From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="MhEH56cU" Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D1681FDF for ; Tue, 28 Nov 2023 13:34:36 -0800 (PST) Received: by mail-ej1-x629.google.com with SMTP id a640c23a62f3a-a0b7f793b8aso488841466b.2 for ; Tue, 28 Nov 2023 13:34:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1701207275; x=1701812075; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=8NXFzGfhAzOfJO06Gf5RsXFoYKrXmtsSvTLzk7MbcCk=; b=MhEH56cUgeYVrXUDfslmi4RJuwodrwS8+9YvwSqfWrEThOZvoUtvlDSVQpBSgwjQOW KQXPypmhj/Tsc4s2STMcNHypwkApqjhiC4loLMebrlT1wZD6GSwYks2cgficn/lxJ1/u aHggR40HTITk1MS1FeVRp4CVHHTgdQkTwwfT06aP3UXwypQ6Wd0+qeEKvITwX61G/SSs RlDDIyMGwItn+9Nc3JYZZNmvoTdneH1EzrQT2ziIdTv7wfGxBNv3w0uVwzAQZj5tNI8x dGXG3O6iIAgTPA2ROHC+6nYYzb0VRZ7BOqZL0dQ0utSrDvXyMi75nwcMx0u1/SDtl1cq TPkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701207275; x=1701812075; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8NXFzGfhAzOfJO06Gf5RsXFoYKrXmtsSvTLzk7MbcCk=; b=VV1jvhZQJbuSMIQbKLE2Eut9wSiKHcgxJcQKZcH6efw6c/jY7OAQ9Axt7bKmfRD0LE 9/HQb7tsoCMaoAJxK5zap6WUfUQ4X7bUxuYczmPKzlfyH701bClW2kwnUsu5GK4dGv2j xerGy8sH8CQv6XoJKEt1AipffXnD1xJtU06TG+UoTe0IlcbhrUHSruLGbB2hXoIj7nJS devQgKpHXHdxSA/h7TsxtcErKkhC/9foyg8IXIiO6uyoMOzrdTKKm9Cx2VLx1H13wpIO RO4lxESTqmeuElIYjhqKoI7IJT+gZ67isIENsiSKkbGcga4+VkfC2AjT35920BSQJXHI D7Cw== X-Gm-Message-State: AOJu0Yx4JER7xNIkghGJ9qItMSSZlzJ0gtDWaSakkeL4Lf9IRXZglw+S hFPA9Ck3zs1v2Ay36f8icAmv6ZTdDjoI8W9ddEfOCA== X-Google-Smtp-Source: AGHT+IFrrdaJl+8CDzGqIseL+lJ7M7KDt9GszVwJUOFBD/DHsSLfgFwP8+NKKfkfsTtyJyGUtnD8OJJylXlFpNkSb5g= X-Received: by 2002:a17:906:b248:b0:a04:cc0e:ff3b with SMTP id ce8-20020a170906b24800b00a04cc0eff3bmr12465188ejb.27.1701207274446; Tue, 28 Nov 2023 13:34:34 -0800 (PST) Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20231128204938.1453583-1-pasha.tatashin@soleen.com> In-Reply-To: <20231128204938.1453583-1-pasha.tatashin@soleen.com> From: Yosry Ahmed Date: Tue, 28 Nov 2023 13:33:55 -0800 Message-ID: Subject: Re: [PATCH 00/16] IOMMU memory observability To: Pasha Tatashin Cc: akpm@linux-foundation.org, alex.williamson@redhat.com, alim.akhtar@samsung.com, alyssa@rosenzweig.io, asahi@lists.linux.dev, baolu.lu@linux.intel.com, bhelgaas@google.com, cgroups@vger.kernel.org, corbet@lwn.net, david@redhat.com, dwmw2@infradead.org, hannes@cmpxchg.org, heiko@sntech.de, iommu@lists.linux.dev, jasowang@redhat.com, jernej.skrabec@gmail.com, jgg@ziepe.ca, jonathanh@nvidia.com, joro@8bytes.org, kevin.tian@intel.com, krzysztof.kozlowski@linaro.org, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-rockchip@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-sunxi@lists.linux.dev, linux-tegra@vger.kernel.org, lizefan.x@bytedance.com, marcan@marcan.st, mhiramat@kernel.org, mst@redhat.com, m.szyprowski@samsung.com, netdev@vger.kernel.org, paulmck@kernel.org, rdunlap@infradead.org, robin.murphy@arm.com, samuel@sholland.org, suravee.suthikulpanit@amd.com, sven@svenpeter.dev, thierry.reding@gmail.com, tj@kernel.org, tomas.mudrunka@gmail.com, vdumpa@nvidia.com, virtualization@lists.linux.dev, wens@csie.org, will@kernel.org, yu-cheng.yu@intel.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, Nov 28, 2023 at 12:49=E2=80=AFPM Pasha Tatashin wrote: > > From: Pasha Tatashin > > IOMMU subsystem may contain state that is in gigabytes. Majority of that > state is iommu page tables. Yet, there is currently, no way to observe > how much memory is actually used by the iommu subsystem. > > This patch series solves this problem by adding both observability to > all pages that are allocated by IOMMU, and also accountability, so > admins can limit the amount if via cgroups. > > The system-wide observability is using /proc/meminfo: > SecPageTables: 438176 kB > > Contains IOMMU and KVM memory. > > Per-node observability: > /sys/devices/system/node/nodeN/meminfo > Node N SecPageTables: 422204 kB > > Contains IOMMU and KVM memory memory in the given NUMA node. > > Per-node IOMMU only observability: > /sys/devices/system/node/nodeN/vmstat > nr_iommu_pages 105555 > > Contains number of pages IOMMU allocated in the given node. Does it make sense to have a KVM-only entry there as well? In that case, if SecPageTables in /proc/meminfo is found to be suspiciously high, it should be easy to tell which component is contributing most usage through vmstat. I understand that users can do the subtraction, but we wouldn't want userspace depending on that, in case a third class of "secondary" page tables emerges that we want to add to SecPageTables. The in-kernel implementation can do the subtraction for now if it makes sense though. > > Accountability: using sec_pagetables cgroup-v2 memory.stat entry. > > With the change, iova_stress[1] stops as limit is reached: > > # ./iova_stress > iova space: 0T free memory: 497G > iova space: 1T free memory: 495G > iova space: 2T free memory: 493G > iova space: 3T free memory: 491G > > stops as limit is reached. > > This series encorporates suggestions that came from the discussion > at LPC [2]. > > [1] https://github.com/soleen/iova_stress > [2] https://lpc.events/event/17/contributions/1466 > > Pasha Tatashin (16): > iommu/vt-d: add wrapper functions for page allocations > iommu/amd: use page allocation function provided by iommu-pages.h > iommu/io-pgtable-arm: use page allocation function provided by > iommu-pages.h > iommu/io-pgtable-dart: use page allocation function provided by > iommu-pages.h > iommu/io-pgtable-arm-v7s: use page allocation function provided by > iommu-pages.h > iommu/dma: use page allocation function provided by iommu-pages.h > iommu/exynos: use page allocation function provided by iommu-pages.h > iommu/fsl: use page allocation function provided by iommu-pages.h > iommu/iommufd: use page allocation function provided by iommu-pages.h > iommu/rockchip: use page allocation function provided by iommu-pages.h > iommu/sun50i: use page allocation function provided by iommu-pages.h > iommu/tegra-smmu: use page allocation function provided by > iommu-pages.h > iommu: observability of the IOMMU allocations > iommu: account IOMMU allocated memory > vhost-vdpa: account iommu allocations > vfio: account iommu allocations > > Documentation/admin-guide/cgroup-v2.rst | 2 +- > Documentation/filesystems/proc.rst | 4 +- > drivers/iommu/amd/amd_iommu.h | 8 - > drivers/iommu/amd/init.c | 91 +++++----- > drivers/iommu/amd/io_pgtable.c | 13 +- > drivers/iommu/amd/io_pgtable_v2.c | 20 +- > drivers/iommu/amd/iommu.c | 13 +- > drivers/iommu/dma-iommu.c | 8 +- > drivers/iommu/exynos-iommu.c | 14 +- > drivers/iommu/fsl_pamu.c | 5 +- > drivers/iommu/intel/dmar.c | 10 +- > drivers/iommu/intel/iommu.c | 47 ++--- > drivers/iommu/intel/iommu.h | 2 - > drivers/iommu/intel/irq_remapping.c | 10 +- > drivers/iommu/intel/pasid.c | 12 +- > drivers/iommu/intel/svm.c | 7 +- > drivers/iommu/io-pgtable-arm-v7s.c | 9 +- > drivers/iommu/io-pgtable-arm.c | 7 +- > drivers/iommu/io-pgtable-dart.c | 37 ++-- > drivers/iommu/iommu-pages.h | 231 ++++++++++++++++++++++++ > drivers/iommu/iommufd/iova_bitmap.c | 6 +- > drivers/iommu/rockchip-iommu.c | 14 +- > drivers/iommu/sun50i-iommu.c | 7 +- > drivers/iommu/tegra-smmu.c | 18 +- > drivers/vfio/vfio_iommu_type1.c | 8 +- > drivers/vhost/vdpa.c | 3 +- > include/linux/mmzone.h | 5 +- > mm/vmstat.c | 3 + > 28 files changed, 415 insertions(+), 199 deletions(-) > create mode 100644 drivers/iommu/iommu-pages.h > > -- > 2.43.0.rc2.451.g8631bc7472-goog > >