Optimize vmmeter locking.

In particular:
- Add an explicative table for locking of struct vmmeter members
- Apply new rules for some of those members
- Remove some unuseful comments

Heavily reviewed by: alc, bde, jeff
Approved by: jeff (mentor)

1 files changed, 2 insertions, 7 deletions

diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index 263ee05..e1ef640 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -1045,7 +1045,7 @@ vm_page_activate(vm_page_t m)
 	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
 	if (VM_PAGE_GETKNOWNQUEUE2(m) != PQ_ACTIVE) {
 		if (VM_PAGE_INQUEUE1(m, PQ_CACHE))
-			PCPU_INC(cnt.v_reactivated);
+			cnt.v_reactivated++;
 		vm_pageq_remove(m);
 		if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) {
 			if (m->act_count < ACT_INIT)
@@ -1286,7 +1286,7 @@ _vm_page_deactivate(vm_page_t m, int athead)
 		return;
 	if (m->wire_count == 0 && (m->flags & PG_UNMANAGED) == 0) {
 		if (VM_PAGE_INQUEUE1(m, PQ_CACHE))
-			PCPU_INC(cnt.v_reactivated);
+			cnt.v_reactivated++;
 		vm_page_flag_clear(m, PG_WINATCFLS);
 		vm_pageq_remove(m);
 		if (athead)
@@ -1295,11 +1295,6 @@ _vm_page_deactivate(vm_page_t m, int athead)
 			TAILQ_INSERT_TAIL(&vm_page_queues[PQ_INACTIVE].pl, m, pageq);
 		VM_PAGE_SETQUEUE2(m, PQ_INACTIVE);
 		vm_page_queues[PQ_INACTIVE].lcnt++;
-
-		/*
-		 * Just not use an atomic here since vm_page_queues_lock
-		 * alredy protects this field.
-		 */
 		cnt.v_inactive_count++;
 	}
 }