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charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Thu, Nov 19, 2020 at 9:33 AM Bj=C3=B6rn T=C3=B6pel wrote: > > From: Bj=C3=B6rn T=C3=B6pel > > Start using recvfrom() the l2fwd scenario, instead of poll() which is > more expensive and need additional knobs for busy-polling. > > Signed-off-by: Bj=C3=B6rn T=C3=B6pel > --- > samples/bpf/xdpsock_user.c | 25 +++++++++++-------------- > 1 file changed, 11 insertions(+), 14 deletions(-) Acked-by: Magnus Karlsson > diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c > index f90111b95b2e..24aa7511c4c8 100644 > --- a/samples/bpf/xdpsock_user.c > +++ b/samples/bpf/xdpsock_user.c > @@ -1098,8 +1098,7 @@ static void kick_tx(struct xsk_socket_info *xsk) > exit_with_error(errno); > } > > -static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk, > - struct pollfd *fds) > +static inline void complete_tx_l2fwd(struct xsk_socket_info *xsk) > { > struct xsk_umem_info *umem =3D xsk->umem; > u32 idx_cq =3D 0, idx_fq =3D 0; > @@ -1134,7 +1133,7 @@ static inline void complete_tx_l2fwd(struct xsk_soc= ket_info *xsk, > exit_with_error(-ret); > if (xsk_ring_prod__needs_wakeup(&umem->fq)) { > xsk->app_stats.fill_fail_polls++; > - ret =3D poll(fds, num_socks, opt_timeout)= ; > + recvfrom(xsk_socket__fd(xsk->xsk), NULL, = 0, MSG_DONTWAIT, NULL, NULL); > } > ret =3D xsk_ring_prod__reserve(&umem->fq, rcvd, &= idx_fq); > } > @@ -1331,19 +1330,19 @@ static void tx_only_all(void) > complete_tx_only_all(); > } > > -static void l2fwd(struct xsk_socket_info *xsk, struct pollfd *fds) > +static void l2fwd(struct xsk_socket_info *xsk) > { > unsigned int rcvd, i; > u32 idx_rx =3D 0, idx_tx =3D 0; > int ret; > > - complete_tx_l2fwd(xsk, fds); > + complete_tx_l2fwd(xsk); > > rcvd =3D xsk_ring_cons__peek(&xsk->rx, opt_batch_size, &idx_rx); > if (!rcvd) { > if (xsk_ring_prod__needs_wakeup(&xsk->umem->fq)) { > xsk->app_stats.rx_empty_polls++; > - ret =3D poll(fds, num_socks, opt_timeout); > + recvfrom(xsk_socket__fd(xsk->xsk), NULL, 0, MSG_D= ONTWAIT, NULL, NULL); > } > return; > } > @@ -1353,7 +1352,7 @@ static void l2fwd(struct xsk_socket_info *xsk, stru= ct pollfd *fds) > while (ret !=3D rcvd) { > if (ret < 0) > exit_with_error(-ret); > - complete_tx_l2fwd(xsk, fds); > + complete_tx_l2fwd(xsk); > if (xsk_ring_prod__needs_wakeup(&xsk->tx)) { > xsk->app_stats.tx_wakeup_sendtos++; > kick_tx(xsk); > @@ -1388,22 +1387,20 @@ static void l2fwd_all(void) > struct pollfd fds[MAX_SOCKS] =3D {}; > int i, ret; > > - for (i =3D 0; i < num_socks; i++) { > - fds[i].fd =3D xsk_socket__fd(xsks[i]->xsk); > - fds[i].events =3D POLLOUT | POLLIN; > - } > - > for (;;) { > if (opt_poll) { > - for (i =3D 0; i < num_socks; i++) > + for (i =3D 0; i < num_socks; i++) { > + fds[i].fd =3D xsk_socket__fd(xsks[i]->xsk= ); > + fds[i].events =3D POLLOUT | POLLIN; > xsks[i]->app_stats.opt_polls++; > + } > ret =3D poll(fds, num_socks, opt_timeout); > if (ret <=3D 0) > continue; > } > > for (i =3D 0; i < num_socks; i++) > - l2fwd(xsks[i], fds); > + l2fwd(xsks[i]); > > if (benchmark_done) > break; > -- > 2.27.0 >