Messages in this thread | | | Date | Wed, 16 Oct 2013 19:11:53 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH 6/6] percpu: Add preemption checks to __this_cpu ops |
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On Wed, Oct 16, 2013 at 12:52:38PM -0400, Steven Rostedt wrote: > On Wed, 16 Oct 2013 18:25:37 +0200 > Peter Zijlstra <peterz@infradead.org> wrote: > > > But yes, the way its set-up an arch could indeed provide __this_cup_$op > > itself -- without providing the _$n variants; in which case the > > raw_cpu_$op provided by you is broken. > > > > Can't we have a 'simple' coccinelle script rename the entire __this_cpu* > > implementation over to raw_cpu* and then provide generic __this_cpu* -> > > raw_cpu maps? > > > > Perhaps we should match the way spinlocks are. > > > this_cpu*() be the normal use. > > raw_this_cpu() could perhaps not do the checks? > > arch_this_cpu() be the architecture specific version of this_cpu*
In that case we'd need to do something like:
this_cpu_$op -> this_cpu_$op_irq (disables irqs itself) __this_cpu_$op -> this_cpu_$op (with check) -> raw_cpu_$op (without the check)
I don't think the arch bits feature heavily for percpu; normally an arch provides __this_cpu_$op_$n; raw_cpu_$op_$n in my latest proposal.
Anyway; I don't think the spinlock pattern matches too good and I don't mind the proposed:
this_cpu_$op (disables IRQs itself) __this_cpu_$op (with preemption check) raw_cpu_$op (without preemption check)
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