Re: [PATCH 1/3 v2] Docs: admin/kernel-parameters: edit a few boot options
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
- To: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
- Subject: Re: [PATCH 1/3 v2] Docs: admin/kernel-parameters: edit a few boot options
- From: Steven Rostedt <rostedt@xxxxxxxxxxx>
- Date: Fri, 1 Apr 2022 12:03:05 -0400
- Cc: linux-kernel@xxxxxxxxxxxxxxx, Heiko Carstens <hca@xxxxxxxxxxxxx>, Vasily Gorbik <gor@xxxxxxxxxxxxx>, Alexander Gordeev <agordeev@xxxxxxxxxxxxx>, Christian Borntraeger <borntraeger@xxxxxxxxxxxxx>, Sven Schnelle <svens@xxxxxxxxxxxxx>, linux-s390@xxxxxxxxxxxxxxx, Ingo Molnar <mingo@xxxxxxxxxx>, "David S. Miller" <davem@xxxxxxxxxxxxx>, sparclinux@xxxxxxxxxxxxxxx, Michael Ellerman <mpe@xxxxxxxxxxxxxx>, linux-ia64@xxxxxxxxxxxxxxx, "Rafael J. Wysocki" <rafael@xxxxxxxxxx>, Pavel Machek <pavel@xxxxxx>, Len Brown <lenb@xxxxxxxxxx>, linux-pm@xxxxxxxxxxxxxxx, linux-acpi@xxxxxxxxxxxxxxx, Johannes Weiner <hannes@xxxxxxxxxxx>, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>, Jonathan Corbet <corbet@xxxxxxx>, linux-doc@xxxxxxxxxxxxxxx
- In-reply-to: <20220401030927.12023-2-rdunlap@infradead.org>
- References: <20220401030927.12023-1-rdunlap@infradead.org> <20220401030927.12023-2-rdunlap@infradead.org>
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
[Index of Archives]
[Linux Kernel]
[Sparc Linux]
[DCCP]
[Linux ARM]
[Yosemite News]
[Linux SCSI]
[Linux x86_64]
[Linux for Ham Radio]