Arnd Bergmann a écrit :
> We have very similar code for rx statistics in
> two places in the macvlan driver, with a third
> one being added in the next patch.
> 
> Consolidate them into one function to improve
> overall readability of the driver.
> 
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
> ---
>  drivers/net/macvlan.c |   63 +++++++++++++++++++++++++-----------------------
>  1 files changed, 33 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
> index ae2b5c7..a0dea23 100644
> --- a/drivers/net/macvlan.c
> +++ b/drivers/net/macvlan.c
> @@ -116,42 +116,53 @@ static int macvlan_addr_busy(const struct macvlan_port 
> *port,
>       return 0;
>  }
>  
> +static inline void macvlan_count_rx(const struct macvlan_dev *vlan, int 
> length,
> +                          int success, int multicast)

success and multicast should be declared as bool

> +{
> +     struct macvlan_rx_stats *rx_stats;
> +
> +     rx_stats = per_cpu_ptr(vlan->rx_stats, smp_processor_id());
> +     rx_stats->rx_packets += success != 0;
> +     rx_stats->rx_bytes   += success ? length : 0;
> +     rx_stats->multicast  += success && multicast;
> +     rx_stats->rx_errors  += !success;
> +}
> +

I find following more readable, it probably generates more branches,
but avoid dirtying rx_errors if it is in another cache line.

if (likely(success)) {
        rx_stats->rx_packets++;
        rx_stats->rx_bytes += length;
        if (multicast)
                rx_stats->multicast++;
} else {
        rx_stats->rx_errors++;
}


> -     rx_stats = per_cpu_ptr(vlan->rx_stats, smp_processor_id());
>       skb = skb_share_check(skb, GFP_ATOMIC);
> -     if (skb == NULL) {
> -             rx_stats->rx_errors++;
> -             return NULL;
> -     }
> -
> -     rx_stats->rx_bytes += skb->len + ETH_HLEN;
> -     rx_stats->rx_packets++;
> +     macvlan_count_rx(vlan, skb->len + ETH_HLEN, likely(skb != NULL), 0);

its not _likely_ that skb != NULL, its a fact :)

-> macvlan_count_rx(vlan, skb->len + ETH_HLEN, true, false);

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/virtualization

Reply via email to