svn commit: r186633 - head/sys/vm

[Alan Cox]

Author: alc
Date: Wed Dec 31 05:44:05 2008
New Revision: 186633
URL: http://svn.freebsd.org/changeset/base/186633

Log:
  Update or eliminate some stale comments.

Modified:
  head/sys/vm/vm_map.c
  head/sys/vm/vm_map.h

Modified: head/sys/vm/vm_map.c
==============================================================================
--- head/sys/vm/vm_map.c	Wed Dec 31 05:44:00 2008	(r186632)
+++ head/sys/vm/vm_map.c	Wed Dec 31 05:44:05 2008	(r186633)
@@ -100,7 +100,8 @@ __FBSDID("$FreeBSD$");
  *	Synchronization is required prior to most operations.
  *
  *	Maps consist of an ordered doubly-linked list of simple
- *	entries; a single hint is used to speed up lookups.
+ *	entries; a self-adjusting binary search tree of these
+ *	entries is used to speed up lookups.
  *
  *	Since portions of maps are specified by start/end addresses,
  *	which may not align with existing map entries, all
@@ -1629,7 +1630,7 @@ vm_map_protect(vm_map_t map, vm_offset_t
 
 		/*
 		 * Update physical map if necessary. Worry about copy-on-write
-		 * here -- CHECK THIS XXX
+		 * here.
 		 */
 		if (current->protection != old_prot) {
 #define MASK(entry)	(((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \
@@ -1806,7 +1807,7 @@ vm_map_madvise(
  *	Sets the inheritance of the specified address
  *	range in the target map.  Inheritance
  *	affects how the map will be shared with
- *	child maps at the time of vm_map_fork.
+ *	child maps at the time of vmspace_fork.
  */
 int
 vm_map_inherit(vm_map_t map, vm_offset_t start, vm_offset_t end,

Modified: head/sys/vm/vm_map.h
==============================================================================
--- head/sys/vm/vm_map.h	Wed Dec 31 05:44:00 2008	(r186632)
+++ head/sys/vm/vm_map.h	Wed Dec 31 05:44:05 2008	(r186633)
@@ -109,7 +109,6 @@ struct vm_map_entry {
 	union vm_map_object object;	/* object I point to */
 	vm_ooffset_t offset;		/* offset into object */
 	vm_eflags_t eflags;		/* map entry flags */
-	/* Only in task maps: */
 	vm_prot_t protection;		/* protection code */
 	vm_prot_t max_protection;	/* maximum protection */
 	vm_inherit_t inheritance;	/* inheritance */
@@ -168,13 +167,6 @@ vm_map_entry_system_wired_count(vm_map_e
  *	Tarjan's top-down splay algorithm is employed to control
  *	height imbalance in the binary search tree.
  *
- *	Note: the lock structure cannot be the first element of vm_map
- *	because this can result in a running lockup between two or more
- *	system processes trying to kmem_alloc_wait() due to kmem_alloc_wait()
- *	and free tsleep/waking up 'map' and the underlying lockmgr also
- *	sleeping and waking up on 'map'.  The lockup occurs when the map fills
- *	up.  The 'exec' map, for example.
- *
  * List of locks
  *	(c)	const until freed
  */
@@ -186,7 +178,7 @@ struct vm_map {
 	vm_size_t size;			/* virtual size */
 	u_int timestamp;		/* Version number */
 	u_char needs_wakeup;
-	u_char system_map;		/* Am I a system map? */
+	u_char system_map;		/* (c) Am I a system map? */
 	vm_flags_t flags;		/* flags for this vm_map */
 	vm_map_entry_t root;		/* Root of a binary search tree */
 	pmap_t pmap;			/* (c) Physical map */