From patchwork Sat Jul 2 08:45:10 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaktipriya Shridhar X-Patchwork-Id: 9210757 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 B6B5160752 for ; Sat, 2 Jul 2016 08:45:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A47271FEBD for ; Sat, 2 Jul 2016 08:45:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9512A286CE; Sat, 2 Jul 2016 08:45:17 +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 241011FEBD for ; Sat, 2 Jul 2016 08:45:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751838AbcGBIpQ (ORCPT ); Sat, 2 Jul 2016 04:45:16 -0400 Received: from mail-pa0-f68.google.com ([209.85.220.68]:34525 "EHLO mail-pa0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751324AbcGBIpO (ORCPT ); Sat, 2 Jul 2016 04:45:14 -0400 Received: by mail-pa0-f68.google.com with SMTP id us13so11533702pab.1; Sat, 02 Jul 2016 01:45:14 -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=1BIBOrEM4Q+ZyScf7kriiN6H/wRW7VD82KSR0Ts6viY=; b=FO8a6EWGXzaWgoROld40ZePKhKzvOMsHRriiZ1gMhZLfdYqbpPs3PPf7C9YtBaG3dG weWVL0hkQFSK9fjp2kZNyqBd2auN92drhmopHh6r0LO59k5ykiBEac1qkB46fHVrs+GD PX2WUFB+R9r2TjxJBqrpsArdf7XI2p3tjHtYS3zUfT9K608s7nPrjbFts4pDLV7bR9FH n6xrIjXaifvFUCujBBxVj4RnryC/Ak9nOYHIFoOsU/0rwt2AzLfs3Oab2qCfW83E0/zj tl7OicB3jvuycXToOV0UkO2CZMQ8t1BEUwNE7nCTHAjGbA8CCxDp3dFNR6Qgt0QnQ/WK NWwQ== 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=1BIBOrEM4Q+ZyScf7kriiN6H/wRW7VD82KSR0Ts6viY=; b=LCOalMdfTjZvuL+1t1wcGwq5Fi6I7Hqgo8CKLmPnVpnVnPAexz4iBE0JWvO1tRhKSm fjuI3tKQP0jLF85Dll5jaNSkrObsIwIY8U+qfxIfdaisozh/i4KxvExkuzvrhGu5L7RA BNU+Fstwf5ty78rxFdEb9DmOSfNveVMt2VZ3ADpm0cSWay2wABZRsDhzbT8no9gHw7Fz lnkqssJo+MJ6N2exCQkxIVDAF0VgdtouiKv10feAYofzgN8kIeWDeVKB0OjFvsGJUpVS Pam36YlUBuc8eea8sx9XeddtaZqqThGme0kfeHJB6P3ITIzpDw9yuCbeBLlOy4QFGfDE 55FQ== X-Gm-Message-State: ALyK8tIn3DD9SnkYwnjS/OjIw7eQtvm2s1o1eHi46g0Xchsmlsvzy1Fa8JFL+ApDyM1L4Q== X-Received: by 10.66.248.65 with SMTP id yk1mr4421157pac.56.1467449113890; Sat, 02 Jul 2016 01:45:13 -0700 (PDT) Received: from Karyakshetra ([2401:fa00:c:fd01:410d:2f25:536:9c8f]) by smtp.gmail.com with ESMTPSA id c13sm3247151pfc.40.2016.07.02.01.45.12 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sat, 02 Jul 2016 01:45:13 -0700 (PDT) Date: Sat, 2 Jul 2016 14:15:10 +0530 From: Bhaktipriya Shridhar To: Mark Brown Cc: Tejun Heo , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] spi: spi-sh: Remove deprecated create_singlethread_workqueue Message-ID: <20160702084510.GA27818@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..32ee81c 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);