Commit Graph

27 Commits

Author SHA1 Message Date
Daniel Borkmann b9507bdaf4 netdevice: move netdev_cap_txqueue for shared usage to header
In order to allow users to invoke netdev_cap_txqueue, it needs to
be moved into netdevice.h header file. While at it, also add kernel
doc header to document the API.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 00:36:34 -05:00
Daniel Borkmann 99932d4fc0 netdevice: add queue selection fallback handler for ndo_select_queue
Add a new argument for ndo_select_queue() callback that passes a
fallback handler. This gets invoked through netdev_pick_tx();
fallback handler is currently __netdev_pick_tx() as most drivers
invoke this function within their customized implementation in
case for skbs that don't need any special handling. This fallback
handler can then be replaced on other call-sites with different
queue selection methods (e.g. in packet sockets, pktgen etc).

This also has the nice side-effect that __netdev_pick_tx() is
then only invoked from netdev_pick_tx() and export of that
function to modules can be undone.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 00:36:34 -05:00
David S. Miller 0a379e21c5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-01-14 14:42:42 -08:00
Jason Wang f663dd9aaf net: core: explicitly select a txq before doing l2 forwarding
Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The
will cause several issues:

- NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan
  instead of lower device which misses the necessary txq synchronization for
  lower device such as txq stopping or frozen required by dev watchdog or
  control path.
- dev_hard_start_xmit() was called with NULL txq which bypasses the net device
  watchdog.
- dev_hard_start_xmit() does not check txq everywhere which will lead a crash
  when tso is disabled for lower device.

Fix this by explicitly introducing a new param for .ndo_select_queue() for just
selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also
extended to accept this parameter and dev_queue_xmit_accel() was used to do l2
forwarding transmission.

With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need
to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep
a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of
dev_queue_xmit() to do the transmission.

In the future, it was also required for macvtap l2 forwarding support since it
provides a necessary synchronization method.

Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: e1000-devel@lists.sourceforge.net
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 13:23:08 -05:00
Tom Herbert 3958afa1b2 net: Change skb_get_rxhash to skb_get_hash
Changing name of function as part of making the hash in skbuff to be
generic property, not just for receive path.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-17 16:36:21 -05:00
Eric Dumazet 3797d3e846 net: flow_dissector: small optimizations in IPv4 dissect
By moving code around, we avoid :

1) A reload of iph->ihl (bit field, so needs a mask)

2) A conditional test (replaced by a conditional mov on x86)
   Fast path loads iph->protocol anyway.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-08 13:30:02 -05:00
David S. Miller 394efd19d5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/emulex/benet/be.h
	drivers/net/netconsole.c
	net/bridge/br_private.h

Three mostly trivial conflicts.

The net/bridge/br_private.h conflict was a function signature (argument
addition) change overlapping with the extern removals from Joe Perches.

In drivers/net/netconsole.c we had one change adjusting a printk message
whilst another changed "printk(KERN_INFO" into "pr_info(".

Lastly, the emulex change was a new inline function addition overlapping
with Joe Perches's extern removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-04 13:48:30 -05:00
Jason Wang 6f09234385 net: flow_dissector: fail on evil iph->ihl
We don't validate iph->ihl which may lead a dead loop if we meet a IPIP
skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl
is evil (less than 5).

This issue were introduced by commit ec5efe7946
(rps: support IPIP encapsulation).

Cc: Eric Dumazet <edumazet@google.com>
Cc: Petr Matousek <pmatouse@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-02 02:16:07 -04:00
Hannes Frederic Sowa 66415cf8a1 net: initialize hashrnd in flow_dissector with net_get_random_once
We also can defer the initialization of hashrnd in flow_dissector
to its first use. Since net_get_random_once is irq safe now we don't
have to audit the call paths if one of this functions get called by an
interrupt handler.

Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-25 19:03:39 -04:00
Nikolay Aleksandrov 357afe9c46 flow_dissector: factor out the ports extraction in skb_flow_get_ports
Factor out the code that extracts the ports from skb_flow_dissect and
add a new function skb_flow_get_ports which can be re-used.

Suggested-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-03 15:36:37 -04:00
Eric Dumazet b86783587b net: flow_dissector: fix thoff for IPPROTO_AH
In commit 8ed781668d ("flow_keys: include thoff into flow_keys for
later usage"), we missed that existing code was using nhoff as a
temporary variable that could not always contain transport header
offset.

This is not a problem for TCP/UDP because port offset (@poff)
is 0 for these protocols.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-30 15:32:05 -04:00
Eric Dumazet 50d1784ee4 net: fix multiqueue selection
commit 416186fbf8 ("net: Split core bits of netdev_pick_tx
into __netdev_pick_tx") added a bug that disables caching of queue
index in the socket.

This is the source of packet reorders for TCP flows, and
again this is happening more often when using FQ pacing.

Old code was doing

if (queue_index != old_index)
	sk_tx_queue_set(sk, queue_index);

Alexander renamed the variables but forgot to change sk_tx_queue_set()
2nd parameter.

if (queue_index != new_index)
	sk_tx_queue_set(sk, queue_index);

This means we store -1 over and over in sk->sk_tx_queue_mapping

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-11 16:10:00 -04:00
David S. Miller 06c54055be Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
	net/bridge/br_multicast.c
	net/ipv6/sit.c

The conflicts were minor:

1) sit.c changes overlap with change to ip_tunnel_xmit() signature.

2) br_multicast.c had an overlap between computing max_delay using
   msecs_to_jiffies and turning MLDV2_MRC() into an inline function
   with a name using lowercase instead of uppercase letters.

