path: root/common/recipes-kernel/linux/linux-yocto-4.14.71/1462-drm-amdkfd-pin-unpin-PTs-PD-only-once-instead-of-per.patch

From 8a2329c9bd41d645d52c9f5e1e108251d55d74c5 Mon Sep 17 00:00:00 2001
From: Yong Zhao <yong.zhao@amd.com>
Date: Fri, 24 Jun 2016 18:06:58 -0400
Subject: [PATCH 1462/4131] drm/amdkfd: pin/unpin PTs/PD only once instead of
 per mapping

amdgpu requires all PT BOs to be in VRAM when updating page table
entries, so we should pin all PT BOs instead of just the ones
corresponding to BO being mapped. Therefore, we statically pin PD
right after it is allocated and incrementally pin PTs in map when
needed, and they are all unpinned only when the process exits.

Change-Id: I514c0ae5c071341feff90ed7cee799727f6b2e06
Signed-off-by: Yong Zhao <yong.zhao@amd.com>

 Conflicts:
	drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 143 ++++++++---------------
 1 file changed, 51 insertions(+), 92 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 7b119e8..2725393 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -196,86 +196,42 @@ static int unpin_bo(struct amdgpu_bo *bo)
 	return ret;
 }
 
-
-static int try_pin_pts(struct amdgpu_bo_va *bo_va)
+static int try_pin_pts(struct amdgpu_vm *vm)
 {
-	int ret;
-	uint64_t pt_idx, start, last, failed;
-	struct amdgpu_vm *vm;
-	struct amdgpu_bo_va_mapping *mapping;
-
-	vm = bo_va->vm;
-	list_for_each_entry(mapping, &bo_va->valids, list) {
-		start = mapping->it.start >> amdgpu_vm_block_size;
-		last = mapping->it.last >> amdgpu_vm_block_size;
-
-		pr_debug("start PT index %llu  last PT index %llu\n", start, last);
-
-		/* walk over the address space and pin the page tables BOs*/
-		for (pt_idx = start; pt_idx <= last; pt_idx++) {
-			ret = try_pin_bo(vm->page_tables[pt_idx].bo,
-					AMDGPU_GEM_DOMAIN_VRAM);
-			if (ret != 0) {
-				failed = pt_idx;
-				goto err;
-			}
-		}
-	}
+	int i, ret = 0;
+	struct amdgpu_bo *bo;
 
-	list_for_each_entry(mapping, &bo_va->invalids, list) {
-		start = mapping->it.start >> amdgpu_vm_block_size;
-		last = mapping->it.last >> amdgpu_vm_block_size;
+	/* only pin PTs not yet pinned*/
+	for (i = 0; i <= vm->max_pde_used; ++i) {
+		bo = vm->page_tables[i].entry.robj;
 
-		pr_debug("start PT index %llu  last PT index %llu\n", start, last);
+		if (!bo || bo->pin_count)
+			continue;
 
-		/* walk over the address space and pin the page tables BOs*/
-		for (pt_idx = start; pt_idx <= last; pt_idx++) {
-			ret = try_pin_bo(vm->page_tables[pt_idx].bo,
-					AMDGPU_GEM_DOMAIN_VRAM);
-			if (ret != 0) {
-				failed = pt_idx;
-				goto err;
-			}
+		ret = try_pin_bo(bo, AMDGPU_GEM_DOMAIN_VRAM);
+		if (ret != 0) {
+			pr_err("amdgpu: failed to pin PTE %d\n", i);
+			break;
 		}
 	}
 
-	return 0;
-
-err:
-	pr_err("amdgpu: Failed to pin BO's PTEs\n");
-	/* Unpin all already pinned BOs*/
-	if (failed > 0) {
-		for (pt_idx = start; pt_idx <= failed - 1; pt_idx++)
-			unpin_bo(vm->page_tables[pt_idx].bo);
-	}
 	return ret;
 }
 
-static void unpin_pts(struct amdgpu_bo_va *bo_va, struct amdgpu_vm *vm)
+static void unpin_pts(struct amdgpu_vm *vm)
 {
-	uint64_t pt_idx, start, last;
-	struct amdgpu_bo_va_mapping *mapping;
-
-	list_for_each_entry(mapping, &bo_va->valids, list) {
-		start = mapping->it.start >> amdgpu_vm_block_size;
-		last = mapping->it.last >> amdgpu_vm_block_size;
-
-		pr_debug("start PT index %llu  last PT index %llu\n", start, last);
-
-		/* walk over the address space and unpin the page tables BOs*/
-		for (pt_idx = start; pt_idx <= last; pt_idx++)
-			unpin_bo(vm->page_tables[pt_idx].bo);
-	}
+	int i;
+	struct amdgpu_bo *bo;
 
-	list_for_each_entry(mapping, &bo_va->invalids, list) {
-		start = mapping->it.start >> amdgpu_vm_block_size;
-		last = mapping->it.last >> amdgpu_vm_block_size;
+	for (i = vm->max_pde_used; i >= 0; --i) {
+		bo = vm->page_tables[i].entry.robj;
 
-		pr_debug("start PT index %llu  last PT index %llu\n", start, last);
+		if (!bo || !bo->pin_count)
+			continue;
 
-		/* walk over the address space and unpin the page tables BOs*/
-		for (pt_idx = start; pt_idx <= last; pt_idx++)
-			unpin_bo(vm->page_tables[pt_idx].bo);
+		amdgpu_bo_reserve(bo, true);
+		unpin_bo(bo);
+		amdgpu_bo_unreserve(bo);
 	}
 }
 
@@ -742,8 +698,9 @@ static int map_bo_to_gpuvm(struct amdgpu_device *adev, struct amdgpu_bo *bo,
 	int ret;
 
