Linaro-mm-sig May 2025

linaro-mm-sig@lists.linaro.org

27 participants
102 discussions

[PATCH bpf-next v7 0/5] Replace CONFIG_DMABUF_SYSFS_STATS with BPF

by T.J. Mercier

Until CONFIG_DMABUF_SYSFS_STATS was added [1] it was only possible to perform per-buffer accounting with debugfs which is not suitable for production environments. Eventually we discovered the overhead with per-buffer sysfs file creation/removal was significantly impacting allocation and free times, and exacerbated kernfs lock contention. [2] dma_buf_stats_setup() is responsible for 39% of single-page buffer creation duration, or 74% of single-page dma_buf_export() duration when stressing dmabuf allocations and frees. I prototyped a change from per-buffer to per-exporter statistics with a RCU protected list of exporter allocations that accommodates most (but not all) of our use-cases and avoids almost all of the sysfs overhead. While that adds less overhead than per-buffer sysfs, and less even than the maintenance of the dmabuf debugfs_list, it's still *additional* overhead on top of the debugfs_list and doesn't give us per-buffer info. This series uses the existing dmabuf debugfs_list to implement a BPF dmabuf iterator, which adds no overhead to buffer allocation/free and provides per-buffer info. The list has been moved outside of CONFIG_DEBUG_FS scope so that it is always populated. The BPF program loaded by userspace that extracts per-buffer information gets to define its own interface which avoids the lack of ABI stability with debugfs. This will allow us to replace our use of CONFIG_DMABUF_SYSFS_STATS, and the plan is to remove it from the kernel after the next longterm stable release. [1] https://lore.kernel.org/linux-media/20201210044400.1080308-1-hridya@google.… [2] https://lore.kernel.org/all/20220516171315.2400578-1-tjmercier@google.com v1: https://lore.kernel.org/all/20250414225227.3642618-1-tjmercier@google.com v1 -> v2: Make the DMA buffer list independent of CONFIG_DEBUG_FS per Christian König Add CONFIG_DMA_SHARED_BUFFER check to kernel/bpf/Makefile per kernel test robot Use BTF_ID_LIST_SINGLE instead of BTF_ID_LIST_GLOBAL_SINGLE per Song Liu Fixup comment style, mixing code/declarations, and use ASSERT_OK_FD in selftest per Song Liu Add BPF_ITER_RESCHED feature to bpf_dmabuf_reg_info per Alexei Starovoitov Add open-coded iterator and selftest per Alexei Starovoitov Add a second test buffer from the system dmabuf heap to selftests Use the BPF program we'll use in production for selftest per Alexei Starovoitov https://r.android.com/c/platform/system/bpfprogs/+/3616123/2/dmabufIter.c https://r.android.com/c/platform/system/memory/libmeminfo/+/3614259/1/libdm… v2: https://lore.kernel.org/all/20250504224149.1033867-1-tjmercier@google.com v2 -> v3: Rebase onto bpf-next/master Move get_next_dmabuf() into drivers/dma-buf/dma-buf.c, along with the new get_first_dmabuf(). This avoids having to expose the dmabuf list and mutex to the rest of the kernel, and keeps the dmabuf mutex operations near each other in the same file. (Christian König) Add Christian's RB to dma-buf: Rename debugfs symbols Drop RFC: dma-buf: Remove DMA-BUF statistics v3: https://lore.kernel.org/all/20250507001036.2278781-1-tjmercier@google.com v3 -> v4: Fix selftest BPF program comment style (not kdoc) per Alexei Starovoitov Fix dma-buf.c kdoc comment style per Alexei Starovoitov Rename get_first_dmabuf / get_next_dmabuf to dma_buf_iter_begin / dma_buf_iter_next per Christian König Add Christian's RB to bpf: Add dmabuf iterator v4: https://lore.kernel.org/all/20250508182025.2961555-1-tjmercier@google.com v4 -> v5: Add Christian's Acks to all patches Add Song Liu's Acks Move BTF_ID_LIST_SINGLE and DEFINE_BPF_ITER_FUNC closer to usage per Song Liu Fix open-coded iterator comment style per Song Liu Move iterator termination check to its own subtest per Song Liu Rework selftest buffer creation per Song Liu Fix spacing in sanitize_string per BPF CI v5: https://lore.kernel.org/all/20250512174036.266796-1-tjmercier@google.com v5 -> v6: Song Liu: Init test buffer FDs to -1 Zero-init udmabuf_create for future proofing Bail early for iterator fd/FILE creation failure Dereference char ptr to check for NUL in sanitize_string() Move map insertion from create_test_buffers() to test_dmabuf_iter() Add ACK to selftests/bpf: Add test for open coded dmabuf_iter v6: https://lore.kernel.org/all/20250513163601.812317-1-tjmercier@google.com v6 -> v7: Zero uninitialized name bytes following the end of name strings per s390x BPF CI Reorder sanitize_string bounds checks per Song Liu Add Song's Ack to: selftests/bpf: Add test for dmabuf_iter Rebase onto bpf-next/master per BPF CI T.J. Mercier (5): dma-buf: Rename debugfs symbols bpf: Add dmabuf iterator bpf: Add open coded dmabuf iterator selftests/bpf: Add test for dmabuf_iter selftests/bpf: Add test for open coded dmabuf_iter drivers/dma-buf/dma-buf.c | 98 ++++-- include/linux/dma-buf.h | 4 +- kernel/bpf/Makefile | 3 + kernel/bpf/dmabuf_iter.c | 150 +++++++++ kernel/bpf/helpers.c | 5 + .../testing/selftests/bpf/bpf_experimental.h | 5 + tools/testing/selftests/bpf/config | 3 + .../selftests/bpf/prog_tests/dmabuf_iter.c | 285 ++++++++++++++++++ .../testing/selftests/bpf/progs/dmabuf_iter.c | 101 +++++++ 9 files changed, 632 insertions(+), 22 deletions(-) create mode 100644 kernel/bpf/dmabuf_iter.c create mode 100644 tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c create mode 100644 tools/testing/selftests/bpf/progs/dmabuf_iter.c base-commit: 6888a036cfc3d617d0843ecc9bd8504e91fb9de6 -- 2.49.0.1151.ga128411c76-goog

