Re: [RFC 4/9] Atomic reclaim: Save irq flags in vmscan.c

Andi Kleen
2007-08-14T22:24:01Z

> Ok I have a vague idea on how this could but its likely that the
> changes make things worse rather than better. Additional reference to a
> new cacheline (per cpu but still), preempt disable. Lots of code at all
> call sites. Interrupt enable/disable is quite efficient in recent
> processors.

The goal of this was not to be faster than interrupt disable,
but to avoid the interrupt latency impact. This might be a problem
when spending a lot of time inside the locks.

-Andi