Commit Graph

43256 Commits

Author SHA1 Message Date
Eric Dumazet
bf8d85d4f9 ip_tunnel: do not clear l4 hashes
If skb has a valid l4 hash, there is no point clearing hash and force
a further flow dissection when a tunnel encapsulation is added.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 19:33:11 -07:00
David S. Miller
fa5f4aaf6e RxRPC rewrite
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIVAwUAV9FCuvSw1s6N8H32AQKo5w/8CySGsorFk67/QiQGdBt+URd8cxR2NuvF
 i3P7Kbo30ycJO7Q4Uc4DvO3kTqWiNMbXWVgGLfA64HDFojjuuXfQdFwf98FZ2WtQ
 OxQUV5fzSPFwlDktd5nWm5qTCdv7+lIvBCVsEPuX2pSkc7HesiYMsZt2ilOac9Ho
 Meon2/S1oq3hctZv2DTiaI+Ae8YBMar7GSUfylRGa2TkXCgG8eYcjGyGigLJ2F03
 e+/8w6+jtrW5hASCJPI9re+qiYgmnYa7UVpwrVjM1dVOYYZfmU02Jq6HgW9bSd24
 MYk6neksMGVpQbVmAbj5/MmxUg98q8UpY9ygt2IWP4UvGNDYBGCiSbfyQoTnoWUP
 02k3E6HnFfs8SPbxuNmA4uB2BHL2y87+G8u1g0IUZkT8i3zFwLd01UBwJqB23tYE
 EIRAad1xWwGaSJGyFgsmry1RJsitSUAG9w/68Ni1IMQxsHsIROTz6TNBki1tMcOh
 AAsbj4iJ0rJ2Ca/Xbk9kAdPzEr85ZA3Za5BwA9ZDwZjmt2X1RrzuK9gIaKB8hsWS
 zVjRjpvSOaTyx97rtEVfkT310GMGYC5r9ba+kE4ukGeHWKRVkMk5tkADZw9RFKdf
 ubXN/zyfv4YABHHUIfQn5UgHHmxl4GpN0CD+cY7hPtmB9J2wvsadckqrzBOFIQL+
 dg7jZAb+fjc=
 =GfEj
 -----END PGP SIGNATURE-----

Merge tag 'rxrpc-rewrite-20160908' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Rewrite data and ack handling

This patch set constitutes the main portion of the AF_RXRPC rewrite.  It
consists of five fix/helper patches:

 (1) Fix ASSERTCMP's and ASSERTIFCMP's handling of signed values.

 (2) Update some protocol definitions slightly.

 (3) Use of an hlist for RCU purposes.

 (4) Removal of per-call sk_buff accounting (not really needed when skbs
     aren't being queued on the main queue).

 (5) Addition of a tracepoint to log incoming packets in the data_ready
     callback and to log the end of the data_ready callback.

And then there are two patches that form the main part:

 (6) Preallocation of resources for incoming calls so that in patch (7) the
     data_ready handler can be made to fully instantiate an incoming call
     and make it live.  This extends through into AFS so that AFS can
     preallocate its own incoming call resources.

     The preallocation size is capped at the listen() backlog setting - and
     that is capped at a sysctl limit which can be set between 4 and 32.

     The preallocation is (re)charged either by accepting/rejecting pending
     calls or, in the case of AFS, manually.  If insufficient preallocation
     resources exist, a BUSY packet will be transmitted.

     The advantage of using this preallocation is that once a call is set
     up in the data_ready handler, DATA packets can be queued on it
     immediately rather than the DATA packets being queued for a background
     work item to do all the allocation and then try and sort out the DATA
     packets whilst other DATA packets may still be coming in and going
     either to the background thread or the new call.

 (7) Rewrite the handling of DATA, ACK and ABORT packets.

     In the receive phase, DATA packets are now held in per-call circular
     buffers with deduplication, out of sequence detection and suchlike
     being done in data_ready.  Since there is only one producer and only
     once consumer, no locks need be used on the receive queue.

     Received ACK and ABORT packets are now parsed and discarded in
     data_ready to recycle resources as fast as possible.

     sk_buffs are no longer pulled, trimmed or cloned, but rather the
     offset and size of the content is tracked.  This particularly affects
     jumbo DATA packets which need insertion into the receive buffer in
     multiple places.  Annotations are kept to track which bit is which.

     Packets are no longer queued on the socket receive queue; rather,
     calls are queued.  Dummy packets to convey events therefore no longer
     need to be invented and metadata packets can be discarded as soon as
     parsed rather then being pushed onto the socket receive queue to
     indicate terminal events.

     The preallocation facility added in (6) is now used to set up incoming
     calls with very little locking required and no calls to the allocator
     in data_ready.

     Decryption and verification is now handled in recvmsg() rather than in
     a background thread.  This allows for the future possibility of
     decrypting directly into the user buffer.

     With this patch, the code is a lot simpler and most of the mass of
     call event and state wangling code in call_event.c is gone.

With this, the majority of the AF_RXRPC rewrite is complete.  However,
there are still things to be done, including:

 (*) Limit the number of active service calls to prevent an attacker from
     filling up a server's memory.

 (*) Limit the number of calls on the rebuff-with-BUSY queue.

 (*) Transmit delayed/deferred ACKs from recvmsg() if possible, rather than
     punting to the background thread.  Ideally, the background thread
     shouldn't run at all, but data_ready can't call kernel_sendmsg() and
     we can't rely on recvmsg() attending to the call in a timely fashion.

