Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756774Ab2ENNuE (ORCPT ); Mon, 14 May 2012 09:50:04 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:49717 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755030Ab2ENNuC (ORCPT ); Mon, 14 May 2012 09:50:02 -0400 From: Jiang Liu To: Dan Williams , Maciej Sosnowski , Vinod Koul Cc: Jiang Liu , Keping Chen , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Jiang Liu Subject: [RFC PATCH v2 2/7] dmaengine: rebalance DMA channels when CPU hotplug happens Date: Mon, 14 May 2012 21:47:04 +0800 Message-Id: <1337003229-9158-3-git-send-email-jiang.liu@huawei.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1337003229-9158-1-git-send-email-jiang.liu@huawei.com> References: <1337003229-9158-1-git-send-email-jiang.liu@huawei.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1589 Lines: 60 From: Jiang Liu 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 file changed, 22 insertions(+) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index 58bc45c..d3b1c48 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -49,6 +49,7 @@ #include #include #include +#include #include #include #include @@ -1003,8 +1004,29 @@ 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); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/