Re: [Xen-devel] [PATCH v3 39/41] xen/events: use virt_xxx barriers

2016-01-11 Thread David Vrabel
On 10/01/16 14:21, Michael S. Tsirkin wrote: > drivers/xen/events/events_fifo.c uses rmb() to communicate with the > other side. > > For guests compiled with CONFIG_SMP, smp_rmb would be sufficient, so > rmb() here is only needed if a non-SMP guest runs on an SMP host. > > Switch to the virt_rmb

[Xen-devel] [PATCH v3 39/41] xen/events: use virt_xxx barriers

2016-01-10 Thread Michael S. Tsirkin
drivers/xen/events/events_fifo.c uses rmb() to communicate with the other side. For guests compiled with CONFIG_SMP, smp_rmb would be sufficient, so rmb() here is only needed if a non-SMP guest runs on an SMP host. Switch to the virt_rmb barrier which serves this exact purpose. Pull in asm/barri