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Index: sys/vm/vm_page.c
===================================================================
--- sys/vm/vm_page.c
+++ sys/vm/vm_page.c
@@ -4825,8 +4825,35 @@
/*
* Grab a page, waiting until we are waken up due to the page
* changing state. We keep on waiting, if the page continues
- * to be in the object. If the page doesn't exist, first allocate it
- * and then conditionally zero it.
+ * to be in the object.
+ *
+ * This routine may sleep.
+ *
+ * The object must be locked on entry. The lock will, however, be released
+ * and reacquired if the routine sleeps.
+ */
+static inline vm_page_t
+vm_page_grab_lookup(struct pctrie_iter *pages, vm_object_t object,
+ vm_pindex_t pindex, int allocflags, bool *found)
+{
+ vm_page_t m;
+
+ *found = false;
+ while ((m = vm_radix_iter_lookup(pages, pindex)) != NULL &&
+ !vm_page_tryacquire(m, allocflags)) {
+ if (!vm_page_grab_sleep(object, m, pindex, "pgrbwt",
+ allocflags, true)) {
+ *found = true;
+ return (NULL);
+ }
+ pctrie_iter_reset(pages);
+ }
+ return (m);
+}
+
+/*
+ * Grab a page. Keep on waiting, as long as the page exists in the object. If
+ * the page doesn't exist, first allocate it and then conditionally zero it.
*
* This routine may sleep.
*
@@ -4836,33 +4863,34 @@
vm_page_t
vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
{
- vm_page_t m;
+ struct pctrie_iter pages;
+ vm_page_t m, mpred;
+ bool found;
VM_OBJECT_ASSERT_WLOCKED(object);
vm_page_grab_check(allocflags);
-retrylookup:
- if ((m = vm_page_lookup(object, pindex)) != NULL) {
- if (!vm_page_tryacquire(m, allocflags)) {
- if (vm_page_grab_sleep(object, m, pindex, "pgrbwt",
- allocflags, true))
- goto retrylookup;
+ vm_page_iter_init(&pages, object);
+ while ((m = vm_page_grab_lookup(
+ &pages, object, pindex, allocflags, &found)) == NULL) {
+ if ((allocflags & VM_ALLOC_NOCREAT) != 0)
return (NULL);
+ if (found &&
+ (allocflags & (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL)) != 0)
+ return (NULL);
+ mpred = vm_radix_iter_lookup_le(&pages, pindex);
+ m = vm_page_alloc_after(object, pindex,
+ vm_page_grab_pflags(allocflags), mpred);
+ if (m != NULL) {
+ if ((allocflags & VM_ALLOC_ZERO) != 0 &&
+ (m->flags & PG_ZERO) == 0)
+ pmap_zero_page(m);
+ break;
}
- goto out;
- }
- if ((allocflags & VM_ALLOC_NOCREAT) != 0)
- return (NULL);
- m = vm_page_alloc(object, pindex, vm_page_grab_pflags(allocflags));
- if (m == NULL) {
- if ((allocflags & (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL)) != 0)
+ if ((allocflags &
+ (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL)) != 0)
return (NULL);
- goto retrylookup;
}
- if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0)
- pmap_zero_page(m);
-
-out:
vm_page_grab_release(m, allocflags);
return (m);
@@ -5054,48 +5082,57 @@
}
/*
- * Fill a partial page with zeroes. The object write lock is held on entry and
- * exit, but may be temporarily released.
+ * Grab a page. Keep on waiting, as long as the page exists in the object. If
+ * the page doesn't exist, and the pager has it, allocate it and zero part of
+ * it.
+ *
+ * The object must be locked on entry. This routine may sleep. The lock will,
+ * however, be released and reacquired if the routine sleeps.
*/
int
vm_page_grab_zero_partial(vm_object_t object, vm_pindex_t pindex, int base,
int end)
{
- vm_page_t m;
- int rv;
+ struct pctrie_iter pages;
+ vm_page_t m, mpred;
+ int allocflags, rv;
+ bool found;
VM_OBJECT_ASSERT_WLOCKED(object);
KASSERT(base >= 0, ("%s: base %d", __func__, base));
KASSERT(end - base <= PAGE_SIZE, ("%s: base %d end %d", __func__, base,
end));
-retry:
- m = vm_page_grab(object, pindex, VM_ALLOC_NOCREAT);
- if (m != NULL) {
- MPASS(vm_page_all_valid(m));
- } else if (vm_pager_has_page(object, pindex, NULL, NULL)) {
- m = vm_page_alloc(object, pindex,
- VM_ALLOC_NORMAL | VM_ALLOC_WAITFAIL);
- if (m == NULL)
- goto retry;
- vm_object_pip_add(object, 1);
- VM_OBJECT_WUNLOCK(object);
- rv = vm_pager_get_pages(object, &m, 1, NULL, NULL);
- VM_OBJECT_WLOCK(object);
- vm_object_pip_wakeup(object);
- if (rv != VM_PAGER_OK) {
- vm_page_free(m);
- return (EIO);
- }
+ allocflags = VM_ALLOC_NOCREAT | VM_ALLOC_NORMAL | VM_ALLOC_WAITFAIL;
+ vm_page_iter_init(&pages, object);
+ while ((m = vm_page_grab_lookup(
+ &pages, object, pindex, allocflags, &found)) == NULL) {
+ if (!vm_pager_has_page(object, pindex, NULL, NULL))
+ return (0);
+ mpred = vm_radix_iter_lookup_le(&pages, pindex);
+ m = vm_page_alloc_after(object, pindex,
+ vm_page_grab_pflags(allocflags), mpred);
+ if (m != NULL) {
+ vm_object_pip_add(object, 1);
+ VM_OBJECT_WUNLOCK(object);
+ rv = vm_pager_get_pages(object, &m, 1, NULL, NULL);
+ VM_OBJECT_WLOCK(object);
+ vm_object_pip_wakeup(object);
+ if (rv != VM_PAGER_OK) {
+ vm_page_free(m);
+ return (EIO);
+ }
- /*
- * Since the page was not resident, and therefore not recently
- * accessed, immediately enqueue it for asynchronous laundering.
- * The current operation is not regarded as an access.
- */
- vm_page_launder(m);
- } else
- return (0);
+ /*
+ * Since the page was not resident, and therefore not
+ * recently accessed, immediately enqueue it for
+ * asynchronous laundering. The current operation is
+ * not regarded as an access.
+ */
+ vm_page_launder(m);
+ break;
+ }
+ }
pmap_zero_page_area(m, base, end - base);
KASSERT(vm_page_all_valid(m), ("%s: page %p is invalid", __func__, m));

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