3) stmmac had two overlapping changes, one which conditionally allocated
   and hooked up a dma_cfg based upon the presence of the pbl OF property,
   and another one handling store-and-forward DMA made.  The latter of
   which should not go into the new of_find_property() basic block.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-05 14:58:52 -04:00
Eric Dumazet 702821f4ea net: revert 8728c544a9 ("net: dev_pick_tx() fix")
commit 8728c544a9 ("net: dev_pick_tx() fix") and commit
b6fe83e952 ("bonding: refine IFF_XMIT_DST_RELEASE capability")
are quite incompatible : Queue selection is disabled because skb
dst was dropped before entering bonding device.

This causes major performance regression, mainly because TCP packets
for a given flow can be sent to multiple queues.

This is particularly visible when using the new FQ packet scheduler
with MQ + FQ setup on the slaves.

We can safely revert the first commit now that 416186fbf8
("net: Split core bits of netdev_pick_tx into __netdev_pick_tx")
properly caps the queue_index.

Reported-by: Xi Wang <xii@google.com>
Diagnosed-by: Xi Wang <xii@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Denys Fedorysychenko <nuclearcat@nuclearcat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-30 17:48:04 -04:00
David S. Miller 2ff1cf12c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-08-16 15:37:26 -07:00
Eric Dumazet e11aada32b net: flow_dissector: add 802.1ad support
Same behavior than 802.1q : finds the encapsulated protocol and
skip 32bit header.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09 11:06:23 -07:00
Tom Herbert b438f940d3 flow_dissector: add support for IPPROTO_IPV6
Support IPPROTO_IPV6 similar to IPPROTO_IPIP

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-30 19:16:52 -07:00
Tom Herbert fca4189551 flow_dissector: clean up IPIP case
Explicitly set proto to ETH_P_IP and jump directly to ip processing.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-30 19:16:51 -07:00
Daniel Borkmann f77668dc25 net: flow_dissector: add __skb_get_poff to get a start offset to payload
__skb_get_poff() returns the offset to the payload as far as it could
be dissected. The main user is currently BPF, so that we can dynamically
truncate packets without needing to push actual payload to the user
space and instead can analyze headers only.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20 13:15:45 -04:00
David S. Miller 61816596d1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull in the 'net' tree to get Daniel Borkmann's flow dissector
infrastructure change.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20 12:46:26 -04:00
Daniel Borkmann 8ed781668d flow_keys: include thoff into flow_keys for later usage
In skb_flow_dissect(), we perform a dissection of a skbuff. Since we're
doing the work here anyway, also store thoff for a later usage, e.g. in
the BPF filter.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-20 12:14:36 -04:00
Michael Dalton e1733de224 flow_dissector: support L2 GRE
Add support for L2 GRE tunnels, so that RPS can be more effective.

Signed-off-by: Michael Dalton <mwdalton@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-12 05:14:06 -04:00
Cong Wang 441d9d327f net: move rx and tx hash functions to net/core/flow_dissector.c
__skb_tx_hash() and __skb_get_rxhash() are all for calculating hash
value based by some fields in skb, mostly used for selecting queues
by device drivers.

Meanwhile, net/core/dev.c is bloating.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-21 14:26:17 -05:00
Eric Dumazet ddbe503203 ipv6: add ipv6_addr_hash() helper
Introduce ipv6_addr_hash() helper doing a XOR on all bits
of an IPv6 address, with an optimized x86_64 version.

Use it in flow dissector, as suggested by Andrew McGregor,
to reduce hash collision probabilities in fq_codel (and other
users of flow dissector)

Use it in ip6_tunnel.c and use more bit shuffling, as suggested
by David Laight, as existing hash was ignoring most of them.

Use it in sunrpc and use more bit shuffling, using hash_32().

Use it in net/ipv6/addrconf.c, using hash_32() as well.

As a cleanup, use it in net/ipv4/tcp_metrics.c

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrew McGregor <andrewmcgr@gmail.com>
Cc: Dave Taht <dave.taht@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-18 11:28:46 -07:00
Jesper Dangaard Brouer c452ed7077 net: flow_dissector.c missing include linux/export.h
The file net/core/flow_dissector.c seems to be missing
including linux/export.h.

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-24 16:03:33 -05:00
Eric Dumazet 4d77d2b567 flow_dissector: use a 64bit load/store
Le lundi 28 novembre 2011 à 19:06 -0500, David Miller a écrit :
> From: Dimitris Michailidis <dm@chelsio.com>
> Date: Mon, 28 Nov 2011 08:25:39 -0800
>
> >> +bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys
> >> *flow)
> >> +{
> >> +	int poff, nhoff = skb_network_offset(skb);
> >> +	u8 ip_proto;
> >> +	u16 proto = skb->protocol;
> >
> > __be16 instead of u16 for proto?
>
> I'll take care of this when I apply these patches.

( CC trimmed )

Thanks David !

Here is a small patch to use one 64bit load/store on x86_64 instead of
two 32bit load/stores.

[PATCH net-next] flow_dissector: use a 64bit load/store

gcc compiler is smart enough to use a single load/store if we
memcpy(dptr, sptr, 8) on x86_64, regardless of
CONFIG_CC_OPTIMIZE_FOR_SIZE

In IP header, daddr immediately follows saddr, this wont change in the
future. We only need to make sure our flow_keys (src,dst) fields wont
break the rule.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-29 13:17:03 -05:00
Eric Dumazet 0744dd00c1 net: introduce skb_flow_dissect()
We use at least two flow dissectors in network stack, with known
limitations and code duplication.

Introduce skb_flow_dissect() to factorize this, highly inspired from
existing dissector from __skb_get_rxhash()

Note : We extensively use skb_header_pointer(), this permits us to not
touch skb at all.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-28 19:09:07 -05:00