Support unified trace buffer instead of relayfs, since relay will be replaced by it. see kernel/trace/ring_buffer.c.
I think there might be another plan that stap generates ftrace-plug-in tracer instead of using ring-buffer directly.
*** Bug 9801 has been marked as a duplicate of this bug. ***
Let's assess whether the ring buffer widget, or the larger control structures around it in ftrace, are relevant/useful to systemtap. We need at least: - access to the ftrace buffering stuff from modules - the ring buffers need to contain formatted ascii, since that is what scripts produce, and not rely on subsequent trace_iter printing like current ftrace engines; maybe reuse ftrace_printk - per-script trace files (instead of /debugfs/tracing/trace intermingled) ... unless some goofy multiplexing is the only way - probably no connection with the overall control switch /tracing/tracing_enabled), since scripts come and go at any time
-DSTP_USE_RING_BUFFER does this.