From patchwork Fri Feb 11 16:18:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "T.J. Mercier" X-Patchwork-Id: 541961 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77F3AC433EF for ; Fri, 11 Feb 2022 16:18:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351251AbiBKQSv (ORCPT ); Fri, 11 Feb 2022 11:18:51 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:46640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233594AbiBKQSu (ORCPT ); Fri, 11 Feb 2022 11:18:50 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E7902E5 for ; Fri, 11 Feb 2022 08:18:48 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id b187-20020a251bc4000000b0061e15c5024fso19551991ybb.4 for ; Fri, 11 Feb 2022 08:18:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc:content-transfer-encoding; bh=kKcjEXjOeEH0mGAkUcoWrOf4L77tAlhRMN7oO+B50iM=; b=T9LUWLemzPZzWYno8+slJF7qkK9H6xZtLOTMdahBN5x+c0VFhJMUx8wFWEMkCbnPAF c49tzOGzV24vKh6ZcteeJfm3K/h9dxxJPqP4MdiFOtfB6ha8vES8N3btoQrzDj99NC6N NThuVzfB1W1O0Kh++ZNdvtrId5jUcr1F28amVcqkRC74pjDyEHpBeQS8e/cQfBjFt7hj X67UvBvdRjeJR8maJKVWPqHkmcP8r4DnFCaYNX+KPCQut2f8zjoSvF0Y11POa8xywdg4 pNi7vTlLa3ElD0YVicbwppcwiTNNz6d3MAEHWfh4tsR1cEwGnXSja5hctDRznDh1fBfM Jfvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc:content-transfer-encoding; bh=kKcjEXjOeEH0mGAkUcoWrOf4L77tAlhRMN7oO+B50iM=; b=1f6KE3f90fKFTu8UWOuaOOP/L7TMmV99EjSbHUTg5ONJr757TOh2SnOIVIhZYaqsLK gaWZGAOXdTOEhN6bms3gwxL9GblJOu7CKfsqxwSm+6YiKLHrmv0pmm24aR/nVi5SLyk8 A6kqZFB6/Pi8QnOWUX180p6ZORZcpicFUK7IyiKQSR4aNDoGjjZTuGrPLIElmjqdSZj2 2Ri63UqdX9Quv+zDUl6ywEmac+K4Prkqt8QNLFn/0RIQmkSrSR8xaFu+0bxEqoBB6LRm If+kAPvxRjaUhb0fvqXVFPBP2GN6W9ZCMIN5ubwl9DY7jFUy1L8DigowrWHm4WgWfxbj RPPA== X-Gm-Message-State: AOAM531H05lnEOXztg2IcvkSY/4ZpUHvdRAaDDVs8yYjbBzdHiZ9fSib cHJmlr7gpRcFmR/nDseL/u3rAxORob/kkpg= X-Google-Smtp-Source: ABdhPJycT0YOG160oFos0c32qQdd1BG3KkZireh624cMDeZCi951f8jFV6xjhpQwy90JhdPUdi2Jed9M+wpOVmI= X-Received: from tj2.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:187]) (user=tjmercier job=sendgmr) by 2002:a25:8a8a:: with SMTP id h10mr1988762ybl.49.1644596327676; Fri, 11 Feb 2022 08:18:47 -0800 (PST) Date: Fri, 11 Feb 2022 16:18:24 +0000 In-Reply-To: <20220211161831.3493782-1-tjmercier@google.com> Message-Id: <20220211161831.3493782-2-tjmercier@google.com> Mime-Version: 1.0 References: <20220211161831.3493782-1-tjmercier@google.com> X-Mailer: git-send-email 2.35.1.265.g69c8d7142f-goog Subject: [RFC v2 1/6] gpu: rfc: Proposal for a GPU cgroup controller From: "T.J. Mercier" To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Jonathan Corbet , Greg Kroah-Hartman , " =?utf-8?q?Arve_Hj=C3=B8n?= =?utf-8?q?nev=C3=A5g?= " , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Hridya Valsaraju , Suren Baghdasaryan , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Benjamin Gaignard , Liam Mark , Laura Abbott , Brian Starkey , John Stultz , Tejun Heo , Zefan Li , Johannes Weiner Cc: kaleshsingh@google.com, Kenny.Ho@amd.com, "T.J. Mercier" , dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, cgroups@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org This patch adds a proposal for a new GPU cgroup controller for accounting/limiting GPU and GPU-related memory allocations. The proposed controller is based on the DRM cgroup controller[1] and follows the design of the RDMA cgroup controller. The new cgroup controller would: * Allow setting per-cgroup limits on the total size of buffers charged to it. * Allow setting per-device limits on the total size of buffers allocated by device within a cgroup. * Expose a per-device/allocator breakdown of the buffers charged to