From patchwork Sat Jul 16 08:05:02 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaktipriya Shridhar X-Patchwork-Id: 9233053 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C679B608A7 for ; Sat, 16 Jul 2016 08:05:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B99A223861 for ; Sat, 16 Jul 2016 08:05:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ABD4524DA2; Sat, 16 Jul 2016 08:05:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4A63B23861 for ; Sat, 16 Jul 2016 08:05:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751471AbcGPIFX (ORCPT ); Sat, 16 Jul 2016 04:05:23 -0400 Received: from mail-pf0-f196.google.com ([209.85.192.196]:35079 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751470AbcGPIFG (ORCPT ); Sat, 16 Jul 2016 04:05:06 -0400 Received: by mail-pf0-f196.google.com with SMTP id t190so7711894pfb.2; Sat, 16 Jul 2016 01:05:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=lzzJDtPP8tUBOl/oeCXoQdI9BGHROtdjNxW+9L8Pwd0=; b=cdATxS9GOdFtb3Yo7zZutFAxLYbwofaruwmLh4ObKKhix+AFpY0AzxWNU3+fCQZZWg 4BajWJa804cCRitMwlXm6SGo/51zt4umCNIlEWVGE3fL1v2n5oZjY/lRBzqy9nExBRWC cd2fPJlzBsbjSkzlK3LFeZ7dhQ2UmGcrpuARuIVB61fWSqzbyfzV3Na7dASrNmTEkBFK RWln5x3LOCFgkqB381/0mZ+ONFS/T7TU1QiAzue9CvnnUbBoNwyg2EXI32ZbbxRFCl+l xoLkhdpmBeQ1S4O0w/RDN9EKmMsk5cVVe2XpPqGfx8krQCxkPosCmHVrxmF7ZVn+fVRV tECQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=lzzJDtPP8tUBOl/oeCXoQdI9BGHROtdjNxW+9L8Pwd0=; b=hZmEU98mALLdDJSH61KUG1cVwxs+EAhBCSoblbpmiICGqb93vw+8fWOrOAuNYPJ+1u fLgy6oRXxBJPvsSDWkhoK2YflpROkTAWGFdk7JNxsHU+1JoVuyRUo0oBcj5c8Hp1MqfD A7uXX7K5WZF8C6HRdUP75rb0gKqxHQrgH7e/SestNAQCROt6XvjGT913rIwt8eb+DE5n 0MMcRJvaMMDvAjguX3q1oM9XbraZVGXjBpvIZdPrSwRafUaYxIySURAZCFK2l+rDiZxk 2v4f8MHcPS0931SPmukLDjJTiUC4/G5W9JQSsRcLWKQjL7J8STdOUqq1TZsQDJdI7GgR T7hg== X-Gm-Message-State: ALyK8tI/bUWujV9GsudsXRRNkLBS2VmtqTapHLrFDWQ5+v7RNvxThFBibz2EegtQrgYztw== X-Received: by 10.98.8.13 with SMTP id c13mr28633536pfd.166.1468656305567; Sat, 16 Jul 2016 01:05:05 -0700 (PDT) Received: from Karyakshetra ([2401:fa00:c:fd01:e18f:1a:cff1:2c2]) by smtp.gmail.com with ESMTPSA id xl1sm2100421pab.8.2016.07.16.01.05.04 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sat, 16 Jul 2016 01:05:05 -0700 (PDT) Date: Sat, 16 Jul 2016 13:35:02 +0530 From: Bhaktipriya Shridhar To: Mark Brown Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, Tejun Heo Subject: [PATCH] spi: spi-sh: Remove deprecated create_singlethread_workqueue Message-ID: <20160716080502.GA4700@Karyakshetra> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The workqueue has a single workitem(&ss->ws) and hence doesn't require ordering. Also, it is not being used on a memory reclaim path. Hence, the singlethreaded workqueue has been replaced with the use of system_wq. System workqueues have been able to handle high level of concurrency for a long time now and hence it's not required to have a singlethreaded workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue created with create_singlethread_workqueue(), system_wq allows multiple work items to overlap executions even on the same CPU; however, a per-cpu workqueue doesn't have any CPU locality or global ordering guarantee unless the target CPU is explicitly specified and thus the increase of local concurrency shouldn't make any difference. Work item has been flushed in spi_sh_remove() to ensure that there are no pending tasks while disconnecting the driver. Signed-off-by: Bhaktipriya Shridhar --- drivers/spi/spi-sh.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/spi/spi-sh.c b/drivers/spi/spi-sh.c index 5025011..2bf53f0 100644 --- a/drivers/spi/spi-sh.c +++ b/drivers/spi/spi-sh.c @@ -82,7 +82,6 @@ struct spi_sh_data { int irq; struct spi_master *master; struct list_head queue; - struct workqueue_struct *workqueue; struct work_struct ws; unsigned long cr1; wait_queue_head_t wait; @@ -380,7 +379,7 @@ static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg) spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1); list_add_tail(&mesg->queue, &ss->queue); - queue_work(ss->workqueue, &ss->ws); + schedule_work(&ss->ws); spin_unlock_irqrestore(&ss->lock, flags); @@ -425,7 +424,7 @@ static int spi_sh_remove(struct platform_device *pdev) struct spi_sh_data *ss = platform_get_drvdata(pdev); spi_unregister_master(ss->master); - destroy_workqueue(ss->workqueue); + flush_work(&ss->ws); free_irq(ss->irq, ss); return 0; @@ -484,18 +483,11 @@ static int spi_sh_probe(struct platform_device *pdev) spin_lock_init(&ss->lock); INIT_WORK(&ss->ws, spi_sh_work); init_waitqueue_head(&ss->wait); - ss->workqueue = create_singlethread_workqueue( - dev_name(master->dev.parent)); - if (ss->workqueue == NULL) { - dev_err(&pdev->dev, "create workqueue error\n"); - ret = -EBUSY; - goto error1; - } ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss); if (ret < 0) { dev_err(&pdev->dev, "request_irq error\n"); - goto error2; + goto error1; } master->num_chipselect = 2; @@ -514,8 +506,6 @@ static int spi_sh_probe(struct platform_device *pdev) error3: free_irq(irq, ss); - error2: - destroy_workqueue(ss->workqueue); error1: spi_master_put(master);