Commit Graph

61 Commits

Author SHA1 Message Date
stephen hemminger
4f70c96ffd tcp: make nla_policy const
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 14:09:01 -07:00
Nicolas Dichtel
2175d87cc3 libnl: nla_put_msecs(): align on a 64-bit area
nla_data() is now aligned on a 64-bit area.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-23 20:13:24 -04:00
David S. Miller
810813c47a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, as well as one instance
(vxlan) of a bug fix in 'net' overlapping with code movement
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08 12:34:12 -05:00
Konstantin Khlebnikov
9bdfb3b79e tcp: convert cached rtt from usec to jiffies when feeding initial rto
Currently it's converted into msecs, thus HZ=1000 intact.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Fixes: 740b0f1841 ("tcp: switch rtt estimations to usec resolution")
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-23 18:28:46 -05:00
Nikolay Borisov
1043e25ff9 ipv4: Namespaceify tcp reordering sysctl knob
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-07 14:35:10 -05:00
David Ahern
d39d14ffa2 net: Add helper function to compare inetpeer addresses
tcp_metrics and inetpeer both have functions to compare inetpeer
addresses. Consolidate into 1 version.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 13:32:36 -07:00
David Ahern
3abef286cf net: Add set,get helpers for inetpeer addresses
Use inetpeer set,get helpers in tcp_metrics rather than peeking into
the inetpeer_addr struct.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 13:32:36 -07:00
David Ahern
72afa352d6 net: Introduce ipv4_addr_hash and use it for tcp metrics
Refactors a common line into helper function.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 13:32:35 -07:00
Yuchung Cheng
071d5080e3 tcp: add tcp_in_slow_start helper
Add a helper to test the slow start condition in various congestion
control modules and other places. This is to prepare a slight improvement
in policy as to exactly when to slow start.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 14:22:52 -07:00
Daniel Lee
2646c831c0 tcp: RFC7413 option support for Fast Open client
Fast Open has been using an experimental option with a magic number
(RFC6994). This patch makes the client by default use the RFC7413
option (34) to get and send Fast Open cookies.  This patch makes
the client solicit cookies from a given server first with the
RFC7413 option. If that fails to elicit a cookie, then it tries
the RFC6994 experimental option. If that also fails, it uses the
RFC7413 option on all subsequent connect attempts.  If the server
returns a Fast Open cookie then the client caches the form of the
option that successfully elicited a cookie, and uses that form on
later connects when it presents that cookie.

The idea is to gradually obsolete the use of experimental options as
the servers and clients upgrade, while keeping the interoperability
meanwhile.

Signed-off-by: Daniel Lee <Longinus00@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-07 18:36:39 -04:00
Ian Morris
51456b2914 ipv4: coding style: comparison for equality with NULL
The ipv4 code uses a mixture of coding styles. In some instances check
for NULL pointer is done as x == NULL and sometimes as !x. !x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03 12:11:15 -04:00
Jiri Benc
67b61f6c13 netlink: implement nla_get_in_addr and nla_get_in6_addr
Those are counterparts to nla_put_in_addr and nla_put_in6_addr.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Jiri Benc
930345ea63 netlink: implement nla_put_in_addr and nla_put_in6_addr
IP addresses are often stored in netlink attributes. Add generic functions
to do that.

For nla_put_in_addr, it would be nicer to pass struct in_addr but this is
not used universally throughout the kernel, in way too many places __be32 is
used to store IPv4 address.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Jiri Benc
8f55db4860 tcp: simplify inetpeer_addr_base use
In many places, the a6 field is typecasted to struct in6_addr. As the
fields are in union anyway, just add in6_addr type to the union and get rid
of the typecasting.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Eric Dumazet
9f1ab18672 tcp_metrics: fix wrong lockdep annotations
Changes in tcp_metric hash table are protected by tcp_metrics_lock
only, not by genl_mutex

While we are at it use deref_locked() instead of rcu_dereference()
in tcp_new() to avoid unnecessary barrier, as we hold tcp_metrics_lock
as well.

Reported-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 098a697b49 ("tcp_metrics: Use a single hash table for all network namespaces.")
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-16 16:32:23 -04:00
Eric W. Biederman
098a697b49 tcp_metrics: Use a single hash table for all network namespaces.
Now that all of the operations are safe on a single hash table
accross network namespaces, allocate a single global hash table
and update the code to use it.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13 01:57:07 -04:00
Eric W. Biederman
04f721c671 tcp_metrics: Rewrite tcp_metrics_flush_all
Rewrite tcp_metrics_flush_all so that it can cope with entries from
different network namespaces on it's hash chain.

