On 2018å¹´01æ??10æ?¥ 20:54, Christian König wrote:
> Free up a pasid after all fences signaled.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c | 73 +++++++++++++++++++++++++++++++++
> drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h | 2 +
> 2 files changed, 75 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
> index 5248a3232aff..63c9fb0361c0 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.c
> @@ -40,6 +40,12 @@
> */
> static DEFINE_IDA(amdgpu_pasid_ida);
>
> +/* Helper to free pasid from a fence callback */
> +struct amdgpu_pasid_cb {
> + struct dma_fence_cb cb;
> + unsigned int pasid;
> +};
> +
> /**
> * amdgpu_pasid_alloc - Allocate a PASID
> * @bits: Maximum width of the PASID in bits, must be at least 1
> @@ -75,6 +81,73 @@ void amdgpu_pasid_free(unsigned int pasid)
> ida_simple_remove(&amdgpu_pasid_ida, pasid);
> }
>
> +static void amdgpu_pasid_free_cb(struct dma_fence *fence,
> + struct dma_fence_cb *_cb)
> +{
> + struct amdgpu_pasid_cb *cb =
> + container_of(_cb, struct amdgpu_pasid_cb, cb);
> +
> + amdgpu_pasid_free(cb->pasid);
> + dma_fence_put(fence);
> + kfree(cb);
> +}
> +
> +/**
> + * amdgpu_pasid_free_delayed - free pasid when fences signal
> + *
> + * @resv: reservation object with the fences to wait for
> + * @pasid: pasid to free
> + *
> + * Free the pasid only after all the fences in resv are signaled.
> + */
> +void amdgpu_pasid_free_delayed(struct reservation_object *resv,
> + unsigned int pasid)
> +{
> + struct dma_fence *fence, **fences;
> + struct amdgpu_pasid_cb *cb;
> + unsigned count;
> + int r;
> +
> + r = reservation_object_get_fences_rcu(resv, NULL, &count, &fences);
> + if (r) {
> + /* Not enough memory to grab the fence list, as last resort
> + * block for all the fences to complete.
> + */
> + reservation_object_wait_timeout_rcu(resv, true, false,
> + MAX_SCHEDULE_TIMEOUT);
> + amdgpu_pasid_free(pasid);
> + return;
> + }
> +
> + if (count == 0) {
> + amdgpu_pasid_free(pasid);
> + return;
> + }
> +
> + if (count == 1) {
> + fence = fences[0];
> + kfree(fences);
> + } else {
> + uint64_t context = dma_fence_context_alloc(1);
> +
> + fence = &dma_fence_array_create(count, fences, context,
> + 1, false)->base;
Here needs to check if fence is NULL.
Regards,
David Zhou
> + }
> +
> + cb = kmalloc(sizeof(*cb), GFP_KERNEL);
> + if (!cb) {
> + /* Last resort when we are OOM */
> + dma_fence_wait(fence, false);
> + dma_fence_put(fence);
> + amdgpu_pasid_free(pasid);
> + } else {
> + cb->pasid = pasid;
> + if (dma_fence_add_callback(fence, &cb->cb,
> + amdgpu_pasid_free_cb))
> + amdgpu_pasid_free_cb(fence, &cb->cb);
> + }
> +}
> +
> /*
> * VMID manager
> *
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
> index ad931fa570b3..38f37c16fc5e 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
> @@ -69,6 +69,8 @@ struct amdgpu_vmid_mgr {
>
> int amdgpu_pasid_alloc(unsigned int bits);
> void amdgpu_pasid_free(unsigned int pasid);
> +void amdgpu_pasid_free_delayed(struct reservation_object *resv,
> + unsigned int pasid);
>
> bool amdgpu_vmid_had_gpu_reset(struct amdgpu_device *adev,
> struct amdgpu_vmid *id);
