Re: [PATCH] 2.4.0-prerelease: preemptive kernel.

[Nigel Gamble]

On Thu, 4 Jan 2001, Daniel Phillips wrote:
> A more ambitious way to proceed is to change spinlocks so they can sleep
> (not in interrupts of course).  There would not be any extra overhead
> for this on spin_lock (because the sleep test is handled off the fast
> path) but spin_unlock gets a little slower - it has to test and jump on
> a flag if there are sleepers.

I already have a preemption patch that also changes the longest
held spinlocks into sleep locks, i.e. the locks that are routinely
held for > 1ms.  This gives a kernel with very good interactive
response, good enough for most audio apps.

Nigel Gamble                                    [e-mail]
Mountain View, CA, USA.                         http://www.nrg.org/