[PATCH 2/2] drm/amdgpu: replace get_user_pages with HMM address mirror helpers v2

Yang, Philip Philip.Yang at amd.com
Mon Dec 3 20:19:08 UTC 2018


Use HMM helper function hmm_vma_fault() to get physical pages backing
userptr and start CPU page table update track of those pages. Then use
hmm_vma_range_done() to check if those pages are updated before
amdgpu_cs_submit for gfx or before user queues are resumed for kfd.

If userptr pages are updated, for gfx, amdgpu_cs_ioctl will restart
from scratch, for kfd, restore worker is rescheduled to retry.

To avoid circular lock dependency, no nested locking between mmap_sem
and bo::reserve. The locking order is:
bo::reserve -> amdgpu_mn_lock(p->mn)

HMM simplify the CPU page table concurrent update check, so remove
guptasklock, mmu_invalidations, last_set_pages fields from
amdgpu_ttm_tt struct.

HMM does not pin the page (increase page ref count), so remove related
operations like release_pages(), put_page(), mark_page_dirty().

v2:
* Remove nested locking between mmap_sem and bo::reserve
* Change locking order to bo::reserve -> amdgpu_mn_lock()
* Use dynamic allocation to replace VLA in kernel stack

Change-Id: Iffd5f855cc9ce402cdfca167f68f83fe39ac56f9
Signed-off-by: Philip Yang <Philip.Yang at amd.com>
---
 .../gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c  | 101 ++++++++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c   |   2 -
 drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h   |   3 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c        | 188 +++++++++---------
 drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c       |  14 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c        |  34 +++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h        |   7 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c       | 164 ++++++---------
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h       |   3 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c        |   1 -
 .../drm/amd/amdkfd/kfd_device_queue_manager.c |  67 ++++---
 11 files changed, 312 insertions(+), 272 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index f3129b912714..5ce6ba24fc72 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -614,8 +614,7 @@ static int init_user_pages(struct kgd_mem *mem, struct mm_struct *mm,
 	amdgpu_bo_unreserve(bo);
 
 release_out:
-	if (ret)
-		release_pages(mem->user_pages, bo->tbo.ttm->num_pages);
+	amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
 free_out:
 	kvfree(mem->user_pages);
 	mem->user_pages = NULL;
@@ -677,7 +676,6 @@ static int reserve_bo_and_vm(struct kgd_mem *mem,
 	ctx->kfd_bo.priority = 0;
 	ctx->kfd_bo.tv.bo = &bo->tbo;
 	ctx->kfd_bo.tv.shared = true;
-	ctx->kfd_bo.user_pages = NULL;
 	list_add(&ctx->kfd_bo.tv.head, &ctx->list);
 
 	amdgpu_vm_get_pd_bo(vm, &ctx->list, &ctx->vm_pd[0]);
@@ -741,7 +739,6 @@ static int reserve_bo_and_cond_vms(struct kgd_mem *mem,
 	ctx->kfd_bo.priority = 0;
 	ctx->kfd_bo.tv.bo = &bo->tbo;
 	ctx->kfd_bo.tv.shared = true;
-	ctx->kfd_bo.user_pages = NULL;
 	list_add(&ctx->kfd_bo.tv.head, &ctx->list);
 
 	i = 0;
@@ -1332,9 +1329,6 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
 	/* Free user pages if necessary */
 	if (mem->user_pages) {
 		pr_debug("%s: Freeing user_pages array\n", __func__);
-		if (mem->user_pages[0])
-			release_pages(mem->user_pages,
-					mem->bo->tbo.ttm->num_pages);
 		kvfree(mem->user_pages);
 	}
 
@@ -1761,8 +1755,6 @@ static int update_invalid_user_pages(struct amdkfd_process_info *process_info,
 				       __func__);
 				return -ENOMEM;
 			}
-		} else if (mem->user_pages[0]) {
-			release_pages(mem->user_pages, bo->tbo.ttm->num_pages);
 		}
 
 		/* Get updated user pages */
@@ -1778,12 +1770,6 @@ static int update_invalid_user_pages(struct amdkfd_process_info *process_info,
 			 * stalled user mode queues.
 			 */
 		}
-
-		/* Mark the BO as valid unless it was invalidated
-		 * again concurrently
-		 */
-		if (atomic_cmpxchg(&mem->invalid, invalid, 0) != invalid)
-			return -EAGAIN;
 	}
 
 	return 0;
@@ -1876,14 +1862,10 @@ static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
 		}
 
 		/* Validate succeeded, now the BO owns the pages, free
-		 * our copy of the pointer array. Put this BO back on
-		 * the userptr_valid_list. If we need to revalidate
-		 * it, we need to start from scratch.
+		 * our copy of the pointer array.
 		 */
 		kvfree(mem->user_pages);
 		mem->user_pages = NULL;
-		list_move_tail(&mem->validate_list.head,
-			       &process_info->userptr_valid_list);
 
 		/* Update mapping. If the BO was not validated
 		 * (because we couldn't get user pages), this will
@@ -1924,6 +1906,70 @@ static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
 	return ret;
 }
 
