Currently, libbpf uses the number of combined channels as the maximum queue number. However, the kernel has a different limitation: - xdp_reg_umem_at_qid() allows up to max(RX queues, TX queues). - ethtool_set_channels() checks for UMEMs in queues up to combined_count + max(rx_count, tx_count). libbpf shouldn't limit applications to a lower max queue number. Account for non-combined RX and TX channels when calculating the max queue number. Use the same formula that is used in ethtool. Signed-off-by: Maxim Mikityanskiy <maximmi@xxxxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx> Acked-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx> --- tools/lib/bpf/xsk.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index bf15a80a37c2..86107857e1f0 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -334,13 +334,13 @@ static int xsk_get_max_queues(struct xsk_socket *xsk) goto out; } - if (channels.max_combined == 0 || errno == EOPNOTSUPP) + ret = channels.max_combined + max(channels.max_rx, channels.max_tx); + + if (ret == 0 || errno == EOPNOTSUPP) /* If the device says it has no channels, then all traffic * is sent to a single stream, so max queues = 1. */ ret = 1; - else - ret = channels.max_combined; out: close(fd); -- 2.19.1
