[v10,00/11] Move LMEM (VRAM) management over to TTM

Message

Thomas Hellstrom June 2, 2021, 8:38 a.m. UTC

This is an initial patch series to move discrete memory management over to
TTM. It will be followed up shortly with adding more functionality.

The buddy allocator is temporarily removed along with its selftests and
It is replaced with the TTM range manager and some selftests are adjusted
to account for introduced fragmentation. Work is ongoing to reintroduce the
buddy allocator as a TTM resource manager.

A new memcpy ttm move is introduced that uses kmap_local() functionality
rather than vmap(). Among other things stated in the patch commit message
it helps us deal with page-pased LMEM memory. It is generic enough to replace
the ttm memcpy move with some additional work if so desired. On x86 it also
enables prefetching reads from write-combined memory.

Finally the old i915 gem object LMEM backend is replaced with a
i915 gem object TTM backend and some additional i915 gem object ops are
introduced to support the added functionality.
Currently it is used only to support management and eviction of the LMEM
region, but work is underway to extend the support to system memory. In this
way we use TTM the way it was originally intended, having the GPU binding
taken care of by driver code.

Intention is to follow up with
- System memory support
- Pipelined accelerated moves / migration
- Re-added buddy allocator in the TTM framework

v2:
- Add patches to move pagefaulting over to TTM
- Break out TTM changes to separate patches
- Address various review comments as detailed in the affected patches

v3:
- Drop TTM pagefaulting patches for now due changing approach due to a NAK.
- Address feedback on TTM patches
- Move the new TTM memcpy functionality into TTM.
- Move fast WC memcpy to drm
- Various fixes all over the place as shown in patch commit messages.

v4:
- Re-add TTM pagefaulting patches.
- Addressed review feedback mainly from Matthew Auld
- Fixed the mock ttm device code that was using an incorrect approach.

v5:
- Cleanups in the TTM pagefaulting patches.
- Just add the WC memcpy to DRM without removing from i915
  (Suggested by Daniel Vetter).
- Various minor fixes as reported in patch log messages.
v6:
- Fix a merge conflict causing build error.
v7:
- Fix the WC memcpy compilation and perform a fallback memcpy in addition to
  warning in interrupt (Suggested by Christian König)
- Renistate check for ttm_tt_is_populated() on swapout.
v8:
- Added a couple of acks and r-bs
- pgoff_t -> u32 in interface of ttm_move_memcpy.
- Fix missing export in !X86 WC memcpy.
v9:
- Fix a NULL pointer deref if bo->ttm == NULL
v10:
- Fix a kerneldoc title underline

Cc: Christian König <[e-mail]>

Maarten Lankhorst (2):
  drm/vma: Add a driver_private member to vma_node.
  drm/i915: Use ttm mmap handling for ttm bo's.

Thomas Hellström (9):
  drm/i915/ttm Initialize the ttm device and memory managers
  drm/i915/ttm: Embed a ttm buffer object in the i915 gem object
  drm/ttm: Add a generic TTM memcpy move for page-based iomem
  drm: Add a prefetching memcpy_from_wc
  drm/ttm: Use drm_memcpy_from_wc for TTM bo moves
  drm/ttm: Document and optimize ttm_bo_pipeline_gutting()
  drm/ttm, drm/amdgpu: Allow the driver some control over swapping
  drm/i915/ttm: Introduce a TTM i915 gem object backend
  drm/i915/lmem: Verify checks for lmem residency

