Do you have a pointer to a git branch with this series and all dependencies to ease testing? On Thu, Aug 12, 2021 at 01:30:47AM -0500, Alex Sierra wrote: > v1: > AMD is building a system architecture for the Frontier supercomputer with a > coherent interconnect between CPUs and GPUs. This hardware architecture allows > the CPUs to coherently access GPU device memory. We have hardware in our labs > and we are working with our partner HPE on the BIOS, firmware and software > for delivery to the DOE. > > The system BIOS advertises the GPU device memory (aka VRAM) as SPM > (special purpose memory) in the UEFI system address map. The amdgpu driver looks > it up with lookup_resource and registers it with devmap as MEMORY_DEVICE_GENERIC > using devm_memremap_pages. > > Now we're trying to migrate data to and from that memory using the migrate_vma_* > helpers so we can support page-based migration in our unified memory allocations, > while also supporting CPU access to those pages. > > This patch series makes a few changes to make MEMORY_DEVICE_GENERIC pages behave > correctly in the migrate_vma_* helpers. We are looking for feedback about this > approach. If we're close, what's needed to make our patches acceptable upstream? > If we're not close, any suggestions how else to achieve what we are trying to do > (i.e. page migration and coherent CPU access to VRAM)? > > This work is based on HMM and our SVM memory manager that was recently upstreamed > to Dave Airlie's drm-next branch > https://cgit.freedesktop.org/drm/drm/log/?h=drm-next > On top of that we did some rework of our VRAM management for migrations to remove > some incorrect assumptions, allow partially successful migrations and GPU memory > mappings that mix pages in VRAM and system memory. > https://lore.kernel.org/dri-devel/20210527205606.2660-6-Felix.Kuehling@xxxxxxx/T/#r996356015e295780eb50453e7dbd5d0d68b47cbc > > v2: > This patch series version has merged "[RFC PATCH v3 0/2] > mm: remove extra ZONE_DEVICE struct page refcount" patch series made by > Ralph Campbell. It also applies at the top of these series, our changes > to support device generic type in migration_vma helpers. > This has been tested in systems with device memory that has coherent > access by CPU. > > Also addresses the following feedback made in v1: > - Isolate in one patch kernel/resource.c modification, based > on Christoph's feedback. > - Add helpers check for generic and private type to avoid > duplicated long lines. > > v3: > - Include cover letter from v1. > - Rename dax_layout_is_idle_page func to dax_page_unused in patch > ext4/xfs: add page refcount helper. > > v4: > - Add support for zone device generic type in lib/test_hmm and > tool/testing/selftest/vm/hmm-tests. > - Add missing page refcount helper to fuse/dax.c. This was included in > one of Ralph Campbell's patches. > > v5: > - Cosmetic changes on patches 3, 5 and 13 > - Bug founded at test_hmm, remove devmem->pagemap.type = MEMORY_DEVICE_PRIVATE > at dmirror_allocate_chunk that was forcing to configure pagemap.type to > MEMORY_DEVICE_PRIVATE. > - A bug was found while running one of the xfstest (generic/413) used to > validate fs_dax device type. This was first introduced by patch: "mm: remove > extra ZONE_DEVICE struct page refcount" whic is part of these patch series. > The bug was showed as WARNING message at try_grab_page function call, due to > a page refcounter equal to zero. Part of "mm: remove extra ZONE_DEVICE struct > page refcount" changes, was to initialize page refcounter to zero. Therefore, > a special condition was added to try_grab_page on this v5, were it checks for > device zone pages too. It is included in the same patch. > > This is how mm changes from these patch series have been validated: > - hmm-tests were run using device private and device generic types. This last, > just added in these patch series. efi_fake_mem was used to mimic SPM memory > for device generic. > - xfstests tool was used to validate fs-dax device type and page refcounter > changes. DAX configuration was used along with emulated Persisten Memory set as > memmap=4G!4G memmap=4G!9G. xfstests were run from ext4 and generic lists. Some > of them, did not run due to limitations in configuration. Ex. test not > supporting specific file system or DAX mode. > Only three tests failed, generic/356/357 and ext4/049. However, these failures > were consistent before and after applying these patch series. > xfstest configuration: > TEST_DEV=/dev/pmem0 > TEST_DIR=/mnt/ram0 > SCRATCH_DEV=/dev/pmem1 > SCRATCH_MNT=/mnt/ram1 > TEST_FS_MOUNT_OPTS="-o dax" > EXT_MOUNT_OPTIONS="-o dax" > MKFS_OPTIONS="-b4096" > xfstest passed list: > Ext4: > 001,003,005,021,022,023,025,026,030,031,032,036,037,038,042,043,044,271,306 > Generic: > 1,2,3,4,5,6,7,8,9,11,12,13,14,15,16,20,21,22,23,24,25,28,29,30,31,32,33,35,37, > 50,52,53,58,60,61,62,63,64,67,69,70,71,75,76,78,79,80,82,84,86,87,88,91,92,94, > 96,97,98,99,103,105,112,113,114,117,120,124,126,129,130,131,135,141,169,184, > 198,207,210,211,212,213,214,215,221,223,225,228,236,237,240,244,245,246,247, > 248,249,255,257,258,263,277,286,294,306,307,308,309,313,315,316,318,319,337, > 346,360,361,371,375,377,379,380,383,384,385,386,389,391,392,393,394,400,401, > 403,404,406,409,410,411,412,413,417,420,422,423,424,425,426,427,428 > > Patches 1-2 Rebased Ralph Campbell's ZONE_DEVICE page refcounting patches. > > Patches 4-5 are for context to show how we are looking up the SPM > memory and registering it with devmap. > > Patches 3,6-8 are the changes we are trying to upstream or rework to > make them acceptable upstream. > > Patches 9-13 add ZONE_DEVICE Generic type support into the hmm test. > > Alex Sierra (11): > kernel: resource: lookup_resource as exported symbol > drm/amdkfd: add SPM support for SVM > drm/amdkfd: generic type as sys mem on migration to ram > include/linux/mm.h: helpers to check zone device generic type > mm: add generic type support to migrate_vma helpers > mm: call pgmap->ops->page_free for DEVICE_GENERIC pages > lib: test_hmm add ioctl to get zone device type > lib: test_hmm add module param for zone device type > lib: add support for device generic type in test_hmm > tools: update hmm-test to support device generic type > tools: update test_hmm script to support SP config > > Ralph Campbell (2): > ext4/xfs: add page refcount helper > mm: remove extra ZONE_DEVICE struct page refcount > > arch/powerpc/kvm/book3s_hv_uvmem.c | 2 +- > drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 22 ++- > drivers/gpu/drm/nouveau/nouveau_dmem.c | 2 +- > fs/dax.c | 8 +- > fs/ext4/inode.c | 5 +- > fs/fuse/dax.c | 4 +- > fs/xfs/xfs_file.c | 4 +- > include/linux/dax.h | 10 + > include/linux/memremap.h | 7 +- > include/linux/mm.h | 54 +----- > kernel/resource.c | 1 + > lib/test_hmm.c | 231 +++++++++++++++-------- > lib/test_hmm_uapi.h | 16 ++ > mm/internal.h | 8 + > mm/memremap.c | 69 ++----- > mm/migrate.c | 25 +-- > mm/page_alloc.c | 3 + > mm/swap.c | 45 +---- > tools/testing/selftests/vm/hmm-tests.c | 142 ++++++++++++-- > tools/testing/selftests/vm/test_hmm.sh | 20 +- > 20 files changed, 405 insertions(+), 273 deletions(-) > > -- > 2.32.0 ---end quoted text---
