Integrated VM system improvements/fixes from FreeBSD-1.1.5.

sys/vm/vm_glue.c

@@ -59,7 +59,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id$
+ * $Id: vm_glue.c,v 1.3 1994/08/02 07:55:19 davidg Exp $
  */
 
 #include <sys/param.h>
@@ -109,19 +109,16 @@ useracc(addr, len, rw)
 	vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE;
 
 	/*
-	 * XXX - specially disallow access to user page tables - they are
-	 * in the map.
-	 *
-	 * XXX - don't specially disallow access to the user area - treat
-	 * it as incorrectly as elsewhere.
+	 * XXX - check separately to disallow access to user area and user
+	 * page tables - they are in the map.
 	 *
 	 * XXX - VM_MAXUSER_ADDRESS is an end address, not a max.  It was
-	 * only used (as an end address) in trap.c.  Use it as an end
-	 * address here too.
+	 * once only used (as an end address) in trap.c.  Use it as an end
+	 * address here too.  This bogusness has spread.  I just fixed
+	 * where it was used as a max in vm_mmap.c.
 	 */
-	if ((vm_offset_t) addr >= VM_MAXUSER_ADDRESS 
-	    || (vm_offset_t) addr + len > VM_MAXUSER_ADDRESS
-	    || (vm_offset_t) addr + len <= (vm_offset_t) addr) {
+	if ((vm_offset_t) addr + len > /* XXX */ VM_MAXUSER_ADDRESS
+	    || (vm_offset_t) addr + len < (vm_offset_t) addr) {
 		return (FALSE);
 	}
 
@@ -276,23 +273,24 @@ void
 vm_init_limits(p)
 	register struct proc *p;
 {
-	int tmp;
+	int rss_limit;
 
 	/*
 	 * Set up the initial limits on process VM.
-	 * Set the maximum resident set size to be all
-	 * of (reasonably) available memory.  This causes
-	 * any single, large process to start random page
-	 * replacement once it fills memory.
+	 * Set the maximum resident set size to be half
+	 * of (reasonably) available memory.  Since this
+	 * is a soft limit, it comes into effect only
+	 * when the system is out of memory - half of
+	 * main memory helps to favor smaller processes,
+	 * and reduces thrashing of the object cache.
 	 */
         p->p_rlimit[RLIMIT_STACK].rlim_cur = DFLSSIZ;
         p->p_rlimit[RLIMIT_STACK].rlim_max = MAXSSIZ;
         p->p_rlimit[RLIMIT_DATA].rlim_cur = DFLDSIZ;
         p->p_rlimit[RLIMIT_DATA].rlim_max = MAXDSIZ;
-	tmp = ((2 * cnt.v_free_count) / 3) - 32;
-	if (cnt.v_free_count < 512)
-		tmp = cnt.v_free_count;
-	p->p_rlimit[RLIMIT_RSS].rlim_cur = ptoa(tmp);
+	/* limit the limit to no less than 128K */ 
+	rss_limit = max(cnt.v_free_count / 2, 32);
+	p->p_rlimit[RLIMIT_RSS].rlim_cur = ptoa(rss_limit);
 	p->p_rlimit[RLIMIT_RSS].rlim_max = RLIM_INFINITY;
 }
 

sys/vm/vm_mmap.c

@@ -38,7 +38,7 @@
  * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
  *
  *	@(#)vm_mmap.c	8.4 (Berkeley) 1/12/94
- * $Id$
+ * $Id: vm_mmap.c,v 1.3 1994/08/02 07:55:28 davidg Exp $
  */
 
 /*
@@ -216,13 +216,13 @@ mmap(p, uap, retval)
 	 * Note that VM_*_ADDRESS are not constants due to casts (argh).
 	 */
 	if (flags & MAP_FIXED) {
-		if (VM_MAXUSER_ADDRESS > 0 && addr + size >= VM_MAXUSER_ADDRESS)
+		if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
 			return (EINVAL);
 #ifndef i386
 		if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
 			return (EINVAL);
 #endif
-		if (addr > addr + size)
+		if (addr + size < addr)
 			return (EINVAL);
 	}
 	/*
@@ -401,13 +401,13 @@ munmap(p, uap, retval)
 	 * Check for illegal addresses.  Watch out for address wrap...
 	 * Note that VM_*_ADDRESS are not constants due to casts (argh).
 	 */
-	if (VM_MAXUSER_ADDRESS > 0 && addr + size >= VM_MAXUSER_ADDRESS)
+	if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
 		return (EINVAL);
 #ifndef i386
 	if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
 		return (EINVAL);
 #endif
-	if (addr > addr + size)
+	if (addr + size < addr)
 		return (EINVAL);
 	map = &p->p_vmspace->vm_map;
 	/*

sys/vm/vm_page.h

@@ -61,7 +61,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id$
+ * $Id: vm_page.h,v 1.3 1994/08/02 07:55:32 davidg Exp $
  */
 
 /*
@@ -132,6 +132,7 @@ struct vm_page {
 #define	PG_FAKE		0x0200		/* page is placeholder for pagein (O) */
 #define	PG_FILLED	0x0400		/* client flag to set when filled */
 #define	PG_DIRTY	0x0800		/* client flag to set when dirty */
+#define PG_REFERENCED	0x1000		/* page has been referenced */
 #define	PG_PAGEROWNED	0x4000		/* DEBUG: async paging op in progress */
 #define	PG_PTPAGE	0x8000		/* DEBUG: is a user page table page */
 

sys/vm/vm_pageout.c

@@ -65,7 +65,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id: vm_pageout.c,v 1.4 1994/08/01 11:25:45 davidg Exp $
+ * $Id: vm_pageout.c,v 1.5 1994/08/02 07:55:33 davidg Exp $
  */
 
 /*
@@ -108,6 +108,7 @@ extern int swap_pager_ready();
 #define LOWATER ((2048*1024)/NBPG)
 
 #define VM_PAGEOUT_PAGE_COUNT 8
+int vm_pageout_page_count = VM_PAGEOUT_PAGE_COUNT;
 static vm_offset_t vm_space_needed;
 int vm_pageout_req_do_stats;
 
@@ -190,7 +191,7 @@ vm_pageout_clean(m, sync)
 	ms[0] = m;
 
 	if( pager = object->pager) {
-		for(i=1;i<VM_PAGEOUT_PAGE_COUNT;i++) {
+		for(i=1;i<vm_pageout_page_count;i++) {
 			if( ms[i] = vm_page_lookup( object, offset+i*NBPG)) {
 				if((((ms[i]->flags & (PG_CLEAN|PG_INACTIVE|PG_BUSY)) == PG_INACTIVE)
 					|| (( ms[i]->flags & PG_CLEAN) == 0 && sync == VM_PAGEOUT_FORCE))
@@ -619,7 +620,7 @@ vm_pageout_scan()
 			/*
 			 * if the next page has been re-activated, start scanning again
 			 */
-			if (next && (next->flags & PG_INACTIVE) == 0)
+			if (!next || (next->flags & PG_INACTIVE) == 0)
 				goto rescan1;
 		} else if (pmap_is_referenced(VM_PAGE_TO_PHYS(m))) {
 			pmap_clear_reference(VM_PAGE_TO_PHYS(m));