Shared/exclusive (rw) locks

[Peter Pentchev]

On Tue, Jul 06, 2004 at 03:55:49PM +0600, ngl wrote:
> 
> ----- Original Message ----- 
> From: "Tim Robbins" <tjr at freebsd.org>
> To: "ngl" <ngl at ur.ru>
> Cc: <freebsd-stable at freebsd.org>
> Sent: Tuesday, July 06, 2004 1:17 PM
> Subject: Re: Shared/exclusive (rw) locks
> 
> 
> > On Tue, Jul 06, 2004 at 12:45:27PM +0600, ngl wrote:
> > > That means, freebsd stable has no spin rwlocks ?
> >
> > Right. Reader-writer spinlocks would not be very useful in FreeBSD 4;
> because
> > only one thread can be running in the kernel at once
> 
> Forgive for my importunity, but what about smp ?

On FreeBSD 4.x, the kernel only ever runs on one CPU, the CPU that the
system started on.  The other CPU's are only used for scheduling
userland processes.

G'luck,
Peter

-- 
Peter Pentchev	roam at ringlet.net    roam at sbnd.net    roam at FreeBSD.org
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If wishes were fishes, the antecedent of this conditional would be true.
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