This is based on the logic in tcp_metrics_nl_cmd_del for deleting
a selection of entries from a tcp metrics hash chain.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13 01:57:07 -04:00
Eric W. Biederman
8a4bff714f tcp_metrics: Remove the unused return code from tcp_metrics_flush_all
tcp_metrics_flush_all always returns 0.  Remove the unnecessary return code.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13 01:57:07 -04:00
Eric W. Biederman
849e8a0ca8 tcp_metrics: Add a field tcpm_net and verify it matches on lookup
In preparation for using one tcp metrics hash table for all network
namespaces add a field tcpm_net to struct tcp_metrics_block, and
verify that field on all hash table lookups.

Make the field tcpm_net of type possible_net_t so it takes no space
when network namespaces are disabled.

Further add a function tm_net to read that field so we can be
efficient when network namespaces are disabled and concise
the rest of the time.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13 01:57:07 -04:00
Eric W. Biederman
3e5da62d0b tcp_metrics: Mix the network namespace into the hash function.
In preparation for using one hash table for all network namespaces
mix the network namespace into the hash value.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13 01:57:07 -04:00
Eric W. Biederman
6493517eae tcp_metrics: panic when tcp_metrics_init fails.
There is not a practical way to cleanup during boot so
just panic if there is a problem initializing tcp_metrics.

That will at least give us a clear place to start debugging
if something does go wrong.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-13 01:57:07 -04:00
Johannes Berg
053c095a82 netlink: make nlmsg_end() and genlmsg_end() void
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18 01:03:45 -05:00
Hannes Frederic Sowa
a26552afe8 tcp: don't allow syn packets without timestamps to pass tcp_tw_recycle logic
tcp_tw_recycle heavily relies on tcp timestamps to build a per-host
ordering of incoming connections and teardowns without the need to
hold state on a specific quadruple for TCP_TIMEWAIT_LEN, but only for
the last measured RTO. To do so, we keep the last seen timestamp in a
per-host indexed data structure and verify if the incoming timestamp
in a connection request is strictly greater than the saved one during
last connection teardown. Thus we can verify later on that no old data
packets will be accepted by the new connection.

During moving a socket to time-wait state we already verify if timestamps
where seen on a connection. Only if that was the case we let the
time-wait socket expire after the RTO, otherwise normal TCP_TIMEWAIT_LEN
will be used. But we don't verify this on incoming SYN packets. If a
connection teardown was less than TCP_PAWS_MSL seconds in the past we
cannot guarantee to not accept data packets from an old connection if
no timestamps are present. We should drop this SYN packet. This patch
closes this loophole.

Please note, this patch does not make tcp_tw_recycle in any way more
usable but only adds another safety check:
Sporadic drops of SYN packets because of reordering in the network or
in the socket backlog queues can happen. Users behing NAT trying to
connect to a tcp_tw_recycle enabled server can get caught in blackholes
and their connection requests may regullary get dropped because hosts
behind an address translator don't have synchronized tcp timestamp clocks.
tcp_tw_recycle cannot work if peers don't have tcp timestamps enabled.

In general, use of tcp_tw_recycle is disadvised.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14 14:38:54 -07:00
Banerjee, Debabrata
388070faa1 tcp: don't require root to read tcp_metrics
commit d23ff7016 (tcp: add generic netlink support for tcp_metrics) introduced
netlink support for the new tcp_metrics, however it restricted getting of
tcp_metrics to root user only. This is a change from how these values could
have been fetched when in the old route cache. Unless there's a legitimate
reason to restrict the reading of these values it would be better if normal
users could fetch them.

Cc: Julian Anastasov <ja@ssi.bg>
Cc: linux-kernel@vger.kernel.org

Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-31 14:07:37 -07:00
WANG Cong
4cb28970a2 net: use the new API kvfree()
It is available since v3.15-rc5.

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-05 00:49:51 -07:00
Eric Dumazet
740b0f1841 tcp: switch rtt estimations to usec resolution
Upcoming congestion controls for TCP require usec resolution for RTT
estimations. Millisecond resolution is simply not enough these days.