+/* user_pages_invalidated - if CPU page table is updated after getting user
+ * pages
+ *
+ * HMM mirror callback lock amn is hold to prevent the concurrent CPU
+ * page table update while resuming user queues.
+ *
+ * Returns: true if CPU page table is updated, false otherwise
+ */
+static int user_pages_invalidated(struct mm_struct *mm,
+			struct amdkfd_process_info *process_info,
+			struct amdgpu_mn **amn)
+{
+	struct kgd_mem *mem, *tmp_mem;
+	struct amdgpu_bo *bo;
+	struct amdgpu_device *adev;
+	int invalid, r = 0;
+
+	list_for_each_entry_safe(mem, tmp_mem,
+				 &process_info->userptr_inval_list,
+				 validate_list.head) {
+
+		invalid = atomic_read(&mem->invalid);
+		if (!invalid)
+			/* BO hasn't been invalidated since the last
+			 * revalidation attempt. Keep its BO list.
+			 */
+			continue;
+
+		bo = mem->bo;
+
+		/* Get HMM mirror callback lock */
+		if (!*amn) {
+			adev = amdgpu_ttm_adev(bo->tbo.bdev);
+			*amn = amdgpu_mn_get(mm, adev, AMDGPU_MN_TYPE_HSA);
+			if (IS_ERR(*amn)) {
+				r = true;
+				*amn = NULL;
+				goto out;
+			}
+
+			amdgpu_mn_lock(*amn);
+		}
+
+		r |= amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
+
+		/* Put this BO back on the userptr_valid_list. If we need to
+		 * revalidate it, we need to start from scratch.
+		 */
+		list_move_tail(&mem->validate_list.head,
+			       &process_info->userptr_valid_list);
+
+		/* Mark the BO as valid unless it was invalidated
+		 * again concurrently
+		 */
+		if (atomic_cmpxchg(&mem->invalid, invalid, 0) != invalid) {
+			r = true;
+			goto out;
+		}
+	}
+
+out:
+	return r;
+}
+
 /* Worker callback to restore evicted userptr BOs
  *
  * Tries to update and validate all userptr BOs. If successful and no
@@ -1939,6 +1985,7 @@ static void amdgpu_amdkfd_restore_userptr_worker(struct work_struct *work)
 	struct task_struct *usertask;
 	struct mm_struct *mm;
 	int evicted_bos;
+	struct amdgpu_mn *amn = NULL;
 
 	evicted_bos = atomic_read(&process_info->evicted_bos);
 	if (!evicted_bos)
@@ -1977,13 +2024,27 @@ static void amdgpu_amdkfd_restore_userptr_worker(struct work_struct *work)
 	if (atomic_cmpxchg(&process_info->evicted_bos, evicted_bos, 0) !=
 	    evicted_bos)
 		goto unlock_out;
+
+	/* If CPU page table is updated again after getting user pages,
+	 * schedule to restart the restore process again.
+	 *
+	 * amn is also locked to prevent CPU page table update while resuming
+	 * user queues. amn is unlocked after user queues are resumed.
+	 */
+	if (user_pages_invalidated(mm, process_info, &amn))
+		goto unlock_mn_out;
+
 	evicted_bos = 0;
+
 	if (kgd2kfd->resume_mm(mm)) {
 		pr_err("%s: Failed to resume KFD\n", __func__);
 		/* No recovery from this failure. Probably the CP is
 		 * hanging. No point trying again.
 		 */
 	}
+
+unlock_mn_out:
+	amdgpu_mn_unlock(amn);
 unlock_out:
 	mutex_unlock(&process_info->lock);
 	mmput(mm);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
index 14d2982a47cc..2716c241f57e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
@@ -201,8 +201,6 @@ void amdgpu_bo_list_get_list(struct amdgpu_bo_list *list,
 
 		if (!bo->parent)
 			list_add_tail(&e->tv.head, &bucket[priority]);
-
-		e->user_pages = NULL;
 	}
 
 	/* Connect the sorted buckets in the output list. */
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h
index 7c5f5d1601e6..4beab2de09b3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h
@@ -35,8 +35,7 @@ struct amdgpu_bo_list_entry {
 	struct ttm_validate_buffer	tv;
 	struct amdgpu_bo_va		*bo_va;
 	uint32_t			priority;
-	struct page			**user_pages;
-	int				user_invalidated;
+	bool				user_invalidated;
 };
 
 struct amdgpu_bo_list {
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 024dfbd87f11..cee7d398916c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -51,7 +51,6 @@ static int amdgpu_cs_user_fence_chunk(struct amdgpu_cs_parser *p,
 	p->uf_entry.priority = 0;
 	p->uf_entry.tv.bo = &bo->tbo;
 	p->uf_entry.tv.shared = true;
-	p->uf_entry.user_pages = NULL;
 
 	drm_gem_object_put_unlocked(gobj);
 
@@ -531,24 +530,19 @@ static int amdgpu_cs_list_validate(struct amdgpu_cs_parser *p,
 
 	list_for_each_entry(lobj, validated, tv.head) {
 		struct amdgpu_bo *bo = ttm_to_amdgpu_bo(lobj->tv.bo);
-		bool binding_userptr = false;
 		struct mm_struct *usermm;
 
 		usermm = amdgpu_ttm_tt_get_usermm(bo->tbo.ttm);
 		if (usermm && usermm != current->mm)
 			return -EPERM;
 
