From patchwork Wed Apr 20 23:52:21 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: 12820916 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 C600BC433FE for ; Wed, 20 Apr 2022 23:52:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383311AbiDTXzf (ORCPT ); Wed, 20 Apr 2022 19:55:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33642 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383312AbiDTXzc (ORCPT ); Wed, 20 Apr 2022 19:55:32 -0400 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 C2FFA3E0CA for ; Wed, 20 Apr 2022 16:52:44 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-2eb7d137101so29389387b3.12 for ; Wed, 20 Apr 2022 16:52:44 -0700 (PDT) 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=5E9Rbs7lnkN3+W98JnkIUAPTQ49TUyPznJB6J7YNkeo=; b=SWzxIRgdRQUtqcnezZ1qAW7U1kX7+57LPNNbfRy88rcYumm4IA2OJuYgyyg7UDgn4q MCDVqH2XccdjAMgVUESHKUP693m4h0vVR930REBPdZ6wch5vagUCuVlCO3pq1G/WttSm AKvzWT9Nlv5PQyonszFAMeFGYDERNSYU+Ih9zKKj6eBos5pKLMLliVS1pcZcxSRG7Zrn Oqa7NQcw9kxxBDKs5sWyq9NwhYkTbsb6IZoi2/ioWxpbEzVBB21ZKhOvAmxpG8APKTEc XJCoqM2RQuc7J0nxY6KCv4Zd+OgEpsgHqAse8y3xvopI5/qJepc4wtE8OIQeY+rpy9yg tZlw== 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=5E9Rbs7lnkN3+W98JnkIUAPTQ49TUyPznJB6J7YNkeo=; b=I09ikEN3EJUupsKxKt4jbEeghBAQPA06YBe6pEtlRFqdFd5GKzhk+ljIYvve3GNVF/ YfgInKo+C0L8Y/wi8EBTkP2kKvNsmkdgZIxeuI5CLQUNqfe5ctt8pzoiJDGFVvfHv9au EgszCXzRcqrXrk9o9U76At65iV8srMbQFn6VaaieYdu74qP/Yv67rIGqKgnRRe2MmDg9 Fk2mO9ns6Glz99cVtVbSqtD36q7JMx0xHvp1bRLPe59AdNhkGJwz1YTuxA5EjofdHJJL pw1RJyEWv7CQCEmWc1Cjjyq9JWv1bNU2+9DJchIgblSOP31ny8SMVOfWZBEs1PTfcxb9 zP7w== X-Gm-Message-State: AOAM531YKouUBjnpUVWXjzhty3aUFG9XJaVDN9BKAVjFaY2ugicLHjAS iZBeCBFNalfG1MdUSbPktkrcPIjCBNtfMN8= X-Google-Smtp-Source: ABdhPJw5EwHTC7Q1N41+mc2GzL5YAYNhrKpjL8DBLEBrLVaVg9GO5bS/iutUfeBK1JN69nQVWaRhMs4VIs/z4os= X-Received: from tj.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:53a]) (user=tjmercier job=sendgmr) by 2002:a25:7795:0:b0:645:682a:d56e with SMTP id s143-20020a257795000000b00645682ad56emr3285177ybc.403.1650498763943; Wed, 20 Apr 2022 16:52:43 -0700 (PDT) Date: Wed, 20 Apr 2022 23:52:21 +0000 In-Reply-To: <20220420235228.2767816-1-tjmercier@google.com> Message-Id: <20220420235228.2767816-4-tjmercier@google.com> Mime-Version: 1.0 References: <20220420235228.2767816-1-tjmercier@google.com> X-Mailer: git-send-email 2.36.0.rc0.470.gd361397f0d-goog Subject: [RFC v5 3/6] dmabuf: heaps: export system_heap buffers with GPU cgroup charging From: "T.J. Mercier" To: tjmercier@google.com, daniel@ffwll.ch, tj@kernel.org, Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Benjamin Gaignard , Liam Mark , Laura Abbott , Brian Starkey , John Stultz Cc: hridya@google.com, jstultz@google.com, tkjos@android.com, cmllamas@google.com, surenb@google.com, kaleshsingh@google.com, Kenny.Ho@amd.com, mkoutny@suse.com, skhan@linuxfoundation.org, kernel-team@android.com, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org All DMA heaps now register a new GPU cgroup bucket upon creation, and the system_heap now exports buffers associated with its GPU cgroup bucket for tracking purposes. In order to support GPU cgroup charge transfer on a dma-buf, the current GPU cgroup information must be stored inside the dma-buf struct. For tracked buffers, exporters include the struct gpucg and struct gpucg_bucket pointers in the export info which can later be modified if the charge is migrated to another cgroup. Signed-off-by: Hridya Valsaraju Signed-off-by: T.J. Mercier --- v5 changes Merge dmabuf: Use the GPU cgroup charge/uncharge APIs into this patch. Remove all GPU cgroup code from dma-buf except what's necessary to support charge transfer. Previously charging was done in export, but for non-Android graphics use-cases this is not ideal since there may be a dealy between allocation and export, during which time there is no accounting. Append "-heap" to gpucg_bucket names. Charge on allocation instead of export. This should more closely mirror non-Android use-cases where there is potentially a delay between allocation and export. Put the charge and uncharge code in the same file (system_heap_allocate, system_heap_dma_buf_release) instead of splitting them between the heap and the dma_buf_release. Move no-op code