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

Russell King
2006-01-26T16:47:45Z

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