23 hours, 58 minutes

Re: [PATCH v3 01/10] dt-bindings: npu: rockchip,rknn: Add bindings

by Rob Herring (Arm)

On Fri, 16 May 2025 18:53:15 +0200, Tomeu Vizoso wrote: > Add the bindings for the Neural Processing Unit IP from Rockchip. > > v2: > - Adapt to new node structure (one node per core, each with its own > IOMMU) > - Several misc. fixes from Sebastian Reichel > > v3: > - Split register block in its constituent subblocks, and only require > the ones that the kernel would ever use (Nicolas Frattaroli) > - Group supplies (Rob Herring) > - Explain the way in which the top core is special (Rob Herring) > > Signed-off-by: Tomeu Vizoso <tomeu(a)tomeuvizoso.net> > Signed-off-by: Sebastian Reichel <sebastian.reichel(a)collabora.com> > --- > .../bindings/npu/rockchip,rknn-core.yaml | 162 +++++++++++++++++++++ > 1 file changed, 162 insertions(+) > My bot found errors running 'make dt_binding_check' on your patch: yamllint warnings/errors: dtschema/dtc warnings/errors: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/npu/rockchip,rknn-core.yaml: properties:reg-names: 'oneOf' conditional failed, one must be fixed: [{'const': 'pc'}, {'const': 'cna'}, {'const': 'core'}] is too long [{'const': 'pc'}, {'const': 'cna'}, {'const': 'core'}] is too short False schema does not allow 3 1 was expected 3 is greater than the maximum of 2 hint: "minItems" is only needed if less than the "items" list length from schema $id: http://devicetree.org/meta-schemas/items.yaml# /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/npu/rockchip,rknn-core.example.dtb: npu-core@fdab0000 (rockchip,rk3588-rknn-core-top): compatible: 'oneOf' conditional failed, one must be fixed: ['rockchip,rk3588-rknn-core-top', 'rockchip,rknn-core-top'] is too long 'rockchip,rk3588-rknn-core-top' is not one of ['rockchip,rk3588-rknn-core'] from schema $id: http://devicetree.org/schemas/npu/rockchip,rknn-core.yaml# /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/npu/rockchip,rknn-core.example.dtb: npu-core@fdab0000 (rockchip,rk3588-rknn-core-top): reg: [[0, 4255842304, 0, 36864]] is too short from schema $id: http://devicetree.org/schemas/npu/rockchip,rknn-core.yaml# /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/npu/rockchip,rknn-core.example.dtb: npu-core@fdac0000 (rockchip,rk3588-rknn-core): compatible: 'oneOf' conditional failed, one must be fixed: ['rockchip,rk3588-rknn-core', 'rockchip,rknn-core'] is too long 'rockchip,rk3588-rknn-core' is not one of ['rockchip,rk3588-rknn-core-top'] from schema $id: http://devicetree.org/schemas/npu/rockchip,rknn-core.yaml# /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/npu/rockchip,rknn-core.example.dtb: npu-core@fdac0000 (rockchip,rk3588-rknn-core): reg: [[0, 4255907840, 0, 36864]] is too short from schema $id: http://devicetree.org/schemas/npu/rockchip,rknn-core.yaml# doc reference errors (make refcheckdocs): See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20250516-6-1… The base for the series is generally the latest rc1. A different dependency should be noted in *this* patch. If you already ran 'make dt_binding_check' and didn't see the above error(s), then make sure 'yamllint' is installed and dt-schema is up to date: pip3 install dtschema --upgrade Please check and re-submit after running the above command yourself. Note that DT_SCHEMA_FILES can be set to your schema file to speed up checking your schema. However, it must be unset to test all examples with your schema.

