Re: [PATCH v2][5.10, 5.15, 6.1][1/1] hrtimer: Ignore slack time for RT tasks in schedule_hrtimeout_range()

["MOESSBAUER, Felix" <felix.moessbauer@siemens.com>]

On Tue, 2024-02-20 at 15:32 +0100, Greg KH wrote:
> On Tue, Feb 20, 2024 at 01:34:03PM +0100, Felix Moessbauer wrote:
> > From: Davidlohr Bueso <dave@stgolabs.net>
> > 
> > commit 0c52310f260014d95c1310364379772cb74cf82d upstream.
> > 
> > While in theory the timer can be triggered before expires + delta,
> > for the
> > cases of RT tasks they really have no business giving any lenience
> > for
> > extra slack time, so override any passed value by the user and
> > always use
> > zero for schedule_hrtimeout_range() calls. Furthermore, this is
> > similar to
> > what the nanosleep(2) family already does with current-
> > >timer_slack_ns.
> > 
> > Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
> > Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> > Link:
> > https://lore.kernel.org/r/20230123173206.6764-3-dave@stgolabs.net
> 
> You can't forward on a patch without signing off on it as well :(

Ok, thanks for the info. I'll add the signoff and send a v3.

> 
> And this is already in the 6.1.53 release, why apply it again?

I can't find it there and also the change is not included in linux-
6.1.y or 6.1.53. There is another commit referencing this patch (linux-
6.1.y, fd4d61f85e7625cb21a7eff4efa1de46503ed2c3), but the "hrtimer:
Ignore slack time ..." patch did not get backported so far.
I also checked the source of v6.1.y and could not find the related
change. Which commit exactly are you referring to?

Felix

> 
> confused,
> 
> greg k-h

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