a cgroup. The prototype in the following patches is only for memory accounting using the GPU cgroup controller and does not implement limit setting. [1]: https://lore.kernel.org/amd-gfx/20210126214626.16260-1-brian.welty@intel.com/ From: Hridya Valsaraju Signed-off-by: Hridya Valsaraju Co-developed-by: T.J. Mercier Signed-off-by: T.J. Mercier --- Documentation/gpu/rfc/gpu-cgroup.rst | 195 +++++++++++++++++++++++++++ Documentation/gpu/rfc/index.rst | 4 + 2 files changed, 199 insertions(+) create mode 100644 Documentation/gpu/rfc/gpu-cgroup.rst diff --git a/Documentation/gpu/rfc/gpu-cgroup.rst b/Documentation/gpu/rfc/gpu-cgroup.rst new file mode 100644 index 000000000000..0bb761223b97 --- /dev/null +++ b/Documentation/gpu/rfc/gpu-cgroup.rst @@ -0,0 +1,195 @@ +=================================== +GPU cgroup controller +=================================== + +Goals +===== +This document intends to outline a plan to create a cgroup v2 controller subsystem +for the per-cgroup accounting of device and system memory allocated by the GPU +and related subsystems. + +The new cgroup controller would: + +* Allow setting per-cgroup limits on the total size of buffers charged to it. + +* Allow setting per-device limits on the total size of buffers allocated by a + device/allocator within a cgroup. + +* Expose a per-device/allocator breakdown of the buffers charged to a cgroup. + +Alternatives Considered +======================= + +The following alternatives were considered: + +The memory cgroup controller +____________________________ + +1. As was noted in [1], memory accounting provided by the GPU cgroup +controller is not a good fit for integration into memcg due to the +differences in how accounting is performed. It implements a mechanism +for the allocator attribution of GPU and GPU-related memory by +charging each buffer to the cgroup of the process on behalf of which +the memory was allocated. The buffer stays charged to the cgroup until +it is freed regardless of whether the process retains any references +to it. On the other hand, the memory cgroup controller offers a more +fine-grained charging and uncharging behavior depending on the kind of +page being accounted. + +2. Memcg performs accounting in units of pages. In the DMA-BUF buffer sharing model, +a process takes a reference to the entire buffer(hence keeping it alive) even if +it is only accessing parts of it. Therefore, per-page memory tracking for DMA-BUF +memory accounting would only introduce additional overhead without any benefits. + +[1]: https://patchwork.kernel.org/project/dri-devel/cover/20190501140438.9506-1-brian.welty@intel.com/#22624705 + +Userspace service to keep track of buffer allocations and releases +__________________________________________________________________ + +1. There is no way for a userspace service to intercept all allocations and releases. +2. In case the process gets killed or restarted, we lose all accounting so far. + +UAPI +==== +When enabled, the new cgroup controller would create the following files in every cgroup. + +:: + + gpu.memory.current (R) + gpu.memory.max (R/W) + +gpu.memory.current is a read-only file and would contain per-device memory allocations +in a key-value format where key is a string representing the device name +and the value is the size of memory charged to the device in the cgroup in bytes. + +For example: + +:: + + cat /sys/kernel/fs/cgroup1/gpu.memory.current + dev1 4194304 + dev2 4194304 + +The string key for each device is set by the device driver when the device registers +with the GPU cgroup controller to participate in resource