From b28c6ddbbcc319ef6379eaa4b4b52efc3f03959f Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Thu, 20 May 2010 16:21:19 +0000 Subject: MFC r207306 Change vm_object_madvise() so that it checks whether the page is invalid or unmanaged before acquiring the page queues lock. Neither of these tests require that lock. Moreover, a better way of testing if the page is unmanaged is to test the type of vm object. This avoids a pointless vm_page_lookup(). --- sys/vm/vm_object.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) (limited to 'sys/vm') diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c index 7e4dbc853507..c25ab775794f 100644 --- a/sys/vm/vm_object.c +++ b/sys/vm/vm_object.c @@ -1162,7 +1162,8 @@ shadowlookup: (tobject->flags & OBJ_ONEMAPPING) == 0) { goto unlock_tobject; } - } + } else if (tobject->type == OBJT_PHYS) + goto unlock_tobject; m = vm_page_lookup(tobject, tpindex); if (m == NULL && advise == MADV_WILLNEED) { /* @@ -1189,18 +1190,13 @@ shadowlookup: VM_OBJECT_UNLOCK(tobject); tobject = backing_object; goto shadowlookup; - } + } else if (m->valid != VM_PAGE_BITS_ALL) + goto unlock_tobject; /* - * If the page is busy or not in a normal active state, - * we skip it. If the page is not managed there are no - * page queues to mess with. Things can break if we mess - * with pages in any of the below states. + * If the page is not in a normal state, skip it. */ vm_page_lock_queues(); - if (m->hold_count || - m->wire_count || - (m->flags & PG_UNMANAGED) || - m->valid != VM_PAGE_BITS_ALL) { + if (m->hold_count != 0 || m->wire_count != 0) { vm_page_unlock_queues(); goto unlock_tobject; } -- cgit v1.3