentel@synopsys.com, vireshk@kernel.org, andriy.shevchenko@linux.intel.com, leoyang.li@nxp.com, zw@zh-kernel.org, wangzhou1@hisilicon.com, shawnguo@kernel.org, s.hauer@pengutronix.de, sean.wang@mediatek.com, matthias.bgg@gmail.com, afaerber@suse.de, mani@kernel.org, logang@deltatee.com, sanju.mehta@amd.com, daniel@zonque.org, haojian.zhuang@gmail.com, robert.jarzmik@free.fr, agross@kernel.org, bjorn.andersson@linaro.org, krzysztof.kozlowski@linaro.org, green.wan@sifive.com, orsonzhai@gmail.com, baolin.wang7@gmail.com, zhang.lyra@gmail.com, patrice.chotard@foss.st.com, linus.walleij@linaro.org, wens@csie.org, jernej.skrabec@gmail.com, samuel@sholland.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220419211658.11403-1-apais@linux.microsoft.com> <20220419211658.11403-2-apais@linux.microsoft.com> From: Dave Jiang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 4/26/2022 7:45 PM, Vinod Koul wrote: > On 19-04-22, 21:16, Allen Pais wrote: >> The tasklet is an old API which will be deprecated, workqueue API >> cab be used instead of them. > What is the reason for tasklet removal, I am not sure old is a reason to > remove an API... > >> This patch replaces the tasklet usage in drivers/dma/* with a >> simple work. > Dmaengines need very high throughput, one of the reasons in dmaengine > API design to use tasklet was higher priority given to them. Will the > workqueue allow that...? Wouldn't the logical move be to convert threaded irq IF tasklets are being deprecated rather than using workqueue as replacement? Also, wouldn't all the spin_lock_bh() calls need to be changed to spin_lock_irqsave() now? Probably not as simple as just replace tasklet with workqueue.