 (*) Prevent the call at the front of the socket queue from hogging
     recvmsg()'s attention if there's a sufficiently continuous supply of
     data.

 (*) Distribute ICMP errors by connection rather than by call.  Possibly
     parse the ICMP packet to try and pin down the exact connection and
     call.

 (*) Encrypt/decrypt directly between user buffers and socket buffers where
     possible.

 (*) IPv6.

 (*) Service ID upgrade.  This is a facility whereby a special flag bit is
     set in the DATA packet header when making a call that tells the server
     that it is allowed to change the service ID to an upgraded one and
     reply with an equivalent call from the upgraded service.

     This is used, for example, to override certain AFS calls so that IPv6
     addresses can be returned.

 (*) Allow userspace to preallocate call user IDs for incoming calls.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 19:24:21 -07:00
Colin Ian King
05f1b12f71 net: x25: remove null checks on arrays calling_ae and called_ae
dtefacs.calling_ae and called_ae are both 20 element __u8 arrays and
cannot be null and hence are redundant checks. Remove these.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 18:13:30 -07:00
stephen hemminger
b8b867e132 rtnetlink: remove unused ifla_stats_policy
This structure is defined but never used. Flagged with W=1

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 16:52:43 -07:00
Guillaume Nault
73483c1289 ipv6: report NLM_F_CREATE and NLM_F_EXCL flags in RTM_NEWROUTE events
Since commit 37a1d3611c ("ipv6: include NLM_F_REPLACE in route
replace notifications"), RTM_NEWROUTE notifications have their
NLM_F_REPLACE flag set if the new route replaced a preexisting one.
However, other flags aren't set.

This patch reports the missing NLM_F_CREATE and NLM_F_EXCL flag bits.

NLM_F_APPEND is not reported, because in ipv6 a NLM_F_CREATE request
is interpreted as an append request (contrary to ipv4, "prepend" is not
supported, so if NLM_F_EXCL is not set then NLM_F_APPEND is implicit).

As a result, the possible flag combination can now be reported
(iproute2's terminology into parentheses):

  * NLM_F_CREATE | NLM_F_EXCL: route didn't exist, exclusive creation
    ("add").
  * NLM_F_CREATE: route did already exist, new route added after
    preexisting ones ("append").
  * NLM_F_REPLACE: route did already exist, new route replaced the
    first preexisting one ("change").

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 16:50:23 -07:00
Guillaume Nault
b93e1fa710 ipv4: fix value of ->nlmsg_flags reported in RTM_NEWROUTE events
fib_table_insert() inconsistently fills the nlmsg_flags field in its
notification messages.

Since commit b8f5583135 ("[RTNETLINK]: Fix sending netlink message
when replace route."), the netlink message has its nlmsg_flags set to
NLM_F_REPLACE if the route replaced a preexisting one.

Then commit a2bb6d7d6f ("ipv4: include NLM_F_APPEND flag in append
route notifications") started setting nlmsg_flags to NLM_F_APPEND if
the route matched a preexisting one but was appended.

In other cases (exclusive creation or prepend), nlmsg_flags is 0.

This patch sets ->nlmsg_flags in all situations, preserving the
semantic of the NLM_F_* bits:

  * NLM_F_CREATE: a new fib entry has been created for this route.
  * NLM_F_EXCL: no other fib entry existed for this route.
  * NLM_F_REPLACE: this route has overwritten a preexisting fib entry.
  * NLM_F_APPEND: the new fib entry was added after other entries for
    the same route.

As a result, the possible flag combination can now be reported
(iproute2's terminology into parentheses):

  * NLM_F_CREATE | NLM_F_EXCL: route didn't exist, exclusive creation
    ("add").
  * NLM_F_CREATE | NLM_F_APPEND: route did already exist, new route
    added after preexisting ones ("append").
  * NLM_F_CREATE: route did already exist, new route added before
    preexisting ones ("prepend").
  * NLM_F_REPLACE: route did already exist, new route replaced the
    first preexisting one ("change").

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-09 16:50:23 -07:00
Eric Dumazet
e895cdce68 ipv4: accept u8 in IP_TOS ancillary data
In commit f02db315b8 ("ipv4: IP_TOS and IP_TTL can be specified as
ancillary data") Francesco added IP_TOS values specified as integer.

However, kernel sends to userspace (at recvmsg() time) an IP_TOS value
in a single byte, when IP_RECVTOS is set on the socket.

It can be very useful to reflect all ancillary options as given by the
kernel in a subsequent sendmsg(), instead of aborting the sendmsg() with
EINVAL after Francesco patch.

So this patch extends IP_TOS ancillary to accept an u8, so that an UDP
server can simply reuse same ancillary block without having to mangle
it.

Jesper can then augment
https://github.com/netoptimizer/network-testing/blob/master/src/udp_example02.c
to add TOS reflection ;)

Fixes: f02db315b8 ("ipv4: IP_TOS and IP_TTL can be specified as ancillary data")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Francesco Fusco <ffusco@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 17:45:57 -07:00
Yaogong Wang
9f5afeae51 tcp: use an RB tree for ooo receive queue
Over the years, TCP BDP has increased by several orders of magnitude,
and some people are considering to reach the 2 Gbytes limit.

Even with current window scale limit of 14, ~1 Gbytes maps to ~740,000
MSS.

In presence of packet losses (or reorders), TCP stores incoming packets
into an out of order queue, and number of skbs sitting there waiting for
the missing packets to be received can be in the 10^5 range.