to header file to match other files in the series. v3 changes Use more common dual author commit message format per John Stultz. v2 changes 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 | 19 +++++++++++++ drivers/dma-buf/dma-heap.c | 39 +++++++++++++++++++++++++++ drivers/dma-buf/heaps/system_heap.c | 28 +++++++++++++++++--- include/linux/dma-buf.h | 41 +++++++++++++++++++++++------ include/linux/dma-heap.h | 15 +++++++++++ 5 files changed, 130 insertions(+), 12 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index df23239b04fc..bc89c44bd9b9 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -462,6 +462,24 @@ static struct file *dma_buf_getfile(struct dma_buf *dmabuf, int flags) * &dma_buf_ops. */ +#ifdef CONFIG_CGROUP_GPU +static void dma_buf_set_gpucg(struct dma_buf *dmabuf, const struct dma_buf_export_info *exp) +{ + dmabuf->gpucg = exp->gpucg; + dmabuf->gpucg_bucket = exp->gpucg_bucket; +} + +void dma_buf_exp_info_set_gpucg(struct dma_buf_export_info *exp_info, + struct gpucg *gpucg, + struct gpucg_bucket *gpucg_bucket) +{ + exp_info->gpucg = gpucg; + exp_info->gpucg_bucket = gpucg_bucket; +} +#else +static void dma_buf_set_gpucg(struct dma_buf *dmabuf, struct dma_buf_export_info *exp) {} +#endif + /** * dma_buf_export - Creates a new dma_buf, and associates an anon file * with this buffer, so it can be exported. @@ -527,6 +545,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info) init_waitqueue_head(&dmabuf->poll); dmabuf->cb_in.poll = dmabuf->cb_out.poll = &dmabuf->poll; dmabuf->cb_in.active = dmabuf->cb_out.active = 0; + dma_buf_set_gpucg(dmabuf, exp_info); if (!resv) { resv = (struct dma_resv *)&dmabuf[1]; diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c index 8f5848aa144f..b81015548314 100644 --- a/drivers/dma-buf/dma-heap.c +++ b/drivers/dma-buf/dma-heap.c @@ -7,10 +7,12 @@ */ #include +#include #include #include #include #include +#include #include #include #include @@ -21,6 +23,7 @@ #include #define DEVNAME "dma_heap" +#define HEAP_NAME_SUFFIX "-heap" #define NUM_HEAP_MINORS 128 @@ -31,6 +34,7 @@ * @heap_devt heap device node * @list list head connecting to list of heaps * @heap_cdev heap char device + * @gpucg_bucket gpu cgroup bucket for memory accounting * * Represents a heap of memory from which buffers can be made. */ @@ -41,6 +45,9 @@ struct dma_heap { dev_t heap_devt; struct list_head list; struct cdev heap_cdev; +#ifdef CONFIG_CGROUP_GPU + struct gpucg_bucket gpucg_bucket; +#endif }; static LIST_HEAD(heap_list); @@ -216,6 +223,19 @@ const char *dma_heap_get_name(struct dma_heap *heap) return heap->name; } +/** + * dma_heap_get_gpucg_bucket() - get struct gpucg_bucket for the heap. + * @heap: DMA-Heap to get the gpucg_bucket struct for. + * + * Returns: + * The gpucg_bucket struct for the heap. NULL if the GPU cgroup controller is + * not enabled. + */ +struct gpucg_bucket *dma_heap_get_gpucg_bucket(struct dma_heap *heap) +{ + return &heap->gpucg_bucket; +} + struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) { struct dma_heap *heap, *h, *err_ret; @@ -228,6 +248,12 @@ struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) return ERR_PTR(-EINVAL); } + if (IS_ENABLED(CONFIG_CGROUP_GPU) && strlen(exp_info->name) + strlen(HEAP_NAME_SUFFIX) >= + GPUCG_BUCKET_NAME_MAX_LEN) { + pr_err("dma_heap: Name is too long for GPU cgroup\n"); + return ERR_PTR(-ENAMETOOLONG); + } + if (!exp_info->ops || !exp_info->ops->allocate) { pr_err("dma_heap: Cannot add heap with invalid ops struct\n"); return ERR_PTR(-EINVAL); @@ -253,6 +279,19 @@ struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) heap->ops = exp_info->ops; heap->priv = exp_info->priv; + if (IS_ENABLED(CONFIG_CGROUP_GPU)) { + char gpucg_bucket_name[GPUCG_BUCKET_NAME_MAX_LEN]; + + snprintf(gpucg_bucket_name, sizeof(gpucg_bucket_name), "%s%s", + exp_info->name, HEAP_NAME_SUFFIX); + + ret = gpucg_register_bucket(dma_heap_get_gpucg_bucket(heap), gpucg_bucket_name); + if (ret < 0) { + err_ret = ERR_PTR(ret); + goto err0; + } + } + /* Find unused minor number */ ret = xa_alloc(&dma_heap_minors, &minor, heap, XA_LIMIT(0, NUM_HEAP_MINORS - 1), GFP_KERNEL); diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index fcf836ba9c1f..27f686faef00 