xen/x86-domain-shutdown-latency.patch

71 lines
2.5 KiB
Diff

Index: xen-3.2.1-testing/xen/arch/x86/domain.c
===================================================================
--- xen-3.2.1-testing.orig/xen/arch/x86/domain.c
+++ xen-3.2.1-testing/xen/arch/x86/domain.c
@@ -1709,6 +1709,23 @@ static int relinquish_memory(
if ( test_and_clear_bit(_PGC_allocated, &page->count_info) )
put_page(page);
+ y = page->u.inuse.type_info;
+
+ /*
+ * Forcibly drop reference counts of page tables above top most (which
+ * were skipped to prevent long latencies due to deep recursion - see
+ * the special treatment in free_lX_table()).
+ */
+ if ( type < PGT_root_page_table &&
+ unlikely(((y + PGT_type_mask) &
+ (PGT_type_mask|PGT_validated)) == type) ) {
+ BUG_ON((y & PGT_count_mask) >= (page->count_info & PGC_count_mask));
+ while ( y & PGT_count_mask ) {
+ put_page_and_type(page);
+ y = page->u.inuse.type_info;
+ }
+ }
+
/*
* Forcibly invalidate top-most, still valid page tables at this point
* to break circular 'linear page table' references. This is okay
@@ -1716,7 +1733,6 @@ static int relinquish_memory(
* is now dead. Thus top-most valid tables are not in use so a non-zero
* count means circular reference.
*/
- y = page->u.inuse.type_info;
for ( ; ; )
{
x = y;
@@ -1880,6 +1896,9 @@ int domain_relinquish_resources(struct d
/* fallthrough */
case RELMEM_done:
+ ret = relinquish_memory(d, &d->page_list, PGT_l1_page_table);
+ if ( ret )
+ return ret;
break;
default:
Index: xen-3.2.1-testing/xen/arch/x86/mm.c
===================================================================
--- xen-3.2.1-testing.orig/xen/arch/x86/mm.c
+++ xen-3.2.1-testing/xen/arch/x86/mm.c
@@ -1305,6 +1305,9 @@ static void free_l3_table(struct page_in
l3_pgentry_t *pl3e;
int i;
+ if(d->arch.relmem == RELMEM_dom_l3)
+ return;
+
pl3e = map_domain_page(pfn);
for ( i = 0; i < L3_PAGETABLE_ENTRIES; i++ )
@@ -1328,6 +1331,9 @@ static void free_l4_table(struct page_in
l4_pgentry_t *pl4e = page_to_virt(page);
int i;
+ if(d->arch.relmem == RELMEM_dom_l4)
+ return;
+
for ( i = 0; i < L4_PAGETABLE_ENTRIES; i++ )
if ( is_guest_l4_slot(d, i) )
put_page_from_l4e(pl4e[i], pfn);