[PATCH v6 3/3] drm/i915/ttm: Use TTM for system memory
Thomas Hellström
thomas.hellstrom at linux.intel.com
Mon Jun 21 19:36:44 UTC 2021
For discrete, use TTM for both cached and WC system memory. That means
we currently rely on the TTM memory accounting / shrinker. For cached
system memory we should consider remaining shmem-backed, which can be
implemented from our ttm_tt_populate callback. We can then also reuse our
own very elaborate shrinker for that memory.
Signed-off-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld at intel.com>
---
v2:
- Fix IS_ERR_OR_NULL() check to IS_ERR() (Reported by Matthew Auld)
v3:
- Commit message typo fix
v6:
- Fix TODO:s for supporting system memory with TTM.
- Update the object GEM region after a TTM move if compatible.
- Add a couple of warnings for shmem on DGFX.
---
drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 3 ++
drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 51 +++++++++++++++++-----
drivers/gpu/drm/i915/i915_drv.h | 3 --
drivers/gpu/drm/i915/intel_memory_region.c | 7 ++-
drivers/gpu/drm/i915/intel_memory_region.h | 8 ++++
5 files changed, 58 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
index 7aa1c95c7b7d..3648ae1d6628 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
@@ -284,6 +284,7 @@ __i915_gem_object_release_shmem(struct drm_i915_gem_object *obj,
bool needs_clflush)
{
GEM_BUG_ON(obj->mm.madv == __I915_MADV_PURGED);
+ GEM_WARN_ON(IS_DGFX(to_i915(obj->base.dev)));
if (obj->mm.madv == I915_MADV_DONTNEED)
obj->mm.dirty = false;
@@ -302,6 +303,7 @@ void i915_gem_object_put_pages_shmem(struct drm_i915_gem_object *obj, struct sg_
struct pagevec pvec;
struct page *page;
+ GEM_WARN_ON(IS_DGFX(to_i915(obj->base.dev)));
__i915_gem_object_release_shmem(obj, pages, true);
i915_gem_gtt_finish_pages(obj, pages);
@@ -560,6 +562,7 @@ i915_gem_object_create_shmem_from_data(struct drm_i915_private *dev_priv,
resource_size_t offset;
int err;
+ GEM_WARN_ON(IS_DGFX(dev_priv));
obj = i915_gem_object_create_shmem(dev_priv, round_up(size, PAGE_SIZE));
if (IS_ERR(obj))
return obj;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 966b292d07da..07097f150065 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -286,6 +286,25 @@ static void i915_ttm_adjust_gem_after_move(struct drm_i915_gem_object *obj)
{
struct ttm_buffer_object *bo = i915_gem_to_ttm(obj);
unsigned int cache_level;
+ unsigned int i;
+
+ /*
+ * If object was moved to an allowable region, update the object
+ * region to consider it migrated. Note that if it's currently not
+ * in an allowable region, it's evicted and we don't update the
+ * object region.
+ */
+ if (intel_region_to_ttm_type(obj->mm.region) != bo->resource->mem_type) {
+ for (i = 0; i < obj->mm.n_placements; ++i) {
+ struct intel_memory_region *mr = obj->mm.placements[i];
+
+ if (intel_region_to_ttm_type(mr) == bo->resource->mem_type &&
+ mr != obj->mm.region) {
+ intel_memory_region_put(obj->mm.region);
+ obj->mm.region = intel_memory_region_get(mr);
+ }
+ }
+ }
obj->mem_flags &= ~(I915_BO_FLAG_STRUCT_PAGE | I915_BO_FLAG_IOMEM);
@@ -615,13 +634,6 @@ static int i915_ttm_get_pages(struct drm_i915_gem_object *obj)
/* Move to the requested placement. */
i915_ttm_placement_from_obj(obj, &requested, busy, &placement);
- /*
- * For now we support LMEM only with TTM.
- * TODO: Remove with system support
- */
- GEM_BUG_ON(requested.mem_type < I915_PL_LMEM0 ||
- busy[0].mem_type < I915_PL_LMEM0);
-
/* First try only the requested placement. No eviction. */
real_num_busy = fetch_and_zero(&placement.num_busy_placement);
ret = ttm_bo_validate(bo, &placement, &ctx);
@@ -635,9 +647,6 @@ static int i915_ttm_get_pages(struct drm_i915_gem_object *obj)
ret == -EAGAIN)
return ret;
- /* TODO: Remove this when we support system as TTM. */
- real_num_busy = 1;
-
/*
* If the initial attempt fails, allow all accepted placements,
* evicting if necessary.
@@ -872,3 +881,25 @@ int __i915_gem_ttm_object_init(struct intel_memory_region *mem,
return 0;
}
+
+static const struct intel_memory_region_ops ttm_system_region_ops = {
+ .init_object = __i915_gem_ttm_object_init,
+};
+
+struct intel_memory_region *
+i915_gem_ttm_system_setup(struct drm_i915_private *i915,
+ u16 type, u16 instance)
+{
+ struct intel_memory_region *mr;
+
+ mr = intel_memory_region_create(i915, 0,
+ totalram_pages() << PAGE_SHIFT,
+ PAGE_SIZE, 0,
+ type, instance,
+ &ttm_system_region_ops);
+ if (IS_ERR(mr))
+ return mr;
+
+ intel_memory_region_set_name(mr, "system-ttm");
+ return mr;
+}
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 01e11fe38642..bfbfbae57573 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1751,9 +1751,6 @@ void i915_gem_cleanup_userptr(struct drm_i915_private *dev_priv);
void i915_gem_init_early(struct drm_i915_private *dev_priv);
void i915_gem_cleanup_early(struct drm_i915_private *dev_priv);
-struct intel_memory_region *i915_gem_shmem_setup(struct drm_i915_private *i915,
- u16 type, u16 instance);
-
static inline void i915_gem_drain_freed_objects(struct drm_i915_private *i915)
{
/*
diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
index df59f884d37c..779eb2fa90b6 100644
--- a/drivers/gpu/drm/i915/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/intel_memory_region.c
@@ -173,7 +173,12 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
instance = intel_region_map[i].instance;
switch (type) {
case INTEL_MEMORY_SYSTEM:
- mem = i915_gem_shmem_setup(i915, type, instance);
+ if (IS_DGFX(i915))
+ mem = i915_gem_ttm_system_setup(i915, type,
+ instance);
+ else
+ mem = i915_gem_shmem_setup(i915, type,
+ instance);
break;
case INTEL_MEMORY_STOLEN_LOCAL:
mem = i915_gem_stolen_lmem_setup(i915, type, instance);
diff --git a/drivers/gpu/drm/i915/intel_memory_region.h b/drivers/gpu/drm/i915/intel_memory_region.h
index 2be8433d373a..b1b9e461d53b 100644
--- a/drivers/gpu/drm/i915/intel_memory_region.h
+++ b/drivers/gpu/drm/i915/intel_memory_region.h
@@ -125,4 +125,12 @@ intel_memory_region_set_name(struct intel_memory_region *mem,
int intel_memory_region_reserve(struct intel_memory_region *mem,
resource_size_t offset,
resource_size_t size);
+
+struct intel_memory_region *
+i915_gem_ttm_system_setup(struct drm_i915_private *i915,
+ u16 type, u16 instance);
+struct intel_memory_region *
+i915_gem_shmem_setup(struct drm_i915_private *i915,
+ u16 type, u16 instance);
+
#endif
--
2.31.1
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