diff options
Diffstat (limited to 'sys/vm/vm_object.c')
| -rw-r--r-- | sys/vm/vm_object.c | 30 |
1 files changed, 12 insertions, 18 deletions
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c index bb95ec2ef4e9..250f7276a69d 100644 --- a/sys/vm/vm_object.c +++ b/sys/vm/vm_object.c @@ -61,7 +61,7 @@ * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. * - * $Id: vm_object.c,v 1.147 1999/02/08 05:15:54 dillon Exp $ + * $Id: vm_object.c,v 1.148 1999/02/08 19:00:15 dillon Exp $ */ /* @@ -762,8 +762,8 @@ vm_object_madvise(object, pindex, count, advise) end = pindex + count; /* - * MADV_FREE special case - free any swap backing store (as well - * as resident pages later on). + * MADV_FREE special case - free any swap backing store now, + * whether or not resident pages can be found later. */ if (advise == MADV_FREE) { @@ -835,24 +835,18 @@ shadowlookup: vm_page_deactivate(m); } else if (advise == MADV_FREE) { /* - * If MADV_FREE_FORCE_FREE is defined, we attempt to - * immediately free the page. Otherwise we just - * destroy any swap backing store, mark it clean, - * and stuff it into the cache. + * Mark the page clean. This will allow the page + * to be freed up by the system. However, such pages + * are often reused quickly by malloc()/free() + * so we do not do anything that would cause + * a page fault if we can help it. + * + * Specifically, we do not try to actually free + * the page now nor do we try to put it in the + * cache (which would cause a page fault on reuse). */ pmap_clear_modify(VM_PAGE_TO_PHYS(m)); m->dirty = 0; - -#ifdef MADV_FREE_FORCE_FREE - if (tobject->resident_page_count > 1) { - vm_page_busy(m); - vm_page_protect(m, VM_PROT_NONE); - vm_page_free(m); - } else -#endif - { - vm_page_cache(m); - } } } } |