network interfaces limited to 32 transmit segments, there
are two known issues.
The more serious one is that for an I/O of slightly less than 64K,
the net device driver prepends an ethernet header, resulting in a
TSO segment slightly larger than 64K. Since m_defrag() copies this
into 33 mbuf clusters, the transmit fails with EFBIG.
A tester indicated observing a similar failure using iSCSI.
The second less critical problem is that the network
device driver must copy the mbuf chain via m_defrag()
(m_collapse() is not sufficient), resulting in measurable overhead.
This patch reduces the default size of if_hw_tsomax
slightly, so that the first issue is avoided.
Fixing the second issue will require a way for the
network device driver to inform tcp_output() that it
is limited to 32 transmit segments.
Reported and tested by: csforgeron@gmail.com, markus.gebert@hostpoint.ch
MFC after: 2 weeks
was stacked on top of a network interface that set if_hw_tsomax,
tcp_output() would see the default value instead of the value
set by the network interface. This patch modifies vlan so that
it sets if_hw_tsomax to the value of the parent interface.
Reviewed by: glebius
MFC after: 2 weeks
was stacked on top of network interfaces that set if_hw_tsomax,
tcp_output() would see the default value instead of the value
set by the network interface(s). This patch modifies lagg so that
it sets if_hw_tsomax to the minimum of the value(s) for the
underlying network interfaces.
Reviewed by: glebius
MFC after: 2 weeks
This KASSERT() existed as a sanity check that upper layers in the network
stack (e.g. inet, inet6) had released their reference to the underlying
driver's multicast memberships (ifmultiaddr{}). However it assumes the
lifecycle of the driver membership corresponds to the lifecycle of the
network layer membership.
In the submitter's case, ieee80211_ioctl_updatemulti() attempts to
reprogram the (parent, physical) ifnet{} memberships in response
to a change in membership on the (child, virtual) VAP ifnet, using
a batched update mechanism. These updates happen independently from
the network layer, causing a "false negative" assertion failure.
There are possibly other use cases where this KASSERT() may be triggered
by other networking stack activity (e.g. where a nesting relationship
exists between multiple ifnet{} instances). This suggests that further
review of FreeBSD's approach to nested ifnet relationships is needed.
MFC after: 6 weeks
Submitted by: adrian@
The m_tag struct does not know about vnet context and the pf_mtag_free()
callback is called unaware of current vnet. This causes a panic.
Reviewed by: Nikos Vassiliadis, trociny@
ifi_oqdrops. This is a temporary workaround until ifqueue(9) vanishes.
While here, remove the pointless ifi_vhid assignment. It has
sense only when we are exporting ifaddrs, not ifnets.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
linking NIC Receive Side Scaling (RSS) to the network stack's
connection-group implementation. This prototype (and derived patches)
are in use at Juniper and several other FreeBSD-using companies, so
despite some reservations about its maturity, merge the patch to the
base tree so that it can be iteratively refined in collaboration rather
than maintained as a set of gradually diverging patch sets.
(1) Merge a software implementation of the Toeplitz hash specified in
RSS implemented by David Malone. This is used to allow suitable
pcbgroup placement of connections before the first packet is
received from the NIC. Software hashing is generally avoided,
however, due to high cost of the hash on general-purpose CPUs.
(2) In in_rss.c, maintain authoritative versions of RSS state intended
to be pushed to each NIC, including keying material, hash
algorithm/ configuration, and buckets. Provide software-facing
interfaces to hash 2- and 4-tuples for IPv4 and IPv6 using both
the RSS standardised Toeplitz and a 'naive' variation with a hash
efficient in software but with poor distribution properties.
Implement rss_m2cpuid()to be used by netisr and other load
balancing code to look up the CPU on which an mbuf should be
processed.
(3) In the Ethernet link layer, allow netisr distribution using RSS as
a source of policy as an alternative to source ordering; continue
to default to direct dispatch (i.e., don't try and requeue packets
for processing on the 'right' CPU if they arrive in a directly
dispatchable context).
(4) Allow RSS to control tuning of connection groups in order to align
groups with RSS buckets. If a packet arrives on a protocol using
connection groups, and contains a suitable hardware-generated
hash, use that hash value to select the connection group for pcb
lookup for both IPv4 and IPv6. If no hardware-generated Toeplitz
hash is available, we fall back on regular PCB lookup risking
contention rather than pay the cost of Toeplitz in software --
this is a less scalable but, at my last measurement, faster
approach. As core counts go up, we may want to revise this
strategy despite CPU overhead.
Where device drivers suitably configure NICs, and connection groups /
RSS are enabled, this should avoid both lock and line contention during
connection lookup for TCP. This commit does not modify any device
drivers to tune device RSS configuration to the global RSS
configuration; patches are in circulation to do this for at least
Chelsio T3 and Intel 1G/10G drivers. Currently, the KPI for device
drivers is not particularly robust, nor aware of more advanced features
such as runtime reconfiguration/rebalancing. This will hopefully prove
a useful starting point for refinement.
No MFC is scheduled as we will first want to nail down a more mature
and maintainable KPI/KBI for device drivers.
Sponsored by: Juniper Networks (original work)
Sponsored by: EMC/Isilon (patch update and merge)
AppleTalk was a network transport protocol for Apple Macintosh devices
in 80s and then 90s. Starting with Mac OS X in 2000 the AppleTalk was
a legacy protocol and primary networking protocol is TCP/IP. The last
Mac OS X release to support AppleTalk happened in 2009. The same year
routing equipment vendors (namely Cisco) end their support.
Thus, AppleTalk won't be supported in FreeBSD 11.0-RELEASE.
IPX was a network transport protocol in Novell's NetWare network operating
system from late 80s and then 90s. The NetWare itself switched to TCP/IP
as default transport in 1998. Later, in this century the Novell Open
Enterprise Server became successor of Novell NetWare. The last release
that claimed to still support IPX was OES 2 in 2007. Routing equipment
vendors (e.g. Cisco) discontinued support for IPX in 2011.