-		/* Check if we have user pages and nobody bound the BO already */
-		if (amdgpu_ttm_tt_userptr_needs_pages(bo->tbo.ttm) &&
-		    lobj->user_pages) {
+		if (amdgpu_ttm_tt_is_userptr(bo->tbo.ttm) &&
+		    lobj->user_invalidated) {
 			amdgpu_bo_placement_from_domain(bo,
 							AMDGPU_GEM_DOMAIN_CPU);
 			r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
 			if (r)
 				return r;
-			amdgpu_ttm_tt_set_user_pages(bo->tbo.ttm,
-						     lobj->user_pages);
-			binding_userptr = true;
 		}
 
 		if (p->evictable == lobj)
@@ -557,11 +551,6 @@ static int amdgpu_cs_list_validate(struct amdgpu_cs_parser *p,
 		r = amdgpu_cs_validate(p, bo);
 		if (r)
 			return r;
-
-		if (binding_userptr) {
-			kvfree(lobj->user_pages);
-			lobj->user_pages = NULL;
-		}
 	}
 	return 0;
 }
@@ -576,7 +565,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 	struct amdgpu_bo *gds;
 	struct amdgpu_bo *gws;
 	struct amdgpu_bo *oa;
-	unsigned tries = 10;
+	struct list_head userpage_list;
 	int r;
 
 	INIT_LIST_HEAD(&p->validated);
@@ -585,7 +574,6 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 	if (cs->in.bo_list_handle) {
 		if (p->bo_list)
 			return -EINVAL;
-
 		r = amdgpu_bo_list_get(fpriv, cs->in.bo_list_handle,
 				       &p->bo_list);
 		if (r)
@@ -600,7 +588,8 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 
 	amdgpu_bo_list_get_list(p->bo_list, &p->validated);
 	if (p->bo_list->first_userptr != p->bo_list->num_entries)
-		p->mn = amdgpu_mn_get(p->adev, AMDGPU_MN_TYPE_GFX);
+		p->mn = amdgpu_mn_get(current->mm, p->adev,
+					AMDGPU_MN_TYPE_GFX);
 
 	INIT_LIST_HEAD(&duplicates);
 	amdgpu_vm_get_pd_bo(&fpriv->vm, &p->validated, &p->vm_pd);
@@ -608,79 +597,72 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 	if (p->uf_entry.tv.bo && !ttm_to_amdgpu_bo(p->uf_entry.tv.bo)->parent)
 		list_add(&p->uf_entry.tv.head, &p->validated);
 
-	while (1) {
-		struct list_head need_pages;
+	r = ttm_eu_reserve_buffers(&p->ticket, &p->validated, true,
+				   &duplicates);
+	if (unlikely(r != 0)) {
+		if (r != -ERESTARTSYS)
+			DRM_ERROR("ttm_eu_reserve_buffers failed.\n");
+		goto out;
+	}
 
-		r = ttm_eu_reserve_buffers(&p->ticket, &p->validated, true,
-					   &duplicates);
-		if (unlikely(r != 0)) {
-			if (r != -ERESTARTSYS)
-				DRM_ERROR("ttm_eu_reserve_buffers failed.\n");
-			goto error_free_pages;
-		}
+	INIT_LIST_HEAD(&userpage_list);
+	amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
+		struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);
 
-		INIT_LIST_HEAD(&need_pages);
-		amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
-			struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);
+		list_del(&e->tv.head);
+		list_add(&e->tv.head, &userpage_list);
+		amdgpu_bo_unreserve(bo);
+	}
 
-			if (amdgpu_ttm_tt_userptr_invalidated(bo->tbo.ttm,
-				 &e->user_invalidated) && e->user_pages) {
+	/* Get userptr backing pages. If pages are updated after registered
+	 * in amdgpu_gem_userptr_ioctl(), amdgpu_cs_list_validate() will do
+	 * amdgpu_ttm_backend_bind() to flush and invalidate new pages
+	 */
+	if (!list_empty(&userpage_list)) {
+		/* Unreserve everything again, to avoid circular locking case
+		 * bo::reserve -> mmap->sem
+		 */
+		ttm_eu_backoff_reservation(&p->ticket, &p->validated);
 
-				/* We acquired a page array, but somebody
-				 * invalidated it. Free it and try again
-				 */
-				release_pages(e->user_pages,
-					      bo->tbo.ttm->num_pages);
-				kvfree(e->user_pages);
-				e->user_pages = NULL;
+		list_for_each_entry(e, &userpage_list, tv.head) {
+			struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);
+			bool userpage_invalidated = false;
+			struct page **pages;
+			int i;
+
+			pages = kvmalloc_array(bo->tbo.ttm->num_pages,
+						sizeof(*pages),
+						GFP_KERNEL | __GFP_ZERO);
+			if (!pages) {
+				DRM_ERROR("calloc failure\n");
+				return -ENOMEM;
 			}
 
-			if (amdgpu_ttm_tt_userptr_needs_pages(bo->tbo.ttm) &&
-			    !e->user_pages) {
-				list_del(&e->tv.head);
-				list_add(&e->tv.head, &need_pages);
-
-				amdgpu_bo_unreserve(bo);
+			r = amdgpu_ttm_tt_get_user_pages(bo->tbo.ttm, pages);
+			if (r) {
+				kvfree(pages);
+				return r;
 			}
-		}
 
