1999-06-27 Thomas Bushnell, BSG <tb@mit.edu>

	* vm/vm_resident.c (vm_page_external_count): Define variable.
	(vm_page_grab): New argument `external'.  All callers changed.
	Keep track of number of externally managed pages.  Don't let
	non-privileged threads exceed the externally-managed page limit.
	(vm_page_grab_contiguous_pages): New argument `external'.  All
	callers changed.  Keep track of number of externally managed
	pages.  Don't let non-privileged threads exceed the
	externally-managed page limit.
	(vm_page_convert): New argument `external'.  All callers changed.
	(vm_page_release): New argument `external'.  All callers
	changed. Keep track of number of externally managed pages.
	(vm_page_bootstrap): Initialize M->external.
	* vm/vm_page.h (vm_page_external_limit, vm_page_external_count):
	New variables.
	(struct vm_page): New members `external' and `extcounted'.
	* vm/vm_pageout.c (vm_pageout): Initialize vm_page_external_limit
	and vm_page_external_target.
	(VM_PAGE_EXTERNAL_LIMIT, VM_PAGE_EXTERNAL_TARGET): New macro.
	(vm_pageout_external_target): New variable.
	(vm_pageout_scan): Regard "too many externally managed pages" as a
	reason to keep doing work, but if that's the only reason we're
	doing work, then the only thing we do is schedule cleaning of
	pages.  Help keep track of the number of externally managed pages
	that we care about.

	* vm/vm_pageout.c (VM_PAGEOUT_BURST_WAIT): Reduce to 10ms/page.
	(VM_PAGEOUT_EMPTY_WAIT): Reduce to 75 ms.
	(VM_PAGE_FREE_RESERVED): Increase to 50 pages.
	(VM_PAGEOUT_RESERVED_INTERNAL): Adjust to `(reserve) - 25'.
	(VM_PAGEOUT_RESERVED_REALLY): Adjust to `(reserve) - 40'.

1 files changed, 32 insertions, 15 deletions

diff --git a/vm/vm_resident.c b/vm/vm_resident.c
index eba01570..5014da4d 100644
--- a/vm/vm_resident.c
+++ b/vm/vm_resident.c
@@ -111,6 +111,7 @@ decl_simple_lock_data(,vm_page_queue_free_lock)
 unsigned int	vm_page_free_wanted;
 int		vm_page_free_count;
 int		vm_page_fictitious_count;
+int		vm_page_external_count;
 
 unsigned int	vm_page_free_count_minimum;	/* debugging */
 
@@ -201,6 +202,7 @@ void vm_page_bootstrap(
 	m->active = FALSE;
 	m->laundry = FALSE;
 	m->free = FALSE;
+	m->external = FALSE;
 
 	m->busy = TRUE;
 	m->wanted = FALSE;
@@ -396,7 +398,7 @@ void pmap_startup(
 	 */
 
 	for (i = pages_initialized; i > 0; i--) {
-		vm_page_release(&pages[i - 1]);
+		vm_page_release(&pages[i - 1], FALSE);
 	}
 
 	/*
@@ -449,7 +451,7 @@ void vm_page_create(
 			panic("vm_page_create");
 
 		vm_page_init(m, paddr);
-		vm_page_release(m);
+		vm_page_release(m, FALSE);
 	}
 }
 
@@ -816,11 +818,12 @@ void vm_page_more_fictitious(void)
  */
 
 boolean_t vm_page_convert(
-	register vm_page_t m)
+	register vm_page_t m,
+	boolean_t external)
 {
 	register vm_page_t real_m;
 
-	real_m = vm_page_grab();
+	real_m = vm_page_grab(external);
 	if (real_m == VM_PAGE_NULL)
 		return FALSE;
 
@@ -841,7 +844,8 @@ boolean_t vm_page_convert(
  *	Returns VM_PAGE_NULL if the free list is too small.
  */
 
-vm_page_t vm_page_grab(void)
+vm_page_t vm_page_grab(
+	boolean_t external)
 {
 	register vm_page_t	mem;
 
@@ -849,10 +853,12 @@ vm_page_t vm_page_grab(void)
 