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -297,6 +297,11 @@ static void system_heap_dma_buf_release(struct dma_buf *dmabuf) } sg_free_table(table); kfree(buffer); + + if (dmabuf->gpucg && dmabuf->gpucg_bucket) { + gpucg_uncharge(dmabuf->gpucg, dmabuf->gpucg_bucket, dmabuf->size); + gpucg_put(dmabuf->gpucg); + } } static const struct dma_buf_ops system_heap_buf_ops = { @@ -346,11 +351,21 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, struct scatterlist *sg; struct list_head pages; struct page *page, *tmp_page; - int i, ret = -ENOMEM; + struct gpucg *gpucg; + struct gpucg_bucket *gpucg_bucket; + int i, ret; + + gpucg = gpucg_get(current); + gpucg_bucket = dma_heap_get_gpucg_bucket(heap); + ret = gpucg_charge(gpucg, gpucg_bucket, len); + if (ret) + goto put_gpucg; buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); - if (!buffer) - return ERR_PTR(-ENOMEM); + if (!buffer) { + ret = -ENOMEM; + goto uncharge_gpucg; + } INIT_LIST_HEAD(&buffer->attachments); mutex_init(&buffer->lock); @@ -396,6 +411,8 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, exp_info.size = buffer->len; exp_info.flags = fd_flags; exp_info.priv = buffer; + dma_buf_exp_info_set_gpucg(&exp_info, gpucg, gpucg_bucket); + dmabuf = dma_buf_export(&exp_info); if (IS_ERR(dmabuf)) { ret = PTR_ERR(dmabuf); @@ -414,7 +431,10 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, list_for_each_entry_safe(page, tmp_page, &pages, lru) __free_pages(page, compound_order(page)); kfree(buffer); - +uncharge_gpucg: + gpucg_uncharge(gpucg, gpucg_bucket, len); +put_gpucg: + gpucg_put(gpucg); return ERR_PTR(ret); } diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 2097760e8e95..8e7c55c830b3 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 +454,14 @@ struct dma_buf { struct dma_buf *dmabuf; } *sysfs_entry; #endif + +#ifdef CONFIG_CGROUP_GPU + /** @gpucg: Pointer to the GPU cgroup this buffer currently belongs to. */ + struct gpucg *gpucg; + + /* @gpucg_bucket: Pointer to the GPU cgroup bucket whence this buffer originates. */ + struct gpucg_bucket *gpucg_bucket; +#endif }; /** @@ -526,13 +535,15 @@ struct dma_buf_attachment { /** * struct dma_buf_export_info - holds information needed to export a dma_buf - * @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 - * @flags: mode flags for the file - * @resv: reservation-object, NULL to allocate default one - * @priv: Attach private data of allocator to this buffer + * @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 in bytes - invariant over the lifetime of the buffer + * @flags: mode flags for the file + * @resv: reservation-object, NULL to allocate default one + * @priv: Attach private data of allocator to this buffer + * @gpucg: Pointer to GPU cgroup this buffer is charged to, or NULL if not charged + * @gpucg_bucket: Pointer to GPU cgroup bucket this buffer comes from, or NULL if not charged * * This structure holds the information required to export the buffer. Used * with dma_buf_export() only. @@ -545,6 +556,10 @@ struct dma_buf_export_info { int flags; struct dma_resv *resv; void *priv; +#ifdef CONFIG_CGROUP_GPU + struct gpucg *gpucg; + struct gpucg_bucket *gpucg_bucket; +#endif }; /** @@ -630,4 +645,14 @@ int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, unsigned long); int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map); void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map); + +#ifdef CONFIG_CGROUP_GPU +void dma_buf_exp_info_set_gpucg(struct dma_buf_export_info *exp_info, + struct gpucg *gpucg, + struct gpucg_bucket *gpucg_bucket); +#else/* CONFIG_CGROUP_GPU */ +static inline void dma_buf_exp_info_set_gpucg(struct dma_buf_export_info *exp_info, + struct gpucg *gpucg, + struct gpucg_bucket *gpucg_bucket) {} +#endif /* CONFIG_CGROUP_GPU */ #endif /* __DMA_BUF_H__ */ diff --git a/include/linux/dma-heap.h b/include/linux/dma-heap.h index 0c05561cad6e..6321e7636538 100644 --- a/include/linux/dma-heap.h +++ b/include/linux/dma-heap.h @@ -10,6 +10,7 @@ #define _DMA_HEAPS_H #include +#include #include struct dma_heap; @@ -59,6 +60,20 @@ void *dma_heap_get_drvdata(struct dma_heap *heap); */ const char *dma_heap_get_name(struct dma_heap *heap); +#ifdef CONFIG_CGROUP_GPU +/** + * dma_heap_get_gpucg_bucket() - get a pointer to