svn commit: r324389 - stable/11/sys/vm

[Alan Cox]

Author: alc
Date: Sat Oct  7 18:08:37 2017
New Revision: 324389
URL: https://svnweb.freebsd.org/changeset/base/324389

Log:
  MFC r320980,321377
    Generalize vm_page_ps_is_valid() to support testing other predicates on
    the (super)page, renaming the function to vm_page_ps_test().
  
    In vm_page_ps_test(), always check that the base pages within the specified
    superpage all belong to the same object.  To date, that check has not been
    needed, but upcoming changes require it.

Modified:
  stable/11/sys/vm/vm_map.c
  stable/11/sys/vm/vm_page.c
  stable/11/sys/vm/vm_page.h
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/vm/vm_map.c
==============================================================================
--- stable/11/sys/vm/vm_map.c	Sat Oct  7 17:40:31 2017	(r324388)
+++ stable/11/sys/vm/vm_map.c	Sat Oct  7 18:08:37 2017	(r324389)
@@ -1962,7 +1962,7 @@ vm_map_pmap_enter(vm_map_t map, vm_offset_t addr, vm_p
 			    (pagesizes[p->psind] - 1)) == 0) {
 				mask = atop(pagesizes[p->psind]) - 1;
 				if (tmpidx + mask < psize &&
-				    vm_page_ps_is_valid(p)) {
+				    vm_page_ps_test(p, PS_ALL_VALID, NULL)) {
 					p += mask;
 					threshold += mask;
 				}

Modified: stable/11/sys/vm/vm_page.c
==============================================================================
--- stable/11/sys/vm/vm_page.c	Sat Oct  7 17:40:31 2017	(r324388)
+++ stable/11/sys/vm/vm_page.c	Sat Oct  7 18:08:37 2017	(r324389)
@@ -3612,16 +3612,17 @@ vm_page_is_valid(vm_page_t m, int base, int size)
 }
 
 /*
- *	vm_page_ps_is_valid:
- *
- *	Returns TRUE if the entire (super)page is valid and FALSE otherwise.
+ * Returns true if all of the specified predicates are true for the entire
+ * (super)page and false otherwise.
  */
-boolean_t
-vm_page_ps_is_valid(vm_page_t m)
+bool
+vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m)
 {
+	vm_object_t object;
 	int i, npages;
 
-	VM_OBJECT_ASSERT_LOCKED(m->object);
+	object = m->object;
+	VM_OBJECT_ASSERT_LOCKED(object);
 	npages = atop(pagesizes[m->psind]);
 
 	/*
@@ -3630,10 +3631,28 @@ vm_page_ps_is_valid(vm_page_t m)
 	 * occupy adjacent entries in vm_page_array[].
 	 */
 	for (i = 0; i < npages; i++) {
-		if (m[i].valid != VM_PAGE_BITS_ALL)
-			return (FALSE);
+		/* Always test object consistency, including "skip_m". */
+		if (m[i].object != object)
+			return (false);
+		if (&m[i] == skip_m)
+			continue;
+		if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i]))
+			return (false);
+		if ((flags & PS_ALL_DIRTY) != 0) {
+			/*
+			 * Calling vm_page_test_dirty() or pmap_is_modified()
+			 * might stop this case from spuriously returning
+			 * "false".  However, that would require a write lock
+			 * on the object containing "m[i]".
+			 */
+			if (m[i].dirty != VM_PAGE_BITS_ALL)
+				return (false);
+		}
+		if ((flags & PS_ALL_VALID) != 0 &&
+		    m[i].valid != VM_PAGE_BITS_ALL)
+			return (false);
 	}
-	return (TRUE);
+	return (true);
 }
 
 /*

Modified: stable/11/sys/vm/vm_page.h
==============================================================================
--- stable/11/sys/vm/vm_page.h	Sat Oct  7 17:40:31 2017	(r324388)
+++ stable/11/sys/vm/vm_page.h	Sat Oct  7 18:08:37 2017	(r324389)
@@ -440,6 +440,18 @@ malloc2vm_flags(int malloc_flags)
 }
 #endif
 
+/*
+ * Predicates supported by vm_page_ps_test():
+ *
+ *	PS_ALL_DIRTY is true only if the entire (super)page is dirty.
+ *	However, it can be spuriously false when the (super)page has become
+ *	dirty in the pmap but that information has not been propagated to the
+ *	machine-independent layer.
+ */
+#define	PS_ALL_DIRTY	0x1
+#define	PS_ALL_VALID	0x2
+#define	PS_NONE_BUSY	0x4
+
 void vm_page_busy_downgrade(vm_page_t m);
 void vm_page_busy_sleep(vm_page_t m, const char *msg, bool nonshared);
 void vm_page_flash(vm_page_t m);
@@ -475,7 +487,7 @@ vm_page_t vm_page_next(vm_page_t m);
 int vm_page_pa_tryrelock(pmap_t, vm_paddr_t, vm_paddr_t *);
 struct vm_pagequeue *vm_page_pagequeue(vm_page_t m);
 vm_page_t vm_page_prev(vm_page_t m);
-boolean_t vm_page_ps_is_valid(vm_page_t m);
+bool vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m);
 void vm_page_putfake(vm_page_t m);
 void vm_page_readahead_finish(vm_page_t m);
 bool vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low,