diff options
| author | alc <alc@FreeBSD.org> | 2003-06-22 02:35:06 +0000 |
|---|---|---|
| committer | alc <alc@FreeBSD.org> | 2003-06-22 02:35:06 +0000 |
| commit | 17a394677499453b70b54c9df6978b192d58b581 (patch) | |
| tree | acc0714aa29b70d41bd3f13c2c54375641efd09a /sys/vm | |
| parent | ee2d512823a307e30456534f1160f12239b021b3 (diff) | |
| download | FreeBSD-src-17a394677499453b70b54c9df6978b192d58b581.zip FreeBSD-src-17a394677499453b70b54c9df6978b192d58b581.tar.gz | |
Complete the vm object locking in vm_object_backing_scan(); specifically,
deal with the case where we need to sleep on a busy page with two vm object
locks held.
Diffstat (limited to 'sys/vm')
| -rw-r--r-- | sys/vm/vm_object.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c index 274d490..dd1d907 100644 --- a/sys/vm/vm_object.c +++ b/sys/vm/vm_object.c @@ -1272,7 +1272,8 @@ vm_object_backing_scan(vm_object_t object, int op) vm_pindex_t backing_offset_index; s = splvm(); - GIANT_REQUIRED; + VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); + VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); backing_object = object->backing_object; backing_offset_index = OFF_TO_IDX(object->backing_object_offset); @@ -1364,7 +1365,15 @@ vm_object_backing_scan(vm_object_t object, int op) continue; } } else if (op & OBSC_COLLAPSE_WAIT) { - if (vm_page_sleep_if_busy(p, TRUE, "vmocol")) { + if ((p->flags & PG_BUSY) || p->busy) { + vm_page_flag_set(p, + PG_WANTED | PG_REFERENCED); + VM_OBJECT_UNLOCK(backing_object); + VM_OBJECT_UNLOCK(object); + msleep(p, &vm_page_queue_mtx, + PDROP | PVM, "vmocol", 0); + VM_OBJECT_LOCK(object); + VM_OBJECT_LOCK(backing_object); /* * If we slept, anything could have * happened. Since the object is @@ -1536,7 +1545,6 @@ vm_object_collapse(vm_object_t object) * case. */ if (backing_object->ref_count == 1) { -/* XXX */ VM_OBJECT_UNLOCK(object); /* * If there is exactly one reference to the backing * object, we can collapse it into the parent. @@ -1557,7 +1565,6 @@ vm_object_collapse(vm_object_t object) * new swapper is able to optimize the * destroy-source case. */ - VM_OBJECT_LOCK(object); vm_object_pip_add(object, 1); VM_OBJECT_UNLOCK(object); swap_pager_copy( @@ -1566,7 +1573,6 @@ vm_object_collapse(vm_object_t object) OFF_TO_IDX(object->backing_object_offset), TRUE); VM_OBJECT_LOCK(object); vm_object_pip_wakeup(object); - VM_OBJECT_UNLOCK(object); VM_OBJECT_LOCK(backing_object); vm_object_pip_wakeup(backing_object); @@ -1602,6 +1608,7 @@ vm_object_collapse(vm_object_t object) object->backing_object_offset += backing_object->backing_object_offset; +/* XXX */ VM_OBJECT_UNLOCK(object); /* * Discard backing_object. |