FQ/pacing in DC environments also require this change for finer control
and removal of bimodal behavior due to the current hack in
tcp_update_pacing_rate() for 'small rtt'

TCP_CONG_RTT_STAMP is no longer needed.

As Julian Anastasov pointed out, we need to keep user compatibility :
tcp_metrics used to export RTT and RTTVAR in msec resolution,
so we added RTT_US and RTTVAR_US. An iproute2 patch is needed
to use the new attributes if provided by the kernel.

In this example ss command displays a srtt of 32 usecs (10Gbit link)

lpk51:~# ./ss -i dst lpk52
Netid  State      Recv-Q Send-Q   Local Address:Port       Peer
Address:Port
tcp    ESTAB      0      1         10.246.11.51:42959
10.246.11.52:64614
         cubic wscale:6,6 rto:201 rtt:0.032/0.001 ato:40 mss:1448
cwnd:10 send
3620.0Mbps pacing_rate 7240.0Mbps unacked:1 rcv_rtt:993 rcv_space:29559

Updated iproute2 ip command displays :

lpk51:~# ./ip tcp_metrics | grep 10.246.11.52
10.246.11.52 age 561.914sec cwnd 10 rtt 274us rttvar 213us source
10.246.11.51

Old binary displays :

lpk51:~# ip tcp_metrics | grep 10.246.11.52
10.246.11.52 age 561.914sec cwnd 10 rtt 250us rttvar 125us source
10.246.11.51

With help from Julian Anastasov, Stephen Hemminger and Yuchung Cheng

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Larry Brakmo <brakmo@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-26 17:08:40 -05:00
Christoph Paasch
3ad88cf70a tcp: metrics: Handle v6/v4-mapped sockets in tcp-metrics
A socket may be v6/v4-mapped. In that case sk->sk_family is AF_INET6,
but the IP being used is actually an IPv4-address.
Current's tcp-metrics will thus represent it as an IPv6-address:

root@server:~# ip tcp_metrics
::ffff:10.1.1.2 age 22.920sec rtt 18750us rttvar 15000us cwnd 10
10.1.1.2 age 47.970sec rtt 16250us rttvar 10000us cwnd 10

This patch modifies the tcp-metrics so that they are able to handle the
v6/v4-mapped sockets correctly.

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-23 12:48:28 -08:00
Christoph Paasch
00ca9c5b2b tcp: metrics: Fix rcu-race when deleting multiple entries
In bbf852b96e I introduced the tmlist, which allows to delete
multiple entries from the cache that match a specified destination if no
source-IP is specified.

However, as the cache is an RCU-list, we should not create this tmlist, as
it will change the tcpm_next pointer of the element that will be deleted
and so a thread iterating over the cache's entries while holding the
RCU-lock might get "redirected" to this tmlist.

This patch fixes this, by reverting back to the old behavior prior to
bbf852b96e, which means that we simply change the tcpm_next
pointer of the previous element (pp) to jump over the one we are
deleting.
The difference is that we call kfree_rcu() directly on the cache entry,
which allows us to delete multiple entries from the list.

Fixes: bbf852b96e (tcp: metrics: Delete all entries matching a certain destination)
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 21:26:16 -08:00
David S. Miller
4180442058 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
	net/ipv4/tcp_metrics.c

Overlapping changes between the "don't create two tcp metrics objects
with the same key" race fix in net and the addition of the destination
address in the lookup key in net-next.

Minor overlapping changes in bnx2x driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-18 00:55:41 -08:00
Christoph Paasch
77f99ad16a tcp: metrics: Avoid duplicate entries with the same destination-IP
Because the tcp-metrics is an RCU-list, it may be that two
soft-interrupts are inside __tcp_get_metrics() for the same
destination-IP at the same time. If this destination-IP is not yet part of
the tcp-metrics, both soft-interrupts will end up in tcpm_new and create
a new entry for this IP.
So, we will have two tcp-metrics with the same destination-IP in the list.

This patch checks twice __tcp_get_metrics(). First without holding the
lock, then while holding the lock. The second one is there to confirm
that the entry has not been added by another soft-irq while waiting for
the spin-lock.

