Hi,
Le mardi 10 mai 2022 à 23:56 +0000, T.J. Mercier a écrit :
> This patch series revisits the proposal for a GPU cgroup controller to
> track and limit memory allocations by various device/allocator
> subsystems. The patch series also contains a simple prototype to
> illustrate how Android intends to implement DMA-BUF allocator
> attribution using the GPU cgroup controller. The prototype does not
> include resource limit enforcements.
I'm sorry, since I'm not in-depth technically involve. But from reading the
topic I don't understand the bound this creates between DMABuf Heaps and GPU. Is
this an attempt to really track the DMABuf allocated by userland, or just
something for GPU ? What about V4L2 devices ? Any way this can be clarified,
specially what would other subsystem needs to have cgroup DMABuf allocation
controller support ?
>
> Changelog:
> v7:
> Hide gpucg and gpucg_bucket struct definitions per Michal Koutný.
> This means gpucg_register_bucket now returns an internally allocated
> struct gpucg_bucket.
>
> Move all public function documentation to the cgroup_gpu.h header.
>
> Remove comment in documentation about duplicate name rejection which
> is not relevant to cgroups users per Michal Koutný.
>
> v6:
> Move documentation into cgroup-v2.rst per Tejun Heo.
>
> Rename BINDER_FD{A}_FLAG_SENDER_NO_NEED ->
> BINDER_FD{A}_FLAG_XFER_CHARGE per Carlos Llamas.
>
> Return error on transfer failure per Carlos Llamas.
>
> v5:
> Rebase on top of v5.18-rc3
>
> Drop the global GPU cgroup "total" (sum of all device totals) portion
> of the design since there is no currently known use for this per
> Tejun Heo.
>
> Fix commit message which still contained the old name for
> dma_buf_transfer_charge per Michal Koutný.
>
> Remove all GPU cgroup code except what's necessary to support charge transfer
> from dma_buf. Previously charging was done in export, but for non-Android
> graphics use-cases this is not ideal since there may be a delay between
> allocation and export, during which time there is no accounting.
>
> Merge dmabuf: Use the GPU cgroup charge/uncharge APIs patch into
> dmabuf: heaps: export system_heap buffers with GPU cgroup charging as a
> result of above.
>
> 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. This avoids asymmetric management of the gpucg charges.
>
> 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.
>
> Support all strings for gpucg_register_bucket instead of just string
> literals.
>
> Enforce globally unique gpucg_bucket names.
>
> Constrain gpucg_bucket name lengths to 64 bytes.
>
> Append "-heap" to gpucg_bucket names from dmabuf-heaps.
>
> Drop patch 7 from the series, which changed the types of
> binder_transaction_data's sender_pid and sender_euid fields. This was
> done in another commit here:
> https://lore.kernel.org/all/20220210021129.3386083-4-masahiroy@xxxxxxxxxx/
>
> Rename:
> gpucg_try_charge -> gpucg_charge
> find_cg_rpool_locked -> cg_rpool_find_locked
> init_cg_rpool -> cg_rpool_init
> get_cg_rpool_locked -> cg_rpool_get_locked
> "gpu cgroup controller" -> "GPU controller"
> gpucg_device -> gpucg_bucket
> usage -> size
>
> Tests:
> 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.
>
> Tests for both binder_fd_array_object and binder_fd_object.
>
> For binder_utils return error codes instead of
> struct binder{fs}_ctx.
>
> Use ifdef __ANDROID__ to choose platform-dependent temp path instead
> of a runtime fallback.
>
> Ensure binderfs_mntpt ends with a trailing '/' character instead of
> prepending it where used.
>
> v4:
> Skip test if not run as root per Shuah Khan
>
> Add better test logging for abnormal child termination per Shuah Khan
>
> Adjust ordering of charge/uncharge during transfer to avoid potentially
> hitting cgroup limit per Michal Koutný
>
> Adjust gpucg_try_charge critical section for charge transfer functionality
>
> Fix uninitialized return code error for dmabuf_try_charge error case
>
> v3:
> Remove Upstreaming Plan from gpu-cgroup.rst per John Stultz
>
> Use more common dual author commit message format per John Stultz
>
> Remove android from binder changes title per Todd Kjos
>
> Add a kselftest for this new behavior per Greg Kroah-Hartman
>
> Include details on behavior for all combinations of kernel/userspace
> versions in changelog (thanks Suren Baghdasaryan) per Greg Kroah-Hartman.