1 day, 4 hours

[PATCH v9 0/9] TEE subsystem for protected dma-buf allocations

by Jens Wiklander

Hi, This patch set allocates the protected DMA-bufs from a DMA-heap instantiated from the TEE subsystem. The TEE subsystem handles the DMA-buf allocations since it is the TEE (OP-TEE, AMD-TEE, TS-TEE, or perhaps a future QTEE) which sets up the protection for the memory used for the DMA-bufs. The DMA-heap uses a protected memory pool provided by the backend TEE driver, allowing it to choose how to allocate the protected physical memory. The allocated DMA-bufs must be imported with a new TEE_IOC_SHM_REGISTER_FD before they can be passed as arguments when requesting services from the secure world. Three use-cases (Secure Video Playback, Trusted UI, and Secure Video Recording) have been identified so far to serve as examples of what can be expected. The use-cases have predefined DMA-heap names, "protected,secure-video", "protected,trusted-ui", and "protected,secure-video-record". The backend driver registers protected memory pools for the use-cases it supports. Each use-case has its own protected memory pool since different use-cases require isolation from different parts of the system. A protected memory pool can be based on a static carveout instantiated while probing the TEE backend driver, or dynamically allocated from CMA (dma_alloc_pages()) and made protected as needed by the TEE. This can be tested on a RockPi 4B+ with the following steps: repo init -u https://github.com/jenswi-linaro/manifest.git -m rockpi4.xml \ -b prototype/sdp-v9 repo sync -j8 cd build make toolchains -j$(nproc) make all -j$(nproc) # Copy ../out/rockpi4.img to an SD card and boot the RockPi from that # Connect a monitor to the RockPi # login and at the prompt: gst-launch-1.0 videotestsrc ! \ aesenc key=1f9423681beb9a79215820f6bda73d0f \ iv=e9aa8e834d8d70b7e0d254ff670dd718 serialize-iv=true ! \ aesdec key=1f9423681beb9a79215820f6bda73d0f ! \ kmssink The aesdec module has been hacked to use an OP-TEE TA to decrypt the stream into protected DMA-bufs which are consumed by the kmssink. The primitive QEMU tests from previous patch sets can be tested on RockPi in the same way using: xtest --sdp-basic The primitive tests are tested on QEMU with the following steps: repo init -u https://github.com/jenswi-linaro/manifest.git -m qemu_v8.xml \ -b prototype/sdp-v9 repo sync -j8 cd build make toolchains -j$(nproc) make SPMC_AT_EL=1 all -j$(nproc) make SPMC_AT_EL=1 run-only # login and at the prompt: xtest --sdp-basic The SPMC_AT_EL=1 parameter configures the build with FF-A and an SPMC at S-EL1 inside OP-TEE. The parameter can be changed to SPMC_AT_EL=n to test without FF-A using the original SMC ABI instead. Please remember to do %make arm-tf-clean for TF-A to be rebuilt properly using the new configuration. https://optee.readthedocs.io/en/latest/building/prerequisites.html list dependencies required to build the above. The primitive tests are pretty basic, mostly checking that a Trusted Application in the secure world can access and manipulate the memory. There are also some negative tests for out of bounds buffers, etc. Thanks, Jens Changes since V8: * Using dma_alloc_pages() instead of cma_alloc() so the direct dependency on CMA can be removed together with the patches "cma: export cma_alloc() and cma_release()" and "dma-contiguous: export dma_contiguous_default_area". The patch * Renaming the patch "tee: add tee_shm_alloc_cma_phys_mem()" to "tee: add tee_shm_alloc_dma_mem()" * Setting DMA mask for the OP-TEE TEE device based on input from the secure world instead of relying on the parent device so following patches are removed: "tee: tee_device_alloc(): copy dma_mask from parent device" and "optee: pass parent device to tee_device_alloc()". * Adding Sumit Garg's R-B to "tee: refactor params_from_user()" * In the patch "tee: implement protected DMA-heap", map the physical memory passed to tee_protmem_static_pool_alloc(). Changes since V7: * Adding "dma-buf: dma-heap: export declared functions", "cma: export cma_alloc() and cma_release()", and "dma-contiguous: export dma_contiguous_default_area" to export the symbols needed to keep the TEE subsystem as a load module. * Removing CONFIG_TEE_DMABUF_HEAP and CONFIG_TEE_CMA since they aren't needed any longer. * Addressing review comments in "optee: sync secure world ABI headers" * Better align protected memory pool initialization between the smc-abi and ffa-abi parts of the optee driver. * Removing the patch "optee: account for direction while converting parameters" Changes since V6: * Restricted memory is now known as protected memory since to use the same term as https://docs.vulkan.org/guide/latest/protected.html. Update all patches to consistently use protected memory. * In "tee: implement protected DMA-heap" add the hidden config option TEE_DMABUF_HEAP to tell if the DMABUF_HEAPS functions are available for the TEE subsystem * Adding "tee: refactor params_from_user()", broken out from the patch "tee: new ioctl to a register tee_shm from a dmabuf file descriptor" * For "tee: new ioctl to a register tee_shm from a dmabuf file descriptor": - Update commit message to mention protected memory - Remove and open code tee_shm_get_parent_shm() in param_from_user_memref() * In "tee: add tee_shm_alloc_cma_phys_mem" add the hidden config option TEE_CMA to tell if the CMA functions are available for the TEE subsystem * For "tee: tee_device_alloc(): copy dma_mask from parent device" and "optee: pass parent device to tee_device_alloc", added Reviewed-by: Sumit Garg <sumit.garg(a)kernel.org> Changes since V5: * Removing "tee: add restricted memory allocation" and "tee: add TEE_IOC_RSTMEM_FD_INFO" * Adding "tee: implement restricted DMA-heap", "tee: new ioctl to a register tee_shm from a dmabuf file descriptor", "tee: add tee_shm_alloc_cma_phys_mem()", "optee: pass parent device to tee_device_alloc()", and "tee: tee_device_alloc(): copy dma_mask from parent device" * The two TEE driver OPs "rstmem_alloc()" and "rstmem_free()" are replaced with a struct tee_rstmem_pool abstraction. * Replaced the the TEE_IOC_RSTMEM_ALLOC user space API with the DMA-heap API Changes since V4: * Adding the patch "tee: add TEE_IOC_RSTMEM_FD_INFO" needed by the GStreamer demo * Removing the dummy CPU access and mmap functions from the dma_buf_ops * Fixing a compile error in "optee: FF-A: dynamic restricted memory allocation" reported by kernel test robot <lkp(a)intel.com> Changes since V3: * Make the use_case and flags field in struct tee_shm u32's instead of u16's * Add more description for TEE_IOC_RSTMEM_ALLOC in the header file * Import namespace DMA_BUF in module tee, reported by lkp(a)intel.com * Added a note in the commit message for "optee: account for direction while converting parameters" why it's needed * Factor out dynamic restricted memory allocation from "optee: support restricted memory allocation" into two new commits "optee: FF-A: dynamic restricted memory allocation" and "optee: smc abi: dynamic restricted memory allocation" * Guard CMA usage with #ifdef CONFIG_CMA, effectively disabling dynamic restricted memory allocate if CMA isn't configured Changes since the V2 RFC: * Based on v6.12 * Replaced the flags for SVP and Trusted UID memory with a u32 field with unique id for each use case * Added dynamic allocation of restricted memory pools * Added OP-TEE ABI both with and without FF-A for dynamic restricted memory * Added support for FF-A with FFA_LEND Changes since the V1 RFC: * Based on v6.11 * Complete rewrite, replacing the restricted heap with TEE_IOC_RSTMEM_ALLOC Changes since Olivier's post [2]: * Based on Yong Wu's post [1] where much of dma-buf handling is done in the generic restricted heap * Simplifications and cleanup * New commit message for "dma-buf: heaps: add Linaro restricted dmabuf heap support" * Replaced the word "secure" with "restricted" where applicable Etienne Carriere (1): tee: new ioctl to a register tee_shm from a dmabuf file descriptor Jens Wiklander (8): optee: sync secure world ABI headers dma-buf: dma-heap: export declared functions tee: implement protected DMA-heap tee: refactor params_from_user() tee: add tee_shm_alloc_dma_mem() optee: support protected memory allocation optee: FF-A: dynamic protected memory allocation optee: smc abi: dynamic protected memory allocation drivers/dma-buf/dma-heap.c | 3 + drivers/tee/Makefile | 1 + drivers/tee/optee/Makefile | 1 + drivers/tee/optee/core.c | 10 + drivers/tee/optee/ffa_abi.c | 147 ++++++++- drivers/tee/optee/optee_ffa.h | 27 +- drivers/tee/optee/optee_msg.h | 84 +++++- drivers/tee/optee/optee_private.h | 15 +- drivers/tee/optee/optee_smc.h | 37 ++- drivers/tee/optee/protmem.c | 332 ++++++++++++++++++++ drivers/tee/optee/smc_abi.c | 113 ++++++- drivers/tee/tee_core.c | 155 +++++++--- drivers/tee/tee_heap.c | 487 ++++++++++++++++++++++++++++++ drivers/tee/tee_private.h | 16 + drivers/tee/tee_shm.c | 183 ++++++++++- include/linux/tee_core.h | 71 +++++ include/linux/tee_drv.h | 10 + include/uapi/linux/tee.h | 31 ++ 18 files changed, 1655 insertions(+), 68 deletions(-) create mode 100644 drivers/tee/optee/protmem.c create mode 100644 drivers/tee/tee_heap.c base-commit: b4432656b36e5cc1d50a1f2dc15357543add530e -- 2.43.0

