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.
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@
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>
llentry_free() and arptimer():
o Use callout_init_rw() for lle timeout, this allows us safely
disestablish them.
- This allows us to simplify the arptimer() and make it
race safe.
o Consistently use ifp->if_afdata_lock to lock access to
linked lists in the lle hashes.
o Introduce new lle flag LLE_LINKED, which marks an entry that
is attached to the hash.
- Use LLE_LINKED to avoid double unlinking via consequent
calls to llentry_free().
- Mark lle with LLE_DELETED via |= operation istead of =,
so that other flags won't be lost.
o Make LLE_ADDREF(), LLE_REMREF() and LLE_FREE_LOCKED() more
consistent and provide more informative KASSERTs.
The patch is a collaborative work of all submitters and myself.
PR: kern/165863
Submitted by: Andrey Zonov <andrey zonov.org>
Submitted by: Ryan Stone <rysto32 gmail.com>
Submitted by: Eric van Gyzen <eric_van_gyzen dell.com>
referenced within its timeout window. This change clears the LLE_VALID flag when an llentry
is removed from an interface's hash table and adds an extra check to the flowtable code
for the LLE_VALID flag in llentry to avoid retaining and using a stale reference.
Reviewed by: qingli@
MFC after: 2 weeks
interface is brought down, even though the interface address is still
valid. This patch maintains the permanent ARP entries as long as the
interface address (having the same prefix as that of the ARP entries)
is valid.
Reviewed by: delphij
MFC after: 5 days
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files. A better long-term solution is
still being considered. This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.
Changes reverted:
------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines
Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.
------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines
Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.
------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines
Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.
When a fast machine first brings up some non TCP networking program
it is quite possible that we will drop packets due to the fact that
only one packet can be held per ARP entry. This leads to packets
being missed when a program starts or restarts if the ARP data is
not currently in the ARP cache.
This code adds a new sysctl, net.link.ether.inet.maxhold, which defines
a system wide maximum number of packets to be held in each ARP entry.
Up to maxhold packets are queued until an ARP reply is received or
the ARP times out. The default setting is the old value of 1
which has been part of the BSD networking code since time
immemorial.
Expose the time we hold an incomplete ARP entry by adding
the sysctl net.link.ether.inet.wait, which defaults to 20
seconds, the value used when the new ARP code was added..
Reviewed by: bz, rpaulo
MFC after: 3 weeks
either find an existing entry, or allocate a new one. In the latter
case an entry would have flags, that were supplied as argument to
lla_lookup(). In case of an existing entry, flags aren't modified.
This lead to losing LLE_PUB and/or LLE_PROXY flags.
We should apply these flags either in lla_rt_output() or in the
in.c:in_lltable_lookup(). It seems to me that lla_rt_output() is
a more correct choice.
PR: kern/148784, kern/146539
Silence from: qingli, 5 days
prevented the link-layer entry from being freed.
In both in.c and in6.c (though that code path seems to be basically dead)
plug a reference leak in case of a pending callout being drained.
In if_ether.c consistently add a reference before resetting the callout
and in case we canceled a pending one remove the reference for that.
In the final case in arptimer, before freeing the expired entry, remove
the reference again and explicitly call callout_stop() to clear the active
flag.
In nd6.c:nd6_free() we are only ever called from the callout function and
thus need to remove the reference there as well before calling into
llentry_free().
In if_llatbl.c when freeing entire tables make sure that in case we cancel
a pending callout to remove the reference as well.
Reviewed by: qingli (earlier version)
MFC after: 10 days
Problem observed, patch tested by: simon on ipv6gw.f.o,
Christian Kratzer (ck cksoft.de),
Evgenii Davidov (dado korolev-net.ru)
PR: kern/144564
Configurations still affected: with options FLOWTABLE
- show all lltables [1] (optional flag to also show the llentries as well)
- show lltable <struct lltable *>
- show llentry <struct llentry *>
MFC after: 6 days
- add a name argument to flowtable_alloc for printing with ddb commands
- extend ddb commands to print destination address or 4-tuples
- don't parse ports in ulp header if FL_HASH_ALL is not passed
- add kern_flowtable_insert to enable more generic use of flowtable
(e.g. system calls for adding entries)
- don't hash loopback addresses
- cleanup whitespace
- keep statistics per-cpu for per-cpu flowtables to avoid cache line contention
- add sysctls to accumulate stats and report aggregate
MFC after: 7 days
IFF_POINTOPOINT link types. The reason was due to the routing
entry returned from the kernel covering the remote end is of an
interface type that does not support ARP. This patch fixes this
problem by providing a hint to the kernel routing code, which
indicates the prefix route instead of the PPP host route should
be returned to the caller. Since a host route to the local end
point is also added into the routing table, and there could be
multiple such instantiations due to multiple PPP links can be
created with the same local end IP address, this patch also fixes
the loopback route installation failure problem observed prior to
this patch. The reference count of loopback route to local end would
be either incremented or decremented. The first instantiation would
create the entry and the last removal would delete the route entry.
MFC after: 5 days
usable again with options VIMAGE kernels.
Submitted by: bz (the original version, probably identical to this one)
Reviewed by: many @ DevSummit Cambridge
MFC after: 3 days
- Interface link-local address is not reachable within the
node that owns the interface, this is due to the mismatch
in address scope as the result of the installed interface
address loopback route. Therefore for each interface
address loopback route, the rt_gateway field (of AF_LINK
type) will be used to track which interface a given
address belongs to. This will aid the address source to
use the proper interface for address scope/zone validation.
- The loopback address is not reachable. The root cause is
the same as the above.
- Empty nd6 entries are created for the IPv6 loopback addresses
only for validation reason. Doing so will eliminate as much
of the special case (loopback addresses) handling code
as possible, however, these empty nd6 entries should not
be returned to the userland applications such as the
"ndp" command.
Since both of the above issues contain common files, these
files are committed together.
Reviewed by: bz
MFC after: immediately
list/index locks, to protect link layer address tables. This avoids
lock order issues during interface teardown, but maintains the bug that
sysctl copy routines may be called while a non-sleepable lock is held.
Reviewed by: bz, kmacy
MFC after: 3 days
several critical bugs, including race conditions and lock order issues:
Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock. Either can be held to stablize the lists and indexes, but both
are required to write. This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions. As before, writes to
the interface list must occur from sleepable contexts.
Reviewed by: bz, julian
MFC after: 3 days
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.
Reviewed by: bz
Approved by: re (vimage blanket)
route is also being deleted, the link-layer address table
(arp or nd6) will flush those L2 llinfo entries that match
the removed prefix.
Reviewed by: kmacy
a locked route. Thus we have to use RTFREE_LOCKED(9) to get it unlocked
and rtfree(9)d rather than just rtfree(9)d.
Since the PR was filed, new places with the same problem were added
with new code. Also check that the rt is valid before freeing it
either way there.
PR: kern/129793
Submitted by: Dheeraj Reddy <dheeraj@ece.gatech.edu>
MFC after: 2 weeks
Committed from: Bugathon #6
