From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: Regression on rt kernel while using POSIX timers
Date: Tue, 7 Mar 2017 18:03:03 +0100 (CET)
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To: "Patel, Vedang" <vedang.patel@intel.com>
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On Tue, 7 Mar 2017, Patel, Vedang wrote:
> On Mon, 2017-03-06 at 12:29 +0100, Thomas Gleixner wrote:
> 
> > This is simple to achieve for timers where the signal is directed to
> > a thread, but it's way more complex for process wide signal delivery.
> > 
> So, does this mean that we should be asking people not to use POSIX
> timers until this is corrected?

Well, we always recommended clock_nanosleep() to be used and to avoid
signal based timers when ever possible.

> Also, Is there a way to specify which ktimersoftd thread (essentially
> selecting a particular CPU)to use while creating a timer? Currently,
> the ktimersoftd thread corresponding to the thread on which the CPU is
> running is being used by cyclictest. This would prevent the bounce
> between ktimersoftd and cyclictest thread when both of them are on the
> same CPU.

Nope. This is even more complex than you describe it and no, we definitely
don't want to think about this in the first place.

Thanks,

	tglx