1 day, 6 hours

Re: [PATCH 2/2] dmabuf/heaps: implement DMA_BUF_IOCTL_RW_FILE for system_heap

by Christian König

On 5/22/25 10:02, wangtao wrote: >> -----Original Message----- >> From: Christian König <christian.koenig(a)amd.com> >> Sent: Wednesday, May 21, 2025 7:57 PM >> To: wangtao <tao.wangtao(a)honor.com>; T.J. Mercier >> <tjmercier(a)google.com> >> Cc: sumit.semwal(a)linaro.org; benjamin.gaignard(a)collabora.com; >> Brian.Starkey(a)arm.com; jstultz(a)google.com; linux-media(a)vger.kernel.org; >> dri-devel(a)lists.freedesktop.org; linaro-mm-sig(a)lists.linaro.org; linux- >> kernel(a)vger.kernel.org; wangbintian(BintianWang) >> <bintian.wang(a)honor.com>; yipengxiang <yipengxiang(a)honor.com>; liulu >> 00013167 <liulu.liu(a)honor.com>; hanfeng 00012985 <feng.han(a)honor.com>; >> amir73il(a)gmail.com >> Subject: Re: [PATCH 2/2] dmabuf/heaps: implement >> DMA_BUF_IOCTL_RW_FILE for system_heap >> >> On 5/21/25 12:25, wangtao wrote: >>> [wangtao] I previously explained that >>> read/sendfile/splice/copy_file_range >>> syscalls can't achieve dmabuf direct IO zero-copy. >> >> And why can't you work on improving those syscalls instead of creating a new >> IOCTL? >> > [wangtao] As I mentioned in previous emails, these syscalls cannot > achieve dmabuf zero-copy due to technical constraints. Yeah, and why can't you work on removing those technical constrains? What is blocking you from improving the sendfile system call or proposing a patch to remove the copy_file_range restrictions? Regards, Christian. Could you > specify the technical points, code, or principles that need > optimization? > > Let me explain again why these syscalls can't work: > 1. read() syscall > - dmabuf fops lacks read callback implementation. Even if implemented, > file_fd info cannot be transferred > - read(file_fd, dmabuf_ptr, len) with remap_pfn_range-based mmap > cannot access dmabuf_buf pages, forcing buffer-mode reads > > 2. sendfile() syscall > - Requires CPU copy from page cache to memory file(tmpfs/shmem): > [DISK] --DMA--> [page cache] --CPU copy--> [MEMORY file] > - CPU overhead (both buffer/direct modes involve copies): > 55.08% do_sendfile > |- 55.08% do_splice_direct > |-|- 55.08% splice_direct_to_actor > |-|-|- 22.51% copy_splice_read > |-|-|-|- 16.57% f2fs_file_read_iter > |-|-|-|-|- 15.12% __iomap_dio_rw > |-|-|- 32.33% direct_splice_actor > |-|-|-|- 32.11% iter_file_splice_write > |-|-|-|-|- 28.42% vfs_iter_write > |-|-|-|-|-|- 28.42% do_iter_write > |-|-|-|-|-|-|- 28.39% shmem_file_write_iter > |-|-|-|-|-|-|-|- 24.62% generic_perform_write > |-|-|-|-|-|-|-|-|- 18.75% __pi_memmove > > 3. splice() requires one end to be a pipe, incompatible with regular files or dmabuf. > > 4. copy_file_range() > - Blocked by cross-FS restrictions (Amir's commit 868f9f2f8e00) > - Even without this restriction, Even without restrictions, implementing > the copy_file_range callback in dmabuf fops would only allow dmabuf read > from regular files. This is because copy_file_range relies on > file_out->f_op->copy_file_range, which cannot support dmabuf write > operations to regular files. > > Test results confirm these limitations: > T.J. Mercier's 1G from ext4 on 6.12.20 | read/sendfile (ms) w/ 3 > drop_caches > ------------------------|------------------- > udmabuf buffer read | 1210 > udmabuf direct read | 671 > udmabuf buffer sendfile | 1096 > udmabuf direct sendfile | 2340 > > My 3GHz CPU tests (cache cleared): > Method | alloc | read | vs. (%) > ----------------------------------------------- > udmabuf buffer read | 135 | 546 | 180% > udmabuf direct read | 159 | 300 | 99% > udmabuf buffer sendfile | 134 | 303 | 100% > udmabuf direct sendfile | 141 | 912 | 301% > dmabuf buffer read | 22 | 362 | 119% > my patch direct read | 29 | 265 | 87% > > My 1GHz CPU tests (cache cleared): > Method | alloc | read | vs. (%) > ----------------------------------------------- > udmabuf buffer read | 552 | 2067 | 198% > udmabuf direct read | 540 | 627 | 60% > udmabuf buffer sendfile | 497 | 1045 | 100% > udmabuf direct sendfile | 527 | 2330 | 223% > dmabuf buffer read | 40 | 1111 | 106% > patch direct read | 44 | 310 | 30% > > Test observations align with expectations: > 1. dmabuf buffer read requires slow CPU copies > 2. udmabuf direct read achieves zero-copy but has page retrieval > latency from vaddr > 3. udmabuf buffer sendfile suffers CPU copy overhead > 4. udmabuf direct sendfile combines CPU copies with frequent DMA > operations due to small pipe buffers > 5. dmabuf buffer read also requires CPU copies > 6. My direct read patch enables zero-copy with better performance > on low-power CPUs > 7. udmabuf creation time remains problematic (as you’ve noted). > >>> My focus is enabling dmabuf direct I/O for [regular file] <--DMA--> >>> [dmabuf] zero-copy. >> >> Yeah and that focus is wrong. You need to work on a general solution to the >> issue and not specific to your problem. >> >>> Any API achieving this would work. Are there other uAPIs you think >>> could help? Could you recommend experts who might offer suggestions? >> >> Well once more: Either work on sendfile or copy_file_range or eventually >> splice to make it what you want to do. >> >> When that is done we can discuss with the VFS people if that approach is >> feasible. >> >> But just bypassing the VFS review by implementing a DMA-buf specific IOCTL >> is a NO-GO. That is clearly not something you can do in any way. > [wangtao] The issue is that only dmabuf lacks Direct I/O zero-copy support. Tmpfs/shmem > already work with Direct I/O zero-copy. As explained, existing syscalls or > generic methods can't enable dmabuf direct I/O zero-copy, which is why I > propose adding an IOCTL command. > > I respect your perspective. Could you clarify specific technical aspects, > code requirements, or implementation principles for modifying sendfile() > or copy_file_range()? This would help advance our discussion. > > Thank you for engaging in this dialogue. > >> >> Regards, >> Christian.

