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Fedor Pchelkin writes: > Actually the trick with rounding up allows to calculate seq numbers > efficiently, avoiding a more consuming 'mod' operation used in the > current patch. Indeed, that was the intention. > So another approach to fix the problem would be to precompute the rounded > up value of echo_skb_max and pass it to alloc_candev() making the size of > the underlying echo_skb[] sufficient. I believe that is preferable---if memory usage is a concern KVASER_PCIEFD_CAN_TX_MAX_COUNT could be lowered by one. Something like the following: diff --git a/drivers/net/can/kvaser_pciefd.c b/drivers/net/can/kvaser_pciefd.c index f6921368cd14..0071a51ce2c1 100644 --- a/drivers/net/can/kvaser_pciefd.c +++ b/drivers/net/can/kvaser_pciefd.c @@ -966,7 +966,7 @@ static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie) u32 status, tx_nr_packets_max; netdev = alloc_candev(sizeof(struct kvaser_pciefd_can), - KVASER_PCIEFD_CAN_TX_MAX_COUNT); + roundup_pow_of_two(KVASER_PCIEFD_CAN_TX_MAX_COUNT)); if (!netdev) return -ENOMEM; @@ -995,7 +995,6 @@ static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie) can->tx_max_count = min(KVASER_PCIEFD_CAN_TX_MAX_COUNT, tx_nr_packets_max - 1); can->can.clock.freq = pcie->freq; - can->can.echo_skb_max = roundup_pow_of_two(can->tx_max_count); spin_lock_init(&can->lock); can->can.bittiming_const = &kvaser_pciefd_bittiming_const; /Axel Forsman