Commit Graph

23369 Commits

Author SHA1 Message Date
Joe Perches
55b1804c67 net/irda: Use static const char * const where possible
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 20:22:05 -07:00
Linus Torvalds
de8d4f5d75 Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  SUNRPC: Fix the NFSv4 and RPCSEC_GSS Kconfig dependencies
  statfs() gives ESTALE error
  NFS: Fix a typo in nfs_sockaddr_match_ipaddr6
  sunrpc: increase MAX_HASHTABLE_BITS to 14
  gss:spkm3 miss returning error to caller when import security context
  gss:krb5 miss returning error to caller when import security context
  Remove incorrect do_vfs_lock message
  SUNRPC: cleanup state-machine ordering
  SUNRPC: Fix a race in rpc_info_open
  SUNRPC: Fix race corrupting rpc upcall
  Fix null dereference in call_allocate
2010-09-14 17:04:48 -07:00
Eric Dumazet
ef885afbf8 net: use rcu_barrier() in rollback_registered_many
netdev_wait_allrefs() waits that all references to a device vanishes.

It currently uses a _very_ pessimistic 250 ms delay between each probe.
Some users reported that no more than 4 devices can be dismantled per
second, this is a pretty serious problem for some setups.

Most of the time, a refcount is about to be released by an RCU callback,
that is still in flight because rollback_registered_many() uses a
synchronize_rcu() call instead of rcu_barrier(). Problem is visible if
number of online cpus is one, because synchronize_rcu() is then a no op.

time to remove 50 ipip tunnels on a UP machine :

before patch : real 11.910s
after patch : real 1.250s

Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reported-by: Octavian Purdila <opurdila@ixiacom.com>
Reported-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 14:27:29 -07:00
Johannes Berg
a2c1e3dad5 mac80211: match only assigned bss in sta_info_get_bss
sta_info_get_bss() is used to match STA pointers
for VLAN/AP interfaces, but if the same station
is also added to multiple other interfaces it
will erroneously match because both pointers are
NULL, fix this by ignoring NULL pointers here.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:14:27 -04:00
Stanislaw Gruszka
edeb78a7fa mac80211: wait for scan work complete before restarting hw
This is needed to avoid warning in ieee80211_restart_hw about hardware
scan in progress.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi W Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:14:25 -04:00
Steve deRosier
740c1aa3b0 mac80211: Fix dangling pointer in ieee80211_xmit
hdr pointer is left dangling after call to ieee80211_skb_resize. This
can cause guards around mesh path selection to fail.

Signed-off-by: Steve deRosier <steve@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:08:03 -04:00
Bill Jordan
a1e567c83f nl80211: Uninitialized variable
There is a path in nl80211_set_wiphy where result is tested but
uninitialized.

I am hitting this path when I attempt:

sh# iw dev wlan0 set channel 10
command failed: Unknown error 1069727332 (-1069727332)

Signed-off-by: William Jordan <bjordan@rajant.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:08:03 -04:00
Nikitas Angelinas
942623166d net/wireless: use ARRAY_SIZE macro in radiotap.c
Replace sizeof(rtap_namespace_sizes) / sizeof(rtap_namespace_sizes[0])
with ARRAY_SIZE(rtap_namespace_sizes) in net/wireless/radiotap.c

Signed-off-by: Nikitas Angelinas <nikitasangelinas@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:05:57 -04:00
Eric Dumazet
83b6b1f5d1 flow: better memory management
Allocate hash tables for every online cpus, not every possible ones.

NUMA aware allocations.

Dont use a full page on arches where PAGE_SIZE > 1024*sizeof(void *)

misc:
  __percpu , __read_mostly, __cpuinit annotations
  flow_compare_t is just an "unsigned long"

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 20:02:50 -07:00
Michael Kerrisk
a89b47639f ipv4: enable getsockopt() for IP_NODEFRAG
While integrating your man-pages patch for IP_NODEFRAG, I noticed
that this option is settable by setsockopt(), but not gettable by
getsockopt(). I suppose this is not intended. The (untested,
trivial) patch below adds getsockopt() support.

Signed-off-by: Michael kerrisk <mtk.manpages@gmail.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 19:57:23 -07:00
Bob Arendt
7998156344 ipv4: force_igmp_version ignored when a IGMPv3 query received
After all these years, it turns out that the
    /proc/sys/net/ipv4/conf/*/force_igmp_version
parameter isn't fully implemented.

*Symptom*:
When set force_igmp_version to a value of 2, the kernel should only perform
multicast IGMPv2 operations (IETF rfc2236).  An host-initiated Join message
will be sent as a IGMPv2 Join message.  But if a IGMPv3 query message is
received, the host responds with a IGMPv3 join message.  Per rfc3376 and
rfc2236, a IGMPv2 host should treat a IGMPv3 query as a IGMPv2 query and
respond with an IGMPv2 Join message.

*Consequences*:
This is an issue when a IGMPv3 capable switch is the querier and will only
issue IGMPv3 queries (which double as IGMPv2 querys) and there's an
intermediate switch that is only IGMPv2 capable.  The intermediate switch
processes the initial v2 Join, but fails to recognize the IGMPv3 Join responses
to the Query, resulting in a dropped connection when the intermediate v2-only
switch times it out.

*Identifying issue in the kernel source*:
The issue is in this section of code (in net/ipv4/igmp.c), which is called when
an IGMP query is received  (from mainline 2.6.36-rc3 gitweb):
 ...
A IGMPv3 query has a length >= 12 and no sources.  This routine will exit after
line 880, setting the general query timer (random timeout between 0 and query
response time).  This calls igmp_gq_timer_expire():
...
.. which only sends a v3 response.  So if a v3 query is received, the kernel
always sends a v3 response.

