Re: [PATCH 1/3 v2] Docs: admin/kernel-parameters: edit a few boot options

[Steven Rostedt]

On Thu, 31 Mar 2022 20:09:25 -0700
Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote:

> @@ -5908,6 +5910,8 @@
>  	trace_buf_size=nn[KMG]
>  			[FTRACE] will set tracing buffer size on each cpu.
>  
> +	trace_clock=	[FTRACE] See Documentation/trace/ftrace.rst

	trace_clock=	[FTRACE] Set the clock used for tracing events
			at boot up.
			local - Use the per CPU time stamp counter
				(converted into nanoseconds). Fast, but
				depending on the architecture, may not be
				in sync between CPUs.
			global - Event time stamps are synchronize across
				CPUs. May be slower than the local clock,
				but better for some race conditions.
			counter - Simple counting of events (1, 2, ..)
				note, some counts may be skipped due to the
				infrastructure grabbing the clock more than
				once per event.
			uptime - Use jiffies as the time stamp.
			perf - Use the same clock that perf uses.
			mono - Use ktime_get_mono_fast_ns() for time stamps.
			mono_raw - Use ktime_get_raw_fast_ns() for time
				stamps.
			boot - Use ktime_get_boot_fast_ns() for time stamps.
			Architectures may add more clocks. See
			Documentation/trace/ftrace.rst for more details.

-- Steve


> +
>  	trace_event=[event-list]
>  			[FTRACE] Set and start specified trace events in order
>  			to facilitate early boot debugging. The event-list is a