This method searches through the ThreadContexts stored in the system, and has no concrete connection to Process other than it happened to be used by a Process in the clone system call. By moving it, we can use its functionality in classes other than Process. Change-Id: Ic6899c335dc13841c6fe948ea3a4f8ad67e562bb Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24285 Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>