all_buf 870 kernel/events/ring_buffer.c void *all_buf; all_buf 881 kernel/events/ring_buffer.c all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE); all_buf 882 kernel/events/ring_buffer.c if (!all_buf) all_buf 885 kernel/events/ring_buffer.c rb->user_page = all_buf; all_buf 886 kernel/events/ring_buffer.c rb->data_pages[0] = all_buf + PAGE_SIZE;