/*
 * The compaction process looks at the page's modification information;
 * if compaction is running, lock the page down.
 *
 * Otherwise, flip on the scanning flag: obsolete updates cannot be
 * freed while reconciliation is in progress.
 */
locked = 0;
if (conn->compact_in_memory_pass) {
        locked = 1;
        WT_PAGE_LOCK(session, page);
} else
        for (;;) {
                F_CAS_ATOMIC(page, WT_PAGE_SCANNING, ret);
                if (ret == 0)
                        break;
                __wt_yield();
        }