-		if (list_empty(&need_pages))
-			break;
-
-		/* Unreserve everything again. */
-		ttm_eu_backoff_reservation(&p->ticket, &p->validated);
-
-		/* We tried too many times, just abort */
-		if (!--tries) {
-			r = -EDEADLK;
-			DRM_ERROR("deadlock in %s\n", __func__);
-			goto error_free_pages;
+			for (i = 0; i < bo->tbo.ttm->num_pages; i++) {
+				if (bo->tbo.ttm->pages[i] != pages[i]) {
+					bo->tbo.ttm->pages[i] = pages[i];
+					userpage_invalidated = true;
+				}
+			}
+			e->user_invalidated = userpage_invalidated;
+			kvfree(pages);
 		}
 
-		/* Fill the page arrays for all userptrs. */
-		list_for_each_entry(e, &need_pages, tv.head) {
-			struct ttm_tt *ttm = e->tv.bo->ttm;
-
-			e->user_pages = kvmalloc_array(ttm->num_pages,
-							 sizeof(struct page*),
-							 GFP_KERNEL | __GFP_ZERO);
-			if (!e->user_pages) {
-				r = -ENOMEM;
-				DRM_ERROR("calloc failure in %s\n", __func__);
-				goto error_free_pages;
-			}
+		list_splice(&userpage_list, &p->validated);
 
-			r = amdgpu_ttm_tt_get_user_pages(ttm, e->user_pages);
-			if (r) {
-				DRM_ERROR("amdgpu_ttm_tt_get_user_pages failed.\n");
-				kvfree(e->user_pages);
-				e->user_pages = NULL;
-				goto error_free_pages;
-			}
+		r = ttm_eu_reserve_buffers(&p->ticket, &p->validated, true,
+					   &duplicates);
+		if (unlikely(r != 0)) {
+			if (r != -ERESTARTSYS)
+				DRM_ERROR("ttm_eu_reserve_buffers failed.\n");
+			goto out;
 		}
-
-		/* And try again. */
-		list_splice(&need_pages, &p->validated);
 	}
 
 	amdgpu_cs_get_threshold_for_moves(p->adev, &p->bytes_moved_threshold,
@@ -743,17 +725,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 error_validate:
 	if (r)
 		ttm_eu_backoff_reservation(&p->ticket, &p->validated);
-
-error_free_pages:
-
-	amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
-		if (!e->user_pages)
-			continue;
-
-		release_pages(e->user_pages, e->tv.bo->ttm->num_pages);
-		kvfree(e->user_pages);
-	}
-
+out:
 	return r;
 }
 
@@ -1206,8 +1178,7 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
 	struct amdgpu_bo_list_entry *e;
 	struct amdgpu_job *job;
 	uint64_t seq;
-
-	int r;
+	int r = 0;
 
 	job = p->job;
 	p->job = NULL;
@@ -1216,15 +1187,21 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
 	if (r)
 		goto error_unlock;
 
-	/* No memory allocation is allowed while holding the mn lock */
+	/* No memory allocation is allowed while holding the mn lock.
+	 * p->mn is hold until amdgpu_cs_submit is finished and fence is added
+	 * to BOs.
+	 */
 	amdgpu_mn_lock(p->mn);
+
+	/* If userptr are updated after amdgpu_cs_parser_bos(), restart cs */
 	amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
 		struct amdgpu_bo *bo = ttm_to_amdgpu_bo(e->tv.bo);
 
-		if (amdgpu_ttm_tt_userptr_needs_pages(bo->tbo.ttm)) {
-			r = -ERESTARTSYS;
-			goto error_abort;
-		}
+		r |= amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
+	}
+	if (r) {
+		r = -ERESTARTSYS;
+		goto error_abort;
 	}
 
 	job->owner = p->filp;
@@ -1271,14 +1248,20 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
 int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 {
 	struct amdgpu_device *adev = dev->dev_private;
-	union drm_amdgpu_cs *cs = data;
-	struct amdgpu_cs_parser parser = {};
-	bool reserved_buffers = false;
+	union drm_amdgpu_cs *cs;
+	struct amdgpu_cs_parser parser;
+	bool reserved_buffers;
+	int tries = 10;
 	int i, r;
 
 	if (!adev->accel_working)
 		return -EBUSY;
 
+restart:
+	memset(&parser, 0, sizeof(parser));
+	cs = data;
+	reserved_buffers = false;
+
 	parser.adev = adev;
 	parser.filp = filp;
 
@@ -1320,6 +1303,15 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 
 out:
 	amdgpu_cs_parser_fini(&parser, r, reserved_buffers);
+
+	if (r == -ERESTARTSYS) {
+		if (!--tries) {
+			DRM_ERROR("Possible deadlock? Retry too many times\n");
+			return -EDEADLK;
+		}
+		goto restart;
+	}
+
 	return r;
 }
 
