path: root/common/recipes-kernel/linux/linux-yocto-4.19.8/0187-drm-amdgpu-use-bulk-moves-for-efficient-VM-LRU-handl.patch

From 09a25a2290321c636b800bf671328c7fe57e110b Mon Sep 17 00:00:00 2001
From: Huang Rui <ray.huang@amd.com>
Date: Mon, 6 Aug 2018 10:57:08 +0800
Subject: [PATCH 0187/2940] drm/amdgpu: use bulk moves for efficient VM LRU
 handling (v6)
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I continue to work for bulk moving that based on the proposal by Christian.

Background:
amdgpu driver will move all PD/PT and PerVM BOs into idle list. Then move all of
them on the end of LRU list one by one. Thus, that cause so many BOs moved to
the end of the LRU, and impact performance seriously.

Then Christian provided a workaround to not move PD/PT BOs on LRU with below
patch:
Commit 0bbf32026cf5ba41e9922b30e26e1bed1ecd38ae ("drm/amdgpu: band aid
validating VM PTs")

However, the final solution should bulk move all PD/PT and PerVM BOs on the LRU
instead of one by one.

Whenever amdgpu_vm_validate_pt_bos() is called and we have BOs which need to be
validated we move all BOs together to the end of the LRU without dropping the
lock for the LRU.

While doing so we note the beginning and end of this block in the LRU list.

Now when amdgpu_vm_validate_pt_bos() is called and we don't have anything to do,
we don't move every BO one by one, but instead cut the LRU list into pieces so
that we bulk move everything to the end in just one operation.

Test data:
+--------------+-----------------+-----------+---------------------------------------+
|              |The Talos        |Clpeak(OCL)|BusSpeedReadback(OCL)                  |
|              |Principle(Vulkan)|           |                                       |
+------------------------------------------------------------------------------------+
|              |                 |           |0.319 ms(1k) 0.314 ms(2K) 0.308 ms(4K) |
| Original     |  147.7 FPS      |  76.86 us |0.307 ms(8K) 0.310 ms(16K)             |
+------------------------------------------------------------------------------------+
| Orignial + WA|                 |           |0.254 ms(1K) 0.241 ms(2K)              |
|(don't move   |  162.1 FPS      |  42.15 us |0.230 ms(4K) 0.223 ms(8K) 0.204 ms(16K)|
|PT BOs on LRU)|                 |           |                                       |
+------------------------------------------------------------------------------------+
| Bulk move    |  163.1 FPS      |  40.52 us |0.244 ms(1K) 0.252 ms(2K) 0.213 ms(4K) |
|              |                 |           |0.214 ms(8K) 0.225 ms(16K)             |
+--------------+-----------------+-----------+---------------------------------------+

After test them with above three benchmarks include vulkan and opencl. We can
see the visible improvement than original, and even better than original with
workaround.

v2: move all BOs include idle, relocated, and moved list to the end of LRU and
put them together.
v3: remove unused parameter and use list_for_each_entry instead of the one with
save entry.
v4: move the amdgpu_vm_move_to_lru_tail after command submission, at that time,
all bo will be back on idle list.
v5: remove amdgpu_vm_move_to_lru_tail_by_list(), use bulk_moveable instread of
validated, and move ttm_bo_bulk_move_lru_tail() also into
amdgpu_vm_move_to_lru_tail().
v6: clean up and fix return value.

Change-Id: I51908d5affe817219d24ad0a1f5da289b2e9f560
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang@amd.com>
Acked-by: Chunming Zhou <david1.zhou@amd.com>
Tested-by: Mike Lothian <mike@fireburn.co.uk>
Tested-by: Dieter Nützel <Dieter@nuetzel-hh.de>
Signed-off-by: Kalyan Alle <kalyan.alle@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c |  3 ++
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 66 +++++++++++++++++---------
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 11 ++++-
 include/drm/ttm/ttm_bo_api.h           | 10 ++++
 include/drm/ttm/ttm_bo_driver.h        | 28 +++++++++++
 5 files changed, 95 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 3c1443d7fb84..8875c18dcfc0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -1274,6 +1274,7 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 	union drm_amdgpu_cs *cs = data;
 	struct amdgpu_cs_parser parser = {};
 	bool reserved_buffers = false;
+	struct amdgpu_fpriv *fpriv;
 	int i, r;
 
 	if (!adev->accel_working)
@@ -1318,6 +1319,8 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 
 	r = amdgpu_cs_submit(&parser, cs);
 
