From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sricharan R Subject: Re: [PATCH V4 3/6] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device Date: Thu, 13 Jul 2017 11:05:59 +0530 Message-ID: <4dbc938c-ac88-9bd4-cf00-458008ae24c1@codeaurora.org> References: <1499333825-7658-1-git-send-email-vivek.gautam@codeaurora.org> <1499333825-7658-4-git-send-email-vivek.gautam@codeaurora.org> <20170712225459.GZ22780@codeaurora.org> <5ee0bacd-e557-a6c4-a897-844fb12ea6ae@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5ee0bacd-e557-a6c4-a897-844fb12ea6ae-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Vivek Gautam , Stephen Boyd Cc: mark.rutland-5wv7dgnIgG8@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, stanimir.varbanov-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, linux-clk-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org Hi Vivek, On 7/13/2017 10:43 AM, Vivek Gautam wrote: > Hi Stephen, > > > On 07/13/2017 04:24 AM, Stephen Boyd wrote: >> On 07/06, Vivek Gautam wrote: >>> @@ -1231,12 +1237,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, >>> static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova, >>> size_t size) >>> { >>> - struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; >>> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); >>> + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; >>> + size_t ret; >>> if (!ops) >>> return 0; >>> - return ops->unmap(ops, iova, size); >>> + pm_runtime_get_sync(smmu_domain->smmu->dev); >> Can these map/unmap ops be called from an atomic context? I seem >> to recall that being a problem before. > > That's something which was dropped in the following patch merged in master: > 523d7423e21b iommu/arm-smmu: Remove io-pgtable spinlock > > Looks like we don't need locks here anymore? Apart from the locking, wonder why a explicit pm_runtime is needed from unmap. Somehow looks like some path in the master using that should have enabled the pm ? Regards, Sricharan -- "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751004AbdGMFgL (ORCPT ); Thu, 13 Jul 2017 01:36:11 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:47206 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750748AbdGMFgJ (ORCPT ); Thu, 13 Jul 2017 01:36:09 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 3299E61289 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=sricharan@codeaurora.org Subject: Re: [PATCH V4 3/6] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device To: Vivek Gautam , Stephen Boyd Cc: joro@8bytes.org, robin.murphy@arm.com, robh+dt@kernel.org, mark.rutland@arm.com, will.deacon@arm.com, m.szyprowski@samsung.com, robdclark@gmail.com, iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-msm@vger.kernel.org, stanimir.varbanov@linaro.org, architt@codeaurora.org, linux-arm-kernel@lists.infradead.org References: <1499333825-7658-1-git-send-email-vivek.gautam@codeaurora.org> <1499333825-7658-4-git-send-email-vivek.gautam@codeaurora.org> <20170712225459.GZ22780@codeaurora.org> <5ee0bacd-e557-a6c4-a897-844fb12ea6ae@codeaurora.org> From: Sricharan R Message-ID: <4dbc938c-ac88-9bd4-cf00-458008ae24c1@codeaurora.org> Date: Thu, 13 Jul 2017 11:05:59 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <5ee0bacd-e557-a6c4-a897-844fb12ea6ae@codeaurora.org> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Antivirus: Avast (VPS 170712-10, 07/12/2017), Outbound message X-Antivirus-Status: Clean Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Vivek, On 7/13/2017 10:43 AM, Vivek Gautam wrote: > Hi Stephen, > > > On 07/13/2017 04:24 AM, Stephen Boyd wrote: >> On 07/06, Vivek Gautam wrote: >>> @@ -1231,12 +1237,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, >>> static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova, >>> size_t size) >>> { >>> - struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; >>> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); >>> + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; >>> + size_t ret; >>> if (!ops) >>> return 0; >>> - return ops->unmap(ops, iova, size); >>> + pm_runtime_get_sync(smmu_domain->smmu->dev); >> Can these map/unmap ops be called from an atomic context? I seem >> to recall that being a problem before. > > That's something which was dropped in the following patch merged in master: > 523d7423e21b iommu/arm-smmu: Remove io-pgtable spinlock > > Looks like we don't need locks here anymore? Apart from the locking, wonder why a explicit pm_runtime is needed from unmap. Somehow looks like some path in the master using that should have enabled the pm ? Regards, Sricharan -- "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus From mboxrd@z Thu Jan 1 00:00:00 1970 From: sricharan@codeaurora.org (Sricharan R) Date: Thu, 13 Jul 2017 11:05:59 +0530 Subject: [PATCH V4 3/6] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device In-Reply-To: <5ee0bacd-e557-a6c4-a897-844fb12ea6ae@codeaurora.org> References: <1499333825-7658-1-git-send-email-vivek.gautam@codeaurora.org> <1499333825-7658-4-git-send-email-vivek.gautam@codeaurora.org> <20170712225459.GZ22780@codeaurora.org> <5ee0bacd-e557-a6c4-a897-844fb12ea6ae@codeaurora.org> Message-ID: <4dbc938c-ac88-9bd4-cf00-458008ae24c1@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Vivek, On 7/13/2017 10:43 AM, Vivek Gautam wrote: > Hi Stephen, > > > On 07/13/2017 04:24 AM, Stephen Boyd wrote: >> On 07/06, Vivek Gautam wrote: >>> @@ -1231,12 +1237,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, >>> static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova, >>> size_t size) >>> { >>> - struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; >>> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); >>> + struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops; >>> + size_t ret; >>> if (!ops) >>> return 0; >>> - return ops->unmap(ops, iova, size); >>> + pm_runtime_get_sync(smmu_domain->smmu->dev); >> Can these map/unmap ops be called from an atomic context? I seem >> to recall that being a problem before. > > That's something which was dropped in the following patch merged in master: > 523d7423e21b iommu/arm-smmu: Remove io-pgtable spinlock > > Looks like we don't need locks here anymore? Apart from the locking, wonder why a explicit pm_runtime is needed from unmap. Somehow looks like some path in the master using that should have enabled the pm ? Regards, Sricharan -- "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus