Update internode_ll.cu (#376)

csrc/kernels/internode_ll.cu

@@ -72,7 +72,7 @@ dispatch(void* packed_recv_x, void* packed_recv_x_scales,
     const size_t hidden_bytes = kHidden * (kUseFP8 ? sizeof(__nv_fp8_storage_t) : sizeof(nv_bfloat16));
     const size_t hidden_int4 = hidden_bytes / sizeof(int4);
 
-    // Message package: hidden data, FP8 scales, index at source
+    // Message package: index at source (int), 3 reserved int fields, hidden data, FP8 scales
     // NOTES: currently we have 3 reserved int fields for future use
     using vec_t = std::conditional_t<kUseFP8, int2, int4>;
     const size_t num_bytes_per_msg = sizeof(int4) + (kUseFP8 ? (kHidden + num_scales * sizeof(float)) : (kHidden * sizeof(nv_bfloat16)));