accounting(see section +'Design and Implementation' for more details). + +gpu.memory.max is a read/write file. It would show the current total +size limits on memory usage for the cgroup and the limits on total memory usage +for each allocator/device. + +Setting a total limit for a cgroup can be done as follows: + +:: + + echo “total 41943040” > /sys/kernel/fs/cgroup1/gpu.memory.max + +Setting a total limit for a particular device/allocator can be done as follows: + +:: + + echo “dev1 4194304” > /sys/kernel/fs/cgroup1/gpu.memory.max + +In this example, 'dev1' is the string key set by the device driver during +registration. + +Design and Implementation +========================= + +The cgroup controller would closely follow the design of the RDMA cgroup controller +subsystem where each cgroup maintains a list of resource pools. +Each resource pool contains a struct device and the counter to track current total, +and the maximum limit set for the device. + +The below code block is a preliminary estimation on how the core kernel data structures +and APIs would look like. + +.. code-block:: c + + /** + * The GPU cgroup controller data structure. + */ + struct gpucg { + struct cgroup_subsys_state css; + + /* list of all resource pools that belong to this cgroup */ + struct list_head rpools; + }; + + struct gpucg_device { + /* + * list of various resource pools in various cgroups that the device is + * part of. + */ + struct list_head rpools; + + /* list of all devices registered for GPU cgroup accounting */ + struct list_head dev_node; + + /* name to be used as identifier for accounting and limit setting */ + const char *name; + }; + + struct gpucg_resource_pool { + /* The device whose resource usage is tracked by this resource pool */ + struct gpucg_device *device; + + /* list of all resource pools for the cgroup */ + struct list_head cg_node; + + /* + * list maintained by the gpucg_device to keep track of its + * resource pools + */ + struct list_head dev_node; + + /* tracks memory usage of the resource pool */ + struct page_counter total; + }; + + /** + * gpucg_register_device - Registers a device for memory accounting using the + * GPU cgroup controller. + * + * @device: The device to register for memory accounting. Must remain valid + * after registration. + * @name: Pointer to a string literal to denote the name of the device. + */ + void gpucg_register_device(struct gpucg_device *gpucg_dev, const char *name); + + /** + * gpucg_try_charge - charge memory to the specified gpucg and gpucg_device. + * + * @gpucg: The gpu cgroup to charge the memory to. + * @device: The device to charge the memory to. + * @usage: size of memory to charge in bytes. + * + * Return: returns 0 if the charging is successful and otherwise returns an + * error code. + */ + int gpucg_try_charge(struct gpucg *gpucg, struct gpucg_device *device, u64 usage); + + /** + * gpucg_uncharge - uncharge memory from the specified gpucg and gpucg_device. + * + * @gpucg: The gpu cgroup to uncharge the memory from. + * @device: The device to charge the memory from. + * @usage: size of memory to uncharge in bytes. + */ + void gpucg_uncharge(struct gpucg *gpucg, struct gpucg_device *device, u64 usage); + +Future Work +=========== +Additional GPU resources can be supported by adding new controller files. + +Upstreaming Plan +================ +* Decide on a UAPI that accommodates all use-cases for the upstream GPU ecosystem + as well as for Android. + +* Prototype the GPU cgroup controller and integrate its usage into the DMA-BUF + system heap. + +* Demonstrate its usage from userspace in the