Revert "virtio_ring: Update weak barriers to use dma_wmb/rmb"

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This reverts commit 9e1a27ea42.

While that commit optimizes !CONFIG_SMP, it mixes
up DMA and SMP concepts, making the code hard
to figure out.

A better way to optimize this is with the new __smp_XXX
barriers.

As a first step, go back to full rmb/wmb barriers
for !SMP.
We switch to __smp_XXX barriers in the next patch.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

...

This commit is contained in:

Michael S. Tsirkin 2015-12-20 13:52:10 +02:00

parent 6a65d26385

commit d307fb16f7

1 changed files with 19 additions and 4 deletions

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include/linux/virtio_ring.h

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