 Documentation/gpu/drm-mm.rst                  |   4 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c       |   4 +
 drivers/gpu/drm/drm_cache.c                   | 148 ++++
 drivers/gpu/drm/drm_drv.c                     |   2 +
 drivers/gpu/drm/drm_gem.c                     |   9 -
 drivers/gpu/drm/i915/Kconfig                  |   1 +
 drivers/gpu/drm/i915/Makefile                 |   3 +-
 drivers/gpu/drm/i915/display/intel_display.c  |   2 +-
 drivers/gpu/drm/i915/gem/i915_gem_create.c    |   9 +-
 drivers/gpu/drm/i915/gem/i915_gem_lmem.c      |  71 +-
 drivers/gpu/drm/i915/gem/i915_gem_lmem.h      |   5 -
 drivers/gpu/drm/i915/gem/i915_gem_mman.c      |  83 +-
 drivers/gpu/drm/i915/gem/i915_gem_object.c    | 150 +++-
 drivers/gpu/drm/i915/gem/i915_gem_object.h    |  19 +-
 .../gpu/drm/i915/gem/i915_gem_object_types.h  |  48 +-
 drivers/gpu/drm/i915/gem/i915_gem_pages.c     |   6 +-
 drivers/gpu/drm/i915/gem/i915_gem_region.c    | 126 +--
 drivers/gpu/drm/i915/gem/i915_gem_region.h    |   4 -
 drivers/gpu/drm/i915/gem/i915_gem_shmem.c     |   4 +-
 drivers/gpu/drm/i915/gem/i915_gem_stolen.c    |  10 +-
 drivers/gpu/drm/i915/gem/i915_gem_stolen.h    |   9 +-
 drivers/gpu/drm/i915/gem/i915_gem_ttm.c       | 647 ++++++++++++++
 drivers/gpu/drm/i915/gem/i915_gem_ttm.h       |  48 ++
 .../drm/i915/gem/selftests/i915_gem_mman.c    |  90 +-
 drivers/gpu/drm/i915/gt/intel_gt.c            |   2 -
 drivers/gpu/drm/i915/gt/intel_region_lmem.c   |  30 +-
 drivers/gpu/drm/i915/i915_buddy.c             | 435 ----------
 drivers/gpu/drm/i915/i915_buddy.h             | 131 ---
 drivers/gpu/drm/i915/i915_drv.c               |   8 +
 drivers/gpu/drm/i915/i915_drv.h               |   8 +-
 drivers/gpu/drm/i915/i915_gem.c               |   6 +-
 drivers/gpu/drm/i915/i915_globals.c           |   1 -
 drivers/gpu/drm/i915/i915_globals.h           |   1 -
 drivers/gpu/drm/i915/i915_scatterlist.c       |  70 ++
 drivers/gpu/drm/i915/i915_scatterlist.h       |   4 +
 drivers/gpu/drm/i915/intel_memory_region.c    | 181 ++--
 drivers/gpu/drm/i915/intel_memory_region.h    |  45 +-
 drivers/gpu/drm/i915/intel_region_ttm.c       | 220 +++++
 drivers/gpu/drm/i915/intel_region_ttm.h       |  37 +
 drivers/gpu/drm/i915/selftests/i915_buddy.c   | 789 ------------------
 .../drm/i915/selftests/i915_mock_selftests.h  |   1 -
 drivers/gpu/drm/i915/selftests/igt_mmap.c     |  25 +-
 drivers/gpu/drm/i915/selftests/igt_mmap.h     |  12 +-
 .../drm/i915/selftests/intel_memory_region.c  | 133 +--
 .../gpu/drm/i915/selftests/mock_gem_device.c  |  10 +
 drivers/gpu/drm/i915/selftests/mock_region.c  |  70 +-
 drivers/gpu/drm/ttm/ttm_bo.c                  |  66 +-
 drivers/gpu/drm/ttm/ttm_bo_util.c             | 320 +++----
 drivers/gpu/drm/ttm/ttm_module.c              |  35 +
 drivers/gpu/drm/ttm/ttm_resource.c            | 193 +++++
 drivers/gpu/drm/ttm/ttm_tt.c                  |  45 +
 include/drm/drm_cache.h                       |   7 +
 include/drm/drm_vma_manager.h                 |   2 +-
 include/drm/ttm/ttm_bo_driver.h               |  28 +
 include/drm/ttm/ttm_caching.h                 |   2 +
 include/drm/ttm/ttm_kmap_iter.h               |  61 ++
 include/drm/ttm/ttm_resource.h                |  61 ++
 include/drm/ttm/ttm_tt.h                      |  29 +
 58 files changed, 2416 insertions(+), 2154 deletions(-)
 create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_ttm.c
 create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_ttm.h
 delete mode 100644 drivers/gpu/drm/i915/i915_buddy.c
 delete mode 100644 drivers/gpu/drm/i915/i915_buddy.h
 create mode 100644 drivers/gpu/drm/i915/intel_region_ttm.c
 create mode 100644 drivers/gpu/drm/i915/intel_region_ttm.h
 delete mode 100644 drivers/gpu/drm/i915/selftests/i915_buddy.c
 create mode 100644 include/drm/ttm/ttm_kmap_iter.h