Android Open Space Project. + +* Send out RFCs to LKML for the GPU cgroup controller and iterate. diff --git a/Documentation/gpu/rfc/index.rst b/Documentation/gpu/rfc/index.rst index 91e93a705230..0a9bcd94e95d 100644 --- a/Documentation/gpu/rfc/index.rst +++ b/Documentation/gpu/rfc/index.rst @@ -23,3 +23,7 @@ host such documentation: .. toctree:: i915_scheduler.rst + +.. toctree:: + + gpu-cgroup.rst From patchwork Fri Feb 11 16:18:26 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "T.J. Mercier" X-Patchwork-Id: 541960 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF312C433EF for ; Fri, 11 Feb 2022 16:19:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351377AbiBKQTF (ORCPT ); Fri, 11 Feb 2022 11:19:05 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:46992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351409AbiBKQTD (ORCPT ); Fri, 11 Feb 2022 11:19:03 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E5B52EB for ; Fri, 11 Feb 2022 08:18:59 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id 3-20020a250103000000b0061d99b7d0b8so19763585ybb.13 for ; Fri, 11 Feb 2022 08:18:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc:content-transfer-encoding; bh=sjycs3J1raw78h/CcVrcAvxXNJMm38YGwWJkg+hcSJk=; b=HCicQU9wOvrep9Zko1Sp6f1kcNJH7vA3zXU3TjVhgtj7ecoJwQbiD5zNwlfXKnd3Uk fKTPKQahF2g4Y6Yl7OC7kdWe7Xj8Eip01fQ6bgZwKtUVfM3OdrQeD+P6IfjP4J6lHMxA 3Wd8KCv9vSHVzLrGft5zgckgtzVcnmXlHGqDJHcNNED707tgW9lJ0MnWqLKY0kp2dvQ/ UUurtSGmuV/6T387NDPTkYw+EQTiIjeuuZAohK9DBXj7o64/5JeY3gPt76JuMQ8y3+Fu NHs0H9pPGSnyHfRViau6furuWINKT4TIcOBlhZR4UuboJcrJaNNaihVZN+Vu6nhzK9qs mgTg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc:content-transfer-encoding; bh=sjycs3J1raw78h/CcVrcAvxXNJMm38YGwWJkg+hcSJk=; b=hEfFjnyoL2dGc3m7sbKa1Kxo0O14lBuMw7gqss+koSOwiPxtpVwoSC/+fWuGxAKflD h47nBsieCjghswf6rcHnLUL50HvIkvEoq8h5Fz4OjJksi3YIObit4YM9bG/dYdF46urp nZDet6HlTzjIq91khvnt/HOYWlPkKdYOhXigq7B0NITbbh62ZBZU5GEkoPi5hQgMDtDL kMHO4f3wsLyzf2vzk1yNRc1rp3nGLO6VyLMqDMctqSsZ3aWKMfcbcDZwJfd17eughyET LTi0ZLNtuUb4qKsZLliVQHCgDvgKLR9cZTGEsovktp5fja57uNreCYThK/2ktrwZZaTU oEoQ== X-Gm-Message-State: AOAM532xF2XJ3lpXCwb7Pp2ZlcZWONTedUwm7cCq3EgfGX6VI9TquQDX Ew6c3FPDkG+q/38AVs03knsRhn/hupXbATk= X-Google-Smtp-Source: ABdhPJyO8mB9+1hjpEI4c2iys3oGoAzHpKFN+ZZyeFAfnRemdzA9D7jOCwPVue2W9QmLyraSfSF4AB2bqc0vndI= X-Received: from tj2.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:187]) (user=tjmercier job=sendgmr) by 2002:a81:ae0c:: with SMTP id m12mr2454548ywh.19.1644596338464; Fri, 11 Feb 2022 08:18:58 -0800 (PST) Date: Fri, 11 Feb 2022 16:18:26 +0000 In-Reply-To: <20220211161831.3493782-1-tjmercier@google.com> Message-Id: <20220211161831.3493782-4-tjmercier@google.com> Mime-Version: 1.0 References: <20220211161831.3493782-1-tjmercier@google.com> X-Mailer: git-send-email 2.35.1.265.g69c8d7142f-goog Subject: [RFC v2 3/6] dmabuf: Use the GPU cgroup charge/uncharge APIs From: "T.J. Mercier" To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Jonathan Corbet , Greg Kroah-Hartman , " =?utf-8?q?Arve_Hj=C3=B8n?= =?utf-8?q?nev=C3=A5g?= " , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Hridya Valsaraju , Suren Baghdasaryan , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Benjamin Gaignard , Liam Mark , Laura Abbott , Brian Starkey , John Stultz , Tejun Heo , Zefan Li , Johannes Weiner Cc: kaleshsingh@google.com, Kenny.Ho@amd.com, "T.J. Mercier" , dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, cgroups@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org This patch uses the GPU cgroup charge/uncharge APIs to charge buffers allocated by any DMA-BUF exporter that exports