[Fix core lib warning] Fix using `torch.tensor` for tensor conversion (#5028)

python/dgl/backend/pytorch/tensor.py

@@ -341,7 +341,7 @@ def pack_padded_tensor(input, lengths):
 
 def boolean_mask(input, mask):
     if "bool" not in str(mask.dtype):
-        mask = th.tensor(mask, dtype=th.bool)
+        mask = th.as_tensor(mask, dtype=th.bool)
     return input[mask]
 
 

python/dgl/nn/pytorch/glob.py

@@ -729,8 +729,8 @@ class MultiHeadAttention(nn.Module):
         max_len_x = max(lengths_x)
         max_len_mem = max(lengths_mem)
         device = x.device
-        lengths_x = th.tensor(lengths_x, dtype=th.int64, device=device)
-        lengths_mem = th.tensor(lengths_mem, dtype=th.int64, device=device)
+        lengths_x = th.as_tensor(lengths_x, dtype=th.int64, device=device)
+        lengths_mem = th.as_tensor(lengths_mem, dtype=th.int64, device=device)
 
         queries = self.proj_q(x).view(-1, self.num_heads, self.d_head)
         keys = self.proj_k(mem).view(-1, self.num_heads, self.d_head)