From: Ingo Molnar <mingo@elte.hu>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Christopher Friesen <cfriesen@nortel.com>,
Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU>,
linux-kernel@vger.kernel.org,
"Paul E. McKenney" <paulmck@us.ibm.com>,
"K.R. Foley" <kr@cybsft.com>,
Thomas Gleixner <tglx@linutronix.de>,
pluto@agmk.net, john cooper <john.cooper@timesys.com>,
Benedikt Spranger <bene@linutronix.de>,
Daniel Walker <dwalker@mvista.com>,
Tom Rini <trini@kernel.crashing.org>,
George Anzinger <george@mvista.com>,
john stultz <johnstul@us.ibm.com>
Subject: Re: test time-warps [was: Re: 2.6.14-rt13]
Date: Tue, 22 Nov 2005 21:52:00 +0100 [thread overview]
Message-ID: <20051122205200.GA17151@elte.hu> (raw)
In-Reply-To: <Pine.LNX.4.58.0511221319560.16745@gandalf.stny.rr.com>
* Steven Rostedt <rostedt@goodmis.org> wrote:
> > > Apparently that's the case.
> >
> > What about periodically re-syncing the TSCs on the cpus? Are they
> > writeable?
>
> I believe you can reset them to zero, but I don't think you can set
> them to anything else. I had to do something similar a few years ago,
> and I don't have the specs in front of me, so this is coming straight
> from memory.
on a reasonably new CPU you ought to be able to set the 64-bit value -
but that doesnt change the fundamental fact: we have no idea how much
time has passed while we were in HLT. Especially with things like
dyntick/noidle we could spend _alot_ of time in HLT, and the TSC could
drift significantly. How do we know how much that is?
Ingo
next prev parent reply other threads:[~2005-11-22 20:52 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-11-15 9:08 2.6.14-rt13 Ingo Molnar
2005-11-15 16:36 ` 2.6.14-rt13 Mark Knecht
2005-11-15 19:57 ` 2.6.14-rt13 Paul E. McKenney
2005-11-16 3:48 ` 2.6.14-rt13 K.R. Foley
2005-11-16 8:40 ` 2.6.14-rt13 Ingo Molnar
2005-11-16 17:02 ` 2.6.14-rt13 Paul E. McKenney
2005-11-18 18:02 ` 2.6.14-rt13 Fernando Lopez-Lezcano
2005-11-18 21:54 ` 2.6.14-rt13 Lee Revell
2005-11-18 22:05 ` 2.6.14-rt13 Fernando Lopez-Lezcano
2005-11-18 22:07 ` 2.6.14-rt13 Ingo Molnar
2005-11-18 22:15 ` 2.6.14-rt13 Lee Revell
2005-11-18 22:25 ` 2.6.14-rt13 Steven Rostedt
2005-11-18 23:36 ` 2.6.14-rt13 Fernando Lopez-Lezcano
2005-11-18 23:57 ` 2.6.14-rt13 Steven Rostedt
2005-11-18 22:41 ` 2.6.14-rt13 Fernando Lopez-Lezcano
2005-11-19 2:39 ` 2.6.14-rt13 Steven Rostedt
2005-11-24 15:07 ` 2.6.14-rt13 Ingo Molnar
2005-11-24 15:21 ` 2.6.14-rt13 Steven Rostedt
2005-11-25 20:56 ` [RFC][PATCH] Runtime switching to idle_poll (was: Re: 2.6.14-rt13) Steven Rostedt
2005-11-26 13:05 ` Ingo Molnar
2005-11-29 2:48 ` [RFC][PATCH] Runtime switching of the idle function [take 2] Steven Rostedt
2005-11-29 3:02 ` Andrew Morton
2005-11-29 3:42 ` Steven Rostedt
2005-11-29 4:01 ` Andrew Morton
2005-11-29 6:44 ` Ingo Molnar
2005-11-29 6:55 ` Nick Piggin
2005-11-29 18:05 ` Andi Kleen
2005-11-29 14:19 ` Steven Rostedt
2005-11-29 14:50 ` Andi Kleen
2005-11-29 15:42 ` Steven Rostedt
2005-12-02 1:27 ` Max Krasnyansky
2005-12-02 1:45 ` Andi Kleen
2005-12-03 2:17 ` Max Krasnyansky
2005-11-29 4:22 ` john stultz
2005-11-29 14:22 ` Steven Rostedt
2005-11-29 13:08 ` Pavel Machek
2005-12-18 15:26 ` Steven Rostedt
2005-11-18 22:13 ` 2.6.14-rt13 Lee Revell
2005-11-18 22:32 ` 2.6.14-rt13 Vojtech Pavlik
2005-11-19 2:28 ` 2.6.14-rt13 George Anzinger
2005-11-19 7:45 ` 2.6.14-rt13 Vojtech Pavlik
2005-11-19 18:27 ` 2.6.14-rt13 Lee Revell
2005-11-21 21:32 ` 2.6.14-rt13 Fernando Lopez-Lezcano
2005-11-21 21:41 ` 2.6.14-rt13 john stultz
[not found] ` <20051121221511.GA7255@elte.hu>
2005-11-21 22:19 ` test time-warps [was: Re: 2.6.14-rt13] Ingo Molnar
2005-11-21 23:08 ` Fernando Lopez-Lezcano
2005-11-21 23:38 ` Fernando Lopez-Lezcano
2005-11-21 23:41 ` john stultz
2005-11-22 1:31 ` Lee Revell
2005-11-22 1:15 ` Steven Rostedt
2005-11-22 11:16 ` Ingo Molnar
2005-11-22 17:49 ` Fernando Lopez-Lezcano
2005-11-22 18:01 ` Christopher Friesen
2005-11-22 18:22 ` Steven Rostedt
2005-11-22 20:52 ` Ingo Molnar [this message]
2005-11-22 11:19 ` 2.6.14-rt13 Ingo Molnar
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