Hillf Danton <hdanton@xxxxxxxx> wrote: > > + for (i = 0; i < wf->nr_filters; i++) { > > + wt = &wf->filters[i]; > > + if (n->type == wt->type && > > + (wt->subtype_filter[n->subtype >> 5] & > > + (1U << (n->subtype & 31))) && > > Replace the pure numbers with something easier to understand. How about the following: static bool filter_watch_notification(const struct watch_filter *wf, const struct watch_notification *n) { const struct watch_type_filter *wt; unsigned int st_bits = sizeof(wt->subtype_filter[0]) * 8; unsigned int st_index = n->subtype / st_bits; unsigned int st_bit = 1U << (n->subtype % st_bits); int i; if (!test_bit(n->type, wf->type_filter)) return false; for (i = 0; i < wf->nr_filters; i++) { wt = &wf->filters[i]; if (n->type == wt->type && (wt->subtype_filter[st_index] & st_bit) && (n->info & wt->info_mask) == wt->info_filter) return true; } return false; /* If there is a filter, the default is to reject. */ } David