Questions about how to force tokio to kill all threads to make it single threaded

[LeeTeng2001]

In a gist, I have a main function that

// this is necessary to force single thread for setns
#[tokio::main(flavor = "current_thread")]
async fn main() -> Result<()> {
   // run async task
   some_task.await

   // ?? operation to kill all os threads spawned in some_task

   // requires single thread
   libc::setns()
}

[LeeTeng2001]

I need a way to kill all threads spawned by some_task, the performance impact is acceptable in my case

[Darksonn]

You're using the current-thread runtime, so no threads are spawned by Tokio.