the struct gpucg_bucket for the heap. + * @heap: DMA-Heap to retrieve gpucg_bucket for + * + * Returns: + * The gpucg_bucket struct for the heap. + */ +struct gpucg_bucket *dma_heap_get_gpucg_bucket(struct dma_heap *heap); +#else /* CONFIG_CGROUP_GPU */ +static inline struct gpucg_bucket *dma_heap_get_gpucg_bucket(struct dma_heap *heap) +{ return NULL; } +#endif /* CONFIG_CGROUP_GPU */ + /** * dma_heap_add - adds a heap to dmabuf heaps * @exp_info: information needed to register this heap From patchwork Wed Apr 20 23:52:22 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: 12820917 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 526B0C433EF for ; Wed, 20 Apr 2022 23:52:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383330AbiDTXzn (ORCPT ); Wed, 20 Apr 2022 19:55:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383324AbiDTXzh (ORCPT ); Wed, 20 Apr 2022 19:55:37 -0400 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 C67003DDDE for ; Wed, 20 Apr 2022 16:52:48 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 7-20020a250c07000000b0064137917a4eso2896671ybm.12 for ; Wed, 20 Apr 2022 16:52:48 -0700 (PDT) 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=MFjiN2c4422vfH3G5XH/W0LypfixtCAuep+NsTNNNpQ=; b=O9DK+nzovZ+3UKgC7FIOwT0aMuF2SvsCaF3ZXeSoWy1EhpK0ePx8O/H08V2UqVfgNE UN5jw6LkKrD8qnmQ8yNpabAi8LYhV7IVlIhIyxjzWt3DwY0xQYzoGMBwBTocnz0s4rQ5 ZOKGBkrXwliivGK3Dk1OOuz1iBAnoM5/GpdgoZDvda2LQ+79y+gHEcN4hEcic5si8/tq BgIQcchgyZXlLHtJLZrCzUf6RpuLOSrX5iJi0+Wk0Z3RcDlTPXgAj1jg8XJPOdnclJ4g 1cwxGcpXpjpo6GYI8wlIE6qmSSkrnjGd9jEmnSx6WLGCOCS3QWAGjtKo+pr14uahGroF uPhQ== 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=MFjiN2c4422vfH3G5XH/W0LypfixtCAuep+NsTNNNpQ=; b=p9F5uV/ClkVlAKJEH0wAh1tFLMK5fMWqV7DtFMtebBu/BS25nnW7op7YUxpvAR3BxO 3iDVPnu6dr1KmzcP93MxVMphP+8TJAl837o9oxZJX8ux2a9NLpV0ely4PEvVfU4NK5JO yCUKMgt0PNAdHC33hNuDLvHQgLZ6Hc89KC5EOZHy04kaH3mIxAE/EZ4baVTFFXVJBrE3 zkECeZN0sQZellryjayS9ThlkTCfkU9G3GwT0xLK+fPn/w7QynWmYzQCsw5f7/LAhmnl GRQVpbMT8T8uEWKn0htMPNQ2ahcLC4/ifwYZ3I0Up9Osou0ErCmx2OUf+WVQ8/U4W1XR nvOA== X-Gm-Message-State: AOAM53234OLnZJ7GuVUGIobU+VHb/PFGvBb//+geDjiqz9pQOgTFawbU o5y3On4qqaL8jzilLeQTsJIzwr0SwO33Wds= X-Google-Smtp-Source: ABdhPJwgj/q1pkBqUx+EtmezTxZVaTnub+E1mqztCIeOzLZpLnxcjiZoZHoIs2LVhmVe02tDSbzgfaHA7Of00Js= X-Received: from tj.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:53a]) (user=tjmercier job=sendgmr) by 2002:a0d:f0c3:0:b0:2f4:d291:9dde with SMTP id z186-20020a0df0c3000000b002f4d2919ddemr1882789ywe.437.1650498767961; Wed, 20 Apr 2022 16:52:47 -0700 (PDT) Date: Wed, 20 Apr 2022 23:52:22 +0000 In-Reply-To: <20220420235228.2767816-1-tjmercier@google.com> Message-Id: <20220420235228.2767816-5-tjmercier@google.com> Mime-Version: 1.0 References: <20220420235228.2767816-1-tjmercier@google.com> X-Mailer: git-send-email 2.36.0.rc0.470.gd361397f0d-goog Subject: [RFC v5 4/6] dmabuf: Add gpu cgroup charge transfer function From: "T.J. Mercier" To: tjmercier@google.com, daniel@ffwll.ch, tj@kernel.org, Sumit Semwal , " =?utf-8?q?Christian_K=C3=B6nig?= " , Zefan Li , Johannes Weiner Cc: hridya@google.com, jstultz@google.com, tkjos@android.com, cmllamas@google.com, surenb@google.com, kaleshsingh@google.com, Kenny.Ho@amd.com, mkoutny@suse.com, skhan@linuxfoundation.org, kernel-team@android.com, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The dma_buf_transfer_charge 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. Originally-by: Hridya Valsaraju Signed-off-by: T.J. Mercier --- v5 changes Fix commit message which still contained the old name for dma_buf_transfer_charge per Michal Koutný. Modify the dma_buf_transfer_charge API to accept a task_struct instead of a gpucg. This avoids requiring the caller to manage the refcount of the gpucg upon failure and confusing ownership transfer logic. v4 changes Adjust ordering of charge/uncharge during transfer to avoid potentially hitting cgroup limit per Michal Koutný. v3 changes Use more common dual author commit message format per John Stultz. v2 changes 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 | 57 +++++++++++++++++++++++++++++++++++ include/linux/cgroup_gpu.h | 14 +++++++++ include/linux/dma-buf.h | 6 ++++ kernel/cgroup/gpu.c | 62 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 