Hi, I have question regarding ethtool_ops.set_coalesce parameters. >From one side, documentation (include/uapi/linux/ethtool.h) states: * Each pair of (usecs, max_frames) fields specifies that interrupts * should be coalesced until * (usecs > 0 && time_since_first_completion >= usecs) || * (max_frames > 0 && completed_frames >= max_frames) * * It is illegal to set both usecs and max_frames to zero as this * would cause interrupts to never be generated. To disable * coalescing, set usecs = 0 and max_frames = 1. So, it suggests: Drivers for hardware that does not support counting completions should validate that max_frames == !rx_usecs. Thus, I can conclude I should verify this for every pair. Then, same documentation states following must not be 0: - stats_block_coalesce_usecs - rate_sample_interval But, I see drivers either ignore unsupported values, or check that all of it are 0, see for example in drivers/net/ethernet/amd/xgbe/xgbe-ethtool.c: /* Check for not supported parameters */ if ((ec->rx_coalesce_usecs_irq) || (ec->rx_max_coalesced_frames_irq) || (ec->tx_coalesce_usecs_irq) || (ec->tx_max_coalesced_frames_irq) || (ec->stats_block_coalesce_usecs) || (ec->use_adaptive_rx_coalesce) || (ec->use_adaptive_tx_coalesce) || (ec->pkt_rate_low) || (ec->rx_coalesce_usecs_low) || (ec->rx_max_coalesced_frames_low) || (ec->tx_coalesce_usecs_low) || (ec->tx_max_coalesced_frames_low) || (ec->pkt_rate_high) || (ec->rx_coalesce_usecs_high) || (ec->rx_max_coalesced_frames_high) || (ec->tx_coalesce_usecs_high) || (ec->tx_max_coalesced_frames_high) || (ec->rate_sample_interval)) return -EOPNOTSUPP; Bottom line, my question is: what is the right way to handle parameters in ethtool_ops.set_coalesce? Thanks, Vladimir -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