1 day, 11 hours

[PATCH v2 00/12] Rust abstractions for shmem-backed GEM objects

by Lyude Paul

This is the next version of the shmem backed GEM objects series originally from Asahi, previously posted by Daniel Almeida. Along with bindings for shmem backed GEM objects, it also adds a few features that various users like Tyr and Asahi are interested in: * The ability to pass custom arguments to new GEM objects (needed by Tyr) * OpaqueObject (to enable the use of custom private GEM objects, which I believe asahi wanted) And replaces some of the hand-rolled API bindings (sg_table mainly) with some of the WIP patch series for adding kernel-wide bindings. It also addresses the comments from the code review of the last version of this patch series. Currently doesn't apply on an upstream branch, but should very soon as all of the dependencies in this series are on a mailing list already. The current branch this can be applied on top of is here: https://gitlab.freedesktop.org/lyudess/linux/-/commits/rust%2Fgem-shmem-base Which is based on top of nova/nova-next with the following patch series applied: * My (hopefully final) gem bindings cleanup: https://lkml.org/lkml/2025/5/20/1541 * Benno's derive Zeroable series: https://lkml.org/lkml/2025/5/20/1446 * Abdiel's sg_table series: https://lwn.net/Articles/1020986/ Also, there is one FIXES patch on top of Abdiel's work to fix some iterator bugs. These fixes have already been mentioned on the mailing list and should not be needed for their V2 version Asahi Lina (3): rust: helpers: Add bindings/wrappers for dma_resv_lock rust: drm: gem: shmem: Add DRM shmem helper abstraction rust: drm: gem: shmem: Add share_dma_resv to ObjectConfig Lyude Paul (9): rust: drm: gem: Add raw_dma_resv() function drm/gem/shmem: Extract drm_gem_shmem_init() from drm_gem_shmem_create() drm/gem/shmem: Extract drm_gem_shmem_release() from drm_gem_shmem_free() rust: gem: Introduce BaseDriverObject::Args rust: drm: gem: Add OpaqueObject rust: drm: gem: Introduce OwnedSGTable rust: Add dma_buf stub bindings rust: drm: gem: Add export() callback rust: drm: gem: Add BaseObject::prime_export() drivers/gpu/drm/drm_gem_shmem_helper.c | 98 +++++-- drivers/gpu/drm/nova/gem.rs | 6 +- include/drm/drm_gem_shmem_helper.h | 2 + rust/bindings/bindings_helper.h | 4 + rust/helpers/dma-resv.c | 13 + rust/helpers/drm.c | 48 +++- rust/helpers/helpers.c | 1 + rust/kernel/dma_buf.rs | 39 +++ rust/kernel/drm/gem/mod.rs | 187 ++++++++++++- rust/kernel/drm/gem/shmem.rs | 370 +++++++++++++++++++++++++ rust/kernel/lib.rs | 1 + 11 files changed, 727 insertions(+), 42 deletions(-) create mode 100644 rust/helpers/dma-resv.c create mode 100644 rust/kernel/dma_buf.rs create mode 100644 rust/kernel/drm/gem/shmem.rs -- 2.49.0

1 day, 14 hours

Re: [PATCH v3 4/5] drm/panfrost: show device-wide list of DRM GEM objects over DebugFS

