rb_data_page_commit
tail = rb_data_page_commit(dpage);
val, meta->buffers[val], dpage ? rb_data_page_commit(dpage) : -1);
if (!rb_data_page_commit(dpage))
return rb_data_page_commit(dpage) & ~RB_MISSED_MASK;
return rb_data_page_commit(bpage->page);
tail = rb_data_page_commit(dpage);
if (tail <= 8 || tail > rb_data_page_commit(dpage))
if (!missed_events && rb_data_page_commit(dpage) & RB_MISSED_EVENTS)