+	fpriv = filp->driver_priv;
+	amdgpu_vm_move_to_lru_tail(adev, &fpriv->vm);
 out:
 	amdgpu_cs_parser_fini(&parser, r, reserved_buffers);
 	return r;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 52b1cdea845a..617085b6e22c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -268,6 +268,47 @@ void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
 	list_add(&entry->tv.head, validated);
 }
 
+/**
+ * amdgpu_vm_move_to_lru_tail - move all BOs to the end of LRU
+ *
+ * @adev: amdgpu device pointer
+ * @vm: vm providing the BOs
+ *
+ * Move all BOs to the end of LRU and remember their positions to put them
+ * together.
+ */
+void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
+				struct amdgpu_vm *vm)
+{
+	struct ttm_bo_global *glob = adev->mman.bdev.glob;
+	struct amdgpu_vm_bo_base *bo_base;
+
+	if (vm->bulk_moveable) {
+		spin_lock(&glob->lru_lock);
+		ttm_bo_bulk_move_lru_tail(&vm->lru_bulk_move);
+		spin_unlock(&glob->lru_lock);
+		return;
+	}
+
+	memset(&vm->lru_bulk_move, 0, sizeof(vm->lru_bulk_move));
+
+	spin_lock(&glob->lru_lock);
+	list_for_each_entry(bo_base, &vm->idle, vm_status) {
+		struct amdgpu_bo *bo = bo_base->bo;
+
+		if (!bo->parent)
+			continue;
+
+		ttm_bo_move_to_lru_tail(&bo->tbo, &vm->lru_bulk_move);
+		if (bo->shadow)
+			ttm_bo_move_to_lru_tail(&bo->shadow->tbo,
+						&vm->lru_bulk_move);
+	}
+	spin_unlock(&glob->lru_lock);
+
+	vm->bulk_moveable = true;
+}
+
 /**
  * amdgpu_vm_validate_pt_bos - validate the page table BOs
  *
@@ -285,10 +326,11 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 			      int (*validate)(void *p, struct amdgpu_bo *bo),
 			      void *param)
 {
-	struct ttm_bo_global *glob = adev->mman.bdev.glob;
 	struct amdgpu_vm_bo_base *bo_base, *tmp;
 	int r = 0;
 
+	vm->bulk_moveable &= list_empty(&vm->evicted);
+
 	list_for_each_entry_safe(bo_base, tmp, &vm->evicted, vm_status) {
 		struct amdgpu_bo *bo = bo_base->bo;
 
@@ -296,14 +338,6 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 		if (r)
 			break;
 
-		if (bo->parent) {
-			spin_lock(&glob->lru_lock);
-			ttm_bo_move_to_lru_tail(&bo->tbo, NULL);
-			if (bo->shadow)
-				ttm_bo_move_to_lru_tail(&bo->shadow->tbo, NULL);
-			spin_unlock(&glob->lru_lock);
-		}
-
 		if (bo->tbo.type != ttm_bo_type_kernel) {
 			spin_lock(&vm->moved_lock);
 			list_move(&bo_base->vm_status, &vm->moved);
@@ -313,19 +347,6 @@ int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 		}
 	}
 
-	spin_lock(&glob->lru_lock);
-	list_for_each_entry(bo_base, &vm->idle, vm_status) {
-		struct amdgpu_bo *bo = bo_base->bo;
-
-		if (!bo->parent)
-			continue;
-
-		ttm_bo_move_to_lru_tail(&bo->tbo, NULL);
-		if (bo->shadow)
-			ttm_bo_move_to_lru_tail(&bo->shadow->tbo, NULL);
-	}
-	spin_unlock(&glob->lru_lock);
-
 	return r;
 }
 
