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| * netns: move net->ipv4.rt_genid to net->rt_genidNicolas Dichtel2012-09-181-7/+2
| | | | | | | | | | | | | | | | This commit prepares the use of rt_genid by both IPv4 and IPv6. Initialization is left in IPv4 part. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: rt_cache_flush() cleanupEric Dumazet2012-09-181-17/+2
| | | | | | | | | | | | | | | | | | We dont use jhash anymore since route cache removal, so we can get rid of get_random_bytes() calls for rt_genid changes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4/route: arg delay is useless in rt_cache_flush()Nicolas Dichtel2012-09-181-16/+3
| | | | | | | | | | | | | | | | | | Since route cache deletion (89aef8921bfbac22f), delay is no more used. Remove it. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | netlink: Rename pid to portid to avoid confusionEric W. Biederman2012-09-101-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is a frequent mistake to confuse the netlink port identifier with a process identifier. Try to reduce this confusion by renaming fields that hold port identifiers portid instead of pid. I have carefully avoided changing the structures exported to userspace to avoid changing the userspace API. I have successfully built an allyesconfig kernel with this change. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: rt_cache_flush() cleanupEric Dumazet2012-09-071-17/+2
| | | | | | | | | | | | | | | | | | We dont use jhash anymore since route cache removal, so we can get rid of get_random_bytes() calls for rt_genid changes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4/route: arg delay is useless in rt_cache_flush()Nicolas Dichtel2012-09-071-16/+3
| | | | | | | | | | | | | | | | | | Since route cache deletion (89aef8921bfbac22f), delay is no more used. Remove it. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4: Minor logic clean-up in ipv4_mtuAlexander Duyck2012-08-311-4/+1
| | | | | | | | | | | | | | | | | | | | | | In ipv4_mtu there is some logic where we are testing for a non-zero value and a timer expiration, then setting the value to zero, and then testing if the value is zero we set it to a value based on the dst. Instead of bothering with the extra steps it is easier to just cleanup the logic so that we set it to the dst based value if it is zero or if the timer has expired. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2012-08-311-2/+4
|\ \ | |/ | | | | | | | | | | | | Merge the 'net' tree to get the recent set of netfilter bug fixes in order to assist with some merge hassles Pablo is going to have to deal with for upcoming changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: must use rcu protection while calling fib_lookupEric Dumazet2012-08-301-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Following lockdep splat was reported by Pavel Roskin : [ 1570.586223] =============================== [ 1570.586225] [ INFO: suspicious RCU usage. ] [ 1570.586228] 3.6.0-rc3-wl-main #98 Not tainted [ 1570.586229] ------------------------------- [ 1570.586231] /home/proski/src/linux/net/ipv4/route.c:645 suspicious rcu_dereference_check() usage! [ 1570.586233] [ 1570.586233] other info that might help us debug this: [ 1570.586233] [ 1570.586236] [ 1570.586236] rcu_scheduler_active = 1, debug_locks = 0 [ 1570.586238] 2 locks held by Chrome_IOThread/4467: [ 1570.586240] #0: (slock-AF_INET){+.-...}, at: [<ffffffff814f2c0c>] release_sock+0x2c/0xa0 [ 1570.586253] #1: (fnhe_lock){+.-...}, at: [<ffffffff815302fc>] update_or_create_fnhe+0x2c/0x270 [ 1570.586260] [ 1570.586260] stack backtrace: [ 1570.586263] Pid: 4467, comm: Chrome_IOThread Not tainted 3.6.0-rc3-wl-main #98 [ 1570.586265] Call Trace: [ 1570.586271] [<ffffffff810976ed>] lockdep_rcu_suspicious+0xfd/0x130 [ 1570.586275] [<ffffffff8153042c>] update_or_create_fnhe+0x15c/0x270 [ 1570.586278] [<ffffffff815305b3>] __ip_rt_update_pmtu+0x73/0xb0 [ 1570.586282] [<ffffffff81530619>] ip_rt_update_pmtu+0x29/0x90 [ 1570.586285] [<ffffffff815411dc>] inet_csk_update_pmtu+0x2c/0x80 [ 1570.586290] [<ffffffff81558d1e>] tcp_v4_mtu_reduced+0x2e/0xc0 [ 1570.586293] [<ffffffff81553bc4>] tcp_release_cb+0xa4/0xb0 [ 1570.586296] [<ffffffff814f2c35>] release_sock+0x55/0xa0 [ 1570.586300] [<ffffffff815442ef>] tcp_sendmsg+0x4af/0xf50 [ 1570.586305] [<ffffffff8156fc60>] inet_sendmsg+0x120/0x230 [ 1570.586308] [<ffffffff8156fb40>] ? inet_sk_rebuild_header+0x40/0x40 [ 1570.586312] [<ffffffff814f4bdd>] ? sock_update_classid+0xbd/0x3b0 [ 1570.586315] [<ffffffff814f4c50>] ? sock_update_classid+0x130/0x3b0 [ 1570.586320] [<ffffffff814ec435>] do_sock_write+0xc5/0xe0 [ 1570.586323] [<ffffffff814ec4a3>] sock_aio_write+0x53/0x80 [ 1570.586328] [<ffffffff8114bc83>] do_sync_write+0xa3/0xe0 [ 1570.586332] [<ffffffff8114c5a5>] vfs_write+0x165/0x180 [ 1570.586335] [<ffffffff8114c805>] sys_write+0x45/0x90 [ 1570.586340] [<ffffffff815d2722>] system_call_fastpath+0x16/0x1b Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Pavel Roskin <proski@gnu.