[ovs-dev] [PATCH 2/3] tunnel: move rt_genid to compatibility code.

[Jesse Gross]

On Dec 21, 2011, at 8:28 PM, Pravin B Shelar wrote:
> diff --git a/datapath/linux/compat/include/net/dst.h b/datapath/linux/compat/include/net/dst.h
> index f481a9d..5341daa 100644
> --- a/datapath/linux/compat/include/net/dst.h
> +++ b/datapath/linux/compat/include/net/dst.h
> @@ -14,4 +14,26 @@ static inline void skb_dst_drop(struct sk_buff *skb)
> 
> #endif
> 
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
> +/*
> + * On these kernels we have a fast mechanism to tell if the ARP cache for a
> + * particular destination has changed.
> + **/
> +#define HAVE_HH_SEQ
> +#endif
> +
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,27)
> +/*
> + * On these kernels we have a fast mechanism to tell if the routing table
> + * has changed.
> + **/
> +#define HAVE_RT_GENID

The symbols that we define shouldn't go in compatibility code.  We've had problems in the past where systems that integrated OVS need our symbols so they integrate those too but then we can't compile newer versions of OVS there due to duplicate symbols.  That's why we have the checksum and vlan files directly in the main source directory even though they are strictly compatibility code.  So we should only have things that are upstream or we plan to propose upstream here.  In retrospect, we should do this for the genl_exec() stuff as well.