This commit is meant to solve a couple of VM system problems or

performance issues.

	1) The pmap module has had too many inlines, and so the
	   object file is simply bigger than it needs to be.
	   Some common code is also merged into subroutines.
	2) Removal of some *evil* PHYS_TO_VM_PAGE macro calls.
	   Unfortunately, a few have needed to be added also.
	   The removal caused the need for more vm_page_lookups.
	   I added lookup hints to minimize the need for the
	   page table lookup operations.
	3) Removal of some bogus performance improvements, that
	   mostly made the code more complex (tracking individual
	   page table page updates unnecessarily).  Those improvements
	   actually hurt 386 processors perf (not that people who
	   worry about perf use 386 processors anymore :-)).
	4) Changed pv queue manipulations/structures to be TAILQ's.
	5) The pv queue code has had some performance problems since
	   day one.  Some significant scalability issues are resolved
	   by threading the pv entries from the pmap AND the physical
	   address instead of just the physical address.  This makes
	   certain pmap operations run much faster.  This does
	   not affect most micro-benchmarks, but should help loaded system
	   performance *significantly*.  DG helped and came up with most
	   of the solution for this one.
	6) Most if not all pmap bit operations follow the pattern:
		pmap_test_bit();
		pmap_clear_bit();
	   That made for twice the necessary pv list traversal.   The
	   pmap interface now supports only pmap_tc_bit type operations:
	   pmap_[test/clear]_modified, pmap_[test/clear]_referenced.
	   Additionally, the modified routine now takes a vm_page_t arg
	   instead of a phys address.  This eliminates a PHYS_TO_VM_PAGE
	   operation.
	7) Several rewrites of routines that contain redundant code to
	   use common routines, so that there is a greater likelihood of
	   keeping the cache footprint smaller.

1 files changed, 177 insertions, 27 deletions

diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c
index 697baf6..ff0e79c 100644
--- a/sys/vm/vm_mmap.c
+++ b/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: vm_mmap.c,v 1.43 1996/05/19 07:36:49 dyson Exp $
+ * $Id: vm_mmap.c,v 1.44 1996/05/31 00:38:00 dyson Exp $
  */
 
 /*
@@ -72,6 +72,7 @@
 #include <vm/vm_extern.h>
 #include <vm/vm_kern.h>
 #include <vm/vm_page.h>
+#include <vm/loadaout.h>
 
 #ifndef _SYS_SYSPROTO_H_
 struct sbrk_args {
@@ -689,10 +690,10 @@ mincore(p, uap, retval)
 				if (m) {
 					mincoreinfo = MINCORE_INCORE;
 					if (m->dirty ||
-						pmap_is_modified(VM_PAGE_TO_PHYS(m)))
+						pmap_tc_modified(m))
 						mincoreinfo |= MINCORE_MODIFIED_OTHER;
 					if ((m->flags & PG_REFERENCED) ||
-						pmap_is_referenced(VM_PAGE_TO_PHYS(m)))
+						pmap_tc_referenced(VM_PAGE_TO_PHYS(m)))
 						mincoreinfo |= MINCORE_REFERENCED_OTHER;
 				}
 			}
@@ -844,7 +845,7 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
 	vm_ooffset_t foff;
 {
 	boolean_t fitit;
-	vm_object_t object, object2;
+	vm_object_t object;
 	struct vnode *vp = NULL;
 	objtype_t type;
 	int rv = KERN_SUCCESS;
@@ -916,29 +917,13 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
 		flags |= MAP_SHARED;
 	}
 
-	object2 = NULL;
 	docow = 0;
 	if ((flags & (MAP_ANON|MAP_SHARED)) == 0) {
-		docow = MAP_COPY_ON_WRITE;
-		if (objsize < size) {
-			object2 = vm_object_allocate( OBJT_DEFAULT,
-				OFF_TO_IDX(size - (foff & ~PAGE_MASK)));
-			object2->backing_object = object;
-			object2->backing_object_offset = foff;
-			TAILQ_INSERT_TAIL(&object->shadow_head,
-				object2, shadow_list);
-			++object->shadow_count;
-		} else {
-			docow |= MAP_COPY_NEEDED;
-		}
+		docow = MAP_COPY_ON_WRITE|MAP_COPY_NEEDED;
 	}
 
-	if (object2)
-		rv = vm_map_find(map, object2, 0, addr, size, fitit,
-			prot, maxprot, docow);
-	else
-		rv = vm_map_find(map, object, foff, addr, size, fitit,
-			prot, maxprot, docow);
+	rv = vm_map_find(map, object, foff, addr, size, fitit,
+		prot, maxprot, docow);
 
 
 	if (rv != KERN_SUCCESS) {
@@ -947,10 +932,7 @@ vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
 		 * object if it's an unnamed anonymous mapping
 		 * or named anonymous without other references.
 		 */
-		if (object2)
-			vm_object_deallocate(object2);
-		else
-			vm_object_deallocate(object);
+		vm_object_deallocate(object);
 		goto out;
 	}
 
