Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt

Alan Cox
2005-07-14T22:43:50Z

> just doesn't realize that the latter is a bit more complicated exactly
> because the latter is a hell of a lot more POWERFUL. Trying to get rid of
> jiffies for some religious reason is _stupid_.

Getting rid of jiffies in its current form is a huge win for very
non-religious reasons. Jiffies is expensive in power management and
virtualisation because you have to maintain it.

Swap jiffies for jiffies() and the world gets a lot better.

In actual fact you also want to fix users of

while(time_before(foo, jiffies)) { whack(mole); }

to become

init_timeout(&timeout);
timeout.expires = jiffies + n
add_timeout(&timeout);
while(!timeout_expired(&timeout)) {}

Which is a trivial wrapper around timers as we have them now