We only need the page array when the BO is about to be accessed.

So not only populate, but also create it on demand.

v2: move NULL check into ttm_tt_create()

Signed-off-by: Christian König christian.koenig@amd.com --- drivers/gpu/drm/ttm/ttm_bo.c | 37 ++++++++----------------------- drivers/gpu/drm/ttm/ttm_bo_util.c | 9 ++++++-- drivers/gpu/drm/ttm/ttm_bo_vm.c | 5 +++++ drivers/gpu/drm/ttm/ttm_tt.c | 4 +++- 4 files changed, 24 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 06b8bc0d8f23..c8c25e45751a 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -292,12 +292,11 @@ static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo, */

if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) { - if (bo->ttm == NULL) { - bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED); - ret = ttm_tt_create(bo, zero); - if (ret) - goto out_err; - } + bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED); + + ret = ttm_tt_create(bo, zero); + if (ret) + goto out_err;

ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement); if (ret) @@ -660,13 +659,8 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo, placement.num_busy_placement = 0; bdev->driver->evict_flags(bo, &placement);

- if (!placement.num_placement && !placement.num_busy_placement) { - ret = ttm_bo_pipeline_gutting(bo); - if (ret) - return ret; - - return ttm_tt_create(bo, false); - } + if (!placement.num_placement && !placement.num_busy_placement) + return ttm_bo_pipeline_gutting(bo);

evict_mem = bo->mem; evict_mem.mm_node = NULL; @@ -1194,13 +1188,8 @@ int ttm_bo_validate(struct ttm_buffer_object *bo, /* * Remove the backing store if no placement is given. */ - if (!placement->num_placement && !placement->num_busy_placement) { - ret = ttm_bo_pipeline_gutting(bo); - if (ret) - return ret; - - return ttm_tt_create(bo, false); - } + if (!placement->num_placement && !placement->num_busy_placement) + return ttm_bo_pipeline_gutting(bo);

/* * Check whether we need to move buffer. @@ -1217,14 +1206,6 @@ int ttm_bo_validate(struct ttm_buffer_object *bo, ttm_flag_masked(&bo->mem.placement, new_flags, ~TTM_PL_MASK_MEMTYPE); } - /* - * We might need to add a TTM. - */ - if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) { - ret = ttm_tt_create(bo, true); - if (ret) - return ret; - } return 0; } EXPORT_SYMBOL(ttm_bo_validate); diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 52d2b71f1588..f8414f820350 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -580,12 +580,17 @@ static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo, .interruptible = false, .no_wait_gpu = false }; - struct ttm_tt *ttm = bo->ttm; + struct ttm_tt *ttm; pgprot_t prot; int ret;

- BUG_ON(!ttm); + if (!bo->ttm) { + ret = ttm_tt_create(bo, true); + if (ret) + return ret; + }

+ ttm = bo->ttm; ret = ttm_tt_populate(ttm, &ctx); if (ret) return ret; diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 0ad30b112982..0586870ab642 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -349,6 +349,11 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,

};

+ if (ttm_tt_create(bo, true)) { + ret = VM_FAULT_OOM; + goto out_io_unlock; + } + ttm = bo->ttm; if (ttm_tt_populate(bo->ttm, &ctx)) { ret = VM_FAULT_OOM; diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index 2ec448e1d663..e25d4097aa16 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -50,6 +50,9 @@ int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)

dma_resv_assert_held(bo->base.resv);

+ if (bo->ttm) + return 0; + if (bdev->need_dma32) page_flags |= TTM_PAGE_FLAG_DMA32;

@@ -67,7 +70,6 @@ int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc) page_flags |= TTM_PAGE_FLAG_SG; break; default: - bo->ttm = NULL; pr_err("Illegal buffer object type\n"); return -EINVAL; }

-----Original Message----- From: dri-devel dri-devel-bounces@lists.freedesktop.org On Behalf Of Christian König Sent: Monday, June 29, 2020 8:22 AM To: dri-devel@lists.freedesktop.org Subject: [PATCH 1/2] drm/ttm: cleanup ttm_mem_type_manager_func.get_node interface v2

Instead of signaling failure by setting the node pointer to NULL do so by returning -ENOSPC.

v2: add memset() to make sure that mem is always initialized.

Signed-off-by: Christian König christian.koenig@amd.com

drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c | 4 +--- drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 5 ++--- drivers/gpu/drm/nouveau/nouveau_ttm.c | 8 -------- drivers/gpu/drm/ttm/ttm_bo.c | 12 ++++++------ drivers/gpu/drm/ttm/ttm_bo_manager.c | 2 +- drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c | 4 +--- 6 files changed, 11 insertions(+), 24 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c index 627104401e84..2baa80224fa4 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c @@ -229,7 +229,7 @@ static int amdgpu_gtt_mgr_new(struct ttm_mem_type_manager *man, if ((&tbo->mem == mem || tbo->mem.mem_type != TTM_PL_TT) && atomic64_read(&mgr->available) < mem->num_pages) { spin_unlock(&mgr->lock);

• return 0;
  

• return -ENOSPC;
  

  } atomic64_sub(mem->num_pages, &mgr->available); spin_unlock(&mgr->lock);

