Protect all modifications to paging_in_progress with splvm(). The i386

managed to avoid corruption of this variable by luck (the compiler used a
memory read-modify-write instruction which wasn't interruptable) but other
architectures cannot.

With this change, I am now able to 'make buildworld' on the alpha (sfx: the
crowd goes wild...)
This commit is contained in:
Doug Rabson 1998-08-06 08:33:19 +00:00
parent 757be9d291
commit d474eaaa5f
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=38135
7 changed files with 38 additions and 19 deletions

View File

@ -11,7 +11,7 @@
* 2. Absolutely no warranty of function or purpose is made by the author
* John S. Dyson.
*
* $Id: vfs_bio.c,v 1.166 1998/07/08 01:04:27 julian Exp $
* $Id: vfs_bio.c,v 1.167 1998/07/13 07:05:55 bde Exp $
*/
/*
@ -2104,7 +2104,7 @@ SYSCTL_PROC(_kern, KERN_UPDATEINTERVAL, update, CTLTYPE_INT|CTLFLAG_RW,
void
vfs_unbusy_pages(struct buf * bp)
{
int i;
int i, s;
if (bp->b_flags & B_VMIO) {
struct vnode *vp = bp->b_vp;
@ -2123,7 +2123,9 @@ vfs_unbusy_pages(struct buf * bp)
bp->b_pages[i] = m;
pmap_qenter(trunc_page(bp->b_data), bp->b_pages, bp->b_npages);
}
s = splvm();
--obj->paging_in_progress;
splx(s);
m->flags &= ~PG_ZERO;
PAGE_BWAKEUP(m);
}
@ -2221,7 +2223,7 @@ vfs_page_set_valid(struct buf *bp, vm_ooffset_t off, int pageno, vm_page_t m)
void
vfs_busy_pages(struct buf * bp, int clear_modify)
{
int i,s;
int i, s;
if (bp->b_flags & B_VMIO) {
struct vnode *vp = bp->b_vp;
@ -2248,7 +2250,9 @@ vfs_busy_pages(struct buf * bp, int clear_modify)
m->flags &= ~PG_ZERO;
if ((bp->b_flags & B_CLUSTER) == 0) {
s = splvm();
obj->paging_in_progress++;
splx(s);
m->busy++;
}

View File

@ -33,7 +33,7 @@
* SUCH DAMAGE.
*
* @(#)vfs_cluster.c 8.7 (Berkeley) 2/13/94
* $Id: vfs_cluster.c,v 1.65 1998/07/11 10:45:45 bde Exp $
* $Id: vfs_cluster.c,v 1.66 1998/07/29 17:38:14 bde Exp $
*/
#include "opt_debug_cluster.h"
@ -309,7 +309,7 @@ cluster_rbuild(vp, filesize, lbn, blkno, size, run, fbp)
{
struct buf *bp, *tbp;
daddr_t bn;
int i, inc, j;
int i, inc, j, s;
#ifdef DIAGNOSTIC
if (size != vp->v_mount->mnt_stat.f_iosize)
@ -417,8 +417,10 @@ cluster_rbuild(vp, filesize, lbn, blkno, size, run, fbp)
for (j = 0; j < tbp->b_npages; j += 1) {
vm_page_t m;
m = tbp->b_pages[j];
s = splvm();
++m->busy;
++m->object->paging_in_progress;
splx(s);
if ((bp->b_npages == 0) ||
(bp->b_pages[bp->b_npages-1] != m)) {
bp->b_pages[bp->b_npages] = m;
@ -782,8 +784,10 @@ cluster_wbuild(vp, size, start_lbn, len)
for (j = 0; j < tbp->b_npages; j += 1) {
m = tbp->b_pages[j];
s = splvm();
++m->busy;
++m->object->paging_in_progress;
splx(s);
if ((bp->b_npages == 0) ||
(bp->b_pages[bp->b_npages - 1] != m)) {
bp->b_pages[bp->b_npages] = m;