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
index 7b3d1ebda9df..ff9a8fdab20f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
@@ -336,26 +336,24 @@ int amdgpu_gem_userptr_ioctl(struct drm_device *dev, void *data,
 
 		r = amdgpu_bo_reserve(bo, true);
 		if (r)
-			goto free_pages;
+			goto user_pages_done;
 
 		amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
 		r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
 		amdgpu_bo_unreserve(bo);
 		if (r)
-			goto free_pages;
+			goto user_pages_done;
 	}
 
 	r = drm_gem_handle_create(filp, gobj, &handle);
-	/* drop reference from allocate - handle holds it now */
-	drm_gem_object_put_unlocked(gobj);
 	if (r)
-		return r;
+		goto user_pages_done;
 
 	args->handle = handle;
-	return 0;
 
-free_pages:
-	release_pages(bo->tbo.ttm->pages, bo->tbo.ttm->num_pages);
+user_pages_done:
+	if (args->flags & AMDGPU_GEM_USERPTR_VALIDATE)
+		amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm);
 
 release_object:
 	drm_gem_object_put_unlocked(gobj);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
index 56595b3d90d2..6b6becdb725b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c
@@ -229,8 +229,6 @@ static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
 			true, false, MAX_SCHEDULE_TIMEOUT);
 		if (r <= 0)
 			DRM_ERROR("(%ld) failed to wait for user bo\n", r);
-
-		amdgpu_ttm_tt_mark_user_pages(bo->tbo.ttm);
 	}
 }
 
@@ -355,15 +353,16 @@ static struct hmm_mirror_ops amdgpu_hmm_mirror_ops[] = {
 /**
  * amdgpu_mn_get - create HMM mirror context
  *
+ * @mm: the mm struct
  * @adev: amdgpu device pointer
  * @type: type of MMU notifier context
  *
- * Creates a HMM mirror context for current->mm.
+ * Creates a HMM mirror context for mm.
  */
-struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
+struct amdgpu_mn *amdgpu_mn_get(struct mm_struct *mm,
+				struct amdgpu_device *adev,
 				enum amdgpu_mn_type type)
 {
-	struct mm_struct *mm = current->mm;
 	struct amdgpu_mn *amn;
 	unsigned long key = AMDGPU_MN_KEY(mm, type);
 	int r;
@@ -433,7 +432,7 @@ int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
 	struct list_head bos;
 	struct interval_tree_node *it;
 
-	amn = amdgpu_mn_get(adev, type);
+	amn = amdgpu_mn_get(current->mm, adev, type);
 	if (IS_ERR(amn))
 		return PTR_ERR(amn);
 
@@ -515,3 +514,26 @@ void amdgpu_mn_unregister(struct amdgpu_bo *bo)
 	mutex_unlock(&adev->mn_lock);
 }
 
+/* flags used by HMM internal, not related to CPU/GPU PTE flags */
+static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = {
+		(1 << 0), /* HMM_PFN_VALID */
+		(1 << 1), /* HMM_PFN_WRITE */
+		0 /* HMM_PFN_DEVICE_PRIVATE */
+};
+
+static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = {
+		0xfffffffffffffffeUL, /* HMM_PFN_ERROR */
+		0, /* HMM_PFN_NONE */
+		0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */
+};
+
+void amdgpu_hmm_init_range(struct hmm_range *range)
+{
+	if (range) {
+		range->flags = hmm_range_flags;
+		range->values = hmm_range_values;
+		range->pfn_shift = PAGE_SHIFT;
+		range->pfns = NULL;
+		INIT_LIST_HEAD(&range->list);
+	}
+}
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
index 0e2752646e6f..59ea30e149bd 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h
@@ -25,9 +25,10 @@
 #define __AMDGPU_MN_H__
 
 /*
- * MMU Notifier
+ * HMM mirror
  */
 struct amdgpu_mn;
+struct hmm_range;
 
 enum amdgpu_mn_type {
 	AMDGPU_MN_TYPE_GFX,
@@ -37,10 +38,12 @@ enum amdgpu_mn_type {
 #if defined(CONFIG_HMM)
 void amdgpu_mn_lock(struct amdgpu_mn *mn);
 void amdgpu_mn_unlock(struct amdgpu_mn *mn);
-struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev,
+struct amdgpu_mn *amdgpu_mn_get(struct mm_struct *mm,
+				struct amdgpu_device *adev,
 				enum amdgpu_mn_type type);
 int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr);
 void amdgpu_mn_unregister(struct amdgpu_bo *bo);
+void amdgpu_hmm_init_range(struct hmm_range *range);
 #else
 static inline void amdgpu_mn_lock(struct amdgpu_mn *mn) {}
 static inline void amdgpu_mn_unlock(struct amdgpu_mn *mn) {}
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index c91ec3101d00..4a1cb4d15dfb 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -43,6 +43,7 @@
 #include <linux/pagemap.h>
 #include <linux/debugfs.h>
 #include <linux/iommu.h>
+#include <linux/hmm.h>
 #include "amdgpu.h"
 #include "amdgpu_object.h"
 #include "amdgpu_trace.h"
@@ -705,11 +706,6 @@ static unsigned long amdgpu_ttm_io_mem_pfn(struct ttm_buffer_object *bo,
 /*
  * TTM backend functions.
  */
-struct amdgpu_ttm_gup_task_list {
-	struct list_head	list;
-	struct task_struct	*task;
-};
-
 struct amdgpu_ttm_tt {
 	struct ttm_dma_tt	ttm;
 	u64			offset;
@@ -718,85 +714,91 @@ struct amdgpu_ttm_tt {
 	uint32_t		userflags;
 	spinlock_t              guptasklock;
 	struct list_head        guptasks;
-	atomic_t		mmu_invalidations;
-	uint32_t		last_set_pages;
+	struct hmm_range	range;
 };
 
