DMEM cgroup pull request

This introduces a new cgroup controller to limit the device memory.
Notable users would be DRM, dma-buf heaps, or v4l2.

This pull request is based on the series developped by Maarten
Lankhorst, Friedrich Vock, and I:
https://lore.kernel.org/all/20241204134410.1161769-1-dev@lankhorst.se/

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maxime Ripard <mripard@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250110-cryptic-warm-mandrill-b71f5d@houat

cgroup resource allocation has to be handled in TTM, so -EAGAIN from
cgroups can be converted into -ENOSPC, and the limitcg can be properly
evicted in ttm code.

When hitting a resource limit through -EAGAIN, the cgroup for which the
limit is hit is also returned. This allows eviction to delete only from
cgroups which are a subgroup of the current cgroup.

The returned CSS is used to determine if eviction is valuable for a
given resource, and allows TTM to only target specific resources to
lower memory usage.

Co-developed-by: Friedrich Vock <friedrich.vock@gmx.de>
Signed-off-by: Friedrich Vock <friedrich.vock@gmx.de>
Co-developed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20241204134410.1161769-4-dev@lankhorst.se
Signed-off-by: Maxime Ripard <mripard@kernel.org>

Non-contiguous VRAM cannot easily be mapped in TTM nor can non-visible
VRAM easily be accessed. Add ttm_bo_access, which is similar to
ttm_bo_vm_access, to access such memory.

v4:
 - Fix checkpatch warnings (CI)
v5:
 - Fix checkpatch warnings (CI)
v6:
 - Fix kernel doc (Auld)
v7:
 - Move ttm_bo_access to ttm_bo_vm.c (Christian)

Cc: Christian König <christian.koenig@amd.com>
Reported-by: Christoph Manszewski <christoph.manszewski@intel.com>
Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Tested-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241126174615.2665852-3-matthew.brost@intel.com

Add a missing colon.

Cc: dri-devel@lists.freedesktop.org
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/linux-next/20241010160942.192caf60@canb.auug.org.au/
Fixes: fc5d96670eb2 ("drm/ttm: Move swapped objects off the manager's LRU list")
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241010124545.82023-1-thomas.hellstrom@linux.intel.com

Resources of swapped objects remains on the TTM_PL_SYSTEM manager's
LRU list, which is bad for the LRU walk efficiency.

Rename the device-wide "pinned" list to "unevictable" and move
also resources of swapped-out objects to that list.

An alternative would be to create an "UNEVICTABLE" priority to
be able to keep the pinned- and swapped objects on their
respective manager's LRU without affecting the LRU walk efficiency.

v2:
- Remove a bogus WARN_ON (Christian König)
- Update ttm_resource_[add|del] bulk move (Christian König)
- Fix TTM KUNIT tests (Intel CI)
v3:
- Check for non-NULL bo->resource in ttm_bo_populate().
v4:
- Don't move to LRU tail during swapout until the resource
  is properly swapped or there was a swapout failure.
  (Intel Ci)
- Add a newline after checkpatch check.
v5:
- Introduce ttm_resource_is_swapped() to avoid a corner-case where
  a newly created resource was considered swapped. (Intel CI)
v6:
- Move an assert.

Cc: Christian König <christian.koenig@amd.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: <dri-devel@lists.freedesktop.org>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240911121859.85387-2-thomas.hellstrom@linux.intel.com

Thomas needs 5a498d4d06d6 ("drm/fbdev-dma: Only install deferred I/O
if necessary") in drm-misc, so start the backmerge cascade.

Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>

s/tryock_only/trylock_only/

Fixes: da966b82bf3d ("drm/ttm: Provide a generic LRU walker helper")
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240823141110.3431423-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

This reverts commit 0ddd2ae586d28e521d37393364d989ce118802e0.

This patch causes sluggishness and stuttering in graphical
apps.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3564
Link: https://www.spinics.net/lists/dri-devel/msg457005.html
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Zhu Lingshan <lingshan.zhu@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240820134600.1909370-1-alexander.deucher@amd.com

Use the LRU walker for eviction. This helps
removing a lot of code with weird locking
semantics.

The functionality is slightly changed so that
when trylocked buffer objects are exhausted, we
continue to interleave walks with ticket-locks while
there is still progress made. The list walks are
not restarted in-between evictions.

Also provide a separate ttm_bo_evict_first()
function for its single user. The context of that
user allows sleeping dma_resv locks.

v6:
- Various cleanups suggested by Matthew Brost.
- Fix error return code of ttm_bo_evict_first(). (Matthew Brost)
- Fix an error check that was inverted. (Matthew Brost)
v7:
- Use s64 rather than long (Christian König)
- Early ttm_resource_cursor_fini() in ttm_bo_evict_first().
- Simplify check for bo_moved in ttm_bo_evict_first().
  (Christian König)
- Don't evict pinned bos.

Cc: Christian König <christian.koenig@amd.com>
Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: <dri-devel@lists.freedesktop.org>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com> #v6
Link: https://patchwork.freedesktop.org/patch/msgid/20240705153206.68526-8-thomas.hellstrom@linux.intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>

Rework the TTM swapping to use the LRU walker helper.
This helps fixing up the ttm_bo_swapout() interface
to be consistent about not requiring any locking.

For now mimic the current behaviour of using trylock
only. We could be using ticket-locks here but defer
that until it's deemed necessary. The TTM swapout
functionality is a bit weird anyway since it
alternates between memory types without exhausting
TTM_PL_SYSTEM first.

Intentionally keep pages as the unit of progress since
changing that to bytes is an unrelated change that can
be done later.

v6:
- Improve on error code translation in the swapout callback
  (Matthew Brost).
v7:
- Use s64 rather than long.
- Remove ttm_resource_cursor_fini() since it's no longer used.
- Rename ttm_resource_cursor_fini_locked() to
  ttm_resource_cursor_fini().
- Don't swap out pinned bos.

Cc: Christian König <christian.koenig@amd.com>
Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: <dri-devel@lists.freedesktop.org>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com> #v6
Link: https://patchwork.freedesktop.org/patch/msgid/20240705153206.68526-7-thomas.hellstrom@linux.intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>