Thus, IPX won't be supported in FreeBSD 11.0-RELEASE.
interface, in the r241616 a crutch was provided. It didn't work well, and
finally we decided that it is time to break ABI and simply make if_baudrate
a 64-bit value. Meanwhile, the entire struct if_data was reviewed.
o Remove the if_baudrate_pf crutch.
o Make all fields of struct if_data fixed machine independent size. The
notion of data (packet counters, etc) are by no means MD. And it is a
bug that on amd64 we've got a 64-bit counters, while on i386 32-bit,
which at modern speeds overflow within a second.
This also removes quite a lot of COMPAT_FREEBSD32 code.
o Give 16 bit for the ifi_datalen field. This field was provided to
make future changes to if_data less ABI breaking. Unfortunately the
8 bit size of it had effectively limited sizeof if_data to 256 bytes.
o Give 32 bits to ifi_mtu and ifi_metric.
o Give 64 bits to the rest of fields, since they are counters.
__FreeBSD_version bumped.
Discussed with: emax
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
after r262763 it started to return locked mutexes to UMA. To fix that,
conditionally unlock the mutex in the destructor.
Tested by: "Sergey V. Dyatko" <sergey.dyatko@gmail.com>
- Use counter(9) for rt_pksent (former rt_rmx.rmx_pksent). This
removes another cache trashing ++ from packet forwarding path.
- Create zini/fini methods for the rtentry UMA zone. Via initialize
mutex and counter in them.
- Fix reporting of rmx_pksent to routing socket.
- Fix netstat(1) to report "Use" both in kvm(3) and sysctl(3) mode.
The change is mostly targeted for stable/10 merge. For head,
rt_pksent is expected to just disappear.
Discussed with: melifaro
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
RADIX_NODE_HEAD_LOCK as grabbing the write lock,
but RADIX_NODE_HEAD_LOCK_ASSERT as checking the read lock.
Submitted by: Vijay Singh <vijju.singh at gmail.com>
MFC after: 1 month
were primarily used to size the sysctl name list macros that were removed
in r254295. A few other constants either did not have an associated
sysctl node, or the associated node used OID_AUTO instead.
PR: ports/184525 (exp-run)
tested and is unfinished. However, I've tested my version,
it works okay. As before it is unfinished: timeout aren't
driven by TCP session state. To enable the HASH_ALL mode,
one needs in kernel config:
options FLOWTABLE_HASH_ALL
o Reduce the alignment on flentry to 64 bytes. Without
the FLOWTABLE_HASH_ALL option, twice less memory would
be consumed by flows.
o API to ip_output()/ip6_output() got even more thin: 1 liner.
o Remove unused unions. Simply use fle->f_key[].
o Merge all IPv4 code into flowtable_lookup_ipv4(), and do same
flowtable_lookup_ipv6(). Stop copying data to on stack
sockaddr structures, simply use key[] on stack.
o Move code from flowtable_lookup_common() that actually works
on insertion into flowtable_insert().
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
- netmap pipes, providing bidirectional blocking I/O while moving
100+ Mpps between processes using shared memory channels
(no mistake: over one hundred million. But mind you, i said
*moving* not *processing*);
- kqueue support (BHyVe needs it);
- improved user library. Just the interface name lets you select a NIC,
host port, VALE switch port, netmap pipe, and individual queues.
The upcoming netmap-enabled libpcap will use this feature.
- optional extra buffers associated to netmap ports, for applications
that need to buffer data yet don't want to make copies.
- segmentation offloading for the VALE switch, useful between VMs.
and a number of bug fixes and performance improvements.
My colleagues Giuseppe Lettieri and Vincenzo Maffione did a substantial
amount of work on these features so we owe them a big thanks.
There are some external repositories that can be of interest:
https://code.google.com/p/netmap
our public repository for netmap/VALE code, including
linux versions and other stuff that does not belong here,
such as python bindings.
https://code.google.com/p/netmap-libpcap
a clone of the libpcap repository with netmap support.
With this any libpcap client has access to most netmap
feature with no recompilation. E.g. tcpdump can filter
packets at 10-15 Mpps.
https://code.google.com/p/netmap-ipfw
a userspace version of ipfw+dummynet which uses netmap
to send/receive packets. Speed is up in the 7-10 Mpps
range per core for simple rulesets.
Both netmap-libpcap and netmap-ipfw will be merged upstream at some
point, but while this happens it is useful to have access to them.
And yes, this code will be merged soon. It is infinitely better
than the version currently in 10 and 9.
MFC after: 3 days
insert flow entry. During the route lookup the critical section is
exited. It may happen, that after route lookup we will be executed
on an other CPU that already has such flowentry. Before this change
we simply freed the flowentry and returned to ip_output() with
failure.
Actually there is nothing wrong with using previously allocated
flow entry, updating it properly. Thus, make flowentry_insert()
return the new either old fle, and make use of it.
Count reuses as "collisions" and real inserts as "inserts".
Reviewed by: adrian
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
race prone. Some just gather statistics, but some are later used in
different calculations.
A real problem was the race provoked underflow of the states_cur counter
on a rule. Once it goes below zero, it wraps to UINT32_MAX. Later this
value is used in pf_state_expires() and any state created by this rule
is immediately expired.
Thus, make fields states_cur, states_tot and src_nodes of struct
pf_rule be counter(9)s.
Thanks to Dennis for providing me shell access to problematic box and
his help with reproducing, debugging and investigating the problem.
Thanks to: Dennis Yusupoff <dyr smartspb.net>
Also reported by: dumbbell, pgj, Rambler
Sponsored by: Nginx, Inc.
Some of the collisions that are occuring are due to flowtable lookups
that succeed but have an invalid lle - typically because the L2 adjacency
lookup hasn't completed. This would lead to a follow-up insert which
would then fail (ie, collision) and the code would fall through to doing
a slow-path L2/L3 lookup in the netinet/netinet6 code.
This patch simply aborts storing a new flowtable entry if the lle isn't
yet valid.
Whilst I'm here, add a new pcpu counter for the item so the number of
failures can be tracked separately from generic "collisions."
Reviewed by: glebius
MFC after: 10 days
Sponsored by: Netflix, Inc.
and probably is a leftover from first prototyping by Kip. The
non-pcpu implementation used mutexes, so it doubtfully worked
better than simple routing lookup.
o Use UMA_ZONE_PCPU zone for pointers instead of [MAXCPU] arrays,
use zpcpu_get() to access data in there.
o Substitute own single list implementation with SLIST(). This
has two functional side effects:
- new flows go into head of a list, before they went to tail.