 /**
- * amdgpu_ttm_tt_get_user_pages - Pin pages of memory pointed to by a USERPTR
- * pointer to memory
+ * amdgpu_ttm_tt_get_user_pages - get device accessible pages that back user
+ * memory and start HMM tracking CPU page table update
  *
- * Called by amdgpu_gem_userptr_ioctl() and amdgpu_cs_parser_bos().
- * This provides a wrapper around the get_user_pages() call to provide
- * device accessible pages that back user memory.
+ * Calling function must call amdgpu_ttm_tt_userptr_range_done() once and only
+ * once afterwards to stop HMM tracking
  */
 int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages)
 {
 	struct amdgpu_ttm_tt *gtt = (void *)ttm;
 	struct mm_struct *mm = gtt->usertask->mm;
-	unsigned int flags = 0;
-	unsigned pinned = 0;
-	int r;
+	unsigned long end = gtt->userptr + ttm->num_pages * PAGE_SIZE;
+	struct hmm_range *range = &gtt->range;
+	int r, i;
 
 	if (!mm) /* Happens during process shutdown */
 		return -ESRCH;
 
-	if (!(gtt->userflags & AMDGPU_GEM_USERPTR_READONLY))
-		flags |= FOLL_WRITE;
+	amdgpu_hmm_init_range(range);
 
 	down_read(&mm->mmap_sem);
 
-	if (gtt->userflags & AMDGPU_GEM_USERPTR_ANONONLY) {
-		/*
-		 * check that we only use anonymous memory to prevent problems
-		 * with writeback
-		 */
-		unsigned long end = gtt->userptr + ttm->num_pages * PAGE_SIZE;
-		struct vm_area_struct *vma;
+	range->vma = find_vma(mm, gtt->userptr);
+	if (!range->vma || range->vma->vm_file || range->vma->vm_end < end) {
+		r = -EPERM;
+		goto out;
+	}
+	range->pfns = kvmalloc_array(ttm->num_pages, sizeof(uint64_t),
+				GFP_KERNEL | __GFP_ZERO);
+	if (range->pfns == NULL) {
+		r = -ENOMEM;
+		goto out;
+	}
+	range->start = gtt->userptr;
+	range->end = end;
 
-		vma = find_vma(mm, gtt->userptr);
-		if (!vma || vma->vm_file || vma->vm_end < end) {
-			up_read(&mm->mmap_sem);
-			return -EPERM;
-		}
+	for (i = 0; i < ttm->num_pages; i++) {
+		range->pfns[i] = range->flags[HMM_PFN_VALID];
+		range->pfns[i] |= amdgpu_ttm_tt_is_readonly(ttm) ?
+					0 : range->flags[HMM_PFN_WRITE];
 	}
 
-	/* loop enough times using contiguous pages of memory */
-	do {
-		unsigned num_pages = ttm->num_pages - pinned;
-		uint64_t userptr = gtt->userptr + pinned * PAGE_SIZE;
-		struct page **p = pages + pinned;
-		struct amdgpu_ttm_gup_task_list guptask;
+	/* This may triggles page table update */
+	r = hmm_vma_fault(range, true);
+	if (r)
+		goto out_free_pfns;
 
-		guptask.task = current;
-		spin_lock(&gtt->guptasklock);
-		list_add(&guptask.list, &gtt->guptasks);
-		spin_unlock(&gtt->guptasklock);
+	for (i = 0; i < ttm->num_pages; i++)
+		pages[i] = hmm_pfn_to_page(range, range->pfns[i]);
 
-		if (mm == current->mm)
-			r = get_user_pages(userptr, num_pages, flags, p, NULL);
-		else
-			r = get_user_pages_remote(gtt->usertask,
-					mm, userptr, num_pages,
-					flags, p, NULL, NULL);
+	up_read(&mm->mmap_sem);
+	return 0;
 
-		spin_lock(&gtt->guptasklock);
-		list_del(&guptask.list);
-		spin_unlock(&gtt->guptasklock);
+out_free_pfns:
+	kvfree(range->pfns);
+	range->pfns = NULL;
+out:
+	up_read(&mm->mmap_sem);
+	return r;
+}
 
-		if (r < 0)
-			goto release_pages;
+/**
+ * amdgpu_ttm_tt_userptr_range_done - stop HMM track the CPU page table change
+ * Check if the pages backing this ttm range have been invalidated
+ *
+ * Returns: true if pages are invalidated since the last time they've been set
+ */
+bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm)
+{
+	struct amdgpu_ttm_tt *gtt = (void *)ttm;
+	int r;
 
-		pinned += r;
+	if (gtt == NULL || !gtt->userptr)
+		return false;
 
-	} while (pinned < ttm->num_pages);
+	r = !hmm_vma_range_done(&gtt->range);
 
-	up_read(&mm->mmap_sem);
-	return 0;
+	if (gtt->range.pfns) {
+		kvfree(gtt->range.pfns);
+		gtt->range.pfns = NULL;
+	}
 
-release_pages:
-	release_pages(pages, pinned);
-	up_read(&mm->mmap_sem);
 	return r;
 }
 
