d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Optimize vm_object_split(). Specifically, make the number of iterations

Browse Source 
equal to the number of physical pages that are renamed to the new object
rather than the new object's virtual size.
This commit is contained in:
alc 2006-12-17 20:14:43 +00:00
parent 5e73797115
commit 143ffef93b
1 changed files with 14 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
sys/vm/vm_object.c
View File

@ -1287,10 +1287,10 @@ vm_object_shadow(
void
vm_object_split(vm_map_entry_t entry)
{
vm_page_t m;
vm_page_t m, m_next;
vm_object_t orig_object, new_object, source;
vm_pindex_t offidxstart;
vm_size_t idx, size;
vm_pindex_t idx, offidxstart;
vm_size_t size;
orig_object = entry->object.vm_object;
if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP)
@ -1325,12 +1325,18 @@ vm_object_split(vm_map_entry_t entry)
new_object->backing_object = source;
}
new_object->flags |= orig_object->flags & OBJ_NEEDGIANT;
retry:
if ((m = TAILQ_FIRST(&orig_object->memq)) != NULL) {
if (m->pindex < offidxstart) {
m = vm_page_splay(offidxstart, orig_object->root);
if ((orig_object->root = m)->pindex < offidxstart)
m = TAILQ_NEXT(m, listq);
}
}
vm_page_lock_queues();
for (idx = 0; idx < size; idx++) {
retry:
m = vm_page_lookup(orig_object, offidxstart + idx);
if (m == NULL)
continue;
for (; m != NULL && (idx = m->pindex - offidxstart) < size;
m = m_next) {
m_next = TAILQ_NEXT(m, listq);
/*
* We must wait for pending I/O to complete before we can
@ -1347,7 +1353,6 @@ vm_object_split(vm_map_entry_t entry)
msleep(m, VM_OBJECT_MTX(orig_object), PDROP | PVM, "spltwt", 0);
VM_OBJECT_LOCK(new_object);
VM_OBJECT_LOCK(orig_object);
vm_page_lock_queues();
goto retry;
}
vm_page_rename(m, new_object, idx);