On 20/08/15 10:59, David Vrabel wrote: > On 07/08/15 17:46, Julien Grall wrote: >> For ARM64 guests, Linux is able to support either 64K or 4K page >> granularity. Although, the hypercall interface is always based on 4K >> page granularity. >> >> With 64K page granularity, a single page will be spread over multiple >> Xen frame. >> >> To avoid splitting the page into 4K frame, take advantage of the >> extent_order field to directly allocate/free chunk of the Linux page >> size. >> >> Note that PVMMU is only used for PV guest (which is x86) and the page >> granularity is always 4KB. Some BUILD_BUG_ON has been added to ensure >> that because the code has not been modified. > [...] >> #ifdef CONFIG_XEN_HAVE_PVMMU >> + /* We don't support PV MMU when Linux and Xen is using >> + * different page granularity. >> + */ >> + BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE); > > You don't need this BUILD_BUG_ON() twice.
I put twice the BUILD_BUG_ON so if we ever decide to drop one of the #ifdef CONFIG_XEN_HAVE_PVMMU, the check will still be present. So I'd like to keep it. > Otherwise, > > Reviewed-by: David Vrabel <david.vra...@citrix.com> Based on the discussion with Stefano I rework a bit the balloon code to re-use lru field (see [1]), so I won't retain your reviewed-by on the next series. Regards, [1] http://lists.xen.org/archives/html/xen-devel/2015-08/msg00781.html -- Julien Grall -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
