Re: [PATCH 1/6] {set,clear,test}_bit() related cleanup

[Russell King <rmk+lkml@arm.linux.org.uk>]

On Thu, Jan 26, 2006 at 05:14:27PM +0100, Pavel Machek wrote:
> > Index: 2.6-git/include/asm-x86_64/mmu_context.h
> > ===================================================================
> > --- 2.6-git.orig/include/asm-x86_64/mmu_context.h	2006-01-25 19:07:15.000000000 +0900
> > +++ 2.6-git/include/asm-x86_64/mmu_context.h	2006-01-25 19:13:59.000000000 +0900
> > @@ -34,12 +34,12 @@
> >  	unsigned cpu = smp_processor_id();
> >  	if (likely(prev != next)) {
> >  		/* stop flush ipis for the previous mm */
> > -		clear_bit(cpu, &prev->cpu_vm_mask);
> > +		cpu_clear(cpu, prev->cpu_vm_mask);
> >  #ifdef CONFIG_SMP
> >  		write_pda(mmu_state, TLBSTATE_OK);
> >  		write_pda(active_mm, next);
> >  #endif
> > -		set_bit(cpu, &next->cpu_vm_mask);
> > +		cpu_set(cpu, next->cpu_vm_mask);
> >  		load_cr3(next->pgd);
> >  
> >  		if (unlikely(next->context.ldt != prev->context.ldt)) 
> 
> cpu_set sounds *very* ambiguous. We have thing called cpusets, for
> example. I'd not guess that is set_bit in cpu endianity (is it?).

That's a problem for the cpusets folk - cpu_set predates them by a
fair time - it's part of the cpumask API.  See include/linux/cpumask.h

Also, since cpu_vm_mask is a cpumask_t, the above change to me looks
like a bug fix in its own right.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 Serial core