lkml.org 
[lkml]   [2006]   [Oct]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [RFC] The New and Improved Logdev (now with kprobes!)
From
Date
On Thu, 2006-10-05 at 14:38 -0400, Steven Rostedt wrote:
> On Thu, 5 Oct 2006, Daniel Walker wrote:
>
> > On Thu, 2006-10-05 at 14:09 -0400, Steven Rostedt wrote:
> >
> > >
> > > My problem with using a timestamp, is that I ran logdev on too many archs.
> > > So I need to have a timestamp that I can get to that is always reliable.
> > > How does LTTng get the time for different archs? Does it have separate
> > > code for each arch?
> > >
> >
> > I just got done updating a patchset that exposes the clocksources from
> > generic time to take low level time stamps.. But even without that you
> > can just call gettimeofday() directly to get a timestamp .
> >
>
> unless you're tracing something that his holding the xtime_lock ;-)

That's part of the reason for the changes that I made to the clocksource
API . It makes it so instrumentation, with other things, can generically
read a low level cycle clock. Like on PPC you would read the
decrementer, and on x86 you would read the TSC . However, the
application has no idea what it's reading.

I submitted one version to LKML already, but I'm planning to submit
another version shortly.

Daniel

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-10-05 20:51    [W:0.059 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site