| Message ID | 20170531185210.29189-6-matthew.auld@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 31, 2017 at 07:52:00PM +0100, Matthew Auld wrote: > When inserting into a 48bit PPGTT we should the align the vma start > address to the required page size boundary, to guarantee we use said > page size in the gtt. If we are dealing with multiple page-sizes, we > can't guarantee anything and just align to the largest. For soft pinning > we don't force any alignment. > > Signed-off-by: Matthew Auld <matthew.auld@intel.com> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Cc: Chris Wilson <chris@chris-wilson.co.uk> > --- > drivers/gpu/drm/i915/i915_vma.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c > index 1aba47024656..c355ccb01872 100644 > --- a/drivers/gpu/drm/i915/i915_vma.c > +++ b/drivers/gpu/drm/i915/i915_vma.c > @@ -485,6 +485,18 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags) > if (ret) > goto err_unpin; > } else { > + if (i915_vm_is_48bit(vma->vm) && I would use end > 4G here. As that encapsulates the i915_vm_is_48bit() test and avoids us applying the extra padding to objects that must be tightly packed into the low 32bits. > + obj->mm.page_sizes.sg > I915_GTT_PAGE_SIZE) { > + unsigned int page_alignment = obj->mm.page_sizes.sg; > + > + /* Align to the largest and hope for the best */ > + if (!is_power_of_2(page_alignment)) > + page_alignment = BIT(fls64(page_alignment)-1); fls64() - 1 == ilog2() BIT(ilog2()) == roundup_pow_of_two() linux/log2.h is your friend. > + > + alignment = max_t(typeof(alignment), alignment, > + page_alignment); Make page_alignment be u64 and be happy. -Chris
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 1aba47024656..c355ccb01872 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -485,6 +485,18 @@ i915_vma_insert(struct i915_vma *vma, u64 size, u64 alignment, u64 flags) if (ret) goto err_unpin; } else { + if (i915_vm_is_48bit(vma->vm) && + obj->mm.page_sizes.sg > I915_GTT_PAGE_SIZE) { + unsigned int page_alignment = obj->mm.page_sizes.sg; + + /* Align to the largest and hope for the best */ + if (!is_power_of_2(page_alignment)) + page_alignment = BIT(fls64(page_alignment)-1); + + alignment = max_t(typeof(alignment), alignment, + page_alignment); + } + ret = i915_gem_gtt_insert(vma->vm, &vma->node, size, alignment, obj->cache_level, start, end, flags);
When inserting into a 48bit PPGTT we should the align the vma start address to the required page size boundary, to guarantee we use said page size in the gtt. If we are dealing with multiple page-sizes, we can't guarantee anything and just align to the largest. For soft pinning we don't force any alignment. Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> --- drivers/gpu/drm/i915/i915_vma.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)