From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 B64ACECE58E for ; Wed, 9 Oct 2019 10:10:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 997AE206C0 for ; Wed, 9 Oct 2019 10:10:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730419AbfJIKKl (ORCPT ); Wed, 9 Oct 2019 06:10:41 -0400 Received: from foss.arm.com ([217.140.110.172]:58866 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726579AbfJIKKl (ORCPT ); Wed, 9 Oct 2019 06:10:41 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 56F3F28; Wed, 9 Oct 2019 03:10:40 -0700 (PDT) Received: from [192.168.1.124] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EA2923F68E; Wed, 9 Oct 2019 03:10:38 -0700 (PDT) Subject: Re: [PATCH v2] iommu/arm-smmu: fix "hang" when games exit To: Rob Clark , iommu@lists.linux-foundation.org Cc: freedreno@lists.freedesktop.org, Rob Clark , Will Deacon , Joerg Roedel , "moderated list:ARM SMMU DRIVERS" , open list References: <418d8426-f299-1269-2b2e-f86677cf22c2@arm.com> <20191007204906.19571-1-robdclark@gmail.com> From: Robin Murphy Message-ID: Date: Wed, 9 Oct 2019 11:10:33 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:68.0) Gecko/20100101 Thunderbird/68.1.1 MIME-Version: 1.0 In-Reply-To: <20191007204906.19571-1-robdclark@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-10-07 9:49 pm, Rob Clark wrote: > From: Rob Clark > > When games, browser, or anything using a lot of GPU buffers exits, there > can be many hundreds or thousands of buffers to unmap and free. If the > GPU is otherwise suspended, this can cause arm-smmu to resume/suspend > for each buffer, resulting 5-10 seconds worth of reprogramming the > context bank (arm_smmu_write_context_bank()/arm_smmu_write_s2cr()/etc). > To the user it would appear that the system just locked up. > > A simple solution is to use pm_runtime_put_autosuspend() instead, so we > don't immediately suspend the SMMU device. Reviewed-by: Robin Murphy > Signed-off-by: Rob Clark > --- > v1: original > v2: unconditionally use autosuspend, rather than deciding based on what > consumer does > > drivers/iommu/arm-smmu.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 3f1d55fb43c4..b7b41f5001bc 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -289,7 +289,7 @@ static inline int arm_smmu_rpm_get(struct arm_smmu_device *smmu) > static inline void arm_smmu_rpm_put(struct arm_smmu_device *smmu) > { > if (pm_runtime_enabled(smmu->dev)) > - pm_runtime_put(smmu->dev); > + pm_runtime_put_autosuspend(smmu->dev); > } > > static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom) > @@ -1445,6 +1445,9 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) > /* Looks ok, so add the device to the domain */ > ret = arm_smmu_domain_add_master(smmu_domain, fwspec); > > + pm_runtime_set_autosuspend_delay(smmu->dev, 20); > + pm_runtime_use_autosuspend(smmu->dev); > + > rpm_put: > arm_smmu_rpm_put(smmu); > return ret; >