Re: [PATCH] virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-10 Thread Rusty Russell
Alexander Duyck writes: > This change makes it so that instead of using smp_wmb/rmb which varies > depending on the kernel configuration we can can use dma_wmb/rmb which for > most architectures should be equal to or slightly more strict than > smp_wmb/rmb. > > The advantage to this is that these

Re: [PATCH] virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-08 Thread Alexander Duyck
On 04/08/2015 11:37 AM, Michael S. Tsirkin wrote: On Wed, Apr 08, 2015 at 07:41:49AM -0700, Alexander Duyck wrote: On 04/08/2015 01:42 AM, Michael S. Tsirkin wrote: On Tue, Apr 07, 2015 at 05:47:42PM -0700, Alexander Duyck wrote: This change makes it so that instead of using smp_wmb/rmb which

Re: [PATCH] virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-08 Thread Michael S. Tsirkin
On Wed, Apr 08, 2015 at 07:41:49AM -0700, Alexander Duyck wrote: > > On 04/08/2015 01:42 AM, Michael S. Tsirkin wrote: > >On Tue, Apr 07, 2015 at 05:47:42PM -0700, Alexander Duyck wrote: > >>This change makes it so that instead of using smp_wmb/rmb which varies > >>depending on the kernel configur

Re: [PATCH] virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-08 Thread Alexander Duyck
On 04/08/2015 01:42 AM, Michael S. Tsirkin wrote: On Tue, Apr 07, 2015 at 05:47:42PM -0700, Alexander Duyck wrote: This change makes it so that instead of using smp_wmb/rmb which varies depending on the kernel configuration we can can use dma_wmb/rmb which for most architectures should be equal

Re: [PATCH] virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-08 Thread Michael S. Tsirkin
On Tue, Apr 07, 2015 at 05:47:42PM -0700, Alexander Duyck wrote: > This change makes it so that instead of using smp_wmb/rmb which varies > depending on the kernel configuration we can can use dma_wmb/rmb which for > most architectures should be equal to or slightly more strict than > smp_wmb/rmb.

[PATCH] virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-07 Thread Alexander Duyck
This change makes it so that instead of using smp_wmb/rmb which varies depending on the kernel configuration we can can use dma_wmb/rmb which for most architectures should be equal to or slightly more strict than smp_wmb/rmb. The advantage to this is that these barriers are available to uniprocess