by Steven Price

On 20/05/2025 18:44, Adrián Larumbe wrote: > This change is essentially a Panfrost port of commit a3707f53eb3f > ("drm/panthor: show device-wide list of DRM GEM objects over DebugFS"). > > The DebugFS file is almost the same as in Panthor, minus the GEM object > usage flags, since Panfrost has no kernel-only BO's. > > Two additional GEM state flags which are displayed but aren't relevant > to Panthor are 'Purged' and 'Purgeable', since Panfrost implements an > explicit shrinker and a madvise ioctl to flag objects as reclaimable. > > Signed-off-by: Adrián Larumbe <adrian.larumbe(a)collabora.com> Reviewed-by: Steven Price <steven.price(a)arm.com> > --- > drivers/gpu/drm/panfrost/panfrost_device.c | 5 + > drivers/gpu/drm/panfrost/panfrost_device.h | 15 +++ > drivers/gpu/drm/panfrost/panfrost_drv.c | 35 ++++++ > drivers/gpu/drm/panfrost/panfrost_gem.c | 134 +++++++++++++++++++++ > drivers/gpu/drm/panfrost/panfrost_gem.h | 47 ++++++++ > 5 files changed, 236 insertions(+) > > diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c > index 5d35076b2e6d..04bec27449cb 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_device.c > +++ b/drivers/gpu/drm/panfrost/panfrost_device.c > @@ -209,6 +209,11 @@ int panfrost_device_init(struct panfrost_device *pfdev) > > spin_lock_init(&pfdev->cycle_counter.lock); > > +#ifdef CONFIG_DEBUG_FS > + mutex_init(&pfdev->debugfs.gems_lock); > + INIT_LIST_HEAD(&pfdev->debugfs.gems_list); > +#endif > + > err = panfrost_pm_domain_init(pfdev); > if (err) > return err; > diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h > index dcff70f905cd..077525a3ad68 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_device.h > +++ b/drivers/gpu/drm/panfrost/panfrost_device.h > @@ -111,6 +111,17 @@ struct panfrost_compatible { > u8 gpu_quirks; > }; > > +/** > + * struct panfrost_device_debugfs - Device-wide DebugFS tracking structures > + */ > +struct panfrost_device_debugfs { > + /** @gems_list: Device-wide list of GEM objects owned by at least one file. */ > + struct list_head gems_list; > + > + /** @gems_lock: Serializes access to the device-wide list of GEM objects. */ > + struct mutex gems_lock; > +}; > + > struct panfrost_device { > struct device *dev; > struct drm_device *ddev; > @@ -164,6 +175,10 @@ struct panfrost_device { > atomic_t use_count; > spinlock_t lock; > } cycle_counter; > + > +#ifdef CONFIG_DEBUG_FS > + struct panfrost_device_debugfs debugfs; > +#endif > }; > > struct panfrost_mmu { > diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c > index 179fbaa1cd0c..f576cb215898 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_drv.c > +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c > @@ -13,6 +13,7 @@ > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > #include <drm/panfrost_drm.h> > +#include <drm/drm_debugfs.h> > #include <drm/drm_drv.h> > #include <drm/drm_ioctl.h> > #include <drm/drm_syncobj.h> > @@ -659,6 +660,37 @@ static const struct file_operations panfrost_drm_driver_fops = { > .show_fdinfo = drm_show_fdinfo, > }; > > +#ifdef CONFIG_DEBUG_FS > +static int panthor_gems_show(struct seq_file *m, void *data) > +{ > + struct drm_info_node *node = m->private; > + struct drm_device *dev = node->minor->dev; > + struct panfrost_device *pfdev = dev->dev_private; > + > + panfrost_gem_debugfs_print_bos(pfdev, m); > + > + return 0; > +} > + > +static struct drm_info_list panthor_debugfs_list[] = { > + {"gems", panthor_gems_show, 0, NULL}, > +}; > + > +static int panthor_gems_debugfs_init(struct drm_minor *minor) > +{ > + drm_debugfs_create_files(panthor_debugfs_list, > + ARRAY_SIZE(panthor_debugfs_list), > + minor->debugfs_root, minor); > + > + return 0; > +} > + > +static void panfrost_debugfs_init(struct drm_minor *minor) > +{ > + panthor_gems_debugfs_init(minor); > +} > +#endif > + > /* > * Panfrost driver version: > * - 1.0 - initial interface > @@ -683,6 +715,9 @@ static const struct drm_driver panfrost_drm_driver = { > > .gem_create_object = panfrost_gem_create_object, > .gem_prime_import_sg_table = panfrost_gem_prime_import_sg_table, > +#ifdef CONFIG_DEBUG_FS > + .debugfs_init = panfrost_debugfs_init, > +#endif > }; > > static int panfrost_probe(struct platform_device *pdev) > diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panfrost/panfrost_gem.c > index 04483d5fb45d..bb73f2a68a12 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_gem.c > +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c > @@ -12,6 +12,36 @@ > #include "panfrost_gem.h" > #include "panfrost_mmu.h" > > +#ifdef CONFIG_DEBUG_FS > +static void panfrost_gem_debugfs_bo_add(struct panfrost_device *pfdev, > + struct panfrost_gem_object *bo) > +{ > + bo->debugfs.creator.tgid = current->group_leader->pid; > + get_task_comm(bo->debugfs.creator.process_name, current->group_leader); > + > + mutex_lock(&pfdev->debugfs.gems_lock); > + list_add_tail(&bo->debugfs.node, &pfdev->debugfs.gems_list); > + mutex_unlock(&pfdev->debugfs.gems_lock); > +} > + > +static void panfrost_gem_debugfs_bo_rm(struct panfrost_gem_object *bo) > +{ > + struct panfrost_device *pfdev = bo->base.base.dev->dev_private; > + > + if (list_empty(&bo->debugfs.node)) > + return; > + > + mutex_lock(&pfdev->debugfs.gems_lock); > + list_del_init(&bo->debugfs.node); > + mutex_unlock(&pfdev->debugfs.gems_lock); > +} > +#else > +static void panfrost_gem_debugfs_bo_add(struct panfrost_device *pfdev, > + struct panfrost_gem_object *bo) > +{} > +static void panfrost_gem_debugfs_bo_rm(struct panfrost_gem_object *bo) {} > +#endif > + > /* Called DRM core on the last userspace/kernel unreference of the > * BO. > */ > @@ -37,6 +67,7 @@ static void panfrost_gem_free_object(struct drm_gem_object *obj) > WARN_ON_ONCE(!list_empty(&bo->mappings.list)); > > kfree_const(bo->label.str); > + panfrost_gem_debugfs_bo_rm(bo); > mutex_destroy(&bo->label.lock); > > if (bo->sgts) { > @@ -266,6 +297,8 @@ struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t > obj->base.map_wc = !pfdev->coherent; > mutex_init(&obj->label.lock); > > + panfrost_gem_debugfs_bo_add(pfdev, obj); > + > return &obj->base.base; > } > > @@ -354,3 +387,104 @@ panfrost_gem_internal_set_label(struct drm_gem_object *obj, const char *label) > > panfrost_gem_set_label(obj, str); > } > + > +#ifdef CONFIG_DEBUG_FS > +struct gem_size_totals { > + size_t size; > + size_t resident; > + size_t reclaimable; > +}; > + > +struct flag_def { > + u32 flag; > + const char *name; > +}; > + > +static void panfrost_gem_debugfs_print_flag_names(struct seq_file *m) > +{ > + int len; > + int i; > + > + static const struct flag_def gem_state_flags_names[] = { > + {PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED, "imported"}, > + {PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED, "exported"}, > + {PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED, "purged"}, > + {PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE, "purgeable"}, > + }; > + > + seq_puts(m, "GEM state flags: "); > + for (i = 0, len = ARRAY_SIZE(gem_state_flags_names); i < len; i++) { > + seq_printf(m, "%s (0x%x)%s", gem_state_flags_names[i].name, > + gem_state_flags_names[i].flag, (i < len - 1) ? ", " : "\n\n"); > + } > +} > + > +static void panfrost_gem_debugfs_bo_print(struct panfrost_gem_object *bo, > + struct seq_file *m, > + struct gem_size_totals *totals) > +{ > + unsigned int refcount = kref_read(&bo->base.base.refcount); > + char creator_info[32] = {}; > + size_t resident_size; > + u32 gem_state_flags = 0; > + > + /* Skip BOs being destroyed. */ > + if (!refcount) > + return; > + > + resident_size = bo->base.pages ? bo->base.base.size : 0; > + > + snprintf(creator_info, sizeof(creator_info), > + "%s/%d", bo->debugfs.creator.process_name, bo->debugfs.creator.tgid); > + seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd0x%-16lx", > + creator_info, > + bo->base.base.name, > + refcount, > + bo->base.base.size, > + resident_size, > + drm_vma_node_start(&bo->base.base.vma_node)); > + > + if (bo->base.base.import_attach) > + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED; > + if (bo->base.base.dma_buf) > + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED; > + > + if (bo->base.madv < 0) > + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED; > + else if (bo->base.madv > 0) > + gem_state_flags |= PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE; > + > + seq_printf(m, "0x%-10x", gem_state_flags); > + > + scoped_guard(mutex, &bo->label.lock) { > + seq_printf(m, "%s\n", bo->label.str ? : ""); > + } > + > + totals->size += bo->base.base.size; > + totals->resident += resident_size; > + if (bo->base.madv > 0) > + totals->reclaimable += resident_size; > +} > + > +void panfrost_gem_debugfs_print_bos(struct panfrost_device *pfdev, > + struct seq_file *m) > +{ > + struct gem_size_totals totals = {0}; > + struct panfrost_gem_object *bo; > + > + panfrost_gem_debugfs_print_flag_names(m); > + > + seq_puts(m, "created-by global-name refcount size resident-size file-offset state label\n"); > + seq_puts(m, "-----------------------------------------------------------------------------------------------------------------------------------\n"); > + > + scoped_guard(mutex, &pfdev->debugfs.gems_lock) { > + list_for_each_entry(bo, &pfdev->debugfs.gems_list, debugfs.node) { > + panfrost_gem_debugfs_bo_print(bo, m, &totals); > + } > + } > + > + seq_puts(m, "===================================================================================================================================\n"); > + seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n", > + totals.size, totals.resident, totals.reclaimable); > +} > +#endif > diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h b/drivers/gpu/drm/panfrost/panfrost_gem.h > index 3d87c41ad09d..8de3e76f2717 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_gem.h > +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h > @@ -8,9 +8,47 @@ > #include <drm/drm_mm.h> > > struct panfrost_mmu; > +struct panfrost_device; > > #define PANFROST_BO_LABEL_MAXLEN 4096 > > +enum panfrost_debugfs_gem_state_flags { > + /** @PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED: GEM BO is PRIME imported. */ > + PANFROST_DEBUGFS_GEM_STATE_FLAG_IMPORTED = BIT(0), > + > + /** @PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED: GEM BO is PRIME exported. */ > + PANFROST_DEBUGFS_GEM_STATE_FLAG_EXPORTED = BIT(1), > + > + /** @PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED: GEM BO was reclaimed by the shrinker. */ > + PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGED = BIT(2), > + > + /** > + * @PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE: GEM BO pages were marked as no longer > + * needed by UM and can be reclaimed by the shrinker. > + */ > + PANFROST_DEBUGFS_GEM_STATE_FLAG_PURGEABLE = BIT(3), > +}; > + > +/** > + * struct panfrost_gem_debugfs - GEM object's DebugFS list information > + */ > +struct panfrost_gem_debugfs { > + /** > + * @node: Node used to insert the object in the device-wide list of > + * GEM objects, to display information about it through a DebugFS file. > + */ > + struct list_head node; > + > + /** @creator: Information about the UM process which created the GEM. */ > + struct { > + /** @creator.process_name: Group leader name in owning thread's process */ > + char process_name[TASK_COMM_LEN]; > + > + /** @creator.tgid: PID of the thread's group leader within its process */ > + pid_t tgid; > + } creator; > +}; > + > struct panfrost_gem_object { > struct drm_gem_shmem_object base; > struct sg_table *sgts; > @@ -59,6 +97,10 @@ struct panfrost_gem_object { > > bool noexec :1; > bool is_heap :1; > + > +#ifdef CONFIG_DEBUG_FS > + struct panfrost_gem_debugfs debugfs; > +#endif > }; > > struct panfrost_gem_mapping { > @@ -108,4 +150,9 @@ void panfrost_gem_shrinker_cleanup(struct drm_device *dev); > void panfrost_gem_set_label(struct drm_gem_object *obj, const char *label); > void panfrost_gem_internal_set_label(struct drm_gem_object *obj, const char *label); > > +#ifdef CONFIG_DEBUG_FS > +void panfrost_gem_debugfs_print_bos(struct panfrost_device *pfdev, > + struct seq_file *m); > +#endif > + > #endif /* __PANFROST_GEM_H__ */

