DOKK / manpages / debian 12 / liburing-dev / io_uring_buf_ring_cq_advance.3.en
io_uring_buf_ring_cq_advance(3) liburing Manual io_uring_buf_ring_cq_advance(3)

io_uring_buf_ring_cq_advance - advance index of provided buffer and CQ ring

#include <liburing.h>
void io_uring_buf_ring_cq_advance(struct io_uring *ring,
                                  struct io_uring_buf_ring *br,
                                  int count);

The io_uring_buf_ring_cq_advance(3) commits count previously added buffers to the shared buffer ring br, making them visible to the kernel and hence consumable. This passes ownership of the buffer to the ring. At the same time, it advances the CQ ring of ring by count amount. This effectively bundles both a io_uring_buf_ring_advance(3) call and a io_uring_cq_avance(3) into one operation. Since updating either ring index entails a store memory barrier, doing both at once is more efficient.

None

io_uring_register_buf_ring(3), io_uring_buf_ring_add(3), io_uring_buf_ring_advance(3)

May 18, 2022 liburing-2.2