Man pages matching name probe::vm.kmem_cache_free in section 3stap:

probe::vm.kmem_cache_free.3stap.en	debian 10 / systemtap-doc
probe::vm.kmem_cache_free.3stap.en	debian 11 / systemtap-doc
probe::vm.kmem_cache_free.3stap.en	debian 12 / systemtap-doc