Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Jan Beulich
On 05.08.15 at 15:18, julien.gr...@citrix.com wrote: On 05/08/15 13:46, Andrew Cooper wrote: On 05/08/15 13:36, Julien Grall wrote: So we need to introduce the concept of in each definition. This patch makes clear that MFN and GFN is always 4KB and PFN may vary. Is (or rather will) a 4K

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Julien Grall
Hi Jan, On 12/08/2015 08:16, Jan Beulich wrote: On 05.08.15 at 15:18, julien.gr...@citrix.com wrote: On 05/08/15 13:46, Andrew Cooper wrote: On 05/08/15 13:36, Julien Grall wrote: So we need to introduce the concept of in each definition. This patch makes clear that MFN and GFN is always 4KB

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Julien Grall
On 12/08/15 11:33, Jan Beulich wrote: On 12.08.15 at 11:57, julien.gr...@citrix.com wrote: On 12/08/2015 08:16, Jan Beulich wrote: On 05.08.15 at 15:18, julien.gr...@citrix.com wrote: On 05/08/15 13:46, Andrew Cooper wrote: On 05/08/15 13:36, Julien Grall wrote: So we need to introduce the

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Jan Beulich
On 12.08.15 at 11:57, julien.gr...@citrix.com wrote: On 12/08/2015 08:16, Jan Beulich wrote: On 05.08.15 at 15:18, julien.gr...@citrix.com wrote: On 05/08/15 13:46, Andrew Cooper wrote: On 05/08/15 13:36, Julien Grall wrote: So we need to introduce the concept of in each definition. This

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Jan Beulich
On 12.08.15 at 13:13, julien.gr...@citrix.com wrote: On 12/08/15 11:33, Jan Beulich wrote: On 12.08.15 at 11:57, julien.gr...@citrix.com wrote: On 12/08/2015 08:16, Jan Beulich wrote: On 05.08.15 at 15:18, julien.gr...@citrix.com wrote: When the backend is 64K, it will map the foreign 4K at

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Julien Grall
On 12/08/15 12:58, Jan Beulich wrote: On 12.08.15 at 13:13, julien.gr...@citrix.com wrote: On 12/08/15 11:33, Jan Beulich wrote: On 12.08.15 at 11:57, julien.gr...@citrix.com wrote: On 12/08/2015 08:16, Jan Beulich wrote: On 05.08.15 at 15:18, julien.gr...@citrix.com wrote: When the backend

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-12 Thread Jan Beulich
On 12.08.15 at 14:57, julien.gr...@citrix.com wrote: On 12/08/15 12:58, Jan Beulich wrote: On 12.08.15 at 13:13, julien.gr...@citrix.com wrote: On 12/08/15 11:33, Jan Beulich wrote: On 12.08.15 at 11:57, julien.gr...@citrix.com wrote: On 12/08/2015 08:16, Jan Beulich wrote: On 05.08.15 at

[Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-05 Thread Julien Grall
From: Stefano Stabellini stefano.stabell...@eu.citrix.com ARM64 is able to support 64KB and 4KB page granularities. While the guest will support both granularities, Xen and hypercall interface will always be in 4KB. Signed-off-by: Stefano Stabellini stefano.stabell...@citrix.com Signed-off-by:

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-05 Thread Andrew Cooper
On 05/08/15 12:28, Julien Grall wrote: From: Stefano Stabellini stefano.stabell...@eu.citrix.com ARM64 is able to support 64KB and 4KB page granularities. While the guest will support both granularities, Xen and hypercall interface will always be in 4KB. Signed-off-by: Stefano Stabellini

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-05 Thread Ian Campbell
On Wed, 2015-08-05 at 12:40 +0100, Andrew Cooper wrote: 64K granularity is also similar to 2M/1G superpages in their handling, the difference being that 64K can't be subdivided if necessary? 64K is actually a separate basic granule (to use the ARM term), i.e. alternative to the 4K leaf page

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-05 Thread Julien Grall
On 05/08/15 12:40, Andrew Cooper wrote: I think a section about granularity is worthwhile, but probably a separate paragraph. I think it is also worth keeping Xen's idea of memory all at 4K, and in cases where 64K is in use, require appropriate alignment in the parameter. Which would confuse

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-05 Thread Andrew Cooper
On 05/08/15 13:36, Julien Grall wrote: On 05/08/15 12:40, Andrew Cooper wrote: I think a section about granularity is worthwhile, but probably a separate paragraph. I think it is also worth keeping Xen's idea of memory all at 4K, and in cases where 64K is in use, require appropriate

Re: [Xen-devel] [RFC 1/2] xen/mm: Clarify the granularity for each Frame Number

2015-08-05 Thread Julien Grall
Hi, On 05/08/15 13:46, Andrew Cooper wrote: On 05/08/15 13:36, Julien Grall wrote: On 05/08/15 12:40, Andrew Cooper wrote: I think a section about granularity is worthwhile, but probably a separate paragraph. I think it is also worth keeping Xen's idea of memory all at 4K, and in cases