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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 BF9DDC43381 for ; Sat, 30 Mar 2019 10:43:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E97D218A6 for ; Sat, 30 Mar 2019 10:43:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730674AbfC3Kn3 (ORCPT ); Sat, 30 Mar 2019 06:43:29 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:5766 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730372AbfC3Kn2 (ORCPT ); Sat, 30 Mar 2019 06:43:28 -0400 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 0776732697C53D56B0E6; Sat, 30 Mar 2019 18:43:24 +0800 (CST) Received: from [127.0.0.1] (10.177.23.164) by DGGEMS409-HUB.china.huawei.com (10.3.19.209) with Microsoft SMTP Server id 14.3.408.0; Sat, 30 Mar 2019 18:43:16 +0800 Subject: Re: [PATCH v3 1/1] iommu: Add config option to set lazy mode as default To: Jean-Philippe Brucker , John Garry , Robin Murphy , Will Deacon , Joerg Roedel , iommu , linux-kernel References: <20190329025423.15484-1-thunder.leizhen@huawei.com> CC: S390 , Hanjun Guo From: "Leizhen (ThunderTown)" Message-ID: <5C9F4843.9010307@huawei.com> Date: Sat, 30 Mar 2019 18:43:15 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20190329025423.15484-1-thunder.leizhen@huawei.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.177.23.164] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/3/29 10:54, Zhen Lei wrote: > This allows the default behaviour to be controlled by a kernel config > option instead of changing the command line for the kernel to include > "iommu.strict=0" on ARM64 where this is desired. > > This is similar to CONFIG_IOMMU_DEFAULT_PASSTHROUGH. > > Signed-off-by: Zhen Lei > --- > arch/s390/pci/pci_dma.c | 4 ++++ > drivers/iommu/Kconfig | 15 +++++++++++++++ > drivers/iommu/amd_iommu_init.c | 6 +++++- > drivers/iommu/intel-iommu.c | 4 ++++ > drivers/iommu/iommu.c | 5 +++++ > 5 files changed, 33 insertions(+), 1 deletion(-) > > diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c > index 9e52d1527f71495..d05e8c3820793c5 100644 > --- a/arch/s390/pci/pci_dma.c > +++ b/arch/s390/pci/pci_dma.c > @@ -17,7 +17,11 @@ > > static struct kmem_cache *dma_region_table_cache; > static struct kmem_cache *dma_page_table_cache; > +#ifdef CONFIG_IOMMU_DMA_DEFAULT_LAZY_MODE > static int s390_iommu_strict; > +#else > +static int s390_iommu_strict = 1; > +#endif > > static int zpci_refresh_global(struct zpci_dev *zdev) > { > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index 6f07f3b21816c64..ed5206a2d316599 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -85,6 +85,21 @@ config IOMMU_DEFAULT_PASSTHROUGH > > If unsure, say N here. > > +config IOMMU_DMA_DEFAULT_LAZY_MODE > + bool "IOMMU DMA use lazy mode to flush IOTLB and free IOVA" > + depends on IOMMU_API > + default y Hi Robin： Should I change to: + default y if !(ARM_SMMU || ARM_SMMU_V3) > + help > + Support lazy mode, where for every IOMMU DMA unmap operation, the > + flush operation of IOTLB and the free operation of IOVA are deferred. > + They are only guaranteed to be done before the related IOVA will be > + reused. Removing the need to pass in kernel parameters through > + command line. For example, iommu.strict=0 on ARM64. If this is > + enabled, you can still disable with kernel parameters, such as > + iommu.strict=1 depending on the architecture. > + > + If unsure, say N here. > + > config OF_IOMMU > def_bool y > depends on OF && IOMMU_API > diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c > index f773792d77fd533..a30805c2f77199c 100644 > --- a/drivers/iommu/amd_iommu_init.c > +++ b/drivers/iommu/amd_iommu_init.c > @@ -166,7 +166,11 @@ struct ivmd_header { > to handle */ > LIST_HEAD(amd_iommu_unity_map); /* a list of required unity mappings > we find in ACPI */ > -bool amd_iommu_unmap_flush; /* if true, flush on every unmap */ > +#ifdef CONFIG_IOMMU_DMA_DEFAULT_LAZY_MODE > +bool amd_iommu_unmap_flush; > +#else > +bool amd_iommu_unmap_flush = true; /* flush on every unmap */ > +#endif > > LIST_HEAD(amd_iommu_list); /* list of all AMD IOMMUs in the > system */ > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index 28cb713d728ceef..560191a9342b2b8 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -362,7 +362,11 @@ static int domain_detach_iommu(struct dmar_domain *domain, > > static int dmar_map_gfx = 1; > static int dmar_forcedac; > +#ifdef CONFIG_IOMMU_DMA_DEFAULT_LAZY_MODE > static int intel_iommu_strict; > +#else > +static int intel_iommu_strict = 1; > +#endif > static int intel_iommu_superpage = 1; > static int intel_iommu_sm; > static int iommu_identity_mapping; > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 33a982e33716369..5acb98e79b5b32d 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -43,7 +43,12 @@ > #else > static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; > #endif > + > +#ifdef CONFIG_IOMMU_DMA_DEFAULT_LAZY_MODE > +static bool iommu_dma_strict __read_mostly; > +#else > static bool iommu_dma_strict __read_mostly = true; > +#endif > > struct iommu_callback_data { > const struct iommu_ops *ops; > -- Thanks! BestRegards