@@ -809,16 +811,10 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages)
  */
 void amdgpu_ttm_tt_set_user_pages(struct ttm_tt *ttm, struct page **pages)
 {
-	struct amdgpu_ttm_tt *gtt = (void *)ttm;
 	unsigned i;
 
-	gtt->last_set_pages = atomic_read(&gtt->mmu_invalidations);
-	for (i = 0; i < ttm->num_pages; ++i) {
-		if (ttm->pages[i])
-			put_page(ttm->pages[i]);
-
+	for (i = 0; i < ttm->num_pages; ++i)
 		ttm->pages[i] = pages ? pages[i] : NULL;
-	}
 }
 
 /**
@@ -903,9 +899,6 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm)
 	/* unmap the pages mapped to the device */
 	dma_unmap_sg(adev->dev, ttm->sg->sgl, ttm->sg->nents, direction);
 
-	/* mark the pages as dirty */
-	amdgpu_ttm_tt_mark_user_pages(ttm);
-
 	sg_free_table(ttm->sg);
 }
 
@@ -1258,8 +1251,6 @@ int amdgpu_ttm_tt_set_userptr(struct ttm_tt *ttm, uint64_t addr,
 
 	spin_lock_init(&gtt->guptasklock);
 	INIT_LIST_HEAD(&gtt->guptasks);
-	atomic_set(&gtt->mmu_invalidations, 0);
-	gtt->last_set_pages = 0;
 
 	return 0;
 }
@@ -1289,7 +1280,6 @@ bool amdgpu_ttm_tt_affect_userptr(struct ttm_tt *ttm, unsigned long start,
 				  unsigned long end)
 {
 	struct amdgpu_ttm_tt *gtt = (void *)ttm;
-	struct amdgpu_ttm_gup_task_list *entry;
 	unsigned long size;
 
 	if (gtt == NULL || !gtt->userptr)
@@ -1302,48 +1292,20 @@ bool amdgpu_ttm_tt_affect_userptr(struct ttm_tt *ttm, unsigned long start,
 	if (gtt->userptr > end || gtt->userptr + size <= start)
 		return false;
 
-	/* Search the lists of tasks that hold this mapping and see
-	 * if current is one of them.  If it is return false.
-	 */
-	spin_lock(&gtt->guptasklock);
-	list_for_each_entry(entry, &gtt->guptasks, list) {
-		if (entry->task == current) {
-			spin_unlock(&gtt->guptasklock);
-			return false;
-		}
-	}
-	spin_unlock(&gtt->guptasklock);
-
-	atomic_inc(&gtt->mmu_invalidations);
-
 	return true;
 }
 
 /**
- * amdgpu_ttm_tt_userptr_invalidated - Has the ttm_tt object been invalidated?
+ * amdgpu_ttm_tt_is_userptr - Have the pages backing by userptr?
  */
-bool amdgpu_ttm_tt_userptr_invalidated(struct ttm_tt *ttm,
-				       int *last_invalidated)
-{
-	struct amdgpu_ttm_tt *gtt = (void *)ttm;
-	int prev_invalidated = *last_invalidated;
-
-	*last_invalidated = atomic_read(&gtt->mmu_invalidations);
-	return prev_invalidated != *last_invalidated;
-}
-
-/**
- * amdgpu_ttm_tt_userptr_needs_pages - Have the pages backing this ttm_tt object
- * been invalidated since the last time they've been set?
- */
-bool amdgpu_ttm_tt_userptr_needs_pages(struct ttm_tt *ttm)
+bool amdgpu_ttm_tt_is_userptr(struct ttm_tt *ttm)
 {
 	struct amdgpu_ttm_tt *gtt = (void *)ttm;
 
 	if (gtt == NULL || !gtt->userptr)
 		return false;
 
-	return atomic_read(&gtt->mmu_invalidations) != gtt->last_set_pages;
+	return true;
 }
 
 /**
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
index b5b2d101f7db..8988c87fff9d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
@@ -102,6 +102,7 @@ int amdgpu_ttm_alloc_gart(struct ttm_buffer_object *bo);
 int amdgpu_ttm_recover_gart(struct ttm_buffer_object *tbo);
 
 int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages);
+bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm);
 void amdgpu_ttm_tt_set_user_pages(struct ttm_tt *ttm, struct page **pages);
 void amdgpu_ttm_tt_mark_user_pages(struct ttm_tt *ttm);
 int amdgpu_ttm_tt_set_userptr(struct ttm_tt *ttm, uint64_t addr,
@@ -112,7 +113,7 @@ bool amdgpu_ttm_tt_affect_userptr(struct ttm_tt *ttm, unsigned long start,
 				  unsigned long end);
 bool amdgpu_ttm_tt_userptr_invalidated(struct ttm_tt *ttm,
 				       int *last_invalidated);
-bool amdgpu_ttm_tt_userptr_needs_pages(struct ttm_tt *ttm);
+bool amdgpu_ttm_tt_is_userptr(struct ttm_tt *ttm);
 bool amdgpu_ttm_tt_is_readonly(struct ttm_tt *ttm);
 uint64_t amdgpu_ttm_tt_pde_flags(struct ttm_tt *ttm, struct ttm_mem_reg *mem);
 uint64_t amdgpu_ttm_tt_pte_flags(struct amdgpu_device *adev, struct ttm_tt *ttm,
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 2acb9838913e..4a67a88acea1 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -618,7 +618,6 @@ void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
 	entry->priority = 0;
 	entry->tv.bo = &vm->root.base.bo->tbo;
 	entry->tv.shared = true;
-	entry->user_pages = NULL;
 	list_add(&entry->tv.head, validated);
 }
 