Most packets are appended to the tail of this queue, and when
packets can finally be transferred to receive queue, we scan the queue
from its head.

However, in presence of heavy losses, we might have to find an arbitrary
point in this queue, involving a linear scan for every incoming packet,
throwing away cpu caches.

This patch converts it to a RB tree, to get bounded latencies.

Yaogong wrote a preliminary patch about 2 years ago.
Eric did the rebase, added ofo_last_skb cache, polishing and tests.

Tested with network dropping between 1 and 10 % packets, with good
success (about 30 % increase of throughput in stress tests)

Next step would be to also use an RB tree for the write queue at sender
side ;)

Signed-off-by: Yaogong Wang <wygivan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-By: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 17:25:58 -07:00
Eric Garver
018c1dda5f openvswitch: 802.1AD Flow handling, actions, vlan parsing, netlink attributes
Add support for 802.1ad including the ability to push and pop double
tagged vlans. Add support for 802.1ad to netlink parsing and flow
conversion. Uses double nested encap attributes to represent double
tagged vlan. Inner TPID encoded along with ctci in nested attributes.

This is based on Thomas F Herbert's original v20 patch. I made some
small clean ups and bug fixes.

Signed-off-by: Thomas F Herbert <thomasfherbert@gmail.com>
Signed-off-by: Eric Garver <e@erig.me>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 17:10:28 -07:00
Lorenzo Colitti
d545caca82 net: inet: diag: expose the socket mark to privileged processes.
This adds the capability for a process that has CAP_NET_ADMIN on
a socket to see the socket mark in socket dumps.

Commit a52e95abf7 ("net: diag: allow socket bytecode filters to
match socket marks") recently gave privileged processes the
ability to filter socket dumps based on mark. This patch is
complementary: it ensures that the mark is also passed to
userspace in the socket's netlink attributes.  It is useful for
tools like ss which display information about sockets.

Tested: https://android-review.googlesource.com/270210
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 16:13:09 -07:00
David S. Miller
575f9c43e7 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
ipsec-next 2016-09-08

1) Constify the xfrm_replay structures. From Julia Lawall

2) Protect xfrm state hash tables with rcu, lookups
   can be done now without acquiring xfrm_state_lock.
   From Florian Westphal.

3) Protect xfrm policy hash tables with rcu, lookups
   can be done now without acquiring xfrm_policy_lock.
   From Florian Westphal.

4) We don't need to have a garbage collector list per
   namespace anymore, so use a global one instead.
   From Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-08 13:09:41 -07:00
David Howells
248f219cb8 rxrpc: Rewrite the data and ack handling code
Rewrite the data and ack handling code such that:

 (1) Parsing of received ACK and ABORT packets and the distribution and the
     filing of DATA packets happens entirely within the data_ready context
     called from the UDP socket.  This allows us to process and discard ACK
     and ABORT packets much more quickly (they're no longer stashed on a
     queue for a background thread to process).

 (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim().  We instead
     keep track of the offset and length of the content of each packet in
     the sk_buff metadata.  This means we don't do any allocation in the
     receive path.

 (3) Jumbo DATA packet parsing is now done in data_ready context.  Rather
     than cloning the packet once for each subpacket and pulling/trimming
     it, we file the packet multiple times with an annotation for each
     indicating which subpacket is there.  From that we can directly
     calculate the offset and length.

 (4) A call's receive queue can be accessed without taking locks (memory
     barriers do have to be used, though).

 (5) Incoming calls are set up from preallocated resources and immediately
     made live.  They can than have packets queued upon them and ACKs
     generated.  If insufficient resources exist, DATA packet #1 is given a
     BUSY reply and other DATA packets are discarded).

 (6) sk_buffs no longer take a ref on their parent call.

To make this work, the following changes are made:

 (1) Each call's receive buffer is now a circular buffer of sk_buff
     pointers (rxtx_buffer) rather than a number of sk_buff_heads spread
     between the call and the socket.  This permits each sk_buff to be in
     the buffer multiple times.  The receive buffer is reused for the
     transmit buffer.

 (2) A circular buffer of annotations (rxtx_annotations) is kept parallel
     to the data buffer.  Transmission phase annotations indicate whether a
     buffered packet has been ACK'd or not and whether it needs
     retransmission.

     Receive phase annotations indicate whether a slot holds a whole packet
     or a jumbo subpacket and, if the latter, which subpacket.  They also
     note whether the packet has been decrypted in place.

 (3) DATA packet window tracking is much simplified.  Each phase has just
     two numbers representing the window (rx_hard_ack/rx_top and
     tx_hard_ack/tx_top).

     The hard_ack number is the sequence number before base of the window,
     representing the last packet the other side says it has consumed.
     hard_ack starts from 0 and the first packet is sequence number 1.

     The top number is the sequence number of the highest-numbered packet
     residing in the buffer.  Packets between hard_ack+1 and top are
     soft-ACK'd to indicate they've been received, but not yet consumed.

     Four macros, before(), before_eq(), after() and after_eq() are added
     to compare sequence numbers within the window.  This allows for the
     top of the window to wrap when the hard-ack sequence number gets close
     to the limit.

     Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also
     to indicate when rx_top and tx_top point at the packets with the
     LAST_PACKET bit set, indicating the end of the phase.

 (4) Calls are queued on the socket 'receive queue' rather than packets.
     This means that we don't need have to invent dummy packets to queue to
     indicate abnormal/terminal states and we don't have to keep metadata
     packets (such as ABORTs) around

 (5) The offset and length of a (sub)packet's content are now passed to
     the verify_packet security op.  This is currently expected to decrypt
     the packet in place and validate it.