- a bug when incorrect flow was deleted in flow cleaner is
fixed.
o Due to cache line alignment, there is no reason to keep
different zones for IPv4 and IPv6 flows. Both consume one
cache line, real size of allocation is equal.
o Rely on that f_hash, f_rt, f_lle are stable during fle
lifetime, remove useless volatile quilifiers.
o More INET/INET6 splitting.
Reviewed by: adrian
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
- ip_output() and ip_output6() simply call flowtable_lookup(),
passing mbuf and address family. That's the only code under
#ifdef FLOWTABLE in the protocols code now.
o Revamp statistics gathering and export.
- Remove hand made pcpu stats, and utilize counter(9).
- Snapshot of statistics is available via 'netstat -rs'.
- All sysctls are moved into net.flowtable namespace, since
spreading them over net.inet isn't correct.
o Properly separate at compile time INET and INET6 parts.
o General cleanup.
- Remove chain of multiple flowtables. We simply have one for
IPv4 and one for IPv6.
- Flowtables are allocated in flowtable.c, symbols are static.
- With proper argument to SYSINIT() we no longer need flowtable_ready.
- Hash salt doesn't need to be per-VNET.
- Removed rudimentary debugging, which use quite useless in dtrace era.
The runtime behavior of flowtable shouldn't be changed by this commit.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
in the sysctl_root().
Note: SYSCTL_VNET_* macros can be removed as well. All is
needed to virtualize a sysctl oid is set CTLFLAG_VNET on it.
But for now keep macros in place to avoid large code churn.
Sponsored by: Nginx, Inc.
callback providers. link_init_sdl() function can be used to
fill most of the parameters. Use caller stack instead of
allocation / freing memory for each request. Do not drop support
for extra-long (probably non-existing) link-layer protocols by
introducing link_alloc_sdl() (used by if_resolvemulti() callback)
and link_free_sdl() (used by caller).
Since this change breaks KBI, MFC requires slightly different approach
(link_init_sdl() auto-allocating buffer if necessary to handle cases
with unmodified if_resolvemulti() callers).
MFC after: 2 weeks
has the same prefix as some other alias on the same interface, use
newly-added rt_addrmsg() instead of hand-rolled in_addralias_rtmsg().
This eliminates the following rtsock messages:
Pinned RTM_ADD for prefix (for alias addition).
Pinned RTM_DELETE for prefix (for alias withdrawal).
Example (got 10.0.0.1/24 on vlan4, playing with 10.0.0.2/24):
before commit, addition:
got message of size 116 on Fri Jan 10 14:13:15 2014
RTM_NEWADDR: address being added to iface: len 116, metric 0, flags:
sockaddrs: <NETMASK,IFP,IFA,BRD>
255.255.255.0 vlan4:8.0.27.c5.29.d4 10.0.0.2 10.0.0.255
got message of size 192 on Fri Jan 10 14:13:15 2014
RTM_ADD: Add Route: len 192, pid: 0, seq 0, errno 0, flags:<UP,PINNED>
locks: inits:
sockaddrs: <DST,GATEWAY,NETMASK>
10.0.0.0 10.0.0.2 (255) ffff ffff ff
after commit, addition:
got message of size 116 on Fri Jan 10 13:56:26 2014
RTM_NEWADDR: address being added to iface: len 116, metric 0, flags:
sockaddrs: <NETMASK,IFP,IFA,BRD>
255.255.255.0 vlan4:8.0.27.c5.29.d4 14.0.0.2 14.0.0.255
before commit, wihdrawal:
got message of size 192 on Fri Jan 10 13:58:59 2014
RTM_DELETE: Delete Route: len 192, pid: 0, seq 0, errno 0, flags:<UP,PINNED>
locks: inits:
sockaddrs: <DST,GATEWAY,NETMASK>
10.0.0.0 10.0.0.2 (255) ffff ffff ff
got message of size 116 on Fri Jan 10 13:58:59 2014
RTM_DELADDR: address being removed from iface: len 116, metric 0, flags:
sockaddrs: <NETMASK,IFP,IFA,BRD>
255.255.255.0 vlan4:8.0.27.c5.29.d4 10.0.0.2 10.0.0.255
adter commit, withdrawal:
got message of size 116 on Fri Jan 10 14:14:11 2014
RTM_DELADDR: address being removed from iface: len 116, metric 0, flags:
sockaddrs: <NETMASK,IFP,IFA,BRD>
255.255.255.0 vlan4:8.0.27.c5.29.d4 10.0.0.2 10.0.0.255
Sending both RTM_ADD/RTM_DELETE messages to rtsock is completely wrong
(and requires some hacks to keep prefix in route table on RTM_DELETE).
I've tested this change with quagga (no change) and bird (*).
bird alias handling is already broken in *BSD sysdep code, so nothing
changes here, too.
I'm going to MFC this change if there will be no complains about behavior
change.
While here, fix some style(9) bugs introduced by r260488
(pointed by glebius and bde).
Sponsored by: Yandex LLC
MFC after: 4 weeks
Adding/deleting interface addresses involves access to 3 different subsystems,
int different parts of code. Each call can fail, so reporting successful
operation by rtsock in the middle of the process error-prone.
Further split routing notification API and actual rtsock calls via creating
public-available rt_addrmsg() / rt_routemsg() functions with "private"
rtsock_* backend.
MFC after: 2 weeks
Remove old bits of data concat for 'ascii' field.
Remove special SIOCGIFSTATUS handling from if.c (which Coverity yells at).
Reported by: Coverity
Coverity CID: 1147174
MFC after: 2 weeks
Most relevant features:
- netmap emulation on any NIC, even those without native netmap support.
On the ixgbe we have measured about 4Mpps/core/queue in this mode,
which is still a lot more than with sockets/bpf.
- seamless interconnection of VALE switch, NICs and host stack.
If you disable accelerations on your NIC (say em0)
ifconfig em0 -txcsum -txcsum
you can use the VALE switch to connect the NIC and the host stack:
vale-ctl -h valeXX:em0
allowing sharing the NIC with other netmap clients.
