Mailing List Archive: [PATCH 2/9] xen/arm: introduce PGC

[PATCH 2/9] xen/arm: introduce PGC_reserved

Jun 6, 2021, 7:43 PM

Post #1 of 3 (16 views)

In order to differentiate pages of static memory, from those allocated from
heap, this patch introduces a new page flag PGC_reserved to tell.

Signed-off-by: Penny Zheng <penny.zheng@arm.com>
---
changes v2:
- remove unused reserved field in struct page_info
- remove unused helper page_get_reserved_owner and page_set_reserved_owner
---
xen/include/asm-arm/mm.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h
index 0b7de3102e..7034fae1b6 100644
--- a/xen/include/asm-arm/mm.h
+++ b/xen/include/asm-arm/mm.h
@@ -108,6 +108,9 @@ struct page_info
/* Page is Xen heap? */
#define _PGC_xen_heap PG_shift(2)
#define PGC_xen_heap PG_mask(1, 2)
+ /* Page is reserved */
+#define _PGC_reserved PG_shift(3)
+#define PGC_reserved PG_mask(1, 3)
/* ... */
/* Page is broken? */
#define _PGC_broken PG_shift(7)
--
2.25.1

Re: [PATCH 2/9] xen/arm: introduce PGC_reserved [ In reply to ]

julien at xen

Jun 30, 2021, 10:44 AM

Post #2 of 3 (16 views)

Permalink

Hi Penny,

On 07/06/2021 03:43, Penny Zheng wrote:
> In order to differentiate pages of static memory, from those allocated from
> heap, this patch introduces a new page flag PGC_reserved to tell.

I would prefer if this patch is folded in the patch first using it. This
will be easier to understand how this flag will be used.

Cheers,

>
> Signed-off-by: Penny Zheng <penny.zheng@arm.com>
> ---
> changes v2:
> - remove unused reserved field in struct page_info
> - remove unused helper page_get_reserved_owner and page_set_reserved_owner
> ---
> xen/include/asm-arm/mm.h | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h
> index 0b7de3102e..7034fae1b6 100644
> --- a/xen/include/asm-arm/mm.h
> +++ b/xen/include/asm-arm/mm.h
> @@ -108,6 +108,9 @@ struct page_info
> /* Page is Xen heap? */
> #define _PGC_xen_heap PG_shift(2)
> #define PGC_xen_heap PG_mask(1, 2)
> + /* Page is reserved */
> +#define _PGC_reserved PG_shift(3)
> +#define PGC_reserved PG_mask(1, 3)
> /* ... */
> /* Page is broken? */
> #define _PGC_broken PG_shift(7)
>

--
Julien Grall

RE: [PATCH 2/9] xen/arm: introduce PGC_reserved [ In reply to ]

Penny.Zheng at arm

Jul 4, 2021, 8:09 PM

Post #3 of 3 (16 views)

Permalink

Hi Julien

Sorry for so long to respond, just back from a long holiday. ????

> -----Original Message-----
> From: Julien Grall <julien@xen.org>
> Sent: Thursday, July 1, 2021 1:44 AM
> To: Penny Zheng <Penny.Zheng@arm.com>; xen-devel@lists.xenproject.org;
> sstabellini@kernel.org; jbeulich@suse.com
> Cc: Bertrand Marquis <Bertrand.Marquis@arm.com>; Wei Chen
> <Wei.Chen@arm.com>
> Subject: Re: [PATCH 2/9] xen/arm: introduce PGC_reserved
>
> Hi Penny,
>
> On 07/06/2021 03:43, Penny Zheng wrote:
> > In order to differentiate pages of static memory, from those allocated
> > from heap, this patch introduces a new page flag PGC_reserved to tell.
>
> I would prefer if this patch is folded in the patch first using it. This will be
> easier to understand how this flag will be used.
>
> Cheers,

Sure, I'll re-organize this commit.

>
> >
> > Signed-off-by: Penny Zheng <penny.zheng@arm.com>
> > ---
> > changes v2:
> > - remove unused reserved field in struct page_info
> > - remove unused helper page_get_reserved_owner and
> > page_set_reserved_owner
> > ---
> > xen/include/asm-arm/mm.h | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h
> index
> > 0b7de3102e..7034fae1b6 100644
> > --- a/xen/include/asm-arm/mm.h
> > +++ b/xen/include/asm-arm/mm.h
> > @@ -108,6 +108,9 @@ struct page_info
> > /* Page is Xen heap? */
> > #define _PGC_xen_heap PG_shift(2)
> > #define PGC_xen_heap PG_mask(1, 2)
> > + /* Page is reserved */
> > +#define _PGC_reserved PG_shift(3)
> > +#define PGC_reserved PG_mask(1, 3)
> > /* ... */
> > /* Page is broken? */
> > #define _PGC_broken PG_shift(7)
> >
>
> --
> Julien Grall

Cheers

--
Penny Zheng