page_cache_sync_ra
void page_cache_sync_ra(struct readahead_control *, unsigned long req_count);
page_cache_sync_ra(&ractl, req_count);
DEFINE_EVENT(page_cache_ra_op, page_cache_sync_ra,
page_cache_sync_ra(&ractl, last_index - index);
page_cache_sync_ra(&ractl, ra->ra_pages);
EXPORT_SYMBOL_GPL(page_cache_sync_ra);