- THE USER API HAS SLIGHTLY CHANGED (head/cur/tail pointers
instead of pointers/count as before). This was unavoidable to support,
in the future, multiple threads operating on the same rings.
Netmap clients require very small source code changes to compile again.
On the plus side, the new API should be easier to understand
and the internals are a lot simpler.
The manual page has been updated extensively to reflect the current
features and give some examples.
This is the result of work of several people including Giuseppe Lettieri,
Vincenzo Maffione, Michio Honda and myself, and has been financially
supported by EU projects CHANGE and OPENLAB, from NetApp University
Research Fund, NEC, and of course the Universita` di Pisa.
it performs exact match search, regardless of netmask existance.
This simplifies most of rnh_lookup() consumers.
Fix panic triggered by deleting non-existent host route.
PR: kern/185092
Submitted by: Nikolay Denev <ndenev at gmail.com>
MFC after: 1 month
bits of the flowid as each other, resulting in a poor distribution of
packets among queues in certain cases. Work around this by adding a
set of sysctls for controlling a bit-shift on the flowid when doing
multi-port aggrigation in lagg and lacp. By default, lagg/lacp will
now use bits 16 and higher instead of 0 and higher.
Reviewed by: max
Obtained from: Netflix
MFC after: 3 days
most often used with network interfaces.
The SFF-8472 standard defines the information that can be retrieved
from an optic or a copper cable plugged into a NIC, most often
referred to as SFP+. Examples of values that can be read
include the cable vendor's name, part number, date of manufacture
as well as running data such as temperature, voltage and tx
and rx power.
Copious comments on how to use these values with an I2C interface
are given in the header file itself.
MFC after: 2 weeks
In its stead use the Solaris / illumos approach of emulating '-' (dash)
in probe names with '__' (two consecutive underscores).
Reviewed by: markj
MFC after: 3 weeks
option, unbreak the lock tracing release semantic by embedding
calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
version of the releasing functions for mutex, rwlock and sxlock.
Failing to do so skips the lockstat_probe_func invokation for
unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
kernel compiled without lock debugging options, potentially every
consumer must be compiled including opt_kdtrace.h.
Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
is linked there and it is only used as a compile-time stub [0].
[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested. As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while. Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].
Sponsored by: EMC / Isilon storage division
Discussed with: rstone
[0] Reported by: rstone
[1] Discussed with: philip
- Removed pf_remove_src_node().
- Introduce pf_unlink_src_node() and pf_unlink_src_node_locked().
These function do not proceed with freeing of a node, just disconnect
it from storage.
- New function pf_free_src_nodes() works on a list of previously
disconnected nodes and frees them.
- Utilize new API in pf_purge_expired_src_nodes().
In collaboration with: Kajetan Staszkiewicz <kajetan.staszkiewicz innogames.de>
Sponsored by: InnoGames GmbH
Sponsored by: Nginx, Inc.
parts and global parts.
- Since global parts appeared to be only mutex initializations, just
abandon them and use MTX_SYSINIT() instead.
- Kill my incorrect VNET_FOREACH() iterator and instead use correct
approach with VNET_SYSINIT().
Submitted by: Nikos Vassiliadis <nvass gmx.com>
Reviewed by: trociny
assigned by the IEEE. This file includes documentation on how developers
must carve up the space as well as an initial allocation for bhyve.
Sponsored by: The FreeBSD Foundation
provide function ifa_switch_loopback_route() that will be used in case when
an interface address used for a loopback route goes away, but we have another
interface address with same address value and want to preserve loopback
route.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
default from the very beginning. It was placed in wrong namespace
net.link.ether, originally it had been at another wrong namespace. It was
incorrectly documented at incorrect manual page arp(8). Since new-ARP commit,
the tunable have been consulted only on route addition, and ignored on route
deletion. Behaviour of a system with tunable turned off is not fully correct,
and has no advantages comparing to normal behavior.
This includes the following:
- use separate memory regions for VALE ports
- locking fixes
- some simplifications in the NIC-specific routines
- performance improvements for the VALE switch
- some new features in the pkt-gen test program
- documentation updates
There are small API changes that require programs to be recompiled
(NETMAP_API has been bumped so you will detect old binaries at runtime).
In particular:
- struct netmap_slot now is 16 bytes to support an extra pointer,
which may save one data copy when using VALE ports or VMs;
- the struct netmap_if has two extra fields;
MFC after: 3 days
rather than just void *.
Then, as part of this, convert a couple of mbuf m->m_data accesses
to mtod(m, const void *).
Reviewed by: markm
Approved by: security-officer (delphij)
Sponsored by: Netflix, Inc.
and ordering related variables, fields and locks next to each
other. Add more comments to variables.
Over time 'ifnet' has accumlated a lot of additional pointers and
functionality in an unstructured way making it quite hard to read
and understand while obfuscating relationships between fields and
variables.
Quantify the structure size and how bloated it has become.
This is only a mechanical change in preparation for upcoming
work to make ifnet opaque to drivers and to separate out the
interface queuing.
Sponsored by: The FreeBSD Foundation
from net/if_var to it own new net/ifq.h.
For now net/ifq.h is unconditionally included through net/if_var.h.
This is a mechanical change in preparation to make struct ifnet and
the individual interface queue mechanisms opaque.
Discussed with: glebius
Sponsored by: The FreeBSD Foundation
from if.h.
- Remove unnecessary includes and declarations from if.h
- Remove unnecessary includes and declarations from if_var.h [1]
- Mark some declarations that are about to be removed in near
future with comments, explaning why this declaration is still
necessary.
- Protect eventhandler declarations with #ifdef SYS_EVENTHANDLER_H.
Obtained from: bdeBSD [1]
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
bpf(4) and vlan(4) related event declarations to bpf.h and
if_vlan_var.h. To avoid dependency on eventhandler.h, protect
these declarations with ifdef SYS_EVENTHANDLER_H.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
in net, to avoid compatibility breakage for no sake.
The future plan is to split most of non-kernel parts of
pfvar.h into pf.h, and then make pfvar.h a kernel only
include breaking compatibility.
Discussed with: bz
- Provide pf_altq.h that has only stuff needed for ALTQ.
- Start pf.h, that would have all constant values and
eventually non-kernel structures.
- Build ALTQ w/o pfvar.h, include if_var.h, that before
came via pollution.
