Re: Name cache locking issue?

[Jason Thorpe <thorpej%shagadelic.org@localhost>]

We should make it MI.

But why not just use an rwlock?

-- thorpej@iPhone

On Apr 11, 2008, at 4:59 PM, Andrew Doran <ad%netbsd.org@localhost> wrote:

> On Fri, Apr 11, 2008 at 04:21:17PM -0700, Jason Thorpe wrote:
>
> > On Apr 11, 2008, at 8:25 AM, Andrew Doran wrote:
> > > Module Name:    src
> > > Committed By:    ad
> > > Date:        Fri Apr 11 15:25:24 UTC 2008
> > >
> > > Modified Files:
> > >    src/sys/kern: kern_cpu.c vfs_cache.c
> > >    src/sys/sys: cpu_data.h namei.src
> > >
> > > Log Message:
> > > Restructure the name cache code to eliminate most lock contention
> > > resulting from forward lookups. Discussed on tech-kern@.
> >
> > Hm, is cache_lock_cpus() safe if CPU_INFO_ITERATOR() happens to  
> > return
> > the CPUs in a different order on different CPUs?
>
> A quick check shows that they all start from the same point (the  
> first CPU)
> so it should be OK. I guess we should document that somewhere, and  
> maybe get
> rid of the MD macro altogether.
>
> Andrew