Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935566Ab2JYLXv (ORCPT ); Thu, 25 Oct 2012 07:23:51 -0400 Received: from mail-vb0-f46.google.com ([209.85.212.46]:63417 "EHLO mail-vb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934799Ab2JYLXt (ORCPT ); Thu, 25 Oct 2012 07:23:49 -0400 MIME-Version: 1.0 In-Reply-To: <1351052091.5263.19.camel@vkoul-udesk3> References: <1349432276-22919-1-git-send-email-inderpal.singh@linaro.org> <1349432276-22919-4-git-send-email-inderpal.singh@linaro.org> <1351052091.5263.19.camel@vkoul-udesk3> Date: Thu, 25 Oct 2012 16:53:49 +0530 Message-ID: Subject: Re: [PATCH v2 3/4] DMA: PL330: Balance module remove function with probe From: Inderpal Singh To: Vinod Koul Cc: vinod.koul@intel.com, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, jassisinghbrar@gmail.com, boojin.kim@samsung.com, patches@linaro.org, kgene.kim@samsung.com Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1934 Lines: 59 Hi Vinod, On 24 October 2012 09:44, Vinod Koul wrote: > On Fri, 2012-10-05 at 15:47 +0530, Inderpal Singh wrote: >> Since peripheral channel resources are not being allocated at probe, >> no need to flush the channels and free the resources in remove function. >> In case, the channel is in use by some client, return EBUSY. >> >> Signed-off-by: Inderpal Singh >> --- >> drivers/dma/pl330.c | 13 ++++++++----- >> 1 file changed, 8 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c >> index bf71ff7..4b7a34d 100644 >> --- a/drivers/dma/pl330.c >> +++ b/drivers/dma/pl330.c >> @@ -3009,18 +3009,21 @@ static int __devexit pl330_remove(struct amba_device *adev) >> if (!pdmac) >> return 0; >> >> + /* check if any client is using any channel */ >> + list_for_each_entry(pch, &pdmac->ddma.channels, >> + chan.device_node) { >> + >> + if (pch->chan.client_count) >> + return -EBUSY; >> + } >> + >> while (!list_empty(&pdmac->desc_pool)) { > > Did you get this code executed? > I think No. > > The dmaengine holds the reference to channels, so if they are in use and > not freed by client your remove wont be called. So this check is > redundant > This code will get executed only in case of force removal of the module which was discussed in the first version of the patch at [1]. Now, if we do not have to think about force removal then this patch will go back to the first version. Let me know your view. [1] https://patchwork.kernel.org/patch/1503171/ Regards, Inder > -- > Vinod Koul > Intel Corp. > -- 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/