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@ -66,7 +66,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_fault.c,v 1.84 1998/07/11 12:07:52 bde Exp $
* $Id: vm_fault.c,v 1.85 1998/07/22 09:38:04 dg Exp $
*/
/*
@ -241,7 +241,7 @@ RetryFault:;
* they will stay around as well.
*/
vm_object_reference(fs.first_object);
fs.first_object->paging_in_progress++;
vm_object_pip_add(fs.first_object, 1);
fs.vp = vnode_pager_lock(fs.first_object);
if ((fault_type & VM_PROT_WRITE) &&
@ -525,7 +525,7 @@ RetryFault:;
vm_object_pip_wakeup(fs.object);
}
fs.object = next_object;
fs.object->paging_in_progress++;
vm_object_pip_add(fs.object, 1);
}
}

View File

@ -61,7 +61,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_map.c,v 1.131 1998/07/11 11:30:43 bde Exp $
* $Id: vm_map.c,v 1.132 1998/07/14 12:14:58 bde Exp $
*/
/*
@ -2001,7 +2001,7 @@ vm_map_split(entry)
}
if (orig_object->type == OBJT_SWAP) {
orig_object->paging_in_progress++;
vm_object_pip_add(orig_object, 1);
/*
* copy orig_object pages into new_object
* and destroy unneeded pages in
@ -2778,7 +2778,7 @@ vm_freeze_copyopts(object, froma, toa)
continue;
}
robject->paging_in_progress++;
vm_object_pip_add(robject, 1);
for (idx = 0; idx < robject->size; idx++) {

View File

@ -61,7 +61,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_object.c,v 1.124 1998/07/11 11:30:45 bde Exp $
* $Id: vm_object.c,v 1.125 1998/07/14 12:26:15 bde Exp $
*/
/*
@ -1102,9 +1102,9 @@ vm_object_collapse(object)
*/
if (backing_object->type == OBJT_SWAP) {
backing_object->paging_in_progress++;
vm_object_pip_add(backing_object, 1);
if (object->type == OBJT_SWAP) {
object->paging_in_progress++;
vm_object_pip_add(object, 1);
/*
* copy shadow object pages into ours
* and destroy unneeded pages in
@ -1118,7 +1118,7 @@ vm_object_collapse(object)
OFF_TO_IDX(object->backing_object_offset), TRUE);
vm_object_pip_wakeup(object);
} else {
object->paging_in_progress++;
vm_object_pip_add(object, 1);
/*
* move the shadow backing_object's pager data to
* "object" and convert "object" type to OBJT_SWAP.
@ -1314,7 +1314,7 @@ vm_object_page_remove(object, start, end, clean_only)
all = ((end == 0) && (start == 0));
object->paging_in_progress++;
vm_object_pip_add(object, 1);
again:
size = end - start;
if (all || size > 4 || size >= object->size / 4) {

View File

@ -61,7 +61,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_object.h,v 1.48 1998/04/29 04:28:12 dyson Exp $
* $Id: vm_object.h,v 1.49 1998/05/04 17:12:53 dyson Exp $
*/
/*
@ -160,10 +160,21 @@ extern vm_object_t kmem_object;
#endif /* KERNEL */
#ifdef KERNEL
static __inline void
vm_object_pip_add(vm_object_t object, int i)
{
int s = splvm();
object->paging_in_progress += i;
splx(s);
}
static __inline void
vm_object_pip_wakeup(vm_object_t object)
{
int s = splvm();
object->paging_in_progress--;
splx(s);
if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
object->flags &= ~OBJ_PIPWNT;
wakeup(object);

View File

@ -65,7 +65,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_pageout.c,v 1.122 1998/06/02 05:39:13 dyson Exp $
* $Id: vm_pageout.c,v 1.123 1998/07/10 17:58:35 alex Exp $
*/
/*
@ -367,7 +367,7 @@ vm_pageout_flush(mc, count, flags)
}
object = mc[0]->object;
object->paging_in_progress += count;
vm_object_pip_add(object, count);
vm_pager_put_pages(object, mc, count,
(flags | ((object == kernel_object) ? OBJPC_SYNC : 0)),