lkml.org 
[lkml]   [2018]   [Apr]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2 1/2] trace: Default to using trace_global_clock if sched_clock is unstable
On Fri, 30 Mar 2018 16:01:31 +0100
Chris Wilson <chris@chris-wilson.co.uk> wrote:

> Across suspend, we may see a very large drift in timestamps if the sched
> clock is unstable, prompting the global trace's ringbuffer code to warn
> and suggest switching to the global clock. Preempt this request by
> detecting when the sched clock is unstable (determined during
> late_initcall) and automatically switching the default clock over to
> trace_global_clock.
>
> This should prevent requiring user interaction to resolve warnings such
> as:
>
> Delta way too big! 18446743856563626466 ts=18446744054496180323 write stamp = 197932553857
> If you just came from a suspend/resume,
> please switch to the trace global clock:
> echo global > /sys/kernel/debug/tracing/trace_clock
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
> ---
> v2: Tell the user what's happening and what they can do to correct it.
>

Thanks, I pulled them in. I'll start testing them before I post to git.

-- Steve

\
 
 \ /
  Last update: 2018-04-02 17:18    [W:0.072 / U:0.100 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site