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
index 8372556b52eb..fe120cc0930c 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
@@ -1158,6 +1158,33 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
 
 	retval = 0;
 
+	/* Do init_mqd before dqm_lock(dqm) to avoid circular locking order:
+	 * lock(dqm) -> bo::reserve
+	 */
+	mqd_mgr = dqm->ops.get_mqd_manager(dqm,
+			get_mqd_type_from_queue_type(q->properties.type));
+
+	if (!mqd_mgr) {
+		retval = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * Eviction state logic: we only mark active queues as evicted
+	 * to avoid the overhead of restoring inactive queues later
+	 */
+	if (qpd->evicted)
+		q->properties.is_evicted = (q->properties.queue_size > 0 &&
+					    q->properties.queue_percent > 0 &&
+					    q->properties.queue_address != 0);
+	dqm->asic_ops.init_sdma_vm(dqm, q, qpd);
+	q->properties.tba_addr = qpd->tba_addr;
+	q->properties.tma_addr = qpd->tma_addr;
+	retval = mqd_mgr->init_mqd(mqd_mgr, &q->mqd, &q->mqd_mem_obj,
+				&q->gart_mqd_addr, &q->properties);
+	if (retval)
+		goto out;
+
 	dqm_lock(dqm);
 
 	if (dqm->total_queue_count >= max_num_of_queues_per_device) {
@@ -1181,30 +1208,6 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
 	if (retval)
 		goto out_deallocate_sdma_queue;
 
-	mqd_mgr = dqm->ops.get_mqd_manager(dqm,
-			get_mqd_type_from_queue_type(q->properties.type));
-
-	if (!mqd_mgr) {
-		retval = -ENOMEM;
-		goto out_deallocate_doorbell;
-	}
-	/*
-	 * Eviction state logic: we only mark active queues as evicted
-	 * to avoid the overhead of restoring inactive queues later
-	 */
-	if (qpd->evicted)
-		q->properties.is_evicted = (q->properties.queue_size > 0 &&
-					    q->properties.queue_percent > 0 &&
-					    q->properties.queue_address != 0);
-
-	dqm->asic_ops.init_sdma_vm(dqm, q, qpd);
-
-	q->properties.tba_addr = qpd->tba_addr;
-	q->properties.tma_addr = qpd->tma_addr;
-	retval = mqd_mgr->init_mqd(mqd_mgr, &q->mqd, &q->mqd_mem_obj,
-				&q->gart_mqd_addr, &q->properties);
-	if (retval)
-		goto out_deallocate_doorbell;
 
 	list_add(&q->list, &qpd->queues_list);
 	qpd->queue_count++;
@@ -1228,14 +1231,12 @@ static int create_queue_cpsch(struct device_queue_manager *dqm, struct queue *q,
 	dqm_unlock(dqm);
 	return retval;
 
-out_deallocate_doorbell:
-	deallocate_doorbell(qpd, q);
 out_deallocate_sdma_queue:
 	if (q->properties.type == KFD_QUEUE_TYPE_SDMA)
 		deallocate_sdma_queue(dqm, q->sdma_id);
 out_unlock:
 	dqm_unlock(dqm);
-
+out:
 	return retval;
 }
 
@@ -1398,8 +1399,6 @@ static int destroy_queue_cpsch(struct device_queue_manager *dqm,
 			qpd->reset_wavefronts = true;
 	}
 
-	mqd_mgr->uninit_mqd(mqd_mgr, q->mqd, q->mqd_mem_obj);
-
 	/*
 	 * Unconditionally decrement this counter, regardless of the queue's
 	 * type
@@ -1410,6 +1409,9 @@ static int destroy_queue_cpsch(struct device_queue_manager *dqm,
 
 	dqm_unlock(dqm);
 
+	/* Do uninit_mqd after dqm_unlock(dqm) to avoid circular locking */
+	mqd_mgr->uninit_mqd(mqd_mgr, q->mqd, q->mqd_mem_obj);
+
 	return retval;
 
 failed:
@@ -1631,7 +1633,11 @@ static int process_termination_cpsch(struct device_queue_manager *dqm,
 		qpd->reset_wavefronts = false;
 	}
 
-	/* lastly, free mqd resources */
+	dqm_unlock(dqm);
+
+	/* Lastly, free mqd resources.
+	 * Do uninit_mqd() after dqm_unlock to avoid circular locking.
+	 */
 	list_for_each_entry_safe(q, next, &qpd->queues_list, list) {
 		mqd_mgr = dqm->ops.get_mqd_manager(dqm,
 			get_mqd_type_from_queue_type(q->properties.type));
@@ -1645,7 +1651,6 @@ static int process_termination_cpsch(struct device_queue_manager *dqm,
 	}
 
 out:
-	dqm_unlock(dqm);
 	return retval;
 }
 
-- 
2.17.1



More information about the amd-gfx mailing list