drm/amdgpu: use only one reservation object for each VM v2

Reduces the locking and fencing overhead.

v2: add comment why we need the duplicates list in the GEM op.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index b75c3b2..2f39fea 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -455,11 +455,12 @@ static void amdgpu_gem_va_update_vm(struct amdgpu_device *adev,
        struct ttm_validate_buffer tv, *entry;
        struct amdgpu_bo_list_entry *vm_bos;
        struct ww_acquire_ctx ticket;
-       struct list_head list;
+       struct list_head list, duplicates;
        unsigned domain;
        int r;
 
        INIT_LIST_HEAD(&list);
+       INIT_LIST_HEAD(&duplicates);
 
        tv.bo = &bo_va->bo->tbo;
        tv.shared = true;
@@ -469,7 +470,8 @@ static void amdgpu_gem_va_update_vm(struct amdgpu_device *adev,
        if (!vm_bos)
                return;
 
-       r = ttm_eu_reserve_buffers(&ticket, &list, true, NULL);
+       /* Provide duplicates to avoid -EALREADY */
+       r = ttm_eu_reserve_buffers(&ticket, &list, true, &duplicates);
        if (r)
                goto error_free;
 

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 8927dc6..d30fbec 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -686,31 +686,6 @@ static int amdgpu_vm_update_ptes(struct amdgpu_device *adev,
 }
 
 /**
- * amdgpu_vm_fence_pts - fence page tables after an update
- *
- * @vm: requested vm
- * @start: start of GPU address range
- * @end: end of GPU address range
- * @fence: fence to use
- *
- * Fence the page tables in the range @start - @end (cayman+).
- *
- * Global and local mutex must be locked!
- */
-static void amdgpu_vm_fence_pts(struct amdgpu_vm *vm,
-                               uint64_t start, uint64_t end,
-                               struct fence *fence)
-{
-       unsigned i;
-
-       start >>= amdgpu_vm_block_size;
-       end >>= amdgpu_vm_block_size;
-
-       for (i = start; i <= end; ++i)
-               amdgpu_bo_fence(vm->page_tables[i].bo, fence, true);
-}
-
-/**
  * amdgpu_vm_bo_update_mapping - update a mapping in the vm page table
  *
  * @adev: amdgpu_device pointer
@@ -813,8 +788,7 @@ static int amdgpu_vm_bo_update_mapping(struct amdgpu_device *adev,
        if (r)
                goto error_free;
 
-       amdgpu_vm_fence_pts(vm, mapping->it.start,
-                           mapping->it.last + 1, f);
+       amdgpu_bo_fence(vm->page_directory, f, true);
        if (fence) {
                fence_put(*fence);
                *fence = fence_get(f);
@@ -1089,6 +1063,7 @@ int amdgpu_vm_bo_map(struct amdgpu_device *adev,
 
        /* walk over the address space and allocate the page tables */
        for (pt_idx = saddr; pt_idx <= eaddr; ++pt_idx) {
+               struct reservation_object *resv = vm->page_directory->tbo.resv;
                struct amdgpu_bo *pt;
 
                if (vm->page_tables[pt_idx].bo)
@@ -1097,11 +1072,13 @@ int amdgpu_vm_bo_map(struct amdgpu_device *adev,
                /* drop mutex to allocate and clear page table */
                mutex_unlock(&vm->mutex);
 
+               ww_mutex_lock(&resv->lock, NULL);
                r = amdgpu_bo_create(adev, AMDGPU_VM_PTE_COUNT * 8,
                                     AMDGPU_GPU_PAGE_SIZE, true,
                                     AMDGPU_GEM_DOMAIN_VRAM,
                                     AMDGPU_GEM_CREATE_NO_CPU_ACCESS,
-                                    NULL, NULL, &pt);
+                                    NULL, resv, &pt);
+               ww_mutex_unlock(&resv->lock);
                if (r)
                        goto error_free;