On 2023-06-01 15:31, Philip Yang wrote:
Add pt_fence to amdgpu vm structure and implement helper functions. This fence will be shared by all page table BOs of the same amdgpu vm.Suggested-by: Felix Kuehling <felix.kuehl...@amd.com> Signed-off-by: Philip Yang <philip.y...@amd.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 2 + drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c | 45 +++++++++++++++++++++++ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 4 ++ drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h | 1 + 4 files changed, 52 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index 5af954abd5ba..09c116dfda31 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -1499,6 +1499,8 @@ int amdgpu_device_set_cg_state(struct amdgpu_device *adev, int amdgpu_device_set_pg_state(struct amdgpu_device *adev, enum amd_powergating_state state);+struct dma_fence *amdgpu_pt_fence_create(void);+ static inline bool amdgpu_device_has_timeouts_enabled(struct amdgpu_device *adev) { return amdgpu_gpu_recovery != 0 && diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c index c694b41f6461..d9bfb0af3a09 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fence.c @@ -57,6 +57,16 @@ struct amdgpu_fence { ktime_t start_timestamp; };+/*+ * Page table BO fence + * Fence used to ensure page table BOs are freed after TLB is flushed, to avoid + * H/W access corrupted data if the freed BO page is reused. + */ +struct amdgpu_pt_fence { + struct dma_fence base; + spinlock_t lock; +}; + static struct kmem_cache *amdgpu_fence_slab;int amdgpu_fence_slab_init(void)@@ -79,6 +89,7 @@ void amdgpu_fence_slab_fini(void) */ static const struct dma_fence_ops amdgpu_fence_ops; static const struct dma_fence_ops amdgpu_job_fence_ops; +static const struct dma_fence_ops amdgpu_pt_fence_ops; static inline struct amdgpu_fence *to_amdgpu_fence(struct dma_fence *f) { struct amdgpu_fence *__f = container_of(f, struct amdgpu_fence, base); @@ -852,6 +863,40 @@ static const struct dma_fence_ops amdgpu_job_fence_ops = { .release = amdgpu_job_fence_release, };+static atomic_t pt_fence_seq = ATOMIC_INIT(0);+ +struct dma_fence *amdgpu_pt_fence_create(void) +{ + struct amdgpu_pt_fence *fence; + + fence = kzalloc(sizeof(*fence), GFP_KERNEL); + if (!fence) + return NULL; + + spin_lock_init(&fence->lock); + dma_fence_init(&fence->base, &amdgpu_pt_fence_ops, &fence->lock, + dma_fence_context_alloc(1), atomic_inc_return(&pt_fence_seq));
Creating a new fence context per fence is probably wrong. I think we only need one PT fence context per GPU or per spatial partition, or maybe per VM.
Regards, Felix
+ + dma_fence_get(&fence->base); + return &fence->base; +} + +static const char *amdgpu_pt_fence_get_timeline_name(struct dma_fence *f) +{ + return "pt_fence_timeline"; +} + +static void amdgpu_pt_fence_release(struct dma_fence *f) +{ + kfree_rcu(f, rcu); +} + +static const struct dma_fence_ops amdgpu_pt_fence_ops = { + .get_driver_name = amdgpu_fence_get_driver_name, + .get_timeline_name = amdgpu_pt_fence_get_timeline_name, + .release = amdgpu_pt_fence_release, +}; + /* * Fence debugfs */ diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c index 37b9d8a8dbec..0219398e625c 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -2147,6 +2147,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm) vm->update_funcs = &amdgpu_vm_sdma_funcs;vm->last_update = dma_fence_get_stub();+ vm->pt_fence = amdgpu_pt_fence_create(); vm->last_unlocked = dma_fence_get_stub(); vm->last_tlb_flush = dma_fence_get_stub(); vm->generation = 0; @@ -2270,6 +2271,8 @@ int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm)dma_fence_put(vm->last_update);vm->last_update = dma_fence_get_stub(); + dma_fence_put(vm->pt_fence); + vm->pt_fence = amdgpu_pt_fence_create(); vm->is_compute_context = true;/* Free the shadow bo for compute VM */@@ -2358,6 +2361,7 @@ void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm) }dma_fence_put(vm->last_update);+ dma_fence_put(vm->pt_fence); for (i = 0; i < AMDGPU_MAX_VMHUBS; i++) amdgpu_vmid_free_reserved(adev, vm, i); } diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h index d551fca1780e..9cc729358612 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h @@ -286,6 +286,7 @@ struct amdgpu_vm { /* contains the page directory */ struct amdgpu_vm_bo_base root; struct dma_fence *last_update; + struct dma_fence *pt_fence;/* Scheduler entities for page table updates */struct drm_sched_entity immediate;
