default or selected kernelversion does not have config value CONFIG_XEN_TMEM.
Result is shown for kernelversion 6.9.9
CONFIG_XEN_TMEM (not configurable)
modulename: tmem.ko
configname: CONFIG_XEN_TMEM
Linux Kernel Configuration
└─>Device Drivers
└─>Xen driver support
└─>XEN_TMEM
In linux kernel since version 3.1 (release Date: 2011-10-24)
Shim to interface in-kernel Transcendent Memory hooks
(e.g. cleancache and frontswap) to Xen tmem hypercalls.
(e.g. cleancache and frontswap) to Xen tmem hypercalls.