linux-kernel - Re: [PATCH v4 3/3] tracing: add additional marks to signal very large delay

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20141120063303.GC27177@byungchulpark-X58A-UD3R>
Date:	Thu, 20 Nov 2014 15:33:03 +0900
From:	Byungchul Park <byungchul.park@....com>
To:	Namhyung Kim <namhyung@...nel.org>
Cc:	Steven Rostedt <rostedt@...dmis.org>, mingo@...hat.com,
	linux-kernel@...r.kernel.org, seungho1.park@....com,
	jolsa@...hat.com
Subject: Re: [PATCH v4 3/3] tracing: add additional marks to signal very
 large delay

Hi, namhyung

On Thu, Nov 20, 2014 at 03:11:19PM +0900, Namhyung Kim wrote:
> On Wed, 19 Nov 2014 13:35:15 -0500, Steven Rostedt wrote:
> > On Tue, 18 Nov 2014 14:57:26 +0900
> > byungchul.park@....com wrote:
> >
> >> From: Byungchul Park <byungchul.park@....com>
> >> 
> >> Currently, some tracers tracing latency print "!" or "+" just after time
> >> to signal overhead, depending on the interval between events. Even it is
> >> usually enough to do that, we sometimes need to be signaled for bigger
> >> interval than 100 micro seconds.
> >> 
> >> Signed-off-by: Byungchul Park <byungchul.park@....com>
> >> ---
> >>  Documentation/trace/ftrace.txt |    8 +++++---
> >>  kernel/trace/trace_output.c    |   23 ++++++++++++++++++-----
> >>  2 files changed, 23 insertions(+), 8 deletions(-)
> >> 
> >> diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
> >> index f827e2f..64efb3e 100644
> >> --- a/Documentation/trace/ftrace.txt
> >> +++ b/Documentation/trace/ftrace.txt
> >> @@ -680,9 +680,11 @@ The above is mostly meaningful for kernel developers.
> >>  	 needs to be fixed to be only relative to the same CPU.
> >>  	 The marks are determined by the difference between this
> >>  	 current trace and the next trace.
> >> -	  '!' - greater than preempt_mark_thresh (default 100)
> >> -	  '+' - greater than 1 microsecond
> >> -	  ' ' - less than or equal to 1 microsecond.
> >> +	  '$' - greater than 1 second
> >> +	  '#' - greater than 1000 microsecond
> >> +	  '!' - greater than 100 microsecond
> >> +	  '+' - greater than 10 microsecond
> 
> I've noticed that it's now changed from 1 msec to 10 msec.  Is it okay?
>

Yes it is okay. Steve asked for changing the value. :)

Thanks,
Byungchul
 
> Thanks,
> Namhyung
> 
> 
> >> +	  ' ' - less than or equal to 10 microsecond.
> >>  
> >>    The rest is the same as the 'trace' file.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/