Re: [patch V2 32/38] posix-cpu-timers: Get rid of zero checks

[Frederic Weisbecker]

On Wed, Aug 21, 2019 at 09:09:19PM +0200, Thomas Gleixner wrote:
> Deactivation of the expiry cache is done by setting all clock caches to
> 0. That requires to have a check for zero in all places which update the
> expiry cache:
> 
> 	if (cache == 0 || new < cache)
> 		cache = new;
> 
> Use U64_MAX as the deactivated value, which allows to remove the zero
> checks when updating the cache and reduces it to the obvious check:
> 
> 	if (new < cache)
> 		cache = new;
> 
> This also removes the weird workaround in do_prlimit() which was required
> to convert a RLIMIT_CPU value of 0 (immediate expiry) to 1 because handing
> in 0 to the posix CPU timer code would have effectively disarmed it.
> 
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Reviewed-by: Frederic Weisbecker <frederic@xxxxxxxxxx>