Module Name: src
Committed By: uebayasi
Date: Sun Feb 28 06:52:13 UTC 2010
Modified Files:
src/sys/uvm [uebayasi-xip]: uvm_fault.c
Log Message:
Put comments why device pages skip some code paths. Don't skip accounting
for "neighbor" device pages.
To generate a diff of this commit:
cvs rdiff -u -r1.166.2.4 -r1.166.2.5 src/sys/uvm/uvm_fault.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/uvm/uvm_fault.c
diff -u src/sys/uvm/uvm_fault.c:1.166.2.4 src/sys/uvm/uvm_fault.c:1.166.2.5
--- src/sys/uvm/uvm_fault.c:1.166.2.4 Wed Feb 24 16:22:58 2010
+++ src/sys/uvm/uvm_fault.c Sun Feb 28 06:52:12 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: uvm_fault.c,v 1.166.2.4 2010/02/24 16:22:58 uebayasi Exp $ */
+/* $NetBSD: uvm_fault.c,v 1.166.2.5 2010/02/28 06:52:12 uebayasi Exp $ */
/*
*
@@ -39,7 +39,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.166.2.4 2010/02/24 16:22:58 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.166.2.5 2010/02/28 06:52:12 uebayasi Exp $");
#include "opt_uvmhist.h"
#include "opt_device_page.h"
@@ -1769,10 +1769,6 @@
mutex_enter(&uvm_pageqlock);
uvm_pageenqueue(pg);
mutex_exit(&uvm_pageqlock);
- UVMHIST_LOG(maphist,
- " MAPPING: n obj: pm=0x%x, va=0x%x, pg=0x%x",
- ufi->orig_map->pmap, currva, pg, 0);
- uvmexp.fltnomap++;
/*
* Since this page isn't the page that's actually faulting,
@@ -1790,6 +1786,11 @@
UVM_PAGE_OWN(pg, NULL);
uvm_fault_lower_neighbor_enter:
+ UVMHIST_LOG(maphist,
+ " MAPPING: n obj: pm=0x%x, va=0x%x, pg=0x%x",
+ ufi->orig_map->pmap, currva, pg, 0);
+ uvmexp.fltnomap++;
+
(void) pmap_enter(ufi->orig_map->pmap, currva,
VM_PAGE_TO_PHYS(pg),
readonly ? (flt->enter_prot & ~VM_PROT_WRITE) :
@@ -1962,8 +1963,10 @@
pg = uobjpage; /* map in the actual object */
uvmexp.flt_obj++;
- if (uvm_pageisdevice_p(uobjpage))
+ if (uvm_pageisdevice_p(uobjpage)) {
+ /* XIP'ed device pages are always read-only */
goto uvm_fault_lower_direct_done;
+ }
if (UVM_ET_ISCOPYONWRITE(ufi->entry) ||
UVM_OBJ_NEEDS_WRITEFAULT(uobjpage->uobject))
@@ -2094,8 +2097,13 @@
*/
}
- if (uvm_pageisdevice_p(uobjpage))
+ if (uvm_pageisdevice_p(uobjpage)) {
+ /*
+ * XIP devices pages are never paged out, no need to
+ * dispose.
+ */
goto uvm_fault_lower_promote_done;
+ }
/*
* dispose of uobjpage. it can't be PG_RELEASED
@@ -2176,8 +2184,10 @@
(flt->enter_prot & ~VM_PROT_WRITE) : flt->enter_prot,
flt->access_type | PMAP_CANFAIL | (flt->wire_mapping ? PMAP_WIRED : 0)) != 0) {
- if (uvm_pageisdevice_p(pg))
+ if (uvm_pageisdevice_p(pg)) {
+ /* Device pages never involve paging activity. */
goto uvm_fault_lower_enter_error_done;
+ }
/*
* No need to undo what we did; we can simply think of