- Build tcpdump w/o pfvar.h.
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
to this event, adding if_var.h to files that do need it. Also, include
all includes that now are included due to implicit pollution via if_var.h
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
created after each other e.g.
ifconfig tap0
ifconfig vmnet0
<panic>
Appears to be a cut'n'paste error from the tap code to the vmnet
code where the name string wasn't updated in the call to make_dev().
Reviewed by: glebius
MFC after: 3 days
Usual symptoms are messages like
rn_delete: inconsistent annotation
rn_addmask: mask impossibly already in tree
or inability to flush/delete particular prefix in ipfw table.
Changes:
* Assume 32 bytes as maximum radix key length
* Remove rn_init()
* Statically allocate rn_ones/rn_zeroes
* Make separate mask tree for each "normal" tree instead of system global one
* Remove "optimization" on masks reusage and key zeroying
* Change rn_addmask() arguments to accept tree pointer (no users in base)
PR: kern/182851, kern/169206, kern/135476, kern/134531
Found by: Slawa Olhovchenkov <slw@zxy.spb.ru>
MFC after: 2 weeks
Reviewed by: glebius
Sponsored by: Yandex LLC
four counters to struct ifaddr. This kills '+=' on a variables shared
between processors for every packet.
- Nuke struct if_data from struct ifaddr.
- In ip_input() do not put a reference on ifaddr, instead update statistics
right now in place and do IN_IFADDR_RUNLOCK(). These removes atomic(9)
for every packet. [1]
- To properly support NET_RT_IFLISTL sysctl used by getifaddrs(3), in
rtsock.c fill if_data fields using counter_u64_fetch().
- Accidentially fix bug in COMPAT_32 version of NET_RT_IFLISTL, which
took if_data not from the ifaddr, but from ifaddr's ifnet. [2]
Submitted by: melifaro [1], pluknet[2]
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
and there are ifnets, that do that via counter(9). Provide a flag that
would skip cache line trashing '+=' operation in ether_input().
Sponsored by: Netflix
Sponsored by: Nginx, Inc.
Reviewed by: melifaro, adrian
Approved by: re (marius)
been tested. With all sources turned on, this unlocks itself in
a couple of seconds! That is no my box, and there is no guarantee
that this will be the case everywhere.
* Cut debug prints.
* Use the same locks/mutexes all the way through.
* Be a tad more conservative about entropy estimates.
Contains:
* Refactor the hardware RNG CPU instruction sources to feed into
the software mixer. This is unfinished. The actual harvesting needs
to be sorted out. Modified by me (see below).
* Remove 'frac' parameter from random_harvest(). This was never
used and adds extra code for no good reason.
* Remove device write entropy harvesting. This provided a weak
attack vector, was not very good at bootstrapping the device. To
follow will be a replacement explicit reseed knob.
* Separate out all the RANDOM_PURE sources into separate harvest
entities. This adds some secuity in the case where more than one
is present.
* Review all the code and fix anything obviously messy or inconsistent.
Address som review concerns while I'm here, like rename the pseudo-rng
to 'dummy'.
Submitted by: Arthur Mesh <arthurmesh@gmail.com> (the first item)
extremely outdated, and I doubt that it was ever used for ifnet drivers.
It was used for AF_INET sockets in pre-FreeBSD time.
Approved by: re (hrs)
Sponsored by: Nginx, Inc.
transmission which could be tricked into rounding up to the nearest
page size, leaking up to a page of kernel memory. [13:11]
In IPv6 and NetATM, stop SIOCSIFADDR, SIOCSIFBRDADDR, SIOCSIFDSTADDR
and SIOCSIFNETMASK at the socket layer rather than pass them on to the
link layer without validation or credential checks. [SA-13:12]
Prevent cross-mount hardlinks between different nullfs mounts of the
same underlying filesystem. [SA-13:13]
Security: CVE-2013-5666
Security: FreeBSD-SA-13:11.sendfile
Security: CVE-2013-5691
Security: FreeBSD-SA-13:12.ifioctl
Security: CVE-2013-5710
Security: FreeBSD-SA-13:13.nullfs
Approved by: re
the rest by me.
o Namespace cleanup; the Yarrow name is now restricted to where it
really applies; this is in anticipation of being augmented or
replaced by Fortuna in the future. Fortuna is mentioned, but behind
#if logic, and is ignorable for now.
o The harvest queue is pulled out into its own modules.
o Entropy harvesting is emproved, both by being made more conservative,
and by separating (a bit!) the sources. Available entropy crumbs are
marginally improved.
o Selection of sources is made clearer. With recent revelations,
this will receive more work in the weeks and months to come.
Submitted by: Arthur Mesh (partly) <arthurmesh@gmail.com>
These were used to control/export dispatch policy but they're not anymore.
This commit cannot be MFC'ed to 9 because old netstat(9) binary relies
on such sysctl to work. On the other hand, there's no real reason to
keep'em around in 10.
We've been seeing lots of cache line contention (but not lock contention!)
in our workloads between the various TX and RX threads going on.
The write lock is only grabbed when configuration changes are made - which
are infrequent.
With this patch, the contention and cycles spent waiting for updates
disappear.
Sponsored by: Netflix, Inc.
features. The changes in particular are:
o Remove rarely used "header" pointer and replace it with a 64bit protocol/
layer specific union PH_loc for local use. Protocols can flexibly overlay
their own 8 to 64 bit fields to store information while the packet is
worked on.
o Mechanically convert IP reassembly, IGMP/MLD and ATM to use pkthdr.PH_loc
instead of pkthdr.header.
o Extend csum_flags to 64bits to allow for additional future offload
information to be carried (e.g. iSCSI, IPsec offload, and others).
o Move the RSS hash type enumerator from abusing m_flags to its own 8bit
rsstype field. Adjust accessor macros.
o Add cosqos field to store Class of Service / Quality of Service information
with the packet. It is not yet supported in any drivers but allows us to
get on par with Cisco/Juniper in routing applications (plus MPLS QoS) with
a modernized ALTQ.
o Add four 8 bit fields l[2-5]hlen to store the relative header offsets
from the start of the packet. This is important for various offload
capabilities and to relieve the drivers from having to parse the packet
and protocol headers to find out location of checksums and other
information. Header parsing in drivers is a lot of copy-paste and
unhandled corner cases which we want to avoid.
o Add another flexible 64bit union to map various additional persistent
packet information, like ether_vtag, tso_segsz and csum fields.
