On Tue, 2007-11-20 at 16:28 -0500, Mathieu Desnoyers wrote:
> * Trond Myklebust ([EMAIL PROTECTED]) wrote:
> > 
> > On Tue, 2007-11-20 at 12:49 -0800, Christoph Lameter wrote:
> > > On Tue, 20 Nov 2007, Mathieu Desnoyers wrote:
> > > 
> > > > > Index: linux-2.6/fs/nfs/iostat.h
> > > > > ===================================================================
> > > > > --- linux-2.6.orig/fs/nfs/iostat.h    2007-11-15 21:17:24.391404458 
> > > > > -0800
> > > > > +++ linux-2.6/fs/nfs/iostat.h 2007-11-15 21:25:33.167654066 -0800
> > > > > @@ -123,7 +123,7 @@ static inline void nfs_inc_server_stats(
> > > > >       int cpu;
> > > > >  
> > > > >       cpu = get_cpu();
> > > > > -     iostats = per_cpu_ptr(server->io_stats, cpu);
> > > > > +     iostats = CPU_PTR(server->io_stats, cpu);
> > > > >       iostats->events[stat] ++;
> > > > 
> > > > Is there a way to change this into a CPU_ADD ?
> > > 
> > > Yes I must have missed that.
> > > 
> > > Could be
> > > 
> > > CPU_INC(server->io_stats->events[stat]);
> > > 
> > > > 
> > > > >       put_cpu_no_resched();
> > > > 
> > > > Why put_cpu_no_resched here ?
> > > 
> > > We do not want to reschedule here? We may have already disabled 
> > > interrupts 
> > > or some such thing.
> > 
> > Some of these statistics are updated from inside a spinlocked
> > environment, hence the put_no_resched().
> > 
> 
> The we could use __get_cpu_var instead ? (since we know preemption is
> _always_ disabled when we are called) ?

We don't know that. I said that _some_ of these statistics are updated
in that way.

Cheers
  Trond

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to