On 14/09/2021 20:31, Thomas Hellström wrote:
Just evict unpinned objects to system. For pinned LMEM objects,
make a backup system object and blit the contents to that.
Backup is performed in three steps,
1: Opportunistically evict evictable objects using the gpu blitter.
2: After gt idle, evict evictable objects using the gpu blitter. This will
be modified in an upcoming patch to backup pinned objects that are not used
by the blitter itself.
3: Backup remaining pinned objects using memcpy.
Also move uC suspend to after 2) to make sure we have a functional GuC
during 2) if using GuC submission.
v2:
- Major refactor to make sure gem_exec_suspend@hang-SX subtests work, and
suspend / resume works with a slightly modified GuC submission enabling
patch series.
v3:
- Fix a potential use-after-free (Matthew Auld)
- Use i915_gem_object_create_shmem() instead of
i915_gem_object_create_region (Matthew Auld)
- Minor simplifications (Matthew Auld)
- Fix up kerneldoc for i195_ttm_restore_region().
- Final lmem_suspend() call moved to i915_gem_backup_suspend from
i915_gem_suspend_late, since the latter gets called at driver unload
and we don't unnecessarily want to run it at that time.
Signed-off-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/Makefile | 1 +
.../gpu/drm/i915/gem/i915_gem_object_types.h | 1 +
drivers/gpu/drm/i915/gem/i915_gem_pm.c | 92 +++++++-
drivers/gpu/drm/i915/gem/i915_gem_pm.h | 3 +-
drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 29 ++-
drivers/gpu/drm/i915/gem/i915_gem_ttm.h | 10 +
drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c | 203 ++++++++++++++++++
drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.h | 24 +++
drivers/gpu/drm/i915/gt/intel_gt_pm.c | 4 +-
drivers/gpu/drm/i915/i915_drv.c | 10 +-
drivers/gpu/drm/i915/i915_drv.h | 2 +-
11 files changed, 362 insertions(+), 17 deletions(-)
create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
create mode 100644 drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.h
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 9d371be7dc5c..f9b69492a56c 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -154,6 +154,7 @@ gem-y += \
gem/i915_gem_throttle.o \
gem/i915_gem_tiling.o \
gem/i915_gem_ttm.o \
+ gem/i915_gem_ttm_pm.o \
gem/i915_gem_userptr.o \
gem/i915_gem_wait.o \
gem/i915_gemfs.o
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 2471f36aaff3..734cc8e16481 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -534,6 +534,7 @@ struct drm_i915_gem_object {
struct {
struct sg_table *cached_io_st;
struct i915_gem_object_page_iter get_io_page;
+ struct drm_i915_gem_object *backup;
bool created:1;
} ttm;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
index 8b9d7d14c4bd..8736ae1dfbb2 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
@@ -5,6 +5,7 @@
*/
#include "gem/i915_gem_pm.h"
+#include "gem/i915_gem_ttm_pm.h"
#include "gt/intel_gt.h"
#include "gt/intel_gt_pm.h"
#include "gt/intel_gt_requests.h"
@@ -39,7 +40,86 @@ void i915_gem_suspend(struct drm_i915_private *i915)
i915_gem_drain_freed_objects(i915);
}
-void i915_gem_suspend_late(struct drm_i915_private *i915)
+static int lmem_restore(struct drm_i915_private *i915, bool allow_gpu)
+{
+ struct intel_memory_region *mr;
+ int ret = 0, id;
+
+ for_each_memory_region(mr, i915, id) {
+ if (mr->type == INTEL_MEMORY_LOCAL) {
+ ret = i915_ttm_restore_region(mr, allow_gpu);
+ if (ret)
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int lmem_suspend(struct drm_i915_private *i915, bool allow_gpu,
+ bool backup_pinned)
+{
+ struct intel_memory_region *mr;
+ int ret = 0, id;
+
+ for_each_memory_region(mr, i915, id) {
+ if (mr->type == INTEL_MEMORY_LOCAL) {
+ ret = i915_ttm_backup_region(mr, allow_gpu, backup_pinned);
+ if (ret)
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static void lmem_recover(struct drm_i915_private *i915)
+{
+ struct intel_memory_region *mr;
+ int id;
+
+ for_each_memory_region(mr, i915, id)
+ if (mr->type == INTEL_MEMORY_LOCAL)
+ i915_ttm_recover_region(mr);
+}
+
+int i915_gem_backup_suspend(struct drm_i915_private *i915)
+{
+ int ret;
+
+ /* Opportunistically try to evict unpinned objects */
+ ret = lmem_suspend(i915, true, false);
+ if (ret)
+ goto out_recover;
+
+ i915_gem_suspend(i915);
+
+ /*
+ * More objects may have become unpinned as requests were
+ * retired. Now try to evict again. The gt may be wedged here
+ * in which case we automatically fall back to memcpy.
+ */
+ ret = lmem_suspend(i915, true, false);
+ if (ret)
+ goto out_recover;
+
+ /*
+ * Remaining objects are backed up using memcpy once we've stopped
+ * using the migrate context.
+ */
+ ret = lmem_suspend(i915, false, true);
+ if (ret)
+ goto out_recover;
+
+ return 0;
+
+out_recover:
+ lmem_recover(i915);
+
+ return ret;
+}
+
+int i915_gem_suspend_late(struct drm_i915_private *i915)
{
struct drm_i915_gem_object *obj;
struct list_head *phases[] = {
@@ -83,6 +163,8 @@ void i915_gem_suspend_late(struct drm_i915_private *i915)
spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
if (flush)
wbinvd_on_all_cpus();
+
+ return 0;
We can drop this change now?
I guess only slight concern is all the GEM_WARN_ON() instead of proper
error handling in some places, but hopefully these should never be hit
in practice,
Reviewed-by: Matthew Auld <matthew.auld@xxxxxxxxx>