Depending on the csum_flags settings some fields may have different usage
making it very flexible and adaptable to future capabilities.
o Restructure the CSUM flags to better signify their outbound (down the
stack) and inbound (up the stack) use. The CSUM flags used to be a bit
chaotic and rather poorly documented leading to incorrect use in many
places. Bring clarity into their use through better naming.
Compatibility mappings are provided to preserve the API. The drivers
can be corrected one by one and MFC'd without issue.
o The size of pkthdr stays the same at 48/56bytes (32/64bit architectures).
Sponsored by: The FreeBSD Foundation
The linked list of pfil hooks is changed to "chain" and this term
is applied consistently. The head_list remains with "list" term.
Add KASSERT to vnet_pfil_uninit().
Update and extend comments.
Reviewed by: eri (previous version)
LLAs on the member interfaces are actually harmless when the parent
interface does not have a LLA.
- Add net.link.bridge.allow_llz_overlap. This is a knob to allow LLAs on
a bridge and the member interfaces at the same time. The default is 0.
Pointed out by: ume
MFC after: 3 days
sysctl tree.
* Create a net.link.lagg.X.lacp node
* Add a debug node under that for tx_test and rx_test
* Add lacp_strict_mode, defaulting to 1
tx_test and rx_test are still a bitmap of unit numbers for now.
At some point it would be nice to create child nodes of the lagg bundle
for each sub-interface, and then populate those with various knobs
and statistics.
Sponsored by: Netflix
addresses added to the UUID generator using uuid_ether_add(). The
UUID generator keeps an arbitrary number of MAC addresses, under
the assumption that they are rarely removed (= uuid_ether_del()).
This achieves the following:
1. It brings up closer to having the network stack as a loadable
module.
2. It allows the UUID generator to filter MAC addresses for best
results (= highest chance of uniqeness).
3. MAC addresses can come from anywhere, irrespactive of whether
it's used for an interface or not.
A side-effect of the change is that when no MAC addresses have been
added, a random multicast MAC address is created once and re-used if
needed. Previusly, when a random MAC address was needed, it was
created for every call. Thus, a change in behaviour is introduced
for when no MAC addresses exist.
Obtained from: Juniper Networks, Inc.
Submitted by: adrian, zec
Fix multiple kernel panics when VIMAGE is enabled in the kernel.
These fixes are based on patches submitted by Adrian Chadd and Marko Zec.
(1) Set curthread->td_vnet to vnet0 in device_probe_and_attach() just before calling
device_attach(). This fixes multiple VIMAGE related kernel panics
when trying to attach Bluetooth or USB Ethernet devices because
curthread->td_vnet is NULL.
(2) Set curthread->td_vnet in if_detach(). This fixes kernel panics when detaching networking
interfaces, especially USB Ethernet devices.
(3) Use VNET_DOMAIN_SET() in ng_btsocket.c
(4) In ng_unref_node() set curthread->td_vnet. This fixes kernel panics
when detaching Netgraph nodes.
additions.
* Add some new tracing events to aid in debugging.
* Add in a debugging mode to drop transmit and received frames, specifically
to test whether seeing or hearing heartbeats correctly cause LACP to
drop the port.
* Add in (and make default) a strict LACP mode, which requires the
heartbeat on a port to be heard before it's used. Sometimes vendor ports
will hang but the link layer stays up, resulting in hung traffic.
* Add logging the number of link status flaps, again to aid in debugging
badly behaving switch ports.
* Calculate the lagg interface port speed as the multiple of the
configured ports, rather than the largest.
Obtained from: Netflix
MFC after: 2 weeks
is initialized with !ND6_IFF_AUTO_LINKLOCAL && !ND6_IFF_ACCEPT_RTADV
regardless of net.inet6.ip6.accept_rtadv and net.inet6.ip6.auto_linklocal.
To configure an autoconfigured link-local address (RFC 4862), the
following rc.conf(5) configuration can be used:
ifconfig_bridge0_ipv6="inet6 auto_linklocal"
- if_bridge(4) now removes IPv6 addresses on a member interface to be
added when the parent interface or one of the existing member
interfaces has an IPv6 address. if_bridge(4) merges each link-local
scope zone which the member interfaces form respectively, so it causes
address scope violation. Removal of the IPv6 addresses prevents it.
- if_lagg(4) now removes IPv6 addresses on a member interfaces
unconditionally.
- Set reasonable flags to non-IPv6-capable interfaces. [*]
Submitted by: rpaulo [*]
MFC after: 1 week
in FBSD 8.0, interface routes have been returened to the
applications without the RTF_GATEWAY bit. This incompatibility
has caused some issues with Zebra, Qugga and the like.
This patch provides the RTF_GATEWAY flag bit in returned interface
routes so to behave similarly to pre 8.0 systems.
Reviewed by: hrs
Verified by: mackn at opendns dot com
inactive when upper layer tries to transmit packet. This
gives better feedback and meaningful errors for applications.
MFC after: 2 weeks
Reviewed by: thompsa
limited in the amount of data they can handle at once.
Drivers can set ifp->if_hw_tsomax before calling ether_ifattach() to
change the limit.
The lowest allowable size is IP_MAXPACKET / 8 (8192 bytes) as anything
less wouldn't be very useful anymore. The upper limit is still at
IP_MAXPACKET (65536 bytes). Raising it requires further auditing of
the IPv4/v6 code path's as the length field in the IP header would
overflow leading to confusion in firewalls and others packet handler on
the real size of the packet.
The placement into "struct ifnet" is a bit hackish but the best place
that was found. When the stack/driver boundary is updated it should
be handled in a better way.
Submitted by: cperciva (earlier version)
Reviewed by: cperciva
Tested by: cperciva
MFC after: 1 week (using spare struct members to preserve ABI)
- the VALE switch now support up to 254 destinations per switch,
unicast or broadcast (multicast goes to all ports).
- we can attach hw interfaces and the host stack to a VALE switch,
which means we will be able to use it more or less as a native bridge
(minor tweaks still necessary).
