Module Name: src
Committed By: uebayasi
Date: Sun Jan 31 09:20:31 UTC 2010
Modified Files:
src/sys/uvm: uvm_fault.c
Log Message:
uvm_fault_internal:
Move local variables around to isolate contexts. Note that remaining variables
are global in that function, and some hold state across re-fault.
Slilently clean-up the "eoff" mess.
(Superfluous braces will go once things settle down.)
To generate a diff of this commit:
cvs rdiff -u -r1.136 -r1.137 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:1.136 src/sys/uvm/uvm_fault.c:1.137
--- src/sys/uvm/uvm_fault.c:1.136 Sun Jan 31 07:47:29 2010
+++ src/sys/uvm/uvm_fault.c Sun Jan 31 09:20:31 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: uvm_fault.c,v 1.136 2010/01/31 07:47:29 uebayasi Exp $ */
+/* $NetBSD: uvm_fault.c,v 1.137 2010/01/31 09:20:31 uebayasi Exp $ */
/*
*
@@ -39,7 +39,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.136 2010/01/31 07:47:29 uebayasi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_fault.c,v 1.137 2010/01/31 09:20:31 uebayasi Exp $");
#include "opt_uvmhist.h"
@@ -697,23 +697,21 @@
vm_prot_t access_type, int fault_flag)
{
struct uvm_faultinfo ufi;
- vm_prot_t enter_prot, check_prot;
- bool wired, narrow, promote, locked, shadowed, wire_fault, cow_now;
- int npages, nback, nforw, centeridx, error, lcv, gotpages;
- vaddr_t startva, currva;
- voff_t uoff;
+ vm_prot_t enter_prot;
+ bool wired, narrow, shadowed, wire_fault, cow_now;
+ int npages, centeridx, error;
+ vaddr_t startva;
struct vm_amap *amap;
struct uvm_object *uobj;
- struct vm_anon *anons_store[UVM_MAXRANGE], **anons, *anon, *oanon;
+ struct vm_anon *anons_store[UVM_MAXRANGE], **anons;
struct vm_anon *anon_spare;
- struct vm_page *pages[UVM_MAXRANGE], *pg, *uobjpage;
+ struct vm_page *pages[UVM_MAXRANGE], *uobjpage;
UVMHIST_FUNC("uvm_fault"); UVMHIST_CALLED(maphist);
UVMHIST_LOG(maphist, "(map=0x%x, vaddr=0x%x, at=%d, ff=%d)",
orig_map, vaddr, access_type, fault_flag);
- anon = anon_spare = NULL;
- pg = NULL;
+ anon_spare = NULL;
uvmexp.faults++; /* XXX: locking? */
@@ -736,6 +734,11 @@
*/
ReFault:
+/* uvm_fault_prepare */
+ {
+ vm_prot_t check_prot;
+ int nback, nforw;
+
/*
* lookup and lock the maps
*/
@@ -873,7 +876,7 @@
}
/* offset from entry's start to pgs' start */
- voff_t eoff = startva - ufi.entry->start;
+ const voff_t eoff = startva - ufi.entry->start;
/* locked: maps(read) */
UVMHIST_LOG(maphist, " narrow=%d, back=%d, forw=%d, startva=0x%x",
@@ -911,6 +914,8 @@
/* flush object? */
if (uobj) {
+ voff_t uoff;
+
uoff = ufi.entry->offset + eoff;
mutex_enter(&uobj->vmobjlock);
(void) (uobj->pgops->pgo_put)(uobj, uoff, uoff +
@@ -922,9 +927,19 @@
anons += nback;
startva += (nback << PAGE_SHIFT);
npages -= nback;
- nback = centeridx = 0;
- eoff = startva - ufi.entry->start;
+ centeridx = 0;
}
+ }
+
+ /*
+ * => startva is fixed
+ * => npages is fixed
+ */
+
+/* uvm_fault_upper_lookup */
+ {
+ int lcv;