a buffer with a GPU cgroup device association. By doing so, it becomes possible to track who allocated/exported a DMA-BUF even after the allocating process drops all references to a buffer. From: Hridya Valsaraju Signed-off-by: Hridya Valsaraju Co-developed-by: T.J. Mercier Signed-off-by: T.J. Mercier --- changes in v2 - Move dma-buf cgroup charging/uncharging from a dma_buf_op defined by every heap to a single dma-buf function for all heaps per Daniel Vetter and Christian König. drivers/dma-buf/dma-buf.c | 52 +++++++++++++++++++++++++++++++++++++++ include/linux/dma-buf.h | 20 +++++++++++++-- 2 files changed, 70 insertions(+), 2 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 602b12d7470d..83d0d1b91547 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -56,6 +56,50 @@ static char *dmabuffs_dname(struct dentry *dentry, char *buffer, int buflen) dentry->d_name.name, ret > 0 ? name : ""); } +#ifdef CONFIG_CGROUP_GPU +static inline struct gpucg_device * +exp_info_gpucg_dev(const struct dma_buf_export_info *exp_info) +{ + return exp_info->gpucg_dev; +} + +static bool dmabuf_try_charge(struct dma_buf *dmabuf, + struct gpucg_device *gpucg_dev) +{ + dmabuf->gpucg = gpucg_get(current); + dmabuf->gpucg_dev = gpucg_dev; + if (gpucg_try_charge(dmabuf->gpucg, dmabuf->gpucg_dev, dmabuf->size)) { + gpucg_put(dmabuf->gpucg); + dmabuf->gpucg = NULL; + dmabuf->gpucg_dev = NULL; + return false; + } + return true; +} + +static void dmabuf_uncharge(struct dma_buf *dmabuf) +{ + if (dmabuf->gpucg && dmabuf->gpucg_dev) { + gpucg_uncharge(dmabuf->gpucg, dmabuf->gpucg_dev, dmabuf->size); + gpucg_put(dmabuf->gpucg); + } +} +#else /* CONFIG_CGROUP_GPU */ +static inline struct gpucg_device *exp_info_gpucg_dev( +const struct dma_buf_export_info *exp_info) +{ + return NULL; +} + +static inline bool dmabuf_try_charge(struct dma_buf *dmabuf, + struct gpucg_device *gpucg_dev)) +{ + return false; +} + +static inline void dmabuf_uncharge(struct dma_buf *dmabuf) {} +#endif /* CONFIG_CGROUP_GPU */ + static void dma_buf_release(struct dentry *dentry) { struct dma_buf *dmabuf; @@ -79,6 +123,8 @@ static void dma_buf_release(struct dentry *dentry) if (dmabuf->resv == (struct dma_resv *)&dmabuf[1]) dma_resv_fini(dmabuf->resv); + dmabuf_uncharge(dmabuf); + WARN_ON(!list_empty(&dmabuf->attachments)); module_put(dmabuf->owner); kfree(dmabuf->name); @@ -484,6 +530,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) { struct dma_buf *dmabuf; struct dma_resv *resv = exp_info->resv; + struct gpucg_device *gpucg_dev = exp_info_gpucg_dev(exp_info); struct file *file; size_t alloc_size = sizeof(struct dma_buf); int ret; @@ -534,6 +581,9 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) } dmabuf->resv = resv; + if (gpucg_dev && !dmabuf_try_charge(dmabuf, gpucg_dev)) + goto err_charge; + file = dma_buf_getfile(dmabuf, exp_info->flags); if (IS_ERR(file)) { ret = PTR_ERR(file); @@ -565,6 +615,8 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) file->f_path.dentry->d_fsdata = NULL; fput(file); err_dmabuf: + dmabuf_uncharge(dmabuf); +err_charge: kfree(dmabuf); err_module: module_put(exp_info->owner); diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 7ab50076e7a6..742f29c3daaf 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -13,6 +13,7 @@ #ifndef __DMA_BUF_H__ #define __DMA_BUF_H__ +#include #include #include #include @@ -303,7 +304,7 @@ struct dma_buf { /** * @size: * - * Size of the buffer; invariant over the lifetime of the buffer. + * Size of the buffer in bytes; invariant over the lifetime of the buffer. */ size_t size; @@ -453,6 +454,17 @@ struct dma_buf { struct