A 'vale-ctl' program is supplied in tools/tools/netmap
to attach/detach ports the switch, and list current configuration.
- the lookup function in the VALE switch can be reassigned to
something else, similar to the pf hooks. This will enable
attaching the firewall, or other processing functions (e.g. in-kernel
openvswitch) directly on the netmap port.
The internal API used by device drivers does not change.
Userspace applications should be recompiled because we
bump NETMAP_API as we now use some fields in the struct nmreq
that were previously ignored -- otherwise, data structures
are the same.
Manpages will be committed separately.
The lagg(4) is often used to bond high speed links, so basic per-packet +=
on statistics cause cache misses and statistics loss.
Perfect solution would be to convert ifnet(9) to counters(9), but this
requires much more work, and unfortunately ABI change, so temporarily
patch lagg(4) manually.
We store counters in the softc, and once per second push their values
to legacy ifnet counters.
Sponsored by: Nginx, Inc.
reside on their own cache line to prevent false sharing with other
nearby structures, especially for those in the .bss segment.
NB: Those mutexes and rwlocks with variables next to them that get
changed on every invocation do not benefit from their own cache line.
Actually it may be net negative because two cache misses would be
incurred in those cases.
- Convert panic() to KASSERT.
- Remove superfluous cleaning of mbuf fields after allocation.
- Add comment on possible use of m_get2() here.
Sponsored by: Nginx, Inc.
and that can drive someone crazy. While m_get2() is young and not
documented yet, change its order of arguments to match m_getm2().
Sorry for churn, but better now than later.
Use RTM_PINNED flag to mark route as immutable.
Forbid deleting immutable routes without special rtrequest1_fib() flag.
Adding interface address with prefix already in route table is handled
by atomically deleting old prefix and adding interface one.
Discussed with: andre, eri
MFC after: 3 weeks
length packets, which was actually harmless.
Note that peers with different version of head/ may grow this
counter, but it is harmless - all pfsync data is processed.
Reported & tested by: Anton Yuzhaninov <citrin citrin.ru>
Sponsored by: Nginx, Inc
of helper functions:
- carp_master() - boolean function which is true if an address
is in the MASTER state.
- ifa_preferred() - boolean function that compares two addresses,
and is aware of CARP.
Utilize ifa_preferred() in ifa_ifwithnet().
The previous version of patch also changed source address selection
logic in jails using carp_master(), but we failed to negotiate this part
with Bjoern. May be we will approach this problem again later.
Reported & tested by: Anton Yuzhaninov <citrin citrin.ru>
Sponsored by: Nginx, Inc
of the newer drivers. The basic problem was
that the driver was pulling the mbuf off the
drbr ring and then when sending with xmit(), encounting
a full transmit ring. Thus the lower layer
xmit() function would return an error, and the
drivers would then append the data back on to the ring.
For TCP this is a horrible scenario sure to bring
on a fast-retransmit.
The fix is to use drbr_peek() to pull the data pointer
but not remove it from the ring. If it fails then
we either call the new drbr_putback or drbr_advance
method. Advance moves it forward (we do this sometimes
when the xmit() function frees the mbuf). When
we succeed we always call advance. The
putback will always copy the mbuf back to the top
of the ring. Note that the putback *cannot* be used
with a drbr_dequeue() only with drbr_peek(). We most
of the time, in putback, would not need to copy it
back since most likey the mbuf is still the same, but
sometimes xmit() functions will change the mbuf via
a pullup or other call. So the optimial case for
the single consumer is to always copy it back. If
we ever do a multiple_consumer (for lagg?) we
will need a test and atomic in the put back possibly
a seperate putback_mc() in the ring buf.
Reviewed by: jhb@freebsd.org, jlv@freebsd.org
Since ARP and routing are separated, "proxy only" entries
don't have any meaning, thus we don't need additional field
in sockaddr to pass SIN_PROXY flag.
New kernel is binary compatible with old tools, since sizes
of sockaddr_inarp and sockaddr_in match, and sa_family are
filled with same value.
The structure declaration is left for compatibility with
third party software, but in tree code no longer use it.
Reviewed by: ru, andre, net@
lle_event replaced arp_update_event after the ARP rewrite and ended up
in if_ether.h simply because arp_update_event used to be there too.
IPv6 neighbor discovery is going to grow lle_event support and this is a
good time to move it to if_llatbl.h.
The two in-tree consumers of this event - OFED and toecore - are not
affected.
Reviewed by: bz@
in from kernel-pppd which is long gone) so that ZFS and DTRACE play nice.
This is a horrible hack to get freefall to compile, and is in dire need
of reconciliation. This antique zlib-1.04 code needs to go away.
entering llentry_free(), and in case if we lose the race, we should simply
perform LLE_FREE_LOCKED(). Otherwise, if the race is lost by the thread
performing arptimer(), it will remove two references from the lle instead
of one.
Reported by: Ian FREISLICH <ianf clue.co.za>
cause kernel panics.
Add a flag to the bpf descriptor to indicate whether the hold buffer
is in use. In bpfread(), set the "hold buffer in use" flag before
dropping the descriptor lock during the call to bpf_uiomove().
Everywhere else the hold buffer is used or changed, wait while
the hold buffer is in use by bpfread(). Add a KASSERT in bpfread()
after re-acquiring the descriptor lock to assist uncovering any
additional hold buffer races.
- Deembed scope id in L3 address in in6_lltable_dump().
- Simplify scope id recovery in rtsock routines.
- Remove embedded scope id handling in ndp(8) and route(8) completely.
- Check V_deembed_scopeid before checking if sa_family == AF_INET6.
- Fix scope id handing in route(8)[2] and ifconfig(8).
Reported by: rpaulo[1], Mateusz Guzik[1], peter[2]
for bridge interface.
- If we found a collision we can break the loop - only one collision is
possible and one is exactly enough to need to renegerate.
Obtained from: WHEEL Systems
MFC after: 1 week
userland via routing socket or sysctl. This eliminates the following
KAME-specific sin6_scope_id handling routine from each userland utility:
sin6.sin6_scope_id = ntohs(*(u_int16_t *)&sin6.sin6_addr.s6_addr[2]);
This behavior can be controlled by net.inet6.ip6.deembed_scopeid. This is
set to 1 by default (sin6_scope_id will be filled in the kernel).
