[PATCH 0/7] drm/i915: Move LMEM (VRAM) management over to TTM

Thomas Hellström thomas.hellstrom at linux.intel.com
Tue May 11 13:25:18 UTC 2021


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
- TTM CPU pagefaulting
- Pipelined accelerated moves / migration


Thomas Hellström (7):
  drm/i915: Untangle the vma pages_mutex
  drm/i915: Don't free shared locks while shared
  drm/i915/ttm, drm/ttm: Initialize the ttm device and memory managers.
  drm/i915/ttm: Embed a ttm buffer object in the i915 gem object
  drm/i915/ttm, drm/ttm: Add a generic TTM memcpy move for page-based
    iomem
  drm/i915/ttm, drm/ttm: Introduce a TTM i915 gem object backend
  drm/i915/lmem: Verify checks for lmem residency

 drivers/gpu/drm/i915/Kconfig                  |   1 +
 drivers/gpu/drm/i915/Makefile                 |   4 +-
 drivers/gpu/drm/i915/display/intel_display.c  |   2 +-
 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_object.c    | 161 +++-
 drivers/gpu/drm/i915/gem/i915_gem_object.h    |  13 +
 .../gpu/drm/i915/gem/i915_gem_object_types.h  |  37 +-
 drivers/gpu/drm/i915/gem/i915_gem_pages.c     |   3 +-
 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       | 534 ++++++++++++
 drivers/gpu/drm/i915/gem/i915_gem_ttm.h       |  48 ++
 .../gpu/drm/i915/gem/i915_gem_ttm_bo_util.c   | 155 ++++
 .../gpu/drm/i915/gem/i915_gem_ttm_bo_util.h   | 141 ++++
 drivers/gpu/drm/i915/gt/intel_ggtt.c          |  13 +-
 drivers/gpu/drm/i915/gt/intel_gt.c            |   2 -
 drivers/gpu/drm/i915/gt/intel_gtt.c           |  45 +-
 drivers/gpu/drm/i915/gt/intel_gtt.h           |  29 +-
 drivers/gpu/drm/i915/gt/intel_ppgtt.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               |   7 +-
 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       |  35 +
 drivers/gpu/drm/i915/i915_vma.c               |  33 +-
 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       | 247 ++++++
 drivers/gpu/drm/i915/intel_region_ttm.h       |  32 +
 drivers/gpu/drm/i915/selftests/i915_buddy.c   | 789 ------------------
 .../drm/i915/selftests/i915_mock_selftests.h  |   1 -
 .../drm/i915/selftests/intel_memory_region.c  | 133 +--
 drivers/gpu/drm/i915/selftests/mock_region.c  |  51 +-
 drivers/gpu/drm/ttm/ttm_bo.c                  |  13 +
 drivers/gpu/drm/ttm/ttm_range_manager.c       |  55 +-
 include/drm/ttm/ttm_bo_driver.h               |  23 +
 include/drm/ttm/ttm_device.h                  |   9 +
 46 files changed, 1876 insertions(+), 1879 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
 create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_ttm_bo_util.c
 create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_ttm_bo_util.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

-- 
2.30.2



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