From patchwork Mon Apr 23 13:51:43 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 154454 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id D0EC2B6EEB for ; Mon, 23 Apr 2012 23:58:13 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755501Ab2DWN4T (ORCPT ); Mon, 23 Apr 2012 09:56:19 -0400 Received: from mail-pz0-f51.google.com ([209.85.210.51]:45199 "EHLO mail-pz0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752454Ab2DWN4S (ORCPT ); Mon, 23 Apr 2012 09:56:18 -0400 Received: by mail-pz0-f51.google.com with SMTP id z8so15592682dad.10 for ; Mon, 23 Apr 2012 06:56:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=s0cZvZc2qInwUOeI0teekjpkV4clb86KVcOBRPSKQCg=; b=Kn/fISErx3TFm645iEcNQbBwQJDR2xnrQlkncKk/W0oukxVo/4HrPDQrNVxf8mAfpy J3M4RhKuavabTMwMtPeI7+ymjqOBsz/ssUSH9UFyCHTtxFWIZCO76bYPwI2Kp3pjRjiZ SH332wLJqAZLGIJ6B9wBC3/tSjf2alsdbwG9v6dAr9jaB/ZUcyGmkGuprqO+welE6/VO zVAymMV6BLQhl7IdfO8j9wkXC7nxLw9rQp2ml/zLThnbWFVHALD9kq6nVBeGYR2SezY+ 9nSfg4Dc3LZ6zcAtNXakwV4pPbC11RhHEdCYbpFrDZYXpfbl0GdBvRSRaE5jqjiGgueJ F6hA== Received: by 10.68.217.201 with SMTP id pa9mr762022pbc.73.1335189377832; Mon, 23 Apr 2012 06:56:17 -0700 (PDT) Received: from localhost.localdomain ([221.221.17.121]) by mx.google.com with ESMTPS id q1sm14443839pbp.62.2012.04.23.06.56.10 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 23 Apr 2012 06:56:16 -0700 (PDT) From: Jiang Liu To: Vinod Koul , Dan Williams Cc: Jiang Liu , Keping Chen , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Jiang Liu Subject: [PATCH v1 2/8] dmaengine: rebalance DMA channels when CPU hotplug happens Date: Mon, 23 Apr 2012 21:51:43 +0800 Message-Id: <1335189109-4871-3-git-send-email-jiang.liu@huawei.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1335189109-4871-1-git-send-email-jiang.liu@huawei.com> References: <1335189109-4871-1-git-send-email-jiang.liu@huawei.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Rebalance DMA channels when CPU hotplug happens to correctly update DMA channel reference count. Signed-off-by: Jiang Liu --- drivers/dma/dmaengine.c | 22 ++++++++++++++++++++++ 1 files changed, 22 insertions(+), 0 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 5b6ad58..198d891 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -49,6 +49,7 @@ #include #include #include +#include #include #include #include @@ -1008,8 +1009,29 @@ void dma_run_dependencies(struct dma_async_tx_descriptor *tx) } EXPORT_SYMBOL_GPL(dma_run_dependencies); +static int __cpuinit +hotcpu_rebalance(struct notifier_block *nfb, unsigned long action, void *hcpu) +{ + switch (action) { + case CPU_ONLINE: + case CPU_POST_DEAD: + mutex_lock(&dma_list_mutex); + dma_channel_rebalance(); + mutex_unlock(&dma_list_mutex); + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block __refdata dma_cpu_notifier = { + .notifier_call = hotcpu_rebalance, +}; + + static int __init dma_bus_init(void) { + register_hotcpu_notifier(&dma_cpu_notifier); return class_register(&dma_devclass); } arch_initcall(dma_bus_init);