Module Name: src
Committed By: thorpej
Date: Mon May 31 17:22:45 UTC 2021
Modified Files:
src/sys/arch/alpha/include: pmap.h
Log Message:
Additional comment about the range (0-1025) that's needed for the PT page
reference count, and thus now many bits we need to scare up.
To generate a diff of this commit:
cvs rdiff -u -r1.97 -r1.98 src/sys/arch/alpha/include/pmap.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/alpha/include/pmap.h
diff -u src/sys/arch/alpha/include/pmap.h:1.97 src/sys/arch/alpha/include/pmap.h:1.98
--- src/sys/arch/alpha/include/pmap.h:1.97 Mon May 31 17:16:05 2021
+++ src/sys/arch/alpha/include/pmap.h Mon May 31 17:22:44 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.h,v 1.97 2021/05/31 17:16:05 thorpej Exp $ */
+/* $NetBSD: pmap.h,v 1.98 2021/05/31 17:22:44 thorpej Exp $ */
/*-
* Copyright (c) 1998, 1999, 2000, 2001, 2007 The NetBSD Foundation, Inc.
@@ -360,6 +360,10 @@ struct vm_page_md {
* XXX These fields are only needed for pages that are used
* as PT pages. It would be nice to find safely-unused fields
* in the vm_page structure that could be used instead.
+ *
+ * (Only 11 bits are needed ... we need to be able to count from
+ * 0-1025 ... 1025 because sometimes we need to take an extra
+ * reference temporarily in pmap_enter().)
*/
unsigned int pvh_physpgrefs; /* # refs as a PT page */
unsigned int pvh_spare0; /* XXX spare field */