>
> Fix pid and uid types in binder UAPI header
>
> v2:
> See the previous revision of this change submitted by Hridya Valsaraju
> at: https://lore.kernel.org/all/20220115010622.3185921-1-hridya@xxxxxxxxxx/
>
> 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. Pointers to struct gpucg and struct gpucg_device
> tracking the current associations were added to the dma_buf struct to
> achieve this.
>
> Fix incorrect Kconfig help section indentation per Randy Dunlap.
>
> History of the GPU cgroup controller
> ====================================
> The GPU/DRM cgroup controller came into being when a consensus[1]
> was reached that the resources it tracked were unsuitable to be integrated
> into memcg. Originally, the proposed controller was specific to the DRM
> subsystem and was intended to track GEM buffers and GPU-specific
> resources[2]. In order to help establish a unified memory accounting model
> for all GPU and all related subsystems, Daniel Vetter put forth a
> suggestion to move it out of the DRM subsystem so that it can be used by
> other DMA-BUF exporters as well[3]. This RFC proposes an interface that
> does the same.
>
> [1]: https://patchwork.kernel.org/project/dri-devel/cover/20190501140438.9506-1-brian.welty@xxxxxxxxx/#22624705
> [2]: https://lore.kernel.org/amd-gfx/20210126214626.16260-1-brian.welty@xxxxxxxxx/
> [3]: https://lore.kernel.org/amd-gfx/YCVOl8%2F87bqRSQei@phenom.ffwll.local/
>
> Hridya Valsaraju (3):
> gpu: rfc: Proposal for a GPU cgroup controller
> cgroup: gpu: Add a cgroup controller for allocator attribution of GPU
> memory
> binder: Add flags to relinquish ownership of fds
>
> T.J. Mercier (3):
> dmabuf: heaps: export system_heap buffers with GPU cgroup charging
> dmabuf: Add gpu cgroup charge transfer function
> selftests: Add binder cgroup gpu memory transfer tests
>
> Documentation/admin-guide/cgroup-v2.rst | 23 +
> drivers/android/binder.c | 31 +-
> drivers/dma-buf/dma-buf.c | 80 ++-
> drivers/dma-buf/dma-heap.c | 38 ++
> drivers/dma-buf/heaps/system_heap.c | 28 +-
> include/linux/cgroup_gpu.h | 146 +++++
> include/linux/cgroup_subsys.h | 4 +
> include/linux/dma-buf.h | 49 +-
> include/linux/dma-heap.h | 15 +
> include/uapi/linux/android/binder.h | 23 +-
> init/Kconfig | 7 +
> kernel/cgroup/Makefile | 1 +
> kernel/cgroup/gpu.c | 390 +++++++++++++
> .../selftests/drivers/android/binder/Makefile | 8 +
> .../drivers/android/binder/binder_util.c | 250 +++++++++
> .../drivers/android/binder/binder_util.h | 32 ++
> .../selftests/drivers/android/binder/config | 4 +
> .../binder/test_dmabuf_cgroup_transfer.c | 526 ++++++++++++++++++
> 18 files changed, 1632 insertions(+), 23 deletions(-)
> create mode 100644 include/linux/cgroup_gpu.h
> create mode 100644 kernel/cgroup/gpu.c
> create mode 100644 tools/testing/selftests/drivers/android/binder/Makefile
> create mode 100644 tools/testing/selftests/drivers/android/binder/binder_util.c
> create mode 100644 tools/testing/selftests/drivers/android/binder/binder_util.h
> create mode 100644 tools/testing/selftests/drivers/android/binder/config
> create mode 100644 tools/testing/selftests/drivers/android/binder/test_dmabuf_cgroup_transfer.c
>
