CONFIG_RING_BUFFER (not configurable)

modulename: ring_buffer.ko

configname: CONFIG_RING_BUFFER

Linux Kernel Configuration
└─>Kernel hacking
└─>RING_BUFFER
In linux kernel since version 2.6.28 (release Date: 2008-12-24)  
source code:
kernel/trace/ring_buffer.c
selects
CONFIG_TRACE_CLOCK
CONFIG_IRQ_WORK