Reviewed by: bz
Instead, add protocol specific mbuf flags M_IP_NEXTHOP and
M_IP6_NEXTHOP. Use them to indicate that the mbuf's chain
contains the PACKET_TAG_IPFORWARD tag. And do a tag lookup
only when this flag is set.
Suggested by: andre
on checksums directly from mbuf flags. This simplifies code.
o Clear CSUM_IP from the mbuf in ip_fragment() if we did checksums in
hardware. Some driver may not announce CSUM_IP in theur if_hwassist,
although try to do checksums if CSUM_IP set on mbuf. Example is em(4).
o While here, consistently use CSUM_IP instead of its alias CSUM_DELAY_IP.
After this change CSUM_DELAY_IP vanishes from the stack.
Submitted by: Sebastian Kuzminsky <seb lineratesystems.com>
on the related functionality in the runtime via the sysctl variable
net.pfil.forward. It is turned off by default.
Sponsored by: Yandex LLC
Discussed with: net@
MFC after: 2 weeks
in network byte order. Any host byte order processing is
done in local variables and host byte order values are
never[1] written to a packet.
After this change a packet processed by the stack isn't
modified at all[2] except for TTL.
After this change a network stack hacker doesn't need to
scratch his head trying to figure out what is the byte order
at the given place in the stack.
[1] One exception still remains. The raw sockets convert host
byte order before pass a packet to an application. Probably
this would remain for ages for compatibility.
[2] The ip_input() still subtructs header len from ip->ip_len,
but this is planned to be fixed soon.
Reviewed by: luigi, Maxim Dounin <mdounin mdounin.ru>
Tested by: ray, Olivier Cochard-Labbe <olivier cochard.me>
filters (ipfw and PF) use the same ruleset with the same lock for both
AF_INET and AF_INET6 there is no need in more fine-grade locking.
However, it is possible to request personal lock by specifying
PFIL_FLAG_PRIVATE_LOCK flag in pfil_head structure (see pfil.9 for
more details).
Export PFIL lock via rw_lock(9)/rm_lock(9)-like API permitting pfil consumers
to use this lock instead of own lock. This help reducing locks on main
traffic path.
pfil_assert() is currently not implemented due to absense of rm_assert().
Waiting for some kind of r234648 to be merged in HEAD.
This change is part of bigger patch reducing routing locking.
Sponsored by: Yandex LLC
Reviewed by: glebius, ae
OK'd by: silence on net@
MFC after: 3 weeks
around the problem where high speed interfaces (such as ixgbe(4))
are not able to report real ifi_baudrate. bascially, take a spare
byte from struct if_data and use it to store ifi_baudrate power
factor. in other words,
real ifi_baudrate = ifi_baudrate * 10 ^ ifi_baudrate power factor
this should be backwards compatible with old binaries. use ixgbe(4)
as an example on how drivers would set ifi_baudrate power factor
Discussed with: kib, scottl, glebius
MFC after: 1 week
now use function calls:
if_clone_simple()
if_clone_advanced()
to initialize a cloner, instead of macros that initialize if_clone
structure.
Discussed with: brooks, bz, 1 year ago
- All packets in NETISR_IP queue are in net byte order.
- ip_input() is entered in net byte order and converts packet
to host byte order right _after_ processing pfil(9) hooks.
- ip_output() is entered in host byte order and converts packet
to net byte order right _before_ processing pfil(9) hooks.
- ip_fragment() accepts and emits packet in net byte order.
- ip_forward(), ip_mloopback() use host byte order (untouched actually).
- ip_fastforward() no longer modifies packet at all (except ip_ttl).
- Swapping of byte order there and back removed from the following modules:
pf(4), ipfw(4), enc(4), if_bridge(4).
- Swapping of byte order added to ipfilter(4), based on __FreeBSD_version
- __FreeBSD_version bumped.
- pfil(9) manual page updated.
Reviewed by: ray, luigi, eri, melifaro
Tested by: glebius (LE), ray (BE)
The base netmap pointer and offsets involved are provided by the kernel
side of the netmap interface and will have appropriate alignment.
Sponsored by: ADARA Networks
MFC After: 2 weeks
the CAM "enc" peripheral (part of ses(4)). Previously the two modules
used the same name, so only one was included in a linked kernel causing
enc0 to not be created if you added IPSEC to GENERIC. The new module
name follows the pattern of other network interfaces (e.g. "if_loop").
MFC after: 1 week
tree used it incorrectly, which lead to inaccurate overrated
if_obytes accounting. The drbr(9) used to update ifnet stats on
drbr_enqueue(), which is not accurate since enqueuing doesn't
imply successful processing by driver. Dequeuing neither mean
that. Most drivers also called drbr_stats_update() which did
accounting again, leading to doubled if_obytes statistics. And
in case of severe transmitting, when a packet could be several
times enqueued and dequeued it could have been accounted several
times.
o Thus, make drbr(9) API thinner. Now drbr(9) merely chooses between
ALTQ queueing or buf_ring(9) queueing.
- It doesn't touch the buf_ring stats any more.
- It doesn't touch ifnet stats anymore.
- drbr_stats_update() no longer exists.
o buf_ring(9) handles its stats itself:
- It handles br_drops itself.
- br_prod_bytes stats are dropped. Rationale: no one ever
reads them but update of a common counter on every packet
negatively affects performance due to excessive cache
invalidation.
- buf_ring_enqueue_bytes() reduced to buf_ring_enqueue(), since
we no longer account bytes.
o Drivers handle their stats theirselves: if_obytes, if_omcasts.
o mlx4(4), igb(4), em(4), vxge(4), oce(4) and ixv(4) no longer
use drbr_stats_update(), and update ifnet stats theirselves.
o bxe(4) was the most correct driver, it didn't call
drbr_stats_update(), thus it was the only driver accurate under
moderate load. Now it also maintains stats itself.
o ixgbe(4) had already taken stats from hardware, so just
- drop software stats updating.
- take multicast packet count from hardware as well.
o mxge(4) just no longer needs NO_SLOW_STATS define.
o cxgb(4), cxgbe(4) need no change, since they obtain stats
from hardware.
Reviewed by: jfv, gnn