@@ -249,8 +249,6 @@ static int amdgpu_gtt_mgr_new(struct ttm_mem_type_manager *man, r = amdgpu_gtt_mgr_alloc(man, tbo, place, mem); if (unlikely(r)) { kfree(node);

• 	mem->mm_node = NULL;
  

• 	r = 0;
  

I think that this one is still a problem. The code path sets:

mem->mm_node = node;

(about 3 lines above this chunk, and then calls

amdgpu_gtt_mgr_malloc()

If amdgpu_gtt_mgr_malloc() fails, mm_node is still set. I think you need to keep this mm_node = NULL setting, or the path needs to be modified to not set mm_node.

	goto err_out;
}

} else { diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c index 128a667ed8fa..e8d1dd564006 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c @@ -336,8 +336,7 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man, mem_bytes = (u64)mem->num_pages << PAGE_SHIFT; if (atomic64_add_return(mem_bytes, &mgr->usage) > max_bytes) { atomic64_sub(mem_bytes, &mgr->usage);

• mem->mm_node = NULL;
  

• return 0;
  

• return -ENOSPC;
  

  }

  if (place->flags & TTM_PL_FLAG_CONTIGUOUS) {

@@ -417,7 +416,7 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man, atomic64_sub(mem->num_pages << PAGE_SHIFT, &mgr->usage);

kvfree(nodes);

• return r == -ENOSPC ? 0 : r;

• return r;

}

/** diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c b/drivers/gpu/drm/nouveau/nouveau_ttm.c index 7ca0a2498532..e89ea052cf71 100644 --- a/drivers/gpu/drm/nouveau/nouveau_ttm.c +++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c @@ -75,10 +75,6 @@ nouveau_vram_manager_new(struct ttm_mem_type_manager *man, ret = nouveau_mem_vram(reg, nvbo->contig, nvbo->page); if (ret) { nouveau_mem_del(reg);

• if (ret == -ENOSPC) {
  

• 	reg->mm_node = NULL;
  

• 	return 0;
  

• }
  

  return ret; }

@@ -139,10 +135,6 @@ nv04_gart_manager_new(struct ttm_mem_type_manager *man, reg->num_pages << PAGE_SHIFT, &mem->vma[0]); if (ret) { nouveau_mem_del(reg);

• if (ret == -ENOSPC) {
  

• 	reg->mm_node = NULL;
  

• 	return 0;
  

• }
  

  return ret; }

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index f78cfc76ad78..06b8bc0d8f23 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -909,10 +909,10 @@ static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo, ticket = dma_resv_locking_ctx(bo->base.resv); do { ret = (*man->func->get_node)(man, bo, place, mem);

• if (unlikely(ret != 0))
  

• 	return ret;
  

• if (mem->mm_node)
  

• if (likely(!ret))
  break;
  

• if (unlikely(ret != -ENOSPC))
  

• 	return ret;
  

  ret = ttm_mem_evict_first(bdev, mem->mem_type, place,

ctx, ticket); if (unlikely(ret != 0)) @@ -1056,12 +1056,11 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,

man = &bdev->man[mem->mem_type];
ret = (*man->func->get_node)(man, bo, place, mem);

• if (ret == -ENOSPC)
  

• 	continue;
  

  if (unlikely(ret)) goto error;

• if (!mem->mm_node)
  

• 	continue;
  

• ret = ttm_bo_add_move_fence(bo, man, mem, ctx-

...

no_wait_gpu);

if (unlikely(ret)) {
	(*man->func->put_node)(man, mem);

@@ -1121,6 +1120,7 @@ static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,

dma_resv_assert_held(bo->base.resv);

• memset(&mem, 0, sizeof(mem));

I missed this completely. Setting this here:

mm.mm_node = NULL;

is probably sufficient. The other call sites do this instead of the memset().

Mike

mem.num_pages = bo->num_pages; mem.size = mem.num_pages << PAGE_SHIFT; mem.page_alignment = bo->mem.page_alignment; diff --git a/drivers/gpu/drm/ttm/ttm_bo_manager.c b/drivers/gpu/drm/ttm/ttm_bo_manager.c index 18d3debcc949..facd3049c3aa 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_manager.c +++ b/drivers/gpu/drm/ttm/ttm_bo_manager.c @@ -86,7 +86,7 @@ static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man, mem->start = node->start; }

• return 0;

• return ret;

}

static void ttm_bo_man_put_node(struct ttm_mem_type_manager *man, diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c b/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c index 7da752ca1c34..4a76fc7114ad 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c @@ -53,8 +53,6 @@ static int vmw_gmrid_man_get_node(struct ttm_mem_type_manager *man, (struct vmwgfx_gmrid_man *)man->priv; int id;

• mem->mm_node = NULL;
• id = ida_alloc_max(&gman->gmr_ida, gman->max_gmr_ids - 1,

GFP_KERNEL); if (id < 0) return (id != -ENOMEM ? 0 : id); @@ -78,7 +76,7 @@ static int vmw_gmrid_man_get_node(struct ttm_mem_type_manager *man, gman->used_gmr_pages -= bo->num_pages; spin_unlock(&gman->lock); ida_free(&gman->gmr_ida, id);

• return 0;

• return -ENOSPC;

}

static void vmw_gmrid_man_put_node(struct ttm_mem_type_manager

*man,

2.17.1

---

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