Hello, On Fri, 22 Apr 2011, Hans Schillstrom wrote: > Hello Julian > > >From what I can see there is nothing in the rs_table except for NAT:ed dest, or ? > so the code fragment below will not work. > > I.e. my double list_for_each that goes throug the service table must be there... > or do we need both? Yes, I now see that dests are added to rs_table only for NAT. So, we have no choice, we have to walk svc->destinations. To remove usage of dest_trash in ip_vs_dst_event we can move the ip_vs_dst_reset call in __ip_vs_del_dest() above the atomic_dec_and_test check. But it is not a safe operation. While with svc->usecnt we know if packet accesses the svc, the same for dest is not possible. Packet can hit existing connection (without searching for svc), conn has reference to dest, so the packet can refresh dest->dst_cache at any point of time, eg. while we move dest to trash. That is why __ip_vs_del_dest calls ip_vs_dst_reset only when dest->refcnt reaches 0, i.e. when no conn refers to dest. So, even if we call ip_vs_dst_reset() before the atomic_dec_and_test check, it is still possible some packet to attach new dst_cache entry. As result, we can not assume that dests in trash have no dst_cache entry. So, ip_vs_dst_event() needs to walk both svc->destinations and ipvs->dest_trash under mutex lock. Regards -- Julian Anastasov <ja@xxxxxx> -- To unsubscribe from this list: send the line "unsubscribe lvs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