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: take rt_uncached_lock only if neededEric Dumazet2012-08-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Multicast traffic allocates dst with DST_NOCACHE, but dst is not inserted into rt_uncached_list. This slowdown multicast workloads on SMP because rt_uncached_lock is contended. Change the test before taking the lock to actually check the dst was inserted into rt_uncached_list. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: properly update pmtuEric Dumazet2012-08-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sylvain Munault reported following info : - TCP connection get "stuck" with data in send queue when doing "large" transfers ( like typing 'ps ax' on a ssh connection ) - Only happens on path where the PMTU is lower than the MTU of the interface - Is not present right after boot, it only appears 10-20min after boot or so. (and that's inside the _same_ TCP connection, it works fine at first and then in the same ssh session, it'll get stuck) - Definitely seems related to fragments somehow since I see a router sending ICMP message saying fragmentation is needed. - Exact same setup works fine with kernel 3.5.1 Problem happens when the 10 minutes (ip_rt_mtu_expires) expiration period is over. ip_rt_update_pmtu() calls dst_set_expires() to rearm a new expiration, but dst_set_expires() does nothing because dst.expires is already set. It seems we want to set the expires field to a new value, regardless of prior one. With help from Julian Anastasov. Reported-by: Sylvain Munaut <s.munaut@whatever-company.com> Signed-off-by: Eric Dumazet <edumazet@google.com> CC: Julian Anastasov <ja@ssi.bg> Tested-by: Sylvain Munaut <s.munaut@whatever-company.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2012-08-221-1/+0
|\ \ | |/
| * ipv4: Cache local output routesYan, Zheng2012-08-141-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | Commit caacf05e5ad1abf causes big drop of UDP loop back performance. The cause of the regression is that we do not cache the local output routes. Each time we send a datagram from unconnected UDP socket, the kernel allocates a dst_entry and adds it to the rt_uncached_list. It creates lock contention on the rt_uncached_lock. Reported-by: Alex Shi <alex.shi@intel.com> Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: Loopback ifindex is constant nowPavel Emelyanov2012-08-091-3/+3
| | | | | | | | | | | | | | | | | | | | | | As pointed out, there are places, that access net->loopback_dev->ifindex and after ifindex generation is made per-net this value becomes constant equals 1. So go ahead and introduce the LOOPBACK_IFINDEX constant and use it where appropriate. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4: Introduce IN_DEV_NET_ROUTE_LOCALNETEric Dumazet2012-08-041-4/+7
|/ | | | | | | | | | | | | | | | performance profiles show a high cost in the IN_DEV_ROUTE_LOCALNET() call done in ip_route_input_slow(), because of multiple dereferences, even if cache lines are clean and available in cpu caches. Since we already have the 'net' pointer, introduce IN_DEV_NET_ROUTE_LOCALNET() macro avoiding two dereferences (dev_net(in_dev->dev)) Also change the tests to use IN_DEV_NET_ROUTE_LOCALNET() only if saddr or/and daddr are loopback addresse. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: route.c cleanupEric Dumazet2012-08-021-4/+0
| | | | | | | Remove unused includes after IP cache removal Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Properly purge netdev references on uncached routes.David S. Miller2012-07-311-4/+64
| | | | | | | | | | | | | When a device is unregistered, we have to purge all of the references to it that may exist in the entire system. If a route is uncached, we currently have no way of accomplishing this. So create a global list that is scanned when a network device goes down. This mirrors the logic in net/core/dst.c's dst_ifdown(). Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Cache routes in nexthop exception entries.David S. Miller2012-07-311-46/+57