139 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index bc89c44bd9b9..f3fb844925e2 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1341,6 +1341,63 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map) } EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap, DMA_BUF); +/** + * dma_buf_transfer_charge - 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 + * @target: [in] the task_struct of the destination process for the GPU cgroup 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_transfer_charge(struct dma_buf *dmabuf, struct task_struct *target) +{ + struct gpucg *current_gpucg, *target_gpucg, *to_release; + int ret; + + if (!dmabuf->gpucg || !dmabuf->gpucg_bucket) { + /* This dmabuf is not tracked under GPU cgroup accounting */ + return 0; + } + + current_gpucg = gpucg_get(current); + target_gpucg = gpucg_get(target); + to_release = target_gpucg; + + /* If the source and destination cgroups are the same, don't do anything. */ + if (current_gpucg == target_gpucg) { + ret = 0; + goto skip_transfer; + } + + /* + * Verify that the cgroup of the process requesting the transfer + * is the same as the one the buffer is currently charged to. + */ + mutex_lock(&dmabuf->lock); + if (current_gpucg != dmabuf->gpucg) { + ret = -EPERM; + goto err; + } + + ret = gpucg_transfer_charge( + dmabuf->gpucg, target_gpucg, dmabuf->gpucg_bucket, dmabuf->size); + if (ret) + goto err; + + to_release = dmabuf->gpucg; + dmabuf->gpucg = target_gpucg; + +err: + mutex_unlock(&dmabuf->lock); +skip_transfer: + gpucg_put(current_gpucg); + gpucg_put(to_release); + return ret; +} +EXPORT_SYMBOL_NS_GPL(dma_buf_transfer_charge, DMA_BUF); + #ifdef CONFIG_DEBUG_FS static int dma_buf_debug_show(struct seq_file *s, void *unused) { diff --git a/include/linux/cgroup_gpu.h b/include/linux/cgroup_gpu.h index 4dfe633d6ec7..f5973ef9f926 100644 --- a/include/linux/cgroup_gpu.h +++ b/include/linux/cgroup_gpu.h @@ -83,7 +83,13 @@ static inline struct gpucg *gpucg_parent(struct gpucg *cg) } int gpucg_charge(struct gpucg *gpucg, struct gpucg_bucket *bucket, u64 size); + void gpucg_uncharge(struct gpucg *gpucg, struct gpucg_bucket *bucket, u64 size); + +int gpucg_transfer_charge(struct gpucg *source, + struct gpucg *dest, + struct gpucg_bucket *bucket, + u64 size); int gpucg_register_bucket(struct gpucg_bucket *bucket, const char *name); #else /* CONFIG_CGROUP_GPU */ @@ -118,6 +124,14 @@ static inline void gpucg_uncharge(struct gpucg *gpucg, struct gpucg_bucket *bucket, u64 size) {} +static inline int gpucg_transfer_charge(struct gpucg *source, + struct gpucg *dest, + struct gpucg_bucket *bucket, + u64 size) +{ + return 0; +} + static inline int gpucg_register_bucket(struct gpucg_bucket *bucket, const char *name) {} #endif /* CONFIG_CGROUP_GPU */ #endif /* _CGROUP_GPU_H */ diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 8e7c55c830b3..438ad8577b76 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -650,9 +651,14 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map); void dma_buf_exp_info_set_gpucg(struct dma_buf_export_info *exp_info, struct gpucg *gpucg, struct gpucg_bucket *gpucg_bucket); + +int dma_buf_transfer_charge(struct dma_buf *dmabuf, struct task_struct *target); #else/* CONFIG_CGROUP_GPU */ static inline void dma_buf_exp_info_set_gpucg(struct dma_buf_export_info *exp_info, struct gpucg *gpucg, struct gpucg_bucket *gpucg_bucket) {} + +static inline int dma_buf_transfer_charge(struct dma_buf *dmabuf, struct task_struct *target) +{ return 0; } #endif /* CONFIG_CGROUP_GPU */ #endif /* __DMA_BUF_H__ */ diff --git a/kernel/cgroup/gpu.c b/kernel/cgroup/gpu.c index 34d0a5b85834..7dfbe0fd7e45 100644 --- a/kernel/cgroup/gpu.c +++ b/kernel/cgroup/gpu.c @@ -252,6 +252,68 @@ void gpucg_uncharge(struct gpucg *gpucg, struct gpucg_bucket *bucket, u64 size) css_put(&gpucg->css); } +/** + * gpucg_transfer_charge - Transfer a GPU charge from one cgroup to another. + * + * @source: [in] The GPU cgroup the charge will be transferred from. + * @dest: [in] The GPU cgroup the charge will be transferred to. + * @bucket: [in] The GPU cgroup bucket corresponding to the charge. + * @size: [in] The size of the memory in bytes. + * This size will be rounded up to the nearest page