Avoid the unnecessary acquisition of the free page queues lock when a page

is actually being added to the hold queue, not the free queue.  At the same
time, avoid unnecessary tests to wake up threads waiting for free memory
and the idle thread that zeroes free pages.  (These tests will be performed
later when the page finally moves from the hold queue to the free queue.)

1 files changed, 5 insertions, 4 deletions

diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index a73d76d..08c13e1 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -1146,11 +1146,12 @@ vm_page_free_toq(vm_page_t m)
 	}
 	if (m->hold_count != 0) {
 		m->flags &= ~PG_ZERO;
-		VM_PAGE_SETQUEUE2(m, PQ_HOLD);
-	} else
-		VM_PAGE_SETQUEUE1(m, PQ_FREE);
-	pq = &vm_page_queues[VM_PAGE_GETQUEUE(m)];
+		vm_pageq_enqueue(PQ_HOLD, m);
+		return;
+	}
+	VM_PAGE_SETQUEUE1(m, PQ_FREE);
 	mtx_lock(&vm_page_queue_free_mtx);
+	pq = &vm_page_queues[VM_PAGE_GETQUEUE(m)];
 	pq->lcnt++;
 	++(*pq->cnt);