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: percpu nh_rth_output cacheEric Dumazet2012-07-311-5/+13
| | | | | | | | | | | | | | | | | | | | | | Input path is mostly run under RCU and doesnt touch dst refcnt But output path on forwarding or UDP workloads hits badly dst refcount, and we have lot of false sharing, for example in ipv4_mtu() when reading rt->rt_pmtu Using a percpu cache for nh_rth_output gives a nice performance increase at a small cost. 24 udpflood test on my 24 cpu machine (dummy0 output device) (each process sends 1.000.000 udp frames, 24 processes are started) before : 5.24 s after : 2.06 s For reference, time on linux-3.5 : 6.60 s Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Restore old dst_free() behavior.Eric Dumazet2012-07-311-9/+17
| | | | | | | | | | | | | | | | | | | | | | | commit 404e0a8b6a55 (net: ipv4: fix RCU races on dst refcounts) tried to solve a race but added a problem at device/fib dismantle time : We really want to call dst_free() as soon as possible, even if sockets still have dst in their cache. dst_release() calls in free_fib_info_rcu() are not welcomed. Root of the problem was that now we also cache output routes (in nh_rth_output), we must use call_rcu() instead of call_rcu_bh() in rt_free(), because output route lookups are done in process context. Based on feedback and initial patch from David Miller (adding another call_rcu_bh() call in fib, but it appears it was not the right fix) I left the inet_sk_rx_dst_set() helper and added __rcu attributes to nh_rth_output and nh_rth_input to better document what is going on in this code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: ipv4: fix RCU races on dst refcountsEric Dumazet2012-07-301-12/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c6cffba4ffa2 (ipv4: Fix input route performance regression.) added various fatal races with dst refcounts. crashes happen on tcp workloads if routes are added/deleted at the same time. The dst_free() calls from free_fib_info_rcu() are clearly racy. We need instead regular dst refcounting (dst_release()) and make sure dst_release() is aware of RCU grace periods : Add DST_RCU_FREE flag so that dst_release() respects an RCU grace period before dst destruction for cached dst Introduce a new inet_sk_rx_dst_set() helper, using atomic_inc_not_zero() to make sure we dont increase a zero refcount (On a dst currently waiting an rcu grace period before destruction) rt_cache_route() must take a reference on the new cached route, and release it if was not able to install it. With this patch, my machines survive various benchmarks. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Fix input route performance regression.David S. Miller2012-07-261-26/+22
| | | | | | | | | | | | | | | With the routing cache removal we lost the "noref" code paths on input, and this can kill some routing workloads. Reinstate the noref path when we hit a cached route in the FIB nexthops. With help from Eric Dumazet. Reported-by: Alexander Duyck <alexander.duyck@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: rt_cache_valid must check expired routesEric Dumazet2012-07-251-3/+5
| | | | | | | | | | | commit d2d68ba9fe8 (ipv4: Cache input routes in fib_info nexthops.) introduced rt_cache_valid() helper. It unfortunately doesn't check if route is expired before caching it. I noticed sk_setup_caps() was constantly called on a tcp workload. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Change rt->rt_iif encoding.David S. Miller2012-07-231-4/+4
| | | | | | | | | | On input packet processing, rt->rt_iif will be zero if we should use skb->dev->ifindex. Since we access rt->rt_iif consistently via inet_iif(), that is the only spot whose interpretation have to adjust. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Prepare for change of rt->rt_iif encoding.David S. Miller2012-07-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | Use inet_iif() consistently, and for TCP record the input interface of cached RX dst in inet sock. rt->rt_iif is going to be encoded differently, so that we can legitimately cache input routes in the FIB info more aggressively. When the input interface is "use SKB device index" the rt->rt_iif will be set to zero. This forces us to move the TCP RX dst cache installation into the ipv4 specific code, and as well it should since doing the route caching for ipv6 is pointless at the moment since it is not inspected in the ipv6 input paths yet. Also, remove the unlikely on dst->obsolete, all ipv4 dsts have obsolete set to a non-zero value to force invocation of the check callback. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Remove all RTCF_DIRECTSRC handliing.David S. Miller2012-07-231-9/+2
