Push down the acquisition and release of the page queues lock into

pmap_protect() and pmap_remove().  In general, they require the lock in
order to modify a page's pv list or flags.  In some cases, however,
pmap_protect() can avoid acquiring the lock.

1 files changed, 7 insertions, 2 deletions

diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index 9dd4f67..39436b9 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -1602,6 +1602,8 @@ pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
 	 */
 	if (pmap->pm_stats.resident_count == 0)
 		return;
+
+	vm_page_lock_queues();
 	PMAP_LOCK(pmap);
 
 	/*
@@ -1613,8 +1615,7 @@ pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
 		pde = pmap_pde(pmap, sva);
 		if (pde && (*pde & PG_PS) == 0) {
 			pmap_remove_page(pmap, sva);
-			PMAP_UNLOCK(pmap);
-			return;
+			goto out;
 		}
 	}
 
@@ -1684,6 +1685,8 @@ pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
 
 	if (anyvalid)
 		pmap_invalidate_all(pmap);
+out:
+	vm_page_unlock_queues();
 	PMAP_UNLOCK(pmap);
 }
 
@@ -1778,6 +1781,7 @@ pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
 
 	anychanged = 0;
 
+	vm_page_lock_queues();
 	PMAP_LOCK(pmap);
 	for (; sva < eva; sva = va_next) {
 
@@ -1856,6 +1860,7 @@ pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
 	}
 	if (anychanged)
 		pmap_invalidate_all(pmap);
+	vm_page_unlock_queues();
 	PMAP_UNLOCK(pmap);
 }