+ vaddr_t currva;
/* locked: maps(read), amap(if there) */
KASSERT(amap == NULL || mutex_owned(&amap->am_l));
@@ -938,6 +953,7 @@
currva = startva;
shadowed = false;
for (lcv = 0 ; lcv < npages ; lcv++, currva += PAGE_SIZE) {
+ struct vm_anon *anon;
/*
* dont play with VAs that are already mapped
@@ -1009,10 +1025,12 @@
* XXX Actually, that is bad; pmap_enter() should just fail in that
* XXX case. --thorpej
*/
+ }
if (shadowed == true)
goto Case1;
+/* uvm_fault_lower */
/*
* if the desired page is not shadowed by the amap and we have a
* backing object, then we check to see if the backing object would
@@ -1022,6 +1040,7 @@
*/
if (uobj && uobj->pgops->pgo_fault != NULL) {
+/* uvm_fault_lower_special */
mutex_enter(&uobj->vmobjlock);
/* locked: maps(read), amap (if there), uobj */
error = uobj->pgops->pgo_fault(&ufi, startva, pages, npages,
@@ -1037,6 +1056,11 @@
goto done;
}
+/* uvm_fault_lower_generic_lookup */
+ {
+ int lcv, gotpages;
+ vaddr_t currva;
+
/*
* now, if the desired page is not shadowed by the amap and we have
* a backing object that does not have a special fault routine, then
@@ -1059,7 +1083,7 @@
uvmexp.fltlget++;
gotpages = npages;
- (void) uobj->pgops->pgo_get(uobj, ufi.entry->offset + eoff,
+ (void) uobj->pgops->pgo_get(uobj, ufi.entry->offset + startva - ufi.entry->start,
pages, &gotpages, centeridx,
access_type & MASK(ufi.entry),
ufi.entry->advice, PGO_LOCKED);
@@ -1153,6 +1177,7 @@
lower_fault_lookup_done:
{}
+ }
/* locked: maps(read), amap(if there), uobj(if !null), uobjpage(if !null) */
KASSERT(!shadowed);
@@ -1181,7 +1206,11 @@
goto Case2;
+/* uvm_fault_upper */
Case1:
+ {
+ struct vm_anon *anon, *oanon;
+
/* locked: maps(read), amap */
KASSERT(mutex_owned(&amap->am_l));
@@ -1269,6 +1298,7 @@
/* >1 case is already ok */
if (anon->an_ref == 1) {
+ struct vm_page *pg;
/* get new un-owned replacement page */
pg = uvm_pagealloc(NULL, 0, NULL, 0);
@@ -1339,6 +1369,7 @@
* if we are out of anon VM we kill the process (XXX: could wait?).
*/
+ struct vm_page *pg;
if (cow_now && anon->an_ref > 1) {
UVMHIST_LOG(maphist, " case 1B: COW fault",0,0,0,0);
@@ -1452,8 +1483,14 @@
pmap_update(ufi.orig_map->pmap);
error = 0;
goto done;
+ }
+/* uvm_fault_lower_generic */
Case2:
+ {
+ struct vm_anon *anon;
+ bool promote;
+
/*
* handle case 2: faulting on backing object or zero fill
*/
@@ -1496,6 +1533,10 @@
/* update rusage counters */
curlwp->l_ru.ru_minflt++;
} else {
+ bool locked;
+ int gotpages;
+ voff_t uoff;
+
/* update rusage counters */
curlwp->l_ru.ru_majflt++;
@@ -1613,6 +1654,7 @@
KASSERT(uobj == NULL || uobj == uobjpage->uobject);
KASSERT(uobj == NULL || !UVM_OBJ_IS_CLEAN(uobjpage->uobject) ||
(uobjpage->flags & PG_CLEAN) != 0);
+ struct vm_page *pg;
if (promote == false) {
/*
@@ -1840,6 +1882,8 @@
pmap_update(ufi.orig_map->pmap);
UVMHIST_LOG(maphist, "<- done (SUCCESS!)",0,0,0,0);
error = 0;
+ }
+
done:
if (anon_spare != NULL) {
anon_spare->an_ref--;