| | | | | | | The last and final kernel user, ICMP address replies, has been removed. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Kill rt->fiDavid S. Miller2012-07-201-31/+1
| | | | | | | | | | | | | | | | | | | It's not really needed. We only grabbed a reference to the fib_info for the sake of fib_info local metrics. However, fib_info objects are freed using RCU, as are therefore their private metrics (if any). We would have triggered a route cache flush if we eliminated a reference to a fib_info object in the routing tables. Therefore, any existing cached routes will first check and see that they have been invalidated before an errant reference to these metric values would occur. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Turn rt->rt_route_iif into rt->rt_is_input.David S. Miller2012-07-201-5/+5
| | | | | | | | | | That is this value's only use, as a boolean to indicate whether a route is an input route or not. So implement it that way, using a u16 gap present in the struct already. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Kill rt->rt_oifDavid S. Miller2012-07-201-5/+0
| | | | | | | | | | | | | Never actually used. It was being set on output routes to the original OIF specified in the flow key used for the lookup. Adjust the only user, ipmr_rt_fib_lookup(), for greater correctness of the flowi4_oif and flowi4_iif values, thanks to feedback from Julian Anastasov. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Dirty less cache lines in route caching paths.David S. Miller2012-07-201-3/+3
| | | | | | | Don't bother incrementing dst->__use and setting dst->lastuse, they are completely pointless and just slow things down. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Kill FLOWI_FLAG_RT_NOCACHE and associated code.David S. Miller2012-07-201-3/+0
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Cache input routes in fib_info nexthops.David S. Miller2012-07-201-12/+43
| | | | | | | | | | | | Caching input routes is slightly simpler than output routes, since we don't need to be concerned with nexthop exceptions. (locally destined, and routed packets, never trigger PMTU events or redirects that will be processed by us). However, we have to elide caching for the DIRECTSRC and non-zero itag cases. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Cache output routes in fib_info nexthops.David S. Miller2012-07-201-43/+97
| | | | | | | | | | | | | | | | | | | | | | | If we have an output route that lacks nexthop exceptions, we can cache it in the FIB info nexthop. Such routes will have DST_HOST cleared because such routes refer to a family of destinations, rather than just one. The sequence of the handling of exceptions during route lookup is adjusted to make the logic work properly. Before we allocate the route, we lookup the exception. Then we know if we will cache this route or not, and therefore whether DST_HOST should be set on the allocated route. Then we use DST_HOST to key off whether we should store the resulting route, during rt_set_nexthop(), in the FIB nexthop cache. With help from Eric Dumazet. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Kill routes during PMTU/redirect updates.David S. Miller2012-07-201-12/+29
| | | | | | | Mark them obsolete so there will be a re-lookup to fetch the FIB nexthop exception info. Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Document dst->obsolete better.David S. Miller2012-07-201-2/+3
| | | | | | | | | Add a big comment explaining how the field works, and use defines instead of magic constants for the values assigned to it. Suggested by Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Adjust semantics of rt->rt_gateway.David S. Miller2012-07-201-8/+9
| | | | | | | | | | | | | | | | | In order to allow prefixed routes, we have to adjust how rt_gateway is set and interpreted. The new interpretation is: 1) rt_gateway == 0, destination is on-link, nexthop is iph->daddr 2) rt_gateway != 0, destination requires a nexthop gateway Abstract the fetching of the proper nexthop value using a new inline helper, rt_nexthop(), as suggested by Joe Perches. Signed-off-by: David S. Miller <davem@davemloft.net> Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com>
* ipv4: Remove 'rt_dst' from 'struct rtable'David S. Miller2012-07-201-36/+9
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Remove 'rt_mark' from 'struct rtable'David Miller2012-07-201-7/+2