size. + * + * Returns 0 on success, or a negative errno code otherwise. + */ +int gpucg_transfer_charge(struct gpucg *source, + struct gpucg *dest, + struct gpucg_bucket *bucket, + u64 size) +{ + struct page_counter *counter; + u64 nr_pages; + struct gpucg_resource_pool *rp_source, *rp_dest; + int ret = 0; + + nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; + + mutex_lock(&gpucg_mutex); + rp_source = cg_rpool_find_locked(source, bucket); + if (unlikely(!rp_source)) { + ret = -ENOENT; + goto exit_early; + } + + rp_dest = cg_rpool_get_locked(dest, bucket); + if (IS_ERR(rp_dest)) { + ret = PTR_ERR(rp_dest); + goto exit_early; + } + + /* + * First uncharge from the pool it's currently charged to. This ordering avoids double + * charging while the transfer is in progress, which could cause us to hit a limit. + * If the try_charge fails for this transfer, we need to be able to reverse this uncharge, + * so we continue to hold the gpucg_mutex here. + */ + page_counter_uncharge(&rp_source->total, nr_pages); + css_put(&source->css); + + /* Now attempt the new charge */ + if (page_counter_try_charge(&rp_dest->total, nr_pages, &counter)) { + css_get(&dest->css); + } else { + /* + * The new charge failed, so reverse the uncharge from above. This should always + * succeed since charges on source are blocked by gpucg_mutex. + */ + WARN_ON(!page_counter_try_charge(&rp_source->total, nr_pages, &counter)); + css_get(&source->css); + ret = -ENOMEM; + } +exit_early: + mutex_unlock(&gpucg_mutex); + return ret; +} + /** * gpucg_register_bucket - Registers a bucket for memory accounting using the * GPU cgroup controller. From patchwork Wed Apr 20 23:52:23 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: 12820918 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 A4AEBC433F5 for ; Wed, 20 Apr 2022 23:53:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383331AbiDTXzt (ORCPT ); Wed, 20 Apr 2022 19:55:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383312AbiDTXzm (ORCPT ); Wed, 20 Apr 2022 19:55:42 -0400 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 750CE3E0ED for ; Wed, 20 Apr 2022 16:52:52 -0700 (PDT) Received: by mail-yw1-x114a.google.com with SMTP id 00721157ae682-2f198b4e2d1so29162337b3.14 for ; Wed, 20 Apr 2022 16:52:52 -0700 (PDT) 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=/gvN+QpYV7OLh/aEKqlMjgKuKem4NnQTY6rvHp91u8M=; b=sMA3qf7elQFHyscq19H1EpWDhaRa/I7ci48fDvM7QclHAcQqhkQtppdGXfJls2ija/ MvtUn9QqCmeX2jXoh9aXOsqLWBhS95CDoqK3LEcBjVCrsZn3rhJ6gF2q3wsCJy6141rn HXihJHcxQFcvvrhcZnXaBAOeuPSzPOu5OP6IP7nryfGBwy/4jH9/4rQvdFweYWS4ZJ7o iFBWJJboWcdIl0qxM5PnlYsSTP+g7LGwTte4o0TcoqvscLQAxZbvTu5sODCDXJ8Q1tgA rw3i8pgp7ryIMuZezHAtqRxaB/qJTOcE2DcxLzUs4No3oDDwuF4FO1tWii3lpPVJrOBb r2rg== 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=/gvN+QpYV7OLh/aEKqlMjgKuKem4NnQTY6rvHp91u8M=; b=idvMOebIAx0d5T3J588Jx1sPaQIKeCuEYVWENWOhkHTMV4MP8wG8d+EWpMwNQ4YFN3 ZwFO0nbvjP6sd+ofM+pSiM/yiSslDru4KZLiSW3SxYasZmze9Lc8txosr5SU9ScBZAvC CtSzTSbEP3DikR6y0dhNoA4NylaBKCJOVwH60PUa2u2U6wg7/8Pv0nAM4cB5QhsZkXZ/ i9kAEmD1RqZRZ3/945DlT4zHK1OxbNZwWJZyrTrDyWIhfKy7YWZkkm/gSIZfmi6IvhpX LQplrfQD+OqjsHXMA9hXZ3OASKmiFo/UMl4RwkPznGAI/CErzwov5tMH7ax7pi6xlY1f yzTg== X-Gm-Message-State: AOAM530i2TnU3T1jTGyiLwW6818ZzPZ4QfJpjY9M6val5t5WxmicPdiw Y0724K8/D0IpQXTyGKQl9ryhqHwWcQ4NBcE= X-Google-Smtp-Source: ABdhPJxTnlpo/iNagwkjPHbucxYH+CtEj8ohxJdE5GbeBLJ3G2GWRSAkV6DdlP8lN0r7l8RCXlv3YW3DGl+NeWs= X-Received: from tj.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:53a]) (user=tjmercier job=sendgmr) by 2002:a25:2d4d:0:b0:641:d14e:ff85 with SMTP id s13-20020a252d4d000000b00641d14eff85mr21685745ybe.128.1650498771646; Wed, 20 Apr 2022 16:52:51 -0700 (PDT) Date: Wed, 20 Apr 2022 23:52:23 +0000 In-Reply-To: <20220420235228.2767816-1-tjmercier@google.com> Message-Id: <20220420235228.2767816-6-tjmercier@google.com> Mime-Version: 1.0 References: <20220420235228.2767816-1-tjmercier@google.com> X-Mailer: git-send-email 2.36.0.rc0.470.gd361397f0d-goog Subject: [RFC v5 5/6] binder: Add flags to relinquish ownership of fds From: "T.J. Mercier" To: tjmercier@google.com, daniel@ffwll.ch, tj@kernel.org, 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?