dma_buf *dmabuf; } *sysfs_entry; #endif + +#ifdef CONFIG_CGROUP_GPU + /** @gpucg: Pointer to the cgroup this buffer currently belongs to. */ + struct gpucg *gpucg; + + /** @gpucg_dev: + * + * Pointer to the cgroup GPU device whence this buffer originates. + */ + struct gpucg_device *gpucg_dev; +#endif }; /** @@ -529,9 +541,10 @@ struct dma_buf_attachment { * @exp_name: name of the exporter - useful for debugging. * @owner: pointer to exporter module - used for refcounting kernel module * @ops: Attach allocator-defined dma buf ops to the new buffer - * @size: Size of the buffer - invariant over the lifetime of the buffer + * @size: Size of the buffer in bytes - invariant over the lifetime of the buffer * @flags: mode flags for the file * @resv: reservation-object, NULL to allocate default one + * @gpucg_dev: pointer to the gpu cgroup device this buffer belongs to * @priv: Attach private data of allocator to this buffer * * This structure holds the information required to export the buffer. Used @@ -544,6 +557,9 @@ struct dma_buf_export_info { size_t size; int flags; struct dma_resv *resv; +#ifdef CONFIG_CGROUP_GPU + struct gpucg_device *gpucg_dev; +#endif void *priv; }; From patchwork Fri Feb 11 16:18:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "T.J. Mercier" X-Patchwork-Id: 541959 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64E7FC433F5 for ; Fri, 11 Feb 2022 16:19:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351426AbiBKQTS (ORCPT ); Fri, 11 Feb 2022 11:19:18 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:47156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351442AbiBKQTP (ORCPT ); Fri, 11 Feb 2022 11:19:15 -0500 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D83A12F7 for ; Fri, 11 Feb 2022 08:19:07 -0800 (PST) Received: by mail-yb1-xb4a.google.com with SMTP id s133-20020a252c8b000000b0062112290d0bso4762318ybs.23 for ; Fri, 11 Feb 2022 08:19:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc:content-transfer-encoding; bh=yvZODKlks7uSqzZPx/QuM2FpvgBeZ2Sk/1s0RF7z1Xc=; b=ec1Yy1HYUYsk8sjBv+NO8SvcoXRcbLd5uiv9OPxDsNNur23ie7DmHnG9pRO3ilNRJc 1WvllX32ogWUY0ES0dpiEE0PkkZAqEtGHDkIOKsW2C7o8MPYg3yfWoNyM+WdEiwbD35T Wm/nnsqgsS4c257blD2h2q3WLvab8g25Dj83ORJVcsTjGYJyVICqcM/zkGknDnaHwtni S4ZDOVi8GlgnNuE1vqJ9LyP4yV9NB3a+ujEPEu7FgVA5ADIEY9Yho6UbQZlXhZiHM4fN WFpGmfjmGs9WnZVI4xN8jGbbfCl8+QIJaWkRzPaFr5hx6+gvkC/2/iIAsFPFyG5TXVMH vNVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc:content-transfer-encoding; bh=yvZODKlks7uSqzZPx/QuM2FpvgBeZ2Sk/1s0RF7z1Xc=; b=of1jwTNWXkS0pemOt0rN0Mfq5jtRCnHObVa0SLbvZs1B3oggEwFOp5nZv8vuSuDelC 1xBG9Zu3UOCq9VFgef1tEAhgnNNFaZA9Jt3LOGy4GMUHW2ECzzRLC7mQ5Jj16n/4QYId x4DpMseQ+KXTJv8zIFIo3FHRjXq7FsaBKAo5AZLyJvTCBKLP27Sufi3O/YNRd7S/L4xY X2/saMOniV3F2K2tqwQJRB5/Uh4Nvf1Er2Cx9F4TlpdTRNL4SQE7Rpa1L8dRbgzxQxxC ph4Hn7PKUNNuUi2SRn8YyrfxB6/8YaSq/ZEwIorwFmQH3n6Aj2ntyaaeXZGnOkmOxAH3 QLTA== X-Gm-Message-State: AOAM530uCm8ll31loX4afzQ9lX6z6HGz9VgPHvlbJU46dW35nw6Y31FG uVnhayy1m+L+71cwkkp89ejgMlIKBmb1S2o= X-Google-Smtp-Source: ABdhPJyzRZpguSr08v/JtkpnGzL6Z+Soi+F7TZB5Jn0SLwqv4tx2BBp/V2mC7+AUgYjetHM8LbPfONmE/Uc6VpY= X-Received: from tj2.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:187]) (user=tjmercier job=sendgmr) by 2002:a81:2d03:: with SMTP id t3mr2496118ywt.215.1644596347024; Fri, 11 Feb 2022 08:19:07 -0800 (PST) Date: Fri, 11 Feb 2022 16:18:28 +0000 In-Reply-To: <20220211161831.3493782-1-tjmercier@google.com> Message-Id: <20220211161831.3493782-6-tjmercier@google.com> Mime-Version: 1.0 References: <20220211161831.3493782-1-tjmercier@google.com> X-Mailer: git-send-email 2.35.1.265.g69c8d7142f-goog Subject: [RFC v2 5/6] dmabuf: Add gpu cgroup charge transfer function From: "T.J. Mercier" To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Jonathan Corbet , Greg Kroah-Hartman , " =?utf-8?q?Arve_Hj=C3=B8n?