     However, there's now nowhere to store the revised offset and length of
     the actual data within the decrypted blob (there may be a header and
     padding to skip) because an sk_buff may represent multiple packets, so
     a locate_data security op is added to retrieve these details from the
     sk_buff content when needed.

 (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is
     individually secured and needs to be individually decrypted.  The code
     to do this is broken out into rxrpc_recvmsg_data() and shared with the
     kernel API.  It now iterates over the call's receive buffer rather
     than walking the socket receive queue.

Additional changes:

 (1) The timers are condensed to a single timer that is set for the soonest
     of three timeouts (delayed ACK generation, DATA retransmission and
     call lifespan).

 (2) Transmission of ACK and ABORT packets is effected immediately from
     process-context socket ops/kernel API calls that cause them instead of
     them being punted off to a background work item.  The data_ready
     handler still has to defer to the background, though.

 (3) A shutdown op is added to the AF_RXRPC socket so that the AFS
     filesystem can shut down the socket and flush its own work items
     before closing the socket to deal with any in-progress service calls.

Future additional changes that will need to be considered:

 (1) Make sure that a call doesn't hog the front of the queue by receiving
     data from the network as fast as userspace is consuming it to the
     exclusion of other calls.

 (2) Transmit delayed ACKs from within recvmsg() when we've consumed
     sufficiently more packets to avoid the background work item needing to
     run.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:12 +01:00
David Howells
00e907127e rxrpc: Preallocate peers, conns and calls for incoming service requests
Make it possible for the data_ready handler called from the UDP transport
socket to completely instantiate an rxrpc_call structure and make it
immediately live by preallocating all the memory it might need.  The idea
is to cut out the background thread usage as much as possible.

[Note that the preallocated structs are not actually used in this patch -
 that will be done in a future patch.]

If insufficient resources are available in the preallocation buffers, it
will be possible to discard the DATA packet in the data_ready handler or
schedule a BUSY packet without the need to schedule an attempt at
allocation in a background thread.

To this end:

 (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a
     maximum number each of the listen backlog size.  The backlog size is
     limited to a maxmimum of 32.  Only this many of each can be in the
     preallocation buffer.

 (2) For userspace sockets, the preallocation is charged initially by
     listen() and will be recharged by accepting or rejecting pending
     new incoming calls.

 (3) For kernel services {,re,dis}charging of the preallocation buffers is
     handled manually.  Two notifier callbacks have to be provided before
     kernel_listen() is invoked:

     (a) An indication that a new call has been instantiated.  This can be
     	 used to trigger background recharging.

     (b) An indication that a call is being discarded.  This is used when
     	 the socket is being released.

     A function, rxrpc_kernel_charge_accept() is called by the kernel
     service to preallocate a single call.  It should be passed the user ID
     to be used for that call and a callback to associate the rxrpc call
     with the kernel service's side of the ID.

 (4) Discard the preallocation when the socket is closed.

 (5) Temporarily bump the refcount on the call allocated in
     rxrpc_incoming_call() so that rxrpc_release_call() can ditch the
     preallocation ref on service calls unconditionally.  This will no
     longer be necessary once the preallocation is used.

Note that this does not yet control the number of active service calls on a
client - that will come in a later patch.

A future development would be to provide a setsockopt() call that allows a
userspace server to manually charge the preallocation buffer.  This would
allow user call IDs to be provided in advance and the awkward manual accept
stage to be bypassed.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:12 +01:00
David Howells
49e19ec7d3 rxrpc: Add tracepoints to record received packets and end of data_ready
Add two tracepoints:

 (1) Record the RxRPC protocol header of packets retrieved from the UDP
     socket by the data_ready handler.

 (2) Record the outcome of the data_ready handler.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:12 +01:00
David Howells
2ab27215ea rxrpc: Remove skb_count from struct rxrpc_call
Remove the sk_buff count from the rxrpc_call struct as it's less useful
once we stop queueing sk_buffs.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:12 +01:00
David Howells
de8d6c7401 rxrpc: Convert rxrpc_local::services to an hlist
Convert the rxrpc_local::services list to an hlist so that it can be
accessed under RCU conditions more readily.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:11 +01:00
David Howells
cf13258fd4 rxrpc: Fix ASSERTCMP and ASSERTIFCMP to handle signed values
Fix ASSERTCMP and ASSERTIFCMP to be able to handle signed values by casting
both parameters to the type of the first before comparing.  Without this,
both values are cast to unsigned long, which means that checks for values
less than zero don't work.

The downside of this is that the state enum values in struct rxrpc_call and
struct rxrpc_connection can't be bitfields as __typeof__ can't handle them.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:11 +01:00
subashab@codeaurora.org
0f76d25644 net: xfrm: Change u32 sysctl entries to use proc_douintvec
proc_dointvec limits the values to INT_MAX in u32 sysctl entries.
proc_douintvec allows to write upto UINT_MAX.

Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-07 23:17:53 -07:00
Lorenzo Colitti
f95bf34622 net: diag: make udp_diag_destroy work for mapped addresses.
udp_diag_destroy does look up the IPv4 UDP hashtable for mapped
addresses, but it gets the IPv4 address to look up from the
beginning of the IPv6 address instead of the end.

