@@ -919,11 +919,50 @@ static int reserve_offlined_page(struct page_info *head)
return count;
}
+/* Returns new buddy head. */
+static struct page_info *
+merge_and_free_buddy(struct page_info *pg, unsigned int node,
+ unsigned int zone, unsigned int order)
+{
+ ASSERT(spin_is_locked(&heap_lock));
+
+ /* Merge chunks as far as possible. */
+ while ( order < MAX_ORDER )
+ {
+ unsigned long mask = 1UL << order;
+ struct page_info *buddy;
+
+ if ( (page_to_mfn(pg) & mask) )
+ buddy = pg - mask; /* Merge with predecessor block. */
+ else
+ buddy = pg + mask; /* Merge with successor block. */
+
+ if ( !mfn_valid(_mfn(page_to_mfn(buddy))) ||
+ !page_state_is(buddy, free) ||
+ (PFN_ORDER(buddy) != order) ||
+ (phys_to_nid(page_to_maddr(buddy)) != node) )
+ break;
+
+ page_list_del(buddy, &heap(node, zone, order));
+
+ /* Adjust current buddy head if we merged backwards. */
+ if ( buddy < pg )
+ pg = buddy;
+
+ order++;
+ }
+
+ PFN_ORDER(pg) = order;
+ page_list_add_tail(pg, &heap(node, zone, order));
+
+ return pg;
+}
+
/* Free 2^@order set of pages. */
static void free_heap_pages(
struct page_info *pg, unsigned int order)
{
- unsigned long mask, mfn = page_to_mfn(pg);
+ unsigned long mfn = page_to_mfn(pg);
unsigned int i, node = phys_to_nid(page_to_maddr(pg)), tainted = 0;
unsigned int zone = page_to_zone(pg);
@@ -970,38 +1009,7 @@ static void free_heap_pages(
midsize_alloc_zone_pages = max(
midsize_alloc_zone_pages, total_avail_pages / MIDSIZE_ALLOC_FRAC);
- /* Merge chunks as far as possible. */
- while ( order < MAX_ORDER )
- {
- mask = 1UL << order;
-
- if ( (page_to_mfn(pg) & mask) )
- {
- /* Merge with predecessor block? */
- if ( !mfn_valid(_mfn(page_to_mfn(pg-mask))) ||
- !page_state_is(pg-mask, free) ||
- (PFN_ORDER(pg-mask) != order) ||
- (phys_to_nid(page_to_maddr(pg-mask)) != node) )
- break;
- pg -= mask;
- page_list_del(pg, &heap(node, zone, order));
- }
- else
- {
- /* Merge with successor block? */
- if ( !mfn_valid(_mfn(page_to_mfn(pg+mask))) ||
- !page_state_is(pg+mask, free) ||
- (PFN_ORDER(pg+mask) != order) ||
- (phys_to_nid(page_to_maddr(pg+mask)) != node) )
- break;
- page_list_del(pg + mask, &heap(node, zone, order));
- }
-
- order++;
- }
-
- PFN_ORDER(pg) = order;
- page_list_add_tail(pg, &heap(node, zone, order));
+ pg = merge_and_free_buddy(pg, node, zone, order);
if ( tainted )
reserve_offlined_page(pg);
This is needed for subsequent changes to memory scrubbing. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> --- Changes in v3: * Simplify merge_and_free_buddy() (and drop can_merge()) xen/common/page_alloc.c | 74 ++++++++++++++++++++++++++--------------------- 1 files changed, 41 insertions(+), 33 deletions(-)