= " Cc: jstultz@google.com, cmllamas@google.com, kaleshsingh@google.com, Kenny.Ho@amd.com, mkoutny@suse.com, skhan@linuxfoundation.org, kernel-team@android.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Hridya Valsaraju This patch introduces flags BINDER_FD_FLAG_SENDER_NO_NEED, and BINDER_FDA_FLAG_SENDER_NO_NEED that a process sending an individual fd or fd array to another process over binder IPC can set to relinquish ownership of the fds being sent for memory accounting purposes. If the flag is found to be set during the fd or fd array translation and the fd is for a DMA-BUF, the buffer is uncharged from the sender's cgroup and charged to the receiving process's cgroup instead. It is up to the sending process to ensure that it closes the fds regardless of whether the transfer failed or succeeded. Most graphics shared memory allocations in Android are done by the graphics allocator HAL process. On requests from clients, the HAL process allocates memory and sends the fds to the clients over binder IPC. The graphics allocator HAL will not retain any references to the buffers. When the HAL sets *_FLAG_SENDER_NO_NEED for fd arrays holding DMA-BUF fds, or individual fd objects, the gpu cgroup controller will be able to correctly charge the buffers to the client processes instead of the graphics allocator HAL. Since this is a new feature exposed to userspace, the kernel and userspace must be compatible for the accounting to work for transfers. In all cases the allocation and transport of DMA buffers via binder will succeed, but only when both the kernel supports, and userspace depends on this feature will the transfer accounting work. The possible scenarios are detailed below: 1. new kernel + old userspace The kernel supports the feature but userspace does not use it. The old userspace won't mount the new cgroup controller, accounting is not performed, charge is not transferred. 2. old kernel + new userspace The new cgroup controller is not supported by the kernel, accounting is not performed, charge is not transferred. 3. old kernel + old userspace Same as #2 4. new kernel + new userspace Cgroup is mounted, feature is supported and used. Signed-off-by: Hridya Valsaraju Signed-off-by: T.J. Mercier Reviewed-by: Carlos Llamas --- v5 changes Support both binder_fd_array_object and binder_fd_object. This is necessary because new versions of Android will use binder_fd_object instead of binder_fd_array_object, and we need to support both. Use the new, simpler dma_buf_transfer_charge API. v3 changes Remove android from title per Todd Kjos. Use more common dual author commit message format per John Stultz. Include details on behavior for all combinations of kernel/userspace versions in changelog (thanks Suren Baghdasaryan) per Greg Kroah-Hartman. v2 changes 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/android/binder.c | 27 +++++++++++++++++++++++---- drivers/dma-buf/dma-buf.c | 4 ++-- include/linux/dma-buf.h | 2 +- include/uapi/linux/android/binder.h | 23 +++++++++++++++++++---- 4 files changed, 45 insertions(+), 11 deletions(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 8351c5638880..b07d50fe1c80 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -42,6 +42,7 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include #include #include #include @@ -2170,7 +2171,7 @@ static int binder_translate_handle(struct flat_binder_object *fp, return ret; } -static int binder_translate_fd(u32 fd, binder_size_t fd_offset, +static int binder_translate_fd(u32 fd, binder_size_t fd_offset, __u32 flags, struct binder_transaction *t, struct binder_thread *thread, struct binder_transaction *in_reply_to) @@ -2208,6 +2209,23 @@ static int binder_translate_fd(u32 fd, binder_size_t fd_offset, goto err_security; } + if (IS_ENABLED(CONFIG_CGROUP_GPU) && (flags & BINDER_FD_FLAG_SENDER_NO_NEED)) { + if (is_dma_buf_file(file)) { + struct dma_buf *dmabuf = file->private_data; + + ret = dma_buf_transfer_charge(dmabuf, target_proc->tsk); + if (ret) + pr_warn("%d:%d Unable to transfer DMA-BUF fd charge to %d\n", + proc->pid, thread->pid, target_proc->pid); + } else { + binder_user_error( + "%d:%d got transaction with SENDER_NO_NEED for non-dmabuf fd, %d\n", + proc->pid, thread->pid, fd); + ret = -EINVAL; + goto err_noneed; + } + } + /* * Add fixup record