= =?utf-8?q?nev=C3=A5g?= " , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Hridya Valsaraju , Suren Baghdasaryan , Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Benjamin Gaignard , Liam Mark , Laura Abbott , Brian Starkey , John Stultz , Tejun Heo , Zefan Li , Johannes Weiner Cc: kaleshsingh@google.com, Kenny.Ho@amd.com, "T.J. Mercier" , dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, cgroups@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The dma_buf_charge_transfer function provides a way for processes to transfer charge of a buffer to a different process. This is essential for the cases where a central allocator process does allocations for various subsystems, hands over the fd to the client who requested the memory and drops all references to the allocated memory. From: Hridya Valsaraju Signed-off-by: Hridya Valsaraju Co-developed-by: T.J. Mercier Signed-off-by: T.J. Mercier --- changes in v2 - Move dma-buf cgroup charge transfer from a dma_buf_op defined by every heap to a single dma-buf function for all heaps per Daniel Vetter and Christian König. drivers/dma-buf/dma-buf.c | 48 +++++++++++++++++++++++++++++++++++++++ include/linux/dma-buf.h | 2 ++ 2 files changed, 50 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 83d0d1b91547..55e1b982f840 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1374,6 +1374,54 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map) } EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap, DMA_BUF); +/** + * dma_buf_charge_transfer - Change the GPU cgroup to which the provided dma_buf + * is charged. + * @dmabuf: [in] buffer whose charge will be migrated to a different GPU + * cgroup + * @gpucg: [in] the destination GPU cgroup for dmabuf's charge + * + * Only tasks that belong to the same cgroup the buffer is currently charged to + * may call this function, otherwise it will return -EPERM. + * + * Returns 0 on success, or a negative errno code otherwise. + */ +int dma_buf_charge_transfer(struct dma_buf *dmabuf, struct gpucg *gpucg) +{ +#ifdef CONFIG_CGROUP_GPU + struct gpucg *current_gpucg; + int ret = 0; + + /* + * Verify that the cgroup of the process requesting the transfer is the + * same as the one the buffer is currently charged to. + */ + current_gpucg = gpucg_get(current); + mutex_lock(&dmabuf->lock); + if (current_gpucg != dmabuf->gpucg) { + ret = -EPERM; + goto err; + } + + ret = gpucg_try_charge(gpucg, dmabuf->gpucg_dev, dmabuf->size); + if (ret) + goto err; + + dmabuf->gpucg = gpucg; + + /* uncharge the buffer from the cgroup it's currently charged to. */ + gpucg_uncharge(current_gpucg, dmabuf->gpucg_dev, dmabuf->size); + +err: + mutex_unlock(&dmabuf->lock); + gpucg_put(current_gpucg); + return ret; +#else + return 0; +#endif /* CONFIG_CGROUP_GPU */ +} +EXPORT_SYMBOL_NS_GPL(dma_buf_charge_transfer, DMA_BUF); + #ifdef CONFIG_DEBUG_FS static int dma_buf_debug_show(struct seq_file *s, void *unused) { diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 742f29c3daaf..85c940c08867 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -646,4 +646,6 @@ int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, unsigned long); int dma_buf_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map); void dma_buf_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map); + +int dma_buf_charge_transfer(struct dma_buf *dmabuf, struct gpucg *gpucg); #endif /* __DMA_BUF_H__ */