Tested: https://android-review.googlesource.com/269874
Fixes: 5d77dca828 ("net: diag: support SOCK_DESTROY for UDP sockets")
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-07 17:31:30 -07:00
Andrey Vagin
733ade23de netlink: don't forget to release a rhashtable_iter structure
This bug was detected by kmemleak:
unreferenced object 0xffff8804269cc3c0 (size 64):
  comm "criu", pid 1042, jiffies 4294907360 (age 13.713s)
  hex dump (first 32 bytes):
    a0 32 cc 2c 04 88 ff ff 00 00 00 00 00 00 00 00  .2.,............
    00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de  ................
  backtrace:
    [<ffffffff8184dffa>] kmemleak_alloc+0x4a/0xa0
    [<ffffffff8124720f>] kmem_cache_alloc_trace+0x10f/0x280
    [<ffffffffa02864cc>] __netlink_diag_dump+0x26c/0x290 [netlink_diag]

v2: don't remove a reference on a rhashtable_iter structure to
    release it from netlink_diag_dump_done

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Fixes: ad20207432 ("netlink: Use rhashtable walk interface in diag dump")
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-07 17:29:38 -07:00
David Howells
5a42976d4f rxrpc: Add tracepoint for working out where aborts happen
Add a tracepoint for working out where local aborts happen.  Each
tracepoint call is labelled with a 3-letter code so that they can be
distinguished - and the DATA sequence number is added too where available.

rxrpc_kernel_abort_call() also takes a 3-letter code so that AFS can
indicate the circumstances when it aborts a call.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 16:34:40 +01:00
David Howells
e8d6bbb05a rxrpc: Fix returns of call completion helpers
rxrpc_set_call_completion() returns bool, not int, so the ret variable
should match this.

rxrpc_call_completed() and __rxrpc_call_completed() should return the value
of rxrpc_set_call_completion().

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 16:34:30 +01:00
David Howells
8d94aa381d rxrpc: Calls shouldn't hold socket refs
rxrpc calls shouldn't hold refs on the sock struct.  This was done so that
the socket wouldn't go away whilst the call was in progress, such that the
call could reach the socket's queues.

However, we can mark the socket as requiring an RCU release and rely on the
RCU read lock.

To make this work, we do:

 (1) rxrpc_release_call() removes the call's call user ID.  This is now
     only called from socket operations and not from the call processor:

	rxrpc_accept_call() / rxrpc_kernel_accept_call()
	rxrpc_reject_call() / rxrpc_kernel_reject_call()
	rxrpc_kernel_end_call()
	rxrpc_release_calls_on_socket()
	rxrpc_recvmsg()

     Though it is also called in the cleanup path of
     rxrpc_accept_incoming_call() before we assign a user ID.

 (2) Pass the socket pointer into rxrpc_release_call() rather than getting
     it from the call so that we can get rid of uninitialised calls.

 (3) Fix call processor queueing to pass a ref to the work queue and to
     release that ref at the end of the processor function (or to pass it
     back to the work queue if we have to requeue).

 (4) Skip out of the call processor function asap if the call is complete
     and don't requeue it if the call is complete.

 (5) Clean up the call immediately that the refcount reaches 0 rather than
     trying to defer it.  Actual deallocation is deferred to RCU, however.

 (6) Don't hold socket refs for allocated calls.

 (7) Use the RCU read lock when queueing a message on a socket and treat
     the call's socket pointer according to RCU rules and check it for
     NULL.

     We also need to use the RCU read lock when viewing a call through
     procfs.

 (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call()
     if this hasn't been done yet so that we can then disconnect the call.
     Once the call is disconnected, it won't have any access to the
     connection struct and the UDP socket for the call work processor to be
     able to send the ACK.  Terminal retransmission will be handled by the
     connection processor.

 (9) Release all calls immediately on the closing of a socket rather than
     trying to defer this.  Incomplete calls will be aborted.

The call refcount model is much simplified.  Refs are held on the call by:

 (1) A socket's user ID tree.

 (2) A socket's incoming call secureq and acceptq.

 (3) A kernel service that has a call in progress.

 (4) A queued call work processor.  We have to take care to put any call
     that we failed to queue.

 (5) sk_buffs on a socket's receive queue.  A future patch will get rid of
     this.

Whilst we're at it, we can do:

 (1) Get rid of the RXRPC_CALL_EV_RELEASE event.  Release is now done
     entirely from the socket routines and never from the call's processor.

 (2) Get rid of the RXRPC_CALL_DEAD state.  Calls now end in the
     RXRPC_CALL_COMPLETE state.

 (3) Get rid of the rxrpc_call::destroyer work item.  Calls are now torn
     down when their refcount reaches 0 and then handed over to RCU for
     final cleanup.

 (4) Get rid of the rxrpc_call::deadspan timer.  Calls are cleaned up
     immediately they're finished with and don't hang around.
     Post-completion retransmission is handled by the connection processor
     once the call is disconnected.

 (5) Get rid of the dead call expiry setting as there's no longer a timer
     to set.

