On Sat, Jan 02, 2016 at 11:24:38AM +0000, Russell King - ARM Linux wrote:

On Thu, Dec 31, 2015 at 09:07:59PM +0200, Michael S. Tsirkin wrote:

quoted

This defines __smp_xxx barriers for arm,
for use by virtualization.

smp_xxx barriers are removed as they are
defined correctly by asm-generic/barriers.h

This reduces the amount of arch-specific boiler-plate code.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

In combination with patch 14, this looks like it should result in no
change to the resulting code.

Acked-by: Russell King <redacted>

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.

-- 
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