Beispiel #1
0
/*
 * Speed up the reclamation of up to "distance" pages that precede the
 * faulting pindex within the first object of the shadow chain.
 */
static void
vm_fault_cache_behind(const struct faultstate *fs, int distance)
{
	vm_object_t first_object, object;
	vm_page_t m, m_prev;
	vm_pindex_t pindex;

	object = fs->object;
	VM_OBJECT_ASSERT_WLOCKED(object);
	first_object = fs->first_object;
	if (first_object != object) {
		if (!VM_OBJECT_TRYWLOCK(first_object)) {
			VM_OBJECT_WUNLOCK(object);
			VM_OBJECT_WLOCK(first_object);
			VM_OBJECT_WLOCK(object);
		}
	}
	/* Neither fictitious nor unmanaged pages can be cached. */
	if ((first_object->flags & (OBJ_FICTITIOUS | OBJ_UNMANAGED)) == 0) {
		if (fs->first_pindex < distance)
			pindex = 0;
		else
			pindex = fs->first_pindex - distance;
		if (pindex < OFF_TO_IDX(fs->entry->offset))
			pindex = OFF_TO_IDX(fs->entry->offset);
		m = first_object != object ? fs->first_m : fs->m;
		KASSERT((m->oflags & VPO_BUSY) != 0,
		    ("vm_fault_cache_behind: page %p is not busy", m));
		m_prev = vm_page_prev(m);
		while ((m = m_prev) != NULL && m->pindex >= pindex &&
		    m->valid == VM_PAGE_BITS_ALL) {
			m_prev = vm_page_prev(m);
			if (m->busy != 0 || (m->oflags & VPO_BUSY) != 0)
				continue;
			vm_page_lock(m);
			if (m->hold_count == 0 && m->wire_count == 0) {
				pmap_remove_all(m);
				vm_page_aflag_clear(m, PGA_REFERENCED);
				if (m->dirty != 0)
					vm_page_deactivate(m);
				else
					vm_page_cache(m);
			}
			vm_page_unlock(m);
		}
	}
	if (first_object != object)
		VM_OBJECT_WUNLOCK(first_object);
}
Beispiel #2
0
/*
 * Speed up the reclamation of up to "distance" pages that precede the
 * faulting pindex within the first object of the shadow chain.
 */
static void
vm_fault_cache_behind(const struct faultstate *fs, int distance)
{
	vm_object_t first_object, object;
	vm_page_t m, m_prev;
	vm_pindex_t pindex;

	object = fs->object;
	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
	first_object = fs->first_object;
	if (first_object != object) {
		if (!VM_OBJECT_TRYLOCK(first_object)) {
			VM_OBJECT_UNLOCK(object);
			VM_OBJECT_LOCK(first_object);
			VM_OBJECT_LOCK(object);
		}
	}
	if (first_object->type != OBJT_DEVICE &&
	    first_object->type != OBJT_PHYS && first_object->type != OBJT_SG) {
		if (fs->first_pindex < distance)
			pindex = 0;
		else
			pindex = fs->first_pindex - distance;
		if (pindex < OFF_TO_IDX(fs->entry->offset))
			pindex = OFF_TO_IDX(fs->entry->offset);
		m = first_object != object ? fs->first_m : fs->m;
		KASSERT((m->oflags & VPO_BUSY) != 0,
		    ("vm_fault_cache_behind: page %p is not busy", m));
		m_prev = vm_page_prev(m);
		while ((m = m_prev) != NULL && m->pindex >= pindex &&
		    m->valid == VM_PAGE_BITS_ALL) {
			m_prev = vm_page_prev(m);
			if (m->busy != 0 || (m->oflags & VPO_BUSY) != 0)
				continue;
			vm_page_lock(m);
			if (m->hold_count == 0 && m->wire_count == 0) {
				pmap_remove_all(m);
				vm_page_aflag_clear(m, PGA_REFERENCED);
				if (m->dirty != 0)
					vm_page_deactivate(m);
				else
					vm_page_cache(m);
			}
			vm_page_unlock(m);
		}
	}
	if (first_object != object)
		VM_OBJECT_UNLOCK(first_object);
}