 (6) rxrpc_destroy_all_calls() can just check that the call list is empty.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:33:20 +01:00
David Howells
6543ac5235 rxrpc: Use rxrpc_is_service_call() rather than rxrpc_conn_is_service()
Use rxrpc_is_service_call() rather than rxrpc_conn_is_service() if the call
is available just in case call->conn is NULL.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:30:22 +01:00
David Howells
8b7fac50ab rxrpc: Pass the connection pointer to rxrpc_post_packet_to_call()
Pass the connection pointer to rxrpc_post_packet_to_call() as the call
might get disconnected whilst we're looking at it, but the connection
pointer determined by rxrpc_data_read() is guaranteed by RCU for the
duration of the call.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:30:22 +01:00
David Howells
278ac0cdd5 rxrpc: Cache the security index in the rxrpc_call struct
Cache the security index in the rxrpc_call struct so that we can get at it
even when the call has been disconnected and the connection pointer
cleared.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:30:22 +01:00
David Howells
f4fdb3525b rxrpc: Use call->peer rather than call->conn->params.peer
Use call->peer rather than call->conn->params.peer to avoid the possibility
of call->conn being NULL and, whilst we're at it, check it for NULL before we
access it.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:30:22 +01:00
David Howells
fff72429c2 rxrpc: Improve the call tracking tracepoint
Improve the call tracking tracepoint by showing more differentiation
between some of the put and get events, including:

  (1) Getting and putting refs for the socket call user ID tree.

  (2) Getting and putting refs for queueing and failing to queue the call
      processor work item.

Note that these aren't necessarily used in this patch, but will be taken
advantage of in future patches.

An enum is added for the event subtype numbers rather than coding them
directly as decimal numbers and a table of 3-letter strings is provided
rather than a sequence of ?: operators.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 15:30:22 +01:00
David Howells
e796cb4192 rxrpc: Delete unused rxrpc_kernel_free_skb()
Delete rxrpc_kernel_free_skb() as it's unused.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 14:43:43 +01:00
David Howells
71a17de307 rxrpc: Whitespace cleanup
Remove some whitespace.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 14:43:39 +01:00
David S. Miller
c7ee5672f3 RxRPC rewrite
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIVAwUAV8yHP/Sw1s6N8H32AQL7cQ//S3MP4x690tV49UocezdAV8PuV3HpM5kt
 a+43v8RqjTHaZQxOwQaG71OpAM2gH1z7QPSq6jsLy0PEmaPiP/MZOAWqUudBAyqo
 eVsEMEVlw0f7PogyKqr06uPoVo21IdLNX9E89CqaGqFuDfsKlj1bKQHH4/248Arr
 i4ztzid/Mj98fHvzqMdr631c06GvLozU/5X6xE7hzkGkqVmRtjIB6qETGqerwx/p
 GJlcTZVFw2EviS6/Ft/t26xgVsOg1ogzXjWLUufnnJ1GpRaucqMfHwYD0WqQV3sB
 Bu6WRx2JgXRPBi5m7gWymkgT0pUNRiDFuWN6qdlJbHJgKGuVojF6tnh2go2bj9Cq
 q/GLbi8Y810v64293i1vdz6yyM1PzDG648+6z8vbTpsLI7cHDq5csPYMHRIh34IM
 FQmSZblKIuALD8BXqW1lXrqVKU0WEFVI9WjcRk9OSIanqPrQyP8xOAJVp03uIGe/
 uxkheJBy7XvghwKWZNZ1y0A0g6NxY0gNMhVsmW77VbNfOsKOpEcpSCvMwjgMOvDi
 npynisM8tf2cx973SZYXjvvl2LSMHjiVQ/tf0iTMYmBjtU7ft5i8p3w290yAD+JQ
 JKqpKq3TXVty5MMEXl5bStIr/HkgPk7e6v1sH9WIREu9m9gROANGe/9Mr4VvweHk
 jEuFHy2EZNE=
 =3Don
 -----END PGP SIGNATURE-----

Merge tag 'rxrpc-rewrite-20160904-2' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Split output code from sendmsg code

Here's a set of small patches that split the packet transmission code from
the sendmsg code and simply rearrange the new file to make it more
logically laid out ready for being rewritten.  An enum is also moved out of
the header file to there as it's only used there.  This needs to be applied
on top of the just-posted fixes patch set.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 13:53:29 -07:00
David S. Miller
0122c6d5fa RxRPC rewrite
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIVAwUAV8yHKPSw1s6N8H32AQKbWA/+MEjzVzIOpp4edvAj5DzdO5pls3NvhUAg
 2sP15E9nOL9JHrOD5snCVSRd9ROEGRE0/S9WXUjeb2VKz7C2pmTixo+MjiJRMzAR
 TZZlE2Ydx0h+A7WiywKoTY4g7VICL+UC+4XcheMzTLNS2mzqKb2GGOm3BwvGaFeT
 RKRVIlwIHziShaIs7K7ZkfKxGaDIL/9x344uPfFHaDKb33aOBnTuY6HlFf5Yu2qm
 pzh+R7cBYJMvhEqd71ESYPSbSGnjBN5zRzjZDSvXeI/30k9Ee6mFastv4fdG3Mrk
 0WOLxml9yLTlJnfXeuN0T9B0C/ur4oD4hKEDREXVTxcTEXRq/VxSJ3cYxeM3DlAz
 U795lcveiYajRv7F73jcfNuaEENQg5HsZuaFs+CJgVxQpsqs9IOpEl9CNrVsvjmf
 9crgamUj34ehZ5lgsV/Qbm7OFk16dmQ59ImGClQFgsIU6hEWCP0VgwKXWTwP7YZD
 Ucp1zWp/XTAtbrRNdkye/Z0WE5QOtoUWzftPrf95TP7LFewp0DGZ+miBV/atSHbZ
 bADXR0SOtax8u9bfs1HYTadwHk1LJYuVXNYn/KN06c9q1WKuKH/qg0JAjv/KUnJm
 Nnx0TFh4kUg999+3CtxqmupiqkD5SCckCN2ggifgDCmQhEwr1CYrGKWpZvNMq+S6
 nVNTUr7PYSI=
 =RRYk
 -----END PGP SIGNATURE-----

Merge tag 'rxrpc-rewrite-20160904-1' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Small fixes

Here's a set of small fix patches:

 (1) Fix some uninitialised variables.

