From patchwork Wed Mar 9 16:52:13 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: 549917 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 BD2B4C41535 for ; Wed, 9 Mar 2022 17:04:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237527AbiCIRFi (ORCPT ); Wed, 9 Mar 2022 12:05:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238939AbiCIREN (ORCPT ); Wed, 9 Mar 2022 12:04:13 -0500 Received: from mail-yw1-x114a.google.com (mail-yw1-x114a.google.com [IPv6:2607:f8b0:4864:20::114a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 06C9019D634 for ; Wed, 9 Mar 2022 08:52:59 -0800 (PST) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-2d7eaa730d9so19165807b3.13 for ; Wed, 09 Mar 2022 08:52:58 -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=iI4tUDTwn0xfO1TZ7KSGGMNGPVBXGkFL9ZZA2HGZghg=; b=X9nwYEkE+WqweWRkaCswHljXOOyceq5HLfdQ2h5VCa5BOpSfIMw+CfpAA66J3vFCf2 DnzE9UQtPeSlxG8o9pCfRDINTOEaiKErWwiNx6nfsrU8fAK+ceVUAS2JHMQD+AbI1jw8 DKHKfrO6gE3o4AH5kcy/Xl/EwVhaZ69JUDtMIle7+RpS6ZagXNItEvUcdhXBvlHBpDzH l3fyRMp2q68ITY/BLJ3Wo+w0+hl26SwqRm77pi7ScO/UoZYTYj89rffHavcoKPlf9R6l UekpqNxes8w71bhq9KSVr3VQ8aymhFsdmRvHHLK69SFOrSb8FaW4zH7Z8JHbBxJrrLrt fypw== 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=iI4tUDTwn0xfO1TZ7KSGGMNGPVBXGkFL9ZZA2HGZghg=; b=RiqXmHSfykNg1dkvr9nKtXQO5vUK2pwqMqhpPhXJNN5SLnd1QNPFGSpBQzjprrUajS iZMLpAVJ2xBm0XF0wjyNyAYTDs8AJexP3vGD6ZArEEzPKshu2imfb5p00oWVaMr8oUKN IokN7f7ruhpwJnh7lBm0DAln1ykD7S8uQoCsKoQMldkzvGvTChmK9MSjNLaM/tMzvhPm nCRu/SSHeRZ0Phb2QveIs+smKegtTvZwCbtldxqvgCEJZajISJwBf8SuyZCYWSGdLCMT l3mt9B5ZjfNLoqjBvZP03PkCyTwqRaFfWk/P1hIPMpSwJcdTLDaxi8KfJ7uW9u5PBdJY R46w== X-Gm-Message-State: AOAM533o6jI6KZKGK3KGSw6/Uk9j42bLrncR51XP0zgxavnv4YC+HxAb OO5EceKJjYViXkj+/CqPvh3kSBJ3FFZYz6A= X-Google-Smtp-Source: ABdhPJyiYlANBNw1jaz9icxi5eZzNkYkUx7cFRm94KikzOWhS/qWZXLh4JI4RlXwg336vFv+RrJsOxkplJS3X04= X-Received: from tj2.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:187]) (user=tjmercier job=sendgmr) by 2002:a81:397:0:b0:2db:645b:c8e5 with SMTP id 145-20020a810397000000b002db645bc8e5mr567278ywd.421.1646844761009; Wed, 09 Mar 2022 08:52:41 -0800 (PST) Date: Wed, 9 Mar 2022 16:52:13 +0000 In-Reply-To: <20220309165222.2843651-1-tjmercier@google.com> Message-Id: <20220309165222.2843651-4-tjmercier@google.com> Mime-Version: 1.0 References: <20220309165222.2843651-1-tjmercier@google.com> X-Mailer: git-send-email 2.35.1.616.g0bdcbb4464-goog Subject: [RFC v3 3/8] 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 , Shuah Khan 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, linux-kselftest@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@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. Originally-by: Hridya Valsaraju Signed-off-by: T.J. Mercier --- v3 changes Use more common dual author commit message format per John Stultz. v2 changes 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; };