Am 2022-09-14 um 12:08 schrieb Philip Yang:
Free page table BO from vm resv unlocked context generate below
warnings.
Add a pt_free_work in vm to free page table BO from vm->pt_freed list.
pass vm resv unlock status from page table update caller, and add vm_bo
entry to vm->pt_freed list and schedule the pt_free_work if calling with
vm resv unlocked.
WARNING: CPU: 12 PID: 3238 at
drivers/gpu/drm/ttm/ttm_bo.c:106 ttm_bo_set_bulk_move+0xa1/0xc0
Call Trace:
amdgpu_vm_pt_free+0x42/0xd0 [amdgpu]
amdgpu_vm_pt_free_dfs+0xb3/0xf0 [amdgpu]
amdgpu_vm_ptes_update+0x52d/0x850 [amdgpu]
amdgpu_vm_update_range+0x2a6/0x640 [amdgpu]
svm_range_unmap_from_gpus+0x110/0x300 [amdgpu]
svm_range_cpu_invalidate_pagetables+0x535/0x600 [amdgpu]
__mmu_notifier_invalidate_range_start+0x1cd/0x230
unmap_vmas+0x9d/0x140
unmap_region+0xa8/0x110
Signed-off-by: Philip Yang <Philip.Yang@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 5 +++
drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 6 ++++
drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c | 41 +++++++++++++++++++++--
3 files changed, 49 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 59cac347baa3..20cfc8c9635b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -2022,6 +2022,9 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm)
spin_lock_init(&vm->invalidated_lock);
INIT_LIST_HEAD(&vm->freed);
INIT_LIST_HEAD(&vm->done);
+ INIT_LIST_HEAD(&vm->pt_freed);
+ INIT_WORK(&vm->pt_free_work, amdgpu_vm_pt_free_work);
+ spin_lock_init(&vm->pt_free_lock);
/* create scheduler entities for page table updates */
r = drm_sched_entity_init(&vm->immediate, DRM_SCHED_PRIORITY_NORMAL,
@@ -2223,6 +2226,8 @@ void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
amdgpu_amdkfd_gpuvm_destroy_cb(adev, vm);
+ flush_work(&vm->pt_free_work);
+
root = amdgpu_bo_ref(vm->root.bo);
amdgpu_bo_reserve(root, true);
amdgpu_vm_set_pasid(adev, vm, 0);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index 9ecb7f663e19..b77fe838c327 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -276,6 +276,11 @@ struct amdgpu_vm {
/* BOs which are invalidated, has been updated in the PTs */
struct list_head done;
+ /* PT BOs scheduled to free and fill with zero if vm_resv is not hold */
+ struct list_head pt_freed;
+ struct work_struct pt_free_work;
+ spinlock_t pt_free_lock;
+
/* contains the page directory */
struct amdgpu_vm_bo_base root;
struct dma_fence *last_update;
@@ -471,6 +476,7 @@ int amdgpu_vm_pde_update(struct amdgpu_vm_update_params *params,
int amdgpu_vm_ptes_update(struct amdgpu_vm_update_params *params,
uint64_t start, uint64_t end,
uint64_t dst, uint64_t flags);
+void amdgpu_vm_pt_free_work(struct work_struct *work);
#if defined(CONFIG_DEBUG_FS)
void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
index 88de9f0d4728..c16579471f22 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
@@ -641,6 +641,27 @@ static void amdgpu_vm_pt_free(struct amdgpu_vm_bo_base *entry)
amdgpu_bo_unref(&entry->bo);
}
+void amdgpu_vm_pt_free_work(struct work_struct *work)
+{
+ struct amdgpu_vm_bo_base *entry, *next;
+ struct amdgpu_vm *vm;
+ LIST_HEAD(pt_freed);
+
+ vm = container_of(work, struct amdgpu_vm, pt_free_work);
+
+ spin_lock(&vm->pt_free_lock);
+ list_splice_init(&vm->pt_freed, &pt_freed);
+ spin_unlock(&vm->pt_free_lock);
+
+ // flush_work in amdgpu_vm_fini ensure vm->root.bo is valid
+ amdgpu_bo_reserve(vm->root.bo, true);
+
+ list_for_each_entry_safe(entry, next, &pt_freed, vm_status)
+ amdgpu_vm_pt_free(entry);
+
+ amdgpu_bo_unreserve(vm->root.bo);
+}
+
/**
* amdgpu_vm_pt_free_dfs - free PD/PT levels
*
@@ -652,11 +673,24 @@ static void amdgpu_vm_pt_free(struct amdgpu_vm_bo_base *entry)
*/
static void amdgpu_vm_pt_free_dfs(struct amdgpu_device *adev,
struct amdgpu_vm *vm,
- struct amdgpu_vm_pt_cursor *start)
+ struct amdgpu_vm_pt_cursor *start,
+ bool unlocked)
{
struct amdgpu_vm_pt_cursor cursor;
struct amdgpu_vm_bo_base *entry;
+ if (unlocked) {
+ spin_lock(&vm->pt_free_lock);
+ for_each_amdgpu_vm_pt_dfs_safe(adev, vm, start, cursor, entry)
+ list_move(&entry->vm_status, &vm->pt_freed);
+
+ if (start)
+ list_move(&start->entry->vm_status, &vm->pt_freed);
+ spin_unlock(&vm->pt_free_lock);
Question for Christian: list_move will take the entry off another
vm_status list (evicted, idle, invalidated, relocated). I don't think
this is safe without holding a reservation lock in most cases. Since the
point here is to maintain a list of PTs to be freed without locking a
reservation, is the vm_status really the right way to do this?
Regards,
Felix
+ schedule_work(&vm->pt_free_work);
+ return;
+ }
+
for_each_amdgpu_vm_pt_dfs_safe(adev, vm, start, cursor, entry)
amdgpu_vm_pt_free(entry);
@@ -673,7 +707,7 @@ static void amdgpu_vm_pt_free_dfs(struct amdgpu_device *adev,
*/
void amdgpu_vm_pt_free_root(struct amdgpu_device *adev, struct amdgpu_vm *vm)
{
- amdgpu_vm_pt_free_dfs(adev, vm, NULL);
+ amdgpu_vm_pt_free_dfs(adev, vm, NULL, false);
}
/**
@@ -966,7 +1000,8 @@ int amdgpu_vm_ptes_update(struct amdgpu_vm_update_params *params,
if (cursor.entry->bo) {
params->table_freed = true;
amdgpu_vm_pt_free_dfs(adev, params->vm,
- &cursor);
+ &cursor,
+ params->unlocked);
}
amdgpu_vm_pt_next(adev, &cursor);
}