 	/*
 	 *	Only let privileged threads (involved in pageout)
-	 *	dip into the reserved pool.
+	 *	dip into the reserved pool or exceed the limit
+	 *	for externally-managed pages.
 	 */
 
-	if ((vm_page_free_count < vm_page_free_reserved) &&
+	if (((vm_page_free_count < vm_page_free_reserved) ||
+	     (vm_page_external_count >= vm_page_external_limit)) &&
 	    !current_thread()->vm_privilege) {
 		simple_unlock(&vm_page_queue_free_lock);
 		return VM_PAGE_NULL;
@@ -863,9 +869,12 @@ vm_page_t vm_page_grab(void)
 
 	if (--vm_page_free_count < vm_page_free_count_minimum)
 		vm_page_free_count_minimum = vm_page_free_count;
+	if (external)
+		vm_page_external_count++;
 	mem = vm_page_queue_free;
 	vm_page_queue_free = (vm_page_t) mem->pageq.next;
 	mem->free = FALSE;
+	mem->extcounted = mem->external = external;
 	simple_unlock(&vm_page_queue_free_lock);
 
 	/*
@@ -887,9 +896,9 @@ vm_page_t vm_page_grab(void)
 	return mem;
 }
 
-vm_offset_t vm_page_grab_phys_addr(void)
+vm_offset_t vm_page_grab_phys_addr()
 {
-	vm_page_t p = vm_page_grab();
+	vm_page_t p = vm_page_grab(FALSE);
 	if (p == VM_PAGE_NULL)
 		return -1;
 	else
@@ -915,7 +924,8 @@ kern_return_t
 vm_page_grab_contiguous_pages(
 	int		npages,
 	vm_page_t	pages[],
-	natural_t	*bits)
+	natural_t	*bits,
+	boolean_t	external)
 {
 	register int	first_set;
 	int		size, alloc_size;
@@ -959,7 +969,8 @@ vm_page_grab_contiguous_pages(
 	 *	Do not dip into the reserved pool.
 	 */
 
-	if (vm_page_free_count < vm_page_free_reserved) {
+	if ((vm_page_free_count < vm_page_free_reserved)
+	    || (vm_page_external_count >= vm_page_external_limit)) {
 		simple_unlock(&vm_page_queue_free_lock);
 		return KERN_RESOURCE_SHORTAGE;
 	}
@@ -1063,7 +1074,8 @@ found_em:
 	vm_page_free_count -= npages;
 	if (vm_page_free_count < vm_page_free_count_minimum)
 		vm_page_free_count_minimum = vm_page_free_count;
-
+	if (external)
+		vm_page_external_count += npages;
 	{
 	    register vm_offset_t	first_phys, last_phys;
 
@@ -1087,6 +1099,7 @@ found_em:
 			prevmem->pageq.next = mem->pageq.next;
 		    pages[(addr - first_phys) >> PAGE_SHIFT] = mem;
 		    mem->free = FALSE;
+		    mem->extcounted = mem->external = external;
 		    /*
 		     * Got them all ?
 		     */
@@ -1131,7 +1144,8 @@ out:
  */
 
 void vm_page_release(
-	register vm_page_t	mem)
+	register vm_page_t	mem,
+	boolean_t external)
 {
 	simple_lock(&vm_page_queue_free_lock);
 	if (mem->free)
@@ -1140,6 +1154,8 @@ void vm_page_release(
 	mem->pageq.next = (queue_entry_t) vm_page_queue_free;
 	vm_page_queue_free = mem;
 	vm_page_free_count++;
+	if (external)
+		vm_page_external_count--;
 
 	/*
 	 *	Check if we should wake up someone waiting for page.
@@ -1225,7 +1241,7 @@ vm_page_t vm_page_alloc(
 {
 	register vm_page_t	mem;
 
-	mem = vm_page_grab();
+	mem = vm_page_grab(!object->internal);
 	if (mem == VM_PAGE_NULL)
 		return VM_PAGE_NULL;
 
@@ -1280,8 +1296,9 @@ void vm_page_free(
 		mem->fictitious = TRUE;
 		vm_page_release_fictitious(mem);
 	} else {
+		int external = mem->external && mem->extcounted;
 		vm_page_init(mem, mem->phys_addr);
-		vm_page_release(mem);
+		vm_page_release(mem, external);
 	}
 }