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Kill 'rt_src' from 'struct rtable'David Miller2012-07-201-19/+15
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Remove rt_key_{src,dst,tos} from struct rtable.David Miller2012-07-201-30/+9
| | | | | | | | They are always used in contexts where they can be reconstituted, or where the finally resolved rt->rt_{src,dst} is semantically equivalent. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Kill ip_route_input_noref().David Miller2012-07-201-3/+3
| | | | | | | | The "noref" argument to ip_route_input_common() is now always ignored because we do not cache routes, and in that case we must always grab a reference to the resulting 'dst'. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Delete routing cache.David S. Miller2012-07-201-927/+13
| | | | | | | | | | | | | | | | | | | The ipv4 routing cache is non-deterministic, performance wise, and is subject to reasonably easy to launch denial of service attacks. The routing cache works great for well behaved traffic, and the world was a much friendlier place when the tradeoffs that led to the routing cache's design were considered. What it boils down to is that the performance of the routing cache is a product of the traffic patterns seen by a system rather than being a product of the contents of the routing tables. The former of which is controllable by external entitites. Even for "well behaved" legitimate traffic, high volume sites can see hit rates in the routing cache of only ~%10. Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: show pmtu in route listJulian Anastasov2012-07-201-1/+5
| | | | | | | Override the metrics with rt_pmtu Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Fix again the time difference calculationJulian Anastasov2012-07-191-1/+1
| | | | | | | | | Fix again the diff value in rt_bind_exception after collision of two latest patches, my original commit actually fixed the same problem. Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: use seqlock for nh_exceptionsJulian Anastasov2012-07-191-50/+68
| | | | | | | | | | | | | | | | | | Use global seqlock for the nh_exceptions. Call fnhe_oldest with the right hash chain. Correct the diff value for dst_set_expires. v2: after suggestions from Eric Dumazet: * get rid of spin lock fnhe_lock, rearrange update_or_create_fnhe * continue daddr search in rt_bind_exception v3: * remove the daddr check before seqlock in rt_bind_exception * restart lookup in rt_bind_exception on detected seqlock change, as suggested by David Miller Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Fix time difference calculation in rt_bind_exception().David S. Miller2012-07-191-1/+1
| | | | | Reported-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: fix rcu splatEric Dumazet2012-07-171-6/+7
| | | | | | | | | | free_nh_exceptions() should use rcu_dereference_protected(..., 1) since its called after one RCU grace period. Also add some const-ification in recent code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Fix nexthop exception hash computation.David S. Miller2012-07-171-4/+12
| | | | | | Need to mask it with (FNHE_HASH_SIZE - 1). Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Add FIB nexthop exceptions.David S. Miller2012-07-171-31/+225
| | | | | | | | | | | | | | In a regime where we have subnetted route entries, we need a way to store persistent storage about destination specific learned values such as redirects and PMTU values. This is implemented here via nexthop exceptions. The initial implementation is a 2048 entry hash table with relaiming starting at chain length 5. A more sophisticated scheme can be devised if that proves necessary. Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()David S. Miller2012-07-171-8/+13
| | | | | | | | | | | | | | | | This will be used so that we can compose a full flow key. Even though we have a route in this context, we need more. In the future the routes will be without destination address, source address, etc. keying. One ipv4 route will cover entire subnets, etc. In this environment we have to have a way to possess persistent storage for redirects and PMTU information. This persistent storage will exist in the FIB tables, and that's why we'll need to be able to rebuild a full lookup flow key here. Using that flow key will do a fib_lookup() and create/update the persistent entry. Signed-off-by: David S. Miller <davem@davemloft.net>
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