Commit Graph

3 Commits

Author SHA1 Message Date
Jason Gunthorpe
7a60c2dd0f drm: Remove SCATTERLIST_MAX_SEGMENT
Since commit 9a40401cfa ("lib/scatterlist: Do not limit max_segment to
PAGE_ALIGNED values") the max_segment input to sg_alloc_table_from_pages()
does not have to be any special value. The new algorithm will always
create something less than what the user provides. Thus eliminate this
confusing constant.

- vmwgfx should use the HW capability, not mix in the OS page size for
  calling dma_set_max_seg_size()

- i915 uses i915_sg_segment_size() both for sg_alloc_table_from_pages
  and for some open coded sgl construction. This doesn't change the value
  since rounddown(size, UINT_MAX) == SCATTERLIST_MAX_SEGMENT

- drm_prime_pages_to_sg uses it as a default if max_segment is zero,
  UINT_MAX is fine to use directly.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Qian Cai <cai@lca.pw>
Cc: "Ursulin, Tvrtko" <tvrtko.ursulin@intel.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/0-v1-44733fccd781+13d-rm_scatterlist_max_jgg@nvidia.com
2020-11-02 14:42:57 +01:00
Matthew Auld
31444afb46 drm/i915: s/for_each_sgt_dma/for_each_sgt_daddr/
The sg_table for our backing store might contain addresses from
stolen-memory or in the future local-memory, at which point this is no
longer a dma-iterator. As a consequence we should now break on NULL
iter.sgp, instead of dmap == 0 which is considered an invalid dma
address.

As a bonus, gcc much prefers this construct,

  Function                                     old     new   delta
  gen8_ggtt_insert_entries                     211     192     -19
  gen6_ggtt_insert_entries                     292     262     -30
  i915_error_object_create                     996     954     -42

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190829201919.21493-1-matthew.auld@intel.com
2019-08-29 21:59:16 +01:00
Chris Wilson
37d63f8fdb drm/i915: Pull scatterlist utils out of i915_gem.h
Out scatterlist utility routines can be pulled out of i915_gem.h for a
bit more decluttering.

v2: Push I915_GTT_PAGE_SIZE out of i915_scatterlist itself and into the
caller.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528092956.14910-9-chris@chris-wilson.co.uk
2019-05-28 12:45:29 +01:00