 (2) Set the client call state before making it live by attaching it to the
     conn struct.

 (3) Randomise the epoch and starting client conn ID values, and don't
     change the epoch when the client conn ID rolls round.

 (4) Replace deprecated create_singlethread_workqueue() calls.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 13:46:26 -07:00
David S. Miller
60175ccdf4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree.  Most relevant updates are the removal of per-conntrack timers to
use a workqueue/garbage collection approach instead from Florian
Westphal, the hash and numgen expression for nf_tables from Laura
Garcia, updates on nf_tables hash set to honor the NLM_F_EXCL flag,
removal of ip_conntrack sysctl and many other incremental updates on our
Netfilter codebase.

More specifically, they are:

1) Retrieve only 4 bytes to fetch ports in case of non-linear skb
   transport area in dccp, sctp, tcp, udp and udplite protocol
   conntrackers, from Gao Feng.

2) Missing whitespace on error message in physdev match, from Hangbin Liu.

3) Skip redundant IPv4 checksum calculation in nf_dup_ipv4, from Liping Zhang.

4) Add nf_ct_expires() helper function and use it, from Florian Westphal.

5) Replace opencoded nf_ct_kill() call in IPVS conntrack support, also
   from Florian.

6) Rename nf_tables set implementation to nft_set_{name}.c

7) Introduce the hash expression to allow arbitrary hashing of selector
   concatenations, from Laura Garcia Liebana.

8) Remove ip_conntrack sysctl backward compatibility code, this code has
   been around for long time already, and we have two interfaces to do
   this already: nf_conntrack sysctl and ctnetlink.

9) Use nf_conntrack_get_ht() helper function whenever possible, instead
   of opencoding fetch of hashtable pointer and size, patch from Liping Zhang.

10) Add quota expression for nf_tables.

11) Add number generator expression for nf_tables, this supports
    incremental and random generators that can be combined with maps,
    very useful for load balancing purpose, again from Laura Garcia Liebana.

12) Fix a typo in a debug message in FTP conntrack helper, from Colin Ian King.

13) Introduce a nft_chain_parse_hook() helper function to parse chain hook
    configuration, this is used by a follow up patch to perform better chain
    update validation.

14) Add rhashtable_lookup_get_insert_key() to rhashtable and use it from the
    nft_set_hash implementation to honor the NLM_F_EXCL flag.

15) Missing nulls check in nf_conntrack from nf_conntrack_tuple_taken(),
    patch from Florian Westphal.

16) Don't use the DYING bit to know if the conntrack event has been already
    delivered, instead a state variable to track event re-delivery
    states, also from Florian.

17) Remove the per-conntrack timer, use the workqueue approach that was
    discussed during the NFWS, from Florian Westphal.

18) Use the netlink conntrack table dump path to kill stale entries,
    again from Florian.

19) Add a garbage collector to get rid of stale conntracks, from
    Florian.

20) Reschedule garbage collector if eviction rate is high.

21) Get rid of the __nf_ct_kill_acct() helper.

22) Use ARPHRD_ETHER instead of hardcoded 1 from ARP logger.

23) Make nf_log_set() interface assertive on unsupported families.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-06 12:45:26 -07:00
David Howells
3dc20f090d rxrpc Move enum rxrpc_command to sendmsg.c
Move enum rxrpc_command to sendmsg.c as it's now only used in that file.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 21:41:39 +01:00
David Howells
df423a4af1 rxrpc: Rearrange net/rxrpc/sendmsg.c
Rearrange net/rxrpc/sendmsg.c to be in a more logical order.  This makes it
easier to follow and eliminates forward declarations.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 21:41:39 +01:00
David Howells
0b58b8a18b rxrpc: Split sendmsg from packet transmission code
Split the sendmsg code from the packet transmission code (mostly to be
found in output.c).

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 21:41:39 +01:00
David Howells
090f85deb6 rxrpc: Don't change the epoch
It seems the local epoch should only be changed on boot, so remove the code
that changes it for client connections.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 21:41:39 +01:00
David Howells
5f2d9c4438 rxrpc: Randomise epoch and starting client conn ID values
Create a random epoch value rather than a time-based one on startup and set
the top bit to indicate that this is the case.

Also create a random starting client connection ID value.  This will be
incremented from here as new client connections are created.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 21:41:39 +01:00
WANG Cong
bc51dddf98 netns: avoid disabling irq for netns id
We never read or change netns id in hardirq context,
the only place we read netns id in softirq context
is in vxlan_xmit(). So, it should be enough to just
disable BH.

Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 11:39:59 -07:00
WANG Cong
38f507f1ba vxlan: call peernet2id() in fdb notification
netns id should be already allocated each time we change
netns, that is, in dev_change_net_namespace() (more precisely
in rtnl_fill_ifinfo()). It is safe to just call peernet2id() here.

Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 11:39:58 -07:00
Joe Stringer
76644232e6 openvswitch: Free tmpl with tmpl_free.
When an error occurs during conntrack template creation as part of
actions validation, we need to free the template. Previously we've been
using nf_ct_put() to do this, but nf_ct_tmpl_free() is more appropriate.

Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 11:38:10 -07:00
David Howells
af338a9ea6 rxrpc: The client call state must be changed before attachment to conn
We must set the client call state to RXRPC_CALL_CLIENT_SEND_REQUEST before
attaching the call to the connection struct, not after, as it's liable to
receive errors and conn aborts as soon as the assignment is made - and
these will cause its state to be changed outside of the initiating thread's
control.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 13:10:10 +01:00
Jon Paul Maloy
e0a05ebe26 tipc: send broadcast nack directly upon sequence gap detection
Because of the risk of an excessive number of NACK messages and
retransissions, receivers have until now abstained from sending
broadcast NACKS directly upon detection of a packet sequence number
gap. We have instead relied on such gaps being detected by link
protocol STATE message exchange, something that by necessity delays
such detection and subsequent retransmissions.

With the introduction of unicast NACK transmission and rate control
of retransmissions we can now remove this limitation. We now allow
receiving nodes to send NACKS immediately, while coordinating the
permission to do so among the nodes in order to avoid NACK storms.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02 17:10:25 -07:00
Jon Paul Maloy
7c4a54b963 tipc: rate limit broadcast retransmissions
As cluster sizes grow, so does the amount of identical or overlapping
broadcast NACKs generated by the packet receivers. This often leads to
'NACK crunches' resulting in huge numbers of redundant retransmissions
of the same packet ranges.

In this commit, we introduce rate control of broadcast retransmissions,
so that a retransmitted range cannot be retransmitted again until after
at least 10 ms. This reduces the frequency of duplicate, redundant
retransmissions by an order of magnitude, while having a significant
positive impact on overall throughput and scalability.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02 17:10:24 -07:00
Jon Paul Maloy
02d11ca200 tipc: transfer broadcast nacks in link state messages
When we send broadcasts in clusters of more 70-80 nodes, we sometimes
see the broadcast link resetting because of an excessive number of
retransmissions. This is caused by a combination of two factors:

1) A 'NACK crunch", where loss of broadcast packets is discovered
   and NACK'ed by several nodes simultaneously, leading to multiple
   redundant broadcast retransmissions.

2) The fact that the NACKS as such also are sent as broadcast, leading
   to excessive load and packet loss on the transmitting switch/bridge.

This commit deals with the latter problem, by moving sending of
broadcast nacks from the dedicated BCAST_PROTOCOL/NACK message type
to regular unicast LINK_PROTOCOL/STATE messages. We allocate 10 unused
bits in word 8 of the said message for this purpose, and introduce a
new capability bit, TIPC_BCAST_STATE_NACK in order to keep the change
backwards compatible.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02 17:10:24 -07:00
David Howells
00b5407e42 rxrpc: Fix uninitialised variable warning
Fix the following uninitialised variable warning:

../net/rxrpc/call_event.c: In function 'rxrpc_process_call':
../net/rxrpc/call_event.c:879:58: warning: 'error' may be used uninitialized in this function [-Wmaybe-uninitialized]
    _debug("post net error %d", error);
                                                          ^

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 22:39:44 +01:00
Arnd Bergmann
30787a4170 rxrpc: fix undefined behavior in rxrpc_mark_call_released
gcc -Wmaybe-initialized correctly points out a newly introduced bug
through which we can end up calling rxrpc_queue_call() for a dead
connection:

net/rxrpc/call_object.c: In function 'rxrpc_mark_call_released':
net/rxrpc/call_object.c:600:5: error: 'sched' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This sets the 'sched' variable to zero to restore the previous
behavior.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: f5c17aaeb2 ("rxrpc: Calls should only have one terminal state")
Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 22:39:44 +01:00
Nikolay Aleksandrov
b6cb5ac833 net: bridge: add per-port multicast flood flag
Add a per-port flag to control the unknown multicast flood, similar to the
unknown unicast flood flag and break a few long lines in the netlink flag
exports.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 22:48:33 -07:00
Nikolay Aleksandrov
8addd5e7d3 net: bridge: change unicast boolean to exact pkt_type
Remove the unicast flag and introduce an exact pkt_type. That would help us
for the upcoming per-port multicast flood flag and also slightly reduce the
tests in the input fast path.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 22:48:33 -07:00
Roopa Prabhu
d297653dd6 rtnetlink: fdb dump: optimize by saving last interface markers
fdb dumps spanning multiple skb's currently restart from the first
interface again for every skb. This results in unnecessary
iterations on the already visited interfaces and their fdb
entries. In large scale setups, we have seen this to slow
down fdb dumps considerably. On a system with 30k macs we
see fdb dumps spanning across more than 300 skbs.

To fix the problem, this patch replaces the existing single fdb
marker with three markers: netdev hash entries, netdevs and fdb
index to continue where we left off instead of restarting from the
first netdev. This is consistent with link dumps.

In the process of fixing the performance issue, this patch also
re-implements fix done by
commit 472681d57a ("net: ndo_fdb_dump should report -EMSGSIZE to rtnl_fdb_dump")
(with an internal fix from Wilson Kok) in the following ways:
- change ndo_fdb_dump handlers to return error code instead
of the last fdb index
- use cb->args strictly for dump frag markers and not error codes.
This is consistent with other dump functions.

Below results were taken on a system with 1000 netdevs
and 35085 fdb entries:
before patch:
$time bridge fdb show | wc -l
15065

real    1m11.791s
user    0m0.070s
sys 1m8.395s

(existing code does not return all macs)

after patch:
$time bridge fdb show | wc -l
35085

real    0m2.017s
user    0m0.113s
sys 0m1.942s

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 16:56:15 -07:00