 	/*
-	 * We need to pin the allocated BO, PD and appropriate PTs and to
-	 * create a mapping of virtual to MC address
+	 * We need to pin the allocated BO and PTs not yet pinned to
+	 * create a mapping of virtual to MC address. PD is already pinned
+	 * in amdgpu_amdkfd_gpuvm_create_process_vm().
 	 */
 	/* Pin BO*/
 	ret = try_pin_bo(bo, domain);
@@ -752,26 +709,19 @@ static int map_bo_to_gpuvm(struct amdgpu_device *adev, struct amdgpu_bo *bo,
 		return ret;
 	}
 
+	vm = bo_va->vm;
 	/* Pin PTs */
-	ret = try_pin_pts(bo_va);
+	ret = try_pin_pts(vm);
 	if (ret != 0) {
 		pr_err("amdkfd: Failed to pin PTs\n");
-		goto err_failed_to_pin_pts;
-	}
-
-	/* Pin the PD directory*/
-	vm = bo_va->vm;
-	ret = try_pin_bo(vm->page_directory, AMDGPU_GEM_DOMAIN_VRAM);
-	if (ret != 0) {
-		pr_err("amdkfd: Failed to pin PD\n");
-		goto err_failed_to_pin_pd;
+		goto err_unpin_bo;
 	}
 
 	/* Update the page directory */
 	ret = amdgpu_vm_update_page_directory(adev, vm);
 	if (ret != 0) {
 		pr_err("amdkfd: Failed to radeon_vm_update_page_directory\n");
-		goto err_failed_to_update_pd;
+		goto err_unpin_bo;
 	}
 
 	/*
@@ -782,14 +732,14 @@ static int map_bo_to_gpuvm(struct amdgpu_device *adev, struct amdgpu_bo *bo,
 	ret = amdgpu_vm_clear_freed(adev, vm);
 	if (ret != 0) {
 		pr_err("amdkfd: Failed to radeon_vm_clear_freed\n");
-		goto err_failed_vm_clear_freed;
+		goto err_unpin_bo;
 	}
 
 	/* Update the page tables  */
 	ret = amdgpu_vm_bo_update(adev, bo_va, &bo->tbo.mem);
 	if (ret != 0) {
 		pr_err("amdkfd: Failed to radeon_vm_bo_update\n");
-		goto err_failed_to_update_pts;
+		goto err_unpin_bo;
 	}
 
 	ret = amdgpu_vm_clear_invalids(adev, vm, NULL);
@@ -805,13 +755,8 @@ static int map_bo_to_gpuvm(struct amdgpu_device *adev, struct amdgpu_bo *bo,
 
 err_failed_to_vm_clear_invalids:
 	amdgpu_vm_bo_update(adev, bo_va, NULL);
-err_failed_to_update_pts:
-err_failed_vm_clear_freed:
-err_failed_to_update_pd:
-	unpin_bo(vm->page_directory);
-err_failed_to_pin_pd:
-	unpin_pts(bo_va, vm);
-err_failed_to_pin_pts:
+err_unpin_bo:
+	/* PTs are not needed to be unpinned*/
 	unpin_bo(bo);
 
 	return ret;
@@ -1055,6 +1000,7 @@ int amdgpu_amdkfd_gpuvm_create_process_vm(struct kgd_dev *kgd, void **vm)
 {
 	int ret;
 	struct amdgpu_vm *new_vm;
+	struct amdgpu_bo *pd;
 	struct amdgpu_device *adev = get_amdgpu_device(kgd);
 
 	BUG_ON(kgd == NULL);
@@ -1085,6 +1031,14 @@ int amdgpu_amdkfd_gpuvm_create_process_vm(struct kgd_dev *kgd, void **vm)
 	if (ret != 0)
 		pr_err("amdgpu: Failed to amdgpu_vm_clear_freed\n");
 
+	/* Pin the PD directory */
+	pd = new_vm->page_directory;
+	amdgpu_bo_reserve(pd, true);
+	ret = try_pin_bo(pd, AMDGPU_GEM_DOMAIN_VRAM);
+	amdgpu_bo_unreserve(pd);
+	if (ret != 0)
+		pr_err("amdkfd: Failed to pin PD\n");
+
 	pr_debug("amdgpu: created process vm with address 0x%llx\n",
 			amdgpu_bo_gpu_offset(new_vm->page_directory));
 
@@ -1095,12 +1049,21 @@ void amdgpu_amdkfd_gpuvm_destroy_process_vm(struct kgd_dev *kgd, void *vm)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *) kgd;
 	struct amdgpu_vm *avm = (struct amdgpu_vm *) vm;
+	struct amdgpu_bo *pd;
 
 	BUG_ON(kgd == NULL);
 	BUG_ON(vm == NULL);
 
 	pr_debug("Destroying process vm with address %p\n", vm);
 
+	/* Unpin PTs */
+	unpin_pts(avm);
+	/* Unpin PD*/
+	pd = avm->page_directory;
+	amdgpu_bo_reserve(pd, true);
+	unpin_bo(pd);
+	amdgpu_bo_unreserve(pd);
+
 	/* Release the VM context */
 	amdgpu_vm_fini(adev, avm);
 	kfree(vm);
@@ -1149,10 +1112,6 @@ static int unmap_bo_from_gpuvm(struct amdgpu_device *adev,
 
 	amdgpu_vm_clear_invalids(adev, vm, NULL);
 
-	/* Unpin the PD directory*/
-	unpin_bo(bo_va->vm->page_directory);
-	/* Unpin PTs */
-	unpin_pts(bo_va, bo_va->vm);
 	/* Unpin BO*/
 	unpin_bo(bo);
 
-- 
2.7.4