[Intel-gfx] [PATCH v5 6/7] drm/i915: Don't back up pinned LMEM context images and rings during suspend

Thomas Hellström
2021-09-21T17:52:00Z

Pinned context images are now reset during resume. Don't back them up,
and assuming that rings can be assumed empty at suspend, don't back them
up either.

Introduce a new object flag, I915_BO_ALLOC_PM_VOLATILE meaning that an
object is allowed to lose its content on suspend.

v3:
- Slight documentation clarification (Matthew Auld)

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
---
.../gpu/drm/i915/gem/i915_gem_object_types.h | 17 ++++++++++-------
drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c | 3 +++
drivers/gpu/drm/i915/gt/intel_lrc.c | 3 ++-
drivers/gpu/drm/i915/gt/intel_ring.c | 3 ++-
4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index 734cc8e16481..118691ce81d7 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -288,16 +288,19 @@ struct drm_i915_gem_object {
I915_SELFTEST_DECLARE(struct list_head st_link);

unsigned long flags;
-#define I915_BO_ALLOC_CONTIGUOUS BIT(0)
-#define I915_BO_ALLOC_VOLATILE BIT(1)
-#define I915_BO_ALLOC_CPU_CLEAR BIT(2)
-#define I915_BO_ALLOC_USER BIT(3)
+#define I915_BO_ALLOC_CONTIGUOUS BIT(0)
+#define I915_BO_ALLOC_VOLATILE BIT(1)
+#define I915_BO_ALLOC_CPU_CLEAR BIT(2)
+#define I915_BO_ALLOC_USER BIT(3)
+/* Object is allowed to lose its contents on suspend / resume, even if pinned */
+#define I915_BO_ALLOC_PM_VOLATILE BIT(4)
#define I915_BO_ALLOC_FLAGS (I915_BO_ALLOC_CONTIGUOUS | \
I915_BO_ALLOC_VOLATILE | \
I915_BO_ALLOC_CPU_CLEAR | \
- I915_BO_ALLOC_USER)
-#define I915_BO_READONLY BIT(4)
-#define I915_TILING_QUIRK_BIT 5 /* unknown swizzling; do not release! */
+ I915_BO_ALLOC_USER | \
+ I915_BO_ALLOC_PM_VOLATILE)
+#define I915_BO_READONLY BIT(5)
+#define I915_TILING_QUIRK_BIT 6 /* unknown swizzling; do not release! */

/**
* @mem_flags - Mutable placement-related flags
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
index cb1c46724f70..03a00d193f40 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
@@ -60,6 +60,9 @@ static int i915_ttm_backup(struct i915_gem_apply_to_region *apply,
if (!pm_apply->backup_pinned)
return 0;

+ if (obj->flags & I915_BO_ALLOC_PM_VOLATILE)
+ return 0;
+
backup = i915_gem_object_create_shmem(i915, obj->base.size);
if (IS_ERR(backup))
return PTR_ERR(backup);
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
index 6ba8daea2f56..3ef9eaf8c50e 100644
--- a/drivers/gpu/drm/i915/gt/intel_lrc.c
+++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
@@ -942,7 +942,8 @@ __lrc_alloc_state(struct intel_context *ce, struct intel_engine_cs *engine)
context_size += PAGE_SIZE;
}

- obj = i915_gem_object_create_lmem(engine->i915, context_size, 0);
+ obj = i915_gem_object_create_lmem(engine->i915, context_size,
+ I915_BO_ALLOC_PM_VOLATILE);
if (IS_ERR(obj))
obj = i915_gem_object_create_shmem(engine->i915, context_size);
if (IS_ERR(obj))
diff --git a/drivers/gpu/drm/i915/gt/intel_ring.c b/drivers/gpu/drm/i915/gt/intel_ring.c
index 7c4d5158e03b..2fdd52b62092 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring.c
@@ -112,7 +112,8 @@ static struct i915_vma *create_ring_vma(struct i915_ggtt *ggtt, int size)
struct drm_i915_gem_object *obj;
struct i915_vma *vma;

- obj = i915_gem_object_create_lmem(i915, size, I915_BO_ALLOC_VOLATILE);
+ obj = i915_gem_object_create_lmem(i915, size, I915_BO_ALLOC_VOLATILE |
+ I915_BO_ALLOC_PM_VOLATILE);
if (IS_ERR(obj) && i915_ggtt_has_aperture(ggtt))
obj = i915_gem_object_create_stolen(i915, size);
if (IS_ERR(obj))
--
2.31.1