Fixes: 51c5d0c4b1 (tcp: Maintain dynamic metrics in local cache.)
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 18:05:34 -08:00
Christoph Paasch
3e7013ddf5 tcp: metrics: Allow selective get/del of tcp-metrics based on src IP
We want to be able to get/del tcp-metrics based on the src IP. This
patch adds the necessary parsing of the netlink attribute and if the
source address is set, it will match on this one too.

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 17:38:18 -05:00
Christoph Paasch
bbf852b96e tcp: metrics: Delete all entries matching a certain destination
As we now can have multiple entries per destination-IP, the "ip
tcp_metrics delete address ADDRESS" command deletes all of them.

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 17:38:18 -05:00
Christoph Paasch
8a59359cb8 tcp: metrics: New netlink attribute for src IP and dumped in netlink reply
This patch adds a new netlink attribute for the source-IP and appends it
to the netlink reply. Now, iproute2 can have access to the source-IP.

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 17:38:18 -05:00
Christoph Paasch
a544302820 tcp: metrics: Add source-address to tcp-metrics
We add the source-address to the tcp-metrics, so that different metrics
will be used per source/destination-pair. We use the destination-hash to
store the metric inside the hash-table. That way, deleting and dumping
via "ip tcp_metrics" is easy.

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 17:38:18 -05:00
Christoph Paasch
324fd55a19 tcp: metrics: rename tcpm_addr to tcpm_daddr
As we will add also the source-address, we rename all accesses to the
tcp-metrics address to use "daddr".

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 17:38:18 -05:00
Johannes Berg
c53ed74236 genetlink: only pass array to genl_register_family_with_ops()
As suggested by David Miller, make genl_register_family_with_ops()
a macro and pass only the array, evaluating ARRAY_SIZE() in the
macro, this is a little safer.

The openvswitch has some indirection, assing ops/n_ops directly in
that code. This might ultimately just assign the pointers in the
family initializations, saving the struct genl_family_and_ops and
code (once mcast groups are handled differently.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 16:39:05 -05:00
Johannes Berg
4534de8305 genetlink: make all genl_ops users const
Now that genl_ops are no longer modified in place when
registering, they can be made const. This patch was done
mostly with spatch:

@@
identifier ops;
@@
+const
 struct genl_ops ops[] = {
 ...
 };

(except the struct thing in net/openvswitch/datapath.c)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14 17:10:41 -05:00
Eric Dumazet
dccf76ca6b net-tcp: fix panic in tcp_fastopen_cache_set()
We had some reports of crashes using TCP fastopen, and Dave Jones
gave a nice stack trace pointing to the error.

Issue is that tcp_get_metrics() should not be called with a NULL dst

Fixes: 1fe4c481ba ("net-tcp: Fast Open client - cookie cache")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dave Jones <davej@redhat.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Tested-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14 16:33:18 -05:00
Yuchung Cheng
c968601d17 tcp: temporarily disable Fast Open on SYN timeout
Fast Open currently has a fall back feature to address SYN-data being
dropped but it requires the middle-box to pass on regular SYN retry
after SYN-data. This is implemented in commit aab487435 ("net-tcp:
Fast Open client - detecting SYN-data drops")

However some NAT boxes will drop all subsequent packets after first
SYN-data and blackholes the entire connections.  An example is in
commit 356d7d8 "netfilter: nf_conntrack: fix tcp_in_window for Fast
Open".

The sender should note such incidents and fall back to use the regular
TCP handshake on subsequent attempts temporarily as well: after the
second SYN timeouts the original Fast Open SYN is most likely lost.
When such an event recurs Fast Open is disabled based on the number of
recurrences exponentially.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-29 22:50:41 -04:00
Eric Dumazet
634fb979e8 inet: includes a sock_common in request_sock
TCP listener refactoring, part 5 :

We want to be able to insert request sockets (SYN_RECV) into main
ehash table instead of the per listener hash table to allow RCU
lookups and remove listener lock contention.

This patch includes the needed struct sock_common in front
of struct request_sock

This means there is no more inet6_request_sock IPv6 specific
structure.

Following inet_request_sock fields were renamed as they became
macros to reference fields from struct sock_common.
Prefix ir_ was chosen to avoid name collisions.

loc_port   -> ir_loc_port
loc_addr   -> ir_loc_addr
rmt_addr   -> ir_rmt_addr
rmt_port   -> ir_rmt_port
iif        -> ir_iif

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-10 00:08:07 -04:00
Eric Dumazet
c2bb06db59 net: fix build errors if ipv6 is disabled
CONFIG_IPV6=n is still a valid choice ;)

It appears we can remove dead code.

Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-09 13:04:03 -04:00
Eric Dumazet
efe4208f47 ipv6: make lookups simpler and faster
TCP listener refactoring, part 4 :

To speed up inet lookups, we moved IPv4 addresses from inet to struct
sock_common

Now is time to do the same for IPv6, because it permits us to have fast
lookups for all kind of sockets, including upcoming SYN_RECV.

Getting IPv6 addresses in TCP lookups currently requires two extra cache
lines, plus a dereference (and memory stall).

inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6

This patch is way bigger than its IPv4 counter part, because for IPv4,
we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6,
it's not doable easily.

inet6_sk(sk)->daddr becomes sk->sk_v6_daddr
inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr

And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr
at the same offset.

We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic
macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-09 00:01:25 -04:00
Neal Cardwell
269aa759b4 tcp: fix RTO calculated from cached RTT
Commit 1b7fdd2ab5 ("tcp: do not use cached RTT for RTT estimation")
did not correctly account for the fact that crtt is the RTT shifted
left 3 bits. Fix the calculation to consistently reflect this fact.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-By: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-17 19:08:08 -04:00
Yuchung Cheng
52f20e655d tcp: better comments for RTO initiallization
Commit 1b7fdd2ab585("tcp: do not use cached RTT for RTT estimation")
removes important comments on how RTO is initialized and updated.
Hopefully this patch puts those information back.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 14:41:55 -04:00
Yuchung Cheng
1b7fdd2ab5 tcp: do not use cached RTT for RTT estimation
RTT cached in the TCP metrics are valuable for the initial timeout
because SYN RTT usually does not account for serialization delays
on low BW path.

However using it to seed the RTT estimator maybe disruptive because
other components (e.g., pacing) require the smooth RTT to be obtained
from actual connection.

The solution is to use the higher cached RTT to set the first RTO
conservatively like tcp_rtt_estimator(), but avoid seeding the other
RTT estimator variables such as srtt.  It is also a good idea to
keep RTO conservative to obtain the first RTT sample, and the
performance is insured by TCP loss probe if SYN RTT is available.

To keep the seeding formula consistent across SYN RTT and cached RTT,
the rttvar is twice the cached RTT instead of cached RTTVAR value. The
reason is because cached variation may be too small (near min RTO)
which defeats the purpose of being conservative on first RTO. However
the metrics still keep the RTT variations as they might be useful for
user applications (through ip).

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-30 15:14:38 -04:00
Eric Dumazet
efeaa5550e tcp: do not expire TCP fastopen cookies
TCP metric cache expires entries after one hour.

This probably make sense for TCP RTT/RTTVAR/CWND, but not
for TCP fastopen cookies.

Its better to try previous cookie. If it appears to be obsolete,
server will send us new cookie anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-05 16:58:02 -04:00
Eric Dumazet
976a702ac9 tcp: handle tcp_net_metrics_init() order-5 memory allocation failures
order-5 allocations can fail with current kernels, we should
try vmalloc() as well.

Reported-by: Julien Tinnes <jln@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-16 13:36:27 -05:00
Julian Anastasov
2c42a3fb30 tcp: Fix double sizeof in new tcp_metrics code
Fix double sizeof when parsing IPv6 address from
user space because it breaks get/del by specific IPv6 address.

	Problem noticed by David Binderman:

https://bugzilla.kernel.org/show_bug.cgi?id=49171

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-01 11:59:08 -04:00
Eric W. Biederman
15e473046c netlink: Rename pid to portid to avoid confusion
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>
2012-09-10 15:30:41 -04:00
Julian Anastasov
d23ff70164 tcp: add generic netlink support for tcp_metrics
Add support for genl "tcp_metrics". No locking
is changed, only that now we can unlink and delete
entries after grace period. We implement get/del for
single entry and dump to support show/flush filtering
in user space. Del without address attribute causes
flush for all addresses, sadly under genl_mutex.

v2:
- remove rcu_assign_pointer as suggested by Eric Dumazet,
it is not needed because there are no other writes under lock
- move the flushing code in tcp_metrics_flush_all

v3:
- remove synchronize_rcu on flush as suggested by Eric Dumazet

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-05 15:15:02 -04:00