2 days, 7 hours

Re: [PATCH v2 2/2] dma-buf: heaps: Give default CMA heap a fixed name

by Maxime Ripard

Hi Jared, On Thu, Apr 24, 2025 at 09:11:24AM -0700, Jared Kangas wrote: > > > struct cma_heap { > > > struct dma_heap *heap; > > > @@ -394,15 +395,26 @@ static int __init __add_cma_heap(struct cma *cma, const char *name) > > > static int __init add_default_cma_heap(void) > > > { > > > struct cma *default_cma = dev_get_cma_area(NULL); > > > + const char *legacy_cma_name; > > > int ret; > > > > > > if (!default_cma) > > > return 0; > > > > > > - ret = __add_cma_heap(default_cma, cma_get_name(default_cma)); > > > + ret = __add_cma_heap(default_cma, DEFAULT_CMA_NAME); > > > if (ret) > > > return ret; > > > > > > + legacy_cma_name = cma_get_name(default_cma); > > > + > > > + if (IS_ENABLED(CONFIG_DMABUF_HEAPS_CMA_LEGACY) && > > > + strcmp(legacy_cma_name, DEFAULT_CMA_NAME)) { > > > + ret = __add_cma_heap(default_cma, legacy_cma_name); > > > + if (ret) > > > + pr_warn("cma_heap: failed to add legacy heap: %pe\n", > > > + ERR_PTR(-ret)); > > > + } > > > + > > > > It would also simplify this part, since you would always create the legacy heap. > > By "always", do you mean removing the strcmp? I added this to guard > against cases where the devicetree node's name clashed with the default > name, given that the DT name isn't necessarily restricted to one of the > current names in use ("linux,cma" or "default-pool"). It seems like the > strcmp would be relevant regardless of the naming choice, but if this is > overly cautious, I can remove it in v3. That's not overly cautious, that's something I overlooked :) You're totally right that we should check for that. We should probably add a more specific error message in that case though Maxime

