[Intel-gfx] [PATCH v9 7/8] drm/i915/ttm: use cached system pages when evicting lmem

Matthew Auld
2021-10-18T09:12:33Z

This should let us do an accelerated copy directly to the shmem pages
when temporarily moving lmem-only objects, where the i915-gem shrinker
can later kick in to swap out the pages, if needed.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 8de1031a2c6e..d37581d9194c 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -134,11 +134,11 @@ static enum ttm_caching
i915_ttm_select_tt_caching(const struct drm_i915_gem_object *obj)
{
/*
- * Objects only allowed in system get cached cpu-mappings.
- * Other objects get WC mapping for now. Even if in system.
+ * Objects only allowed in system get cached cpu-mappings, or when
+ * evicting lmem-only buffers to system for swapping. Other objects get
+ * WC mapping for now. Even if in system.
*/
- if (obj->mm.region->type == INTEL_MEMORY_SYSTEM &&
- obj->mm.n_placements <= 1)
+ if (obj->mm.n_placements <= 1)
return ttm_cached;

return ttm_write_combined;
--
2.26.3