From patchwork Thu Aug 26 09:47:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tretter X-Patchwork-Id: 12459367 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F272C432BE for ; Thu, 26 Aug 2021 09:53:07 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0B288610C8 for ; Thu, 26 Aug 2021 09:53:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0B288610C8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=No+RwEylO6bwb50k0D6bTM751G8MTgQDyj7DI96UkTM=; b=Q0aVyt6gYGwRyr h/RR/uHTP/00cOxqoEmmRiR3+SgjwDmPwX3fvbJRIbi/PM+bEQ9b0JfeZlZRMQjVQ1ZwEgJ9pIvwy oorAE8thX07T8FR6V2QDm74xlP5ljpijgfhKC5MY3VT60w0TVggMpNukY8E5Co7zpm3KMMN7SRPT/ Y6IKnt+2rEM+qFQPslMezap82r27ycWziH2ItIrq7u06psdd9DayS12+5MvttFnffenRe7YeTQc01 yn+Fqory59HxMcC04qeoRh1c3a8j56QbyZHYqAzydoC0cWr0dpy+u+5bBd4JCFbvCmkE+ouf1zTxT D0A6LPREb4nYjmTRcg7A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJC1T-009j3S-QJ; Thu, 26 Aug 2021 09:50:12 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mJBzB-009i3G-8D for linux-arm-kernel@lists.infradead.org; Thu, 26 Aug 2021 09:47:53 +0000 Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mJBz8-0003jt-20; Thu, 26 Aug 2021 11:47:46 +0200 Received: from [2a0a:edc0:0:1101:1d::39] (helo=dude03.red.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1mJBz7-0006lp-Bu; Thu, 26 Aug 2021 11:47:45 +0200 Received: from mtr by dude03.red.stw.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1mJBz4-005SjP-9j; Thu, 26 Aug 2021 11:47:42 +0200 From: Michael Tretter To: vkoul@kernel.org, dmaengine@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, appana.durga.rao@xilinx.com, michal.simek@xilinx.com, m.tretter@pengutronix.de, kernel@pengutronix.de Subject: [PATCH 6/7] dmaengine: zynqmp_dma: refine dma descriptor locking Date: Thu, 26 Aug 2021 11:47:41 +0200 Message-Id: <20210826094742.1302009-7-m.tretter@pengutronix.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210826094742.1302009-1-m.tretter@pengutronix.de> References: <20210826094742.1302009-1-m.tretter@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: mtr@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210826_024749_338976_853D1C1B X-CRM114-Status: GOOD ( 12.41 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The descriptor lists are locked for the entire tasklet that completes the descriptors. This is not necessary, because the lock actually only protects the descriptor lists. Make the spin lock more fine-grained and only protect functions that actually operate on the descriptor lists. This decreases the time when the lock is held. Signed-off-by: Michael Tretter --- drivers/dma/xilinx/zynqmp_dma.c | 35 ++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c index f98ef5fe4902..ef32f7519e0a 100644 --- a/drivers/dma/xilinx/zynqmp_dma.c +++ b/drivers/dma/xilinx/zynqmp_dma.c @@ -601,6 +601,9 @@ static void zynqmp_dma_start_transfer(struct zynqmp_dma_chan *chan) static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan) { struct zynqmp_dma_desc_sw *desc, *next; + unsigned long irqflags; + + spin_lock_irqsave(&chan->lock, irqflags); list_for_each_entry_safe(desc, next, &chan->done_list, node) { dma_async_tx_callback callback; @@ -617,6 +620,8 @@ static void zynqmp_dma_chan_desc_cleanup(struct zynqmp_dma_chan *chan) /* Run any dependencies, then free the descriptor */ zynqmp_dma_free_descriptor(chan, desc); } + + spin_unlock_irqrestore(&chan->lock, irqflags); } /** @@ -656,9 +661,13 @@ static void zynqmp_dma_issue_pending(struct dma_chan *dchan) */ static void zynqmp_dma_free_descriptors(struct zynqmp_dma_chan *chan) { + unsigned long irqflags; + + spin_lock_irqsave(&chan->lock, irqflags); zynqmp_dma_free_desc_list(chan, &chan->active_list); zynqmp_dma_free_desc_list(chan, &chan->pending_list); zynqmp_dma_free_desc_list(chan, &chan->done_list); + spin_unlock_irqrestore(&chan->lock, irqflags); } /** @@ -668,11 +677,8 @@ static void zynqmp_dma_free_descriptors(struct zynqmp_dma_chan *chan) static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan) { struct zynqmp_dma_chan *chan = to_chan(dchan); - unsigned long irqflags; - spin_lock_irqsave(&chan->lock, irqflags); zynqmp_dma_free_descriptors(chan); - spin_unlock_irqrestore(&chan->lock, irqflags); dma_free_coherent(chan->dev, (2 * ZYNQMP_DMA_DESC_SIZE(chan) * ZYNQMP_DMA_NUM_DESCS), chan->desc_pool_v, chan->desc_pool_p); @@ -687,11 +693,16 @@ static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan) */ static void zynqmp_dma_reset(struct zynqmp_dma_chan *chan) { + unsigned long irqflags; + writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS); + spin_lock_irqsave(&chan->lock, irqflags); zynqmp_dma_complete_descriptor(chan); + spin_unlock_irqrestore(&chan->lock, irqflags); zynqmp_dma_chan_desc_cleanup(chan); zynqmp_dma_free_descriptors(chan); + zynqmp_dma_init(chan); } @@ -747,28 +758,27 @@ static void zynqmp_dma_do_tasklet(struct tasklet_struct *t) u32 count; unsigned long irqflags; - spin_lock_irqsave(&chan->lock, irqflags); - if (chan->err) { zynqmp_dma_reset(chan); chan->err = false; - goto unlock; + return; } + spin_lock_irqsave(&chan->lock, irqflags); count = readl(chan->regs + ZYNQMP_DMA_IRQ_DST_ACCT); - while (count) { zynqmp_dma_complete_descriptor(chan); count--; } + spin_unlock_irqrestore(&chan->lock, irqflags); zynqmp_dma_chan_desc_cleanup(chan); - if (chan->idle) + if (chan->idle) { + spin_lock_irqsave(&chan->lock, irqflags); zynqmp_dma_start_transfer(chan); - -unlock: - spin_unlock_irqrestore(&chan->lock, irqflags); + spin_unlock_irqrestore(&chan->lock, irqflags); + } } /** @@ -780,12 +790,9 @@ static void zynqmp_dma_do_tasklet(struct tasklet_struct *t) static int zynqmp_dma_device_terminate_all(struct dma_chan *dchan) { struct zynqmp_dma_chan *chan = to_chan(dchan); - unsigned long irqflags; - spin_lock_irqsave(&chan->lock, irqflags); writel(ZYNQMP_DMA_IDS_DEFAULT_MASK, chan->regs + ZYNQMP_DMA_IDS); zynqmp_dma_free_descriptors(chan); - spin_unlock_irqrestore(&chan->lock, irqflags); return 0; }