[PATCH v6 09/15] xen/page_alloc: introduce preserved page flags macro

[Carlo Nonato <carlo.nonato@xxxxxxxxxxxxxxx>]

PGC_static and PGC_extra are flags that needs to be preserved when assigning
a page. Define a new macro that groups those flags and use it instead of
or'ing every time.

Signed-off-by: Carlo Nonato <carlo.nonato@xxxxxxxxxxxxxxx>
---
v6:
- preserved_flags renamed to PGC_preserved
- PGC_preserved is used only in assign_pages()
v5:
- new patch
---
 xen/common/page_alloc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index 2ec17df9b4..7c135e0bb4 100644
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -157,6 +157,8 @@
 #define PGC_static 0
 #endif
 
+#define PGC_preserved (PGC_extra | PGC_static)
+
 #ifndef PGT_TYPE_INFO_INITIALIZER
 #define PGT_TYPE_INFO_INITIALIZER 0
 #endif
@@ -2362,7 +2364,7 @@ int assign_pages(
 
         for ( i = 0; i < nr; i++ )
         {
-            ASSERT(!(pg[i].count_info & ~(PGC_extra | PGC_static)));
+            ASSERT(!(pg[i].count_info & ~PGC_preserved));
             if ( pg[i].count_info & PGC_extra )
                 extra_pages++;
         }
@@ -2422,7 +2424,7 @@ int assign_pages(
         page_set_owner(&pg[i], d);
         smp_wmb(); /* Domain pointer must be visible before updating refcnt. */
         pg[i].count_info =
-            (pg[i].count_info & (PGC_extra | PGC_static)) | PGC_allocated | 1;
+            (pg[i].count_info & PGC_preserved) | PGC_allocated | 1;
 
         page_list_add_tail(&pg[i], page_to_list(d, &pg[i]));
     }
-- 
2.34.1