Messages in this thread | | | Date | Mon, 4 Jan 2016 14:54:20 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH v2 17/32] arm: define __smp_xxx |
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On Mon, Jan 04, 2016 at 02:36:58PM +0100, Peter Zijlstra wrote: > On Sun, Jan 03, 2016 at 11:12:44AM +0200, Michael S. Tsirkin wrote: > > On Sat, Jan 02, 2016 at 11:24:38AM +0000, Russell King - ARM Linux wrote: > > > > My only concern is that it gives people an additional handle onto a > > > "new" set of barriers - just because they're prefixed with __* > > > unfortunately doesn't stop anyone from using it (been there with > > > other arch stuff before.) > > > > > > I wonder whether we should consider making the smp memory barriers > > > inline functions, so these __smp_xxx() variants can be undef'd > > > afterwards, thereby preventing drivers getting their hands on these > > > new macros? > > > > That'd be tricky to do cleanly since asm-generic depends on > > ifndef to add generic variants where needed. > > > > But it would be possible to add a checkpatch test for this. > > Wasn't the whole purpose of these things for 'drivers' (namely > virtio/xen hypervisor interaction) to use these?
Ah, I see, you add virt_*mb() stuff later on for that use case.
So, assuming everybody does include asm-generic/barrier.h, you could simply #undef the __smp version at the end of that, once we've generated all the regular primitives from it, no?
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