@@ -985,3 +967,171 @@ out:
 		return (EINVAL);
 	}
 }
+
+#ifdef notyet
+/*
+ * Efficient mapping of a .text+.data+.bss object
+ */
+int
+vm_mapaout(map, baseaddr, vp, foff, textsize, datasize, bsssize, addr)
+	vm_map_t map;
+	vm_offset_t baseaddr;
+	struct vnode *vp;
+	vm_ooffset_t foff;
+	register vm_size_t textsize, datasize, bsssize;
+	vm_offset_t *addr;
+{
+	vm_object_t object;
+	int rv;
+	vm_pindex_t objpsize;
+	struct proc *p = curproc;
+
+	vm_size_t totalsize;
+	vm_size_t textend;
+	struct vattr vat;
+	int error;
+	
+	textsize = round_page(textsize);
+	datasize = round_page(datasize);
+	bsssize = round_page(bsssize);
+	totalsize = textsize + datasize + bsssize;
+
+	vm_map_lock(map);
+	/*
+	 * If baseaddr == -1, then we need to search for space.  Otherwise,
+	 * we need to be loaded into a certain spot.
+	 */
+	if (baseaddr != (vm_offset_t) -1) {
+		if (vm_map_findspace(map, baseaddr, totalsize, addr)) {
+			goto outnomem;
+		}
+
+		if(*addr != baseaddr) {
+			goto outnomem;
+		}
+	} else {
+		baseaddr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
+		if (vm_map_findspace(map, baseaddr, totalsize, addr)) {
+			goto outnomem;
+		}
+	}
+
+	if (foff & PAGE_MASK) {
+		vm_map_unlock(map);
+		return EINVAL;
+	}
+
+	/*
+	 * get the object size to allocate
+	 */
+	error = VOP_GETATTR(vp, &vat, p->p_ucred, p);
+	if (error) {
+		vm_map_unlock(map);
+		return error;
+	}
+	objpsize = OFF_TO_IDX(round_page(vat.va_size));
+
+	/*
+	 * Alloc/reference the object
+	 */
+	object = vm_pager_allocate(OBJT_VNODE, vp,
+		   objpsize, VM_PROT_ALL, foff);
+	if (object == NULL) {
+		goto outnomem;
+	}
+
+	/*
+	 * Insert .text into the map
+	 */
+	textend = *addr + textsize;
+	rv = vm_map_insert(map, object, foff,
+		*addr, textend,
+		VM_PROT_READ|VM_PROT_EXECUTE, VM_PROT_ALL,
+		MAP_COPY_ON_WRITE|MAP_COPY_NEEDED);
+	if (rv != KERN_SUCCESS) {
+		vm_object_deallocate(object);
+		goto out;
+	}
+	
+	/*
+	 * Insert .data into the map, if there is any to map.
+	 */
+	if (datasize != 0) {
+		object->ref_count++;
+		rv = vm_map_insert(map, object, foff + textsize,
+			textend, textend + datasize,
+			VM_PROT_ALL, VM_PROT_ALL,
+			MAP_COPY_ON_WRITE|MAP_COPY_NEEDED);
+		if (rv != KERN_SUCCESS) {
+			--object->ref_count;
+			vm_map_delete(map, *addr, textend);
+			goto out;
+		}
+	}
+
+	/*
+	 * Preload the page tables
+	 */
+	pmap_object_init_pt(map->pmap, *addr,
+		object, (vm_pindex_t) OFF_TO_IDX(foff),
+		textsize + datasize, 1);
+
+	/*
+	 * Get the space for bss.
+	 */
+	if (bsssize != 0) {
+		rv = vm_map_insert(map, NULL, 0,
+			textend + datasize,
+			*addr + totalsize,
+			VM_PROT_ALL, VM_PROT_ALL, 0);
+	}
+	if (rv != KERN_SUCCESS) {
+		vm_map_delete(map, *addr, textend + datasize + bsssize);
+	}
+
+out:
+	vm_map_unlock(map);
+	switch (rv) {
+	case KERN_SUCCESS:
+		return 0;
+	case KERN_INVALID_ADDRESS:
+	case KERN_NO_SPACE:
+		return ENOMEM;
+	case KERN_PROTECTION_FAILURE:
+		return EACCES;
+	default:
+		return EINVAL;
+	}
+outnomem:
+	vm_map_unlock(map);
+	return ENOMEM;
+}
+
+
+int
+mapaout(struct proc *p, struct mapaout_args *uap, int *retval)
+{
+
+	register struct filedesc *fdp = p->p_fd;
+	struct file *fp;
+	struct vnode *vp;
+	int rtval;
+
+	if (((unsigned) uap->fd) >= fdp->fd_nfiles ||
+	    (fp = fdp->fd_ofiles[uap->fd]) == NULL)
+		return (EBADF);
+	if (fp->f_type != DTYPE_VNODE)
+		return (EINVAL);
+
+	vp = (struct vnode *) fp->f_data;
+	if ((vp->v_type != VREG) && (vp->v_type != VCHR))
+		return (EINVAL);
+
+	rtval = vm_mapaout( &p->p_vmspace->vm_map,
+		uap->addr, vp, uap->offset,
+		uap->textsize, uap->datasize, uap->bsssize,
+		(vm_offset_t *)retval);
+
+	return rtval;
+}
+#endif