2 days, 7 hours

Re: [PATCH 2/2] dmabuf/heaps: implement DMA_BUF_IOCTL_RW_FILE for system_heap

by Christian König

On 5/21/25 12:25, wangtao wrote: > [wangtao] I previously explained that read/sendfile/splice/copy_file_range > syscalls can't achieve dmabuf direct IO zero-copy. And why can't you work on improving those syscalls instead of creating a new IOCTL? > My focus is enabling dmabuf direct I/O for [regular file] <--DMA--> [dmabuf] > zero-copy. Yeah and that focus is wrong. You need to work on a general solution to the issue and not specific to your problem. > Any API achieving this would work. Are there other uAPIs you think > could help? Could you recommend experts who might offer suggestions? Well once more: Either work on sendfile or copy_file_range or eventually splice to make it what you want to do. When that is done we can discuss with the VFS people if that approach is feasible. But just bypassing the VFS review by implementing a DMA-buf specific IOCTL is a NO-GO. That is clearly not something you can do in any way. Regards, Christian.

2 days, 11 hours

Re: [PATCH 2/2] dmabuf/heaps: implement DMA_BUF_IOCTL_RW_FILE for system_heap

by Christian König

On 5/21/25 06:17, wangtao wrote: >>> Reducing CPU overhead/power consumption is critical for mobile devices. >>> We need simpler and more efficient dmabuf direct I/O support. >>> >>> As Christian evaluated sendfile performance based on your data, could >>> you confirm whether the cache was cleared? If not, please share the >>> post-cache-clearing test data. Thank you for your support. >> >> Yes sorry, I was out yesterday riding motorcycles. I did not clear the cache for >> the buffered reads, I didn't realize you had. The IO plus the copy certainly >> explains the difference. >> >> Your point about the unlikelihood of any of that data being in the cache also >> makes sense. > [wangtao] Thank you for testing and clarifying. > >> >> I'm not sure it changes anything about the ioctl approach though. >> Another way to do this would be to move the (optional) support for direct IO >> into the exporter via dma_buf_fops and dma_buf_ops. Then normal read() >> syscalls would just work for buffers that support them. >> I know that's more complicated, but at least it doesn't require inventing new >> uapi to do it. >> > [wangtao] Thank you for the discussion. I fully support any method that enables > dmabuf direct I/O. > > I understand using sendfile/splice with regular files for dmabuf > adds an extra CPU copy, preventing zero-copy. For example: > sendfile path: [DISK] → DMA → [page cache] → CPU copy → [memory file]. Yeah, but why can't you work on improving that? > The read() syscall can't pass regular file fd parameters, so I added > an ioctl command. > While copy_file_range() supports two fds (fd_in/fd_out), it blocks cross-fs use. > Even without this restriction, file_out->f_op->copy_file_range > only enables dmabuf direct reads from regular files, not writes. > > Since dmabuf's direct I/O limitation comes from its unique > attachment/map/fence model and lacks suitable syscalls, adding > an ioctl seems necessary. I absolutely don't see that. Both splice and sendfile can take two regular file descriptors. That the underlying fops currently can't do that is not a valid argument for adding new uAPI. It just means that you need to work on improving those fops. As long as nobody proves to me that the existing uAPI isn't sufficient for this use case I will systematically reject any approach to adding new one. Regards, Christian. > When system exporters return a duplicated sg_table via map_dma_buf > (used exclusively like a pages array), they should retain control > over it. > > I welcome all solutions to achieve dmabuf direct I/O! Your feedback > is greatly appreciated. > >> 1G from ext4 on 6.12.20 | read/sendfile (ms) w/ 3 > drop_caches >> ------------------------|------------------- >> udmabuf buffer read | 1210 >> udmabuf direct read | 671 >> udmabuf buffer sendfile | 1096 >> udmabuf direct sendfile | 2340 >> >> >> >>> >>>>> >>>>>>> dmabuf buffer read | 51 | 1068 | 1118 >>>>>>> dmabuf direct read | 52 | 297 | 349 >>>>>>> >>>>>>> udmabuf sendfile test steps: >>>>>>> 1. Open data file(1024MB), get back_fd 2. Create memfd(32MB) # >>>>>>> Loop steps 2-6 3. Allocate udmabuf with memfd 4. Call >>>>>>> sendfile(memfd, >>>>>>> back_fd) 5. Close memfd after sendfile 6. Close udmabuf 7. >>>>>>> Close back_fd >>>>>>> >>>>>>>> >>>>>>>> Regards, >>>>>>>> Christian. >>>>>>> >>>>>> >>>

2 days, 15 hours

Re: [PATCH v5 01/10] dt-bindings: npu: rockchip,rknn: Add bindings

by Krzysztof Kozlowski

On Tue, May 20, 2025 at 12:26:54PM GMT, Tomeu Vizoso wrote: > Add the bindings for the Neural Processing Unit IP from Rockchip. > > v2: > - Adapt to new node structure (one node per core, each with its own > IOMMU) > - Several misc. fixes from Sebastian Reichel > > v3: > - Split register block in its constituent subblocks, and only require > the ones that the kernel would ever use (Nicolas Frattaroli) > - Group supplies (Rob Herring) > - Explain the way in which the top core is special (Rob Herring) > > v4: > - Change required node name to npu@ (Rob Herring and Krzysztof Kozlowski) > - Remove unneeded items: (Krzysztof Kozlowski) > - Fix use of minItems/maxItems (Krzysztof Kozlowski) > - Add reg-names to list of required properties (Krzysztof Kozlowski) > - Fix example (Krzysztof Kozlowski) > > v5: > - Rename file to rockchip,rk3588-rknn-core.yaml (Krzysztof Kozlowski) > - Streamline compatible property (Krzysztof Kozlowski) > This is a big patchset, so please slow down and do not send it every day but allow people to actually review the version you post. Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> Best regards, Krzysztof

2 days, 15 hours

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