for this transaction. The allocation * of the fd in the target needs to be done from a @@ -2226,6 +2244,7 @@ static int binder_translate_fd(u32 fd, binder_size_t fd_offset, return ret; err_alloc: +err_noneed: err_security: fput(file); err_fget: @@ -2528,7 +2547,7 @@ static int binder_translate_fd_array(struct list_head *pf_head, ret = copy_from_user(&fd, sender_ufda_base + sender_uoffset, sizeof(fd)); if (!ret) - ret = binder_translate_fd(fd, offset, t, thread, + ret = binder_translate_fd(fd, offset, fda->flags, t, thread, in_reply_to); if (ret) return ret > 0 ? -EINVAL : ret; @@ -3179,8 +3198,8 @@ static void binder_transaction(struct binder_proc *proc, struct binder_fd_object *fp = to_binder_fd_object(hdr); binder_size_t fd_offset = object_offset + (uintptr_t)&fp->fd - (uintptr_t)fp; - int ret = binder_translate_fd(fp->fd, fd_offset, t, - thread, in_reply_to); + int ret = binder_translate_fd(fp->fd, fd_offset, fp->flags, + t, thread, in_reply_to); fp->pad_binder = 0; if (ret < 0 || diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index f3fb844925e2..36ed6cd4ddcc 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -31,7 +31,6 @@ #include "dma-buf-sysfs-stats.h" -static inline int is_dma_buf_file(struct file *); struct dma_buf_list { struct list_head head; @@ -400,10 +399,11 @@ static const struct file_operations dma_buf_fops = { /* * is_dma_buf_file - Check if struct file* is associated with dma_buf */ -static inline int is_dma_buf_file(struct file *file) +int is_dma_buf_file(struct file *file) { return file->f_op == &dma_buf_fops; } +EXPORT_SYMBOL_NS_GPL(is_dma_buf_file, DMA_BUF); static struct file *dma_buf_getfile(struct dma_buf *dmabuf, int flags) { diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 438ad8577b76..2b9812758fee 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -614,7 +614,7 @@ dma_buf_attachment_is_dynamic(struct dma_buf_attachment *attach) { return !!attach->importer_ops; } - +int is_dma_buf_file(struct file *file); struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, struct device *dev); struct dma_buf_attachment * diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h index 11157fae8a8e..b263cbb603ea 100644 --- a/include/uapi/linux/android/binder.h +++ b/include/uapi/linux/android/binder.h @@ -91,14 +91,14 @@ struct flat_binder_object { /** * struct binder_fd_object - describes a filedescriptor to be fixed up. * @hdr: common header structure - * @pad_flags: padding to remain compatible with old userspace code + * @flags: One or more BINDER_FD_FLAG_* flags * @pad_binder: padding to remain compatible with old userspace code * @fd: file descriptor * @cookie: opaque data, used by user-space */ struct binder_fd_object { struct binder_object_header hdr; - __u32 pad_flags; + __u32 flags; union { binder_uintptr_t pad_binder; __u32 fd; @@ -107,6 +107,17 @@ struct binder_fd_object { binder_uintptr_t cookie; }; +enum { + /** + * @BINDER_FD_FLAG_SENDER_NO_NEED + * + * When set, the sender of a binder_fd_object wishes to relinquish ownership of the fd for + * memory accounting purposes. If the fd is for a DMA-BUF, the buffer is uncharged from the + * sender's cgroup and charged to the receiving process's cgroup instead. + */ + BINDER_FD_FLAG_SENDER_NO_NEED = 0x2000, +}; + /* struct binder_buffer_object - object describing a userspace buffer * @hdr: common header structure * @flags: one or more BINDER_BUFFER_* flags @@ -141,7 +152,7 @@ enum { /* struct binder_fd_array_object - object describing an array of fds in a buffer * @hdr: common header structure - * @pad: padding to ensure correct alignment + * flags: One or more BINDER_FDA_FLAG_* flags * @num_fds: number of file descriptors in the buffer * @parent: index in offset array to buffer holding the fd array * @parent_offset: start offset of fd array in the buffer @@ -162,12 +173,16 @@ enum { */ struct binder_fd_array_object { struct binder_object_header hdr; - __u32 pad; + __u32 flags; binder_size_t num_fds; binder_size_t parent; binder_size_t parent_offset; }; +enum { + BINDER_FDA_FLAG_SENDER_NO_NEED = BINDER_FD_FLAG_SENDER_NO_NEED, +}; + /* * On 64-bit platforms where user code may run in 32-bits the driver must * translate the buffer (and local binder) addresses appropriately.