Re: setitimer expire too early (Kernel 2.4)

[Marcelo Tosatti <marcelo.tosatti@cyclades.com>]

On Fri, Jul 01, 2005 at 02:14:42PM -0700, George Anzinger wrote:
> Marcelo Tosatti wrote:
> >Hi Olivier,
> >
> >On Fri, Jul 01, 2005 at 07:52:12PM +0200, Olivier Croquette wrote:
> >
> >>Andrew Morton wrote:
> >>
> >>>>Linus, Andrew, do you consider this critical enough to be merged to 
> >>>>the v2.4 tree?
> >>>
> >>>
> >>>No.  I'd expect this would hurt more people than it would benefit.
> >>
> >>
> >>Probably.
> >>Does that mean that the kernel 2.4 will keep this bug for ever?
> >
> >
> >Probably, yes. I've never heard such complaints before your message.
> >
> >The right way to do it seems something else BTW:
> >
> >quoting Nish Aravamudan (http://lkml.org/lkml/2005/4/29/240):
> >
> >Your patch is the only way to guarantee no early timeouts, as far as I 
> >know.
> >
> >Really, what you want is:
> >
> >on adding timers, take the ceiling of the interval into which it could be 
> >added
> >on expiring timers, take the floor
> >
> >This combination guarantees no timers go off early (and takes away
> >many of these corner cases). I do exactly this in my patch, btw.
> 
> IMNSHO that is just another way of saying "add 1 to the jiffie count" which 
> is what the proposed patch does.

Hi George, 

OK - I'll write a test case to confirm there are no such longer delay 
regressions as Paulo suggests.  

Thanks for your advice.