Torch installed by pip was compiled with mkl or not

after pip install torch,i use
print(*torch.__config__.show().split("\n"), sep="\n") to check mkl, return somthing like this
“… BLAS=MKL…”
but, when use ldd libtorch.so, no mkl library was linked.
and i use perf top to view some pytorch scripte invoke, no mkl lib was invoked.
that’s weired, so i want to know whether torch(pip install) has mkl or not . if it does, how mkl is compiled into libtorch .