Re: [patch] inode-lock-break.patch, 2.6.8-rc3-mm2

Ingo Molnar
2004-08-09T11:22:08Z

* Andrew Morton <akpm@osdl.org> wrote:

> > tested on x86, the patch solves these particular latencies.
>
> On uniprocessor only. What are we going to do about SMP?

i believe we should 'ignore' SMP spinlock starvation for now: it will be
fixed in a natural way with the most-spinlocks-are-mutexes solution,
with that approach all preemption wishes of other CPUs are properly
expressed in terms of need_resched().

alternatively the 'release the lock every 128 iterations and do a
cpu_relax()' hack could be used - but i think that doesnt solve the SMP
issues in a sufficiant way.

Ingo