@@ -2639,6 +2660,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 		return r;
 
 	vm->pte_support_ats = false;
+	vm->bulk_moveable = true;
 
 	if (vm_context == AMDGPU_VM_CONTEXT_COMPUTE) {
 		vm->use_cpu_for_update = !!(adev->vm_manager.vm_update_mode &
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index ab1d23e4b8ad..7a461eb76d44 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -29,6 +29,7 @@
 #include <linux/rbtree.h>
 #include <drm/gpu_scheduler.h>
 #include <drm/drm_file.h>
+#include <drm/ttm/ttm_bo_driver.h>
 
 #include "amdgpu_sync.h"
 #include "amdgpu_ring.h"
@@ -247,6 +248,11 @@ struct amdgpu_vm {
 
 	/* Some basic info about the task */
 	struct amdgpu_task_info task_info;
+
+	/* Store positions of group of BOs */
+	struct ttm_lru_bulk_move lru_bulk_move;
+	/* mark whether can do the bulk move */
+	bool			bulk_moveable;
 };
 
 struct amdgpu_vm_manager {
@@ -354,8 +360,11 @@ bool amdgpu_vm_need_pipeline_sync(struct amdgpu_ring *ring,
 void amdgpu_vm_check_compute_bug(struct amdgpu_device *adev);
 
 void amdgpu_vm_get_task_info(struct amdgpu_device *adev, unsigned int pasid,
-			 struct amdgpu_task_info *task_info);
+			     struct amdgpu_task_info *task_info);
 
 void amdgpu_vm_set_task_info(struct amdgpu_vm *vm);
 
+void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
+				struct amdgpu_vm *vm);
+
 #endif
diff --git a/include/drm/ttm/ttm_bo_api.h b/include/drm/ttm/ttm_bo_api.h
index 92d0a1e892c3..e6955ce24d73 100644
--- a/include/drm/ttm/ttm_bo_api.h
+++ b/include/drm/ttm/ttm_bo_api.h
@@ -417,6 +417,16 @@ void ttm_bo_del_from_lru(struct ttm_buffer_object *bo);
 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
                              struct ttm_lru_bulk_move *bulk);
 
+/**
+ * ttm_bo_bulk_move_lru_tail
+ *
+ * @bulk: bulk move structure
+ *
+ * Bulk move BOs to the LRU tail, only valid to use when driver makes sure that
+ * BO order never changes. Should be called with ttm_bo_global::lru_lock held.
+ */
+void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk);
+
 /**
  * ttm_bo_lock_delayed_workqueue
  *
diff --git a/include/drm/ttm/ttm_bo_driver.h b/include/drm/ttm/ttm_bo_driver.h
index 3234cc322e70..17e20781ca7a 100644
--- a/include/drm/ttm/ttm_bo_driver.h
+++ b/include/drm/ttm/ttm_bo_driver.h
@@ -490,6 +490,34 @@ struct ttm_bo_device {
 	bool no_retry;
 };
 
+/**
+ * struct ttm_lru_bulk_move_pos
+ *
+ * @first: first BO in the bulk move range
+ * @last: last BO in the bulk move range
+ *
+ * Positions for a lru bulk move.
+ */
+struct ttm_lru_bulk_move_pos {
+        struct ttm_buffer_object *first;
+        struct ttm_buffer_object *last;
+};
+
+/**
+ * struct ttm_lru_bulk_move
+ *
+ * @tt: first/last lru entry for BOs in the TT domain
+ * @vram: first/last lru entry for BOs in the VRAM domain
+ * @swap: first/last lru entry for BOs on the swap list
+ *
+ * Helper structure for bulk moves on the LRU list.
+ */
+struct ttm_lru_bulk_move {
+        struct ttm_lru_bulk_move_pos tt[TTM_MAX_BO_PRIORITY];
+        struct ttm_lru_bulk_move_pos vram[TTM_MAX_BO_PRIORITY];
+        struct ttm_lru_bulk_move_pos swap[TTM_MAX_BO_PRIORITY];
+};
+
 /**
  * ttm_flag_masked
  *
-- 
2.17.1