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From: michi1@michaelblizek.twilightparadox.com (Michael Blizek)
To: kernelnewbies@lists.kernelnewbies.org
Subject: is the tickless kernel now the "standard"?
Date: Mon, 16 May 2011 06:42:20 +0200	[thread overview]
Message-ID: <20110516044220.GA2043@michaelblizek.twilightparadox.com> (raw)
In-Reply-To: <20110515180112.GA21222@kroah.com>

Hi!

On 11:01 Sun 15 May     , Greg KH wrote:
> On Sun, May 15, 2011 at 01:48:43PM -0400, Robert P. J. Day wrote:
...
> >   ok, good to know.  i assume, then, that it's fairly pointless to use
> > the value of "jiffies" for anything that requires even moderate
> > accuracy.  i was poking around the timer code, and i can see this in
> > kernel/time/timekeeping.c:
> 
> No, never access jiffies directly, use the correct delay and timer
> functions instead, they will handle things properly.  And that's the way
> to get correct accuracy if you need it.

When switchint from jiffies+timers to hrtimers what should be used as a
monotonic time source? ktime_get()? What am I supposed to do if
timekeeping_valid_for_hres() returns 0? Can I ignore this?

What does it mean this highres timer are not available during system startup?
Are they running with lower resolution or not at all?

	-Michi

  reply	other threads:[~2011-05-16  4:42 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-15 16:41 is the tickless kernel now the "standard"? Robert P. J. Day
2011-05-15 16:56 ` Greg KH
2011-05-15 17:48   ` Robert P. J. Day
2011-05-15 18:01     ` Greg KH
2011-05-16  4:42       ` Michael Blizek [this message]
2011-05-16  4:46         ` Michael Blizek

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