kernel/bpf/ringbuf.c

317 	unsigned long cons_pos, prod_pos, over_pos;
319 	cons_pos = smp_load_acquire(&rb->consumer_pos);
324 		return prod_pos - max(cons_pos, over_pos);
327 		return prod_pos - cons_pos;
433 				  unsigned long cons_pos,
451 	if (new_prod_pos - cons_pos > rb->mask)
465 	unsigned long cons_pos, prod_pos, new_prod_pos, pend_pos, over_pos, flags;
476 	cons_pos = smp_load_acquire(&rb->consumer_pos);
494 	if (!bpf_ringbuf_has_space(rb, new_prod_pos, cons_pos, pend_pos)) {
561 	unsigned long rec_pos, cons_pos;
579 	cons_pos = smp_load_acquire(&rb->consumer_pos) & rb->mask;
583 	else if (cons_pos == rec_pos && !(flags & BPF_RB_NO_WAKEUP))
752 	u64 cons_pos, prod_pos;
760 	cons_pos = smp_load_acquire(&rb->consumer_pos);
761 	if (cons_pos >= prod_pos)
764 	hdr = (u32 *)((uintptr_t)rb->data + (uintptr_t)(cons_pos & rb->mask));
772 	if (total_len > prod_pos - cons_pos)
790 		smp_store_release(&rb->consumer_pos, cons_pos + total_len);
798 			   (uintptr_t)((cons_pos + BPF_RINGBUF_HDR_SZ) & rb->mask));