IGMP queries happen once every 60 sec (per vlan), so the traffic is low.  A
IGMPv3 query *is* a strict superset of a IGMPv2 query, so this patch properly
short circuit's the v3 behaviour.

One issue is that this does not address force_igmp_version=1.  Then again, I've
never seen any IGMPv1 multicast equipment in the wild.  However there is a lot
of v2-only equipment. If it's necessary to support the IGMPv1 case as well:

837         if (len == 8 || IGMP_V2_SEEN(in_dev) || IGMP_V1_SEEN(in_dev)) {

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 12:56:51 -07:00
Dan Carpenter
339db11b21 net/llc: make opt unsigned in llc_ui_setsockopt()
The members of struct llc_sock are unsigned so if we pass a negative
value for "opt" it can cause a sign bug.  Also it can cause an integer
overflow when we multiply "opt * HZ".

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 12:44:10 -07:00
Latchesar Ionkov
62b2be591a fs/9p, net/9p: memory leak fixes
Four memory leak fixes in the 9P code.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
2010-09-13 08:13:02 -05:00
Miquel van Smoorenburg
db5fe26541 sunrpc: increase MAX_HASHTABLE_BITS to 14
The maximum size of the authcache is now set to 1024 (10 bits),
but on our server we need at least 4096 (12 bits). Increase
MAX_HASHTABLE_BITS to 14. This is a maximum of 16384 entries,
each containing a pointer (8 bytes on x86_64). This is
exactly the limit of kmalloc() (128K).

Signed-off-by: Miquel van Smoorenburg <mikevs@xs4all.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-12 19:55:26 -04:00
Bian Naimeng
651b2933b2 gss:spkm3 miss returning error to caller when import security context
spkm3 miss returning error to up layer when import security context,
it may be return ok though it has failed to import security context.

Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-12 19:55:26 -04:00
Bian Naimeng
ce8477e117 gss:krb5 miss returning error to caller when import security context
krb5 miss returning error to up layer when import security context,
it may be return ok though it has failed to import security context.

Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-12 19:55:25 -04:00
J. Bruce Fields
55576244eb SUNRPC: cleanup state-machine ordering
This is just a minor cleanup: net/sunrpc/clnt.c clarifies the rpc client
state machine by commenting each state and by laying out the functions
implementing each state in the order that each state is normally
executed (in the absence of errors).

The previous patch "Fix null dereference in call_allocate" changed the
order of the states.  Move the functions and update the comments to
reflect the change.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-09-12 19:55:25 -04:00
Trond Myklebust
006abe887c SUNRPC: Fix a race in rpc_info_open
There is a race between rpc_info_open and rpc_release_client()
in that nothing stops a process from opening the file after
the clnt->cl_kref goes to zero.

Fix this by using atomic_inc_unless_zero()...

Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-09-12 19:55:25 -04:00
Trond Myklebust
5a67657a2e SUNRPC: Fix race corrupting rpc upcall
If rpc_queue_upcall() adds a new upcall to the rpci->pipe list just
after rpc_pipe_release calls rpc_purge_list(), but before it calls
gss_pipe_release (as rpci->ops->release_pipe(inode)), then the latter
will free a message without deleting it from the rpci->pipe list.

We will be left with a freed object on the rpc->pipe list.  Most
frequent symptoms are kernel crashes in rpc.gssd system calls on the
pipe in question.

Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-09-12 19:55:25 -04:00
J. Bruce Fields
f2d47d02fd Fix null dereference in call_allocate
In call_allocate we need to reach the auth in order to factor au_cslack
into the allocation.

As of a17c2153d2 "SUNRPC: Move the bound
cred to struct rpc_rqst", call_allocate attempts to do this by
dereferencing tk_client->cl_auth, however this is not guaranteed to be
defined--cl_auth can be zero in the case of gss context destruction (see
rpc_free_auth).

Reorder the client state machine to bind credentials before allocating,
so that we can instead reach the auth through the cred.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-09-12 19:55:25 -04:00
David S. Miller
a505b3b30f sch_atm: Fix potential NULL deref.
The list_head conversion unearther an unnecessary flow
check.  Since flow is always NULL here we don't need to
see if a matching flow exists already.

Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-12 11:56:44 -07:00
stephen hemminger
9ca7f87622 pkt_sched: remov unnecessary bh_disable
Now that est_tree_lock is acquired with BH protection, the other
call is unnecessary.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-10 12:47:59 -07:00
Eric Dumazet
a034ee3cca fib: cleanups
Use rcu_dereference_rtnl() helper

Change hard coded constants in fib_flag_trans()
 7 -> RTN_UNREACHABLE
 8 -> RTN_PROHIBIT

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-10 12:32:02 -07:00
David S. Miller
e548833df8 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/mac80211/main.c
2010-09-09 22:27:33 -07:00
Paul Gortmaker
b2abd4c033 tipc: Optimize handling excess content on incoming messages
Remove code that trimmed excess trailing info from incoming messages
arriving over an Ethernet interface.  TIPC now ignores the extra info
while the message is being processed by the node, and only trims it off
if the message is retransmitted to another node.  (This latter step is
done to ensure the extra info doesn't cause the sk_buff to exceed the
outgoing interface's MTU limit.) The outgoing buffer is guaranteed to
be linear.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 21:34:14 -07:00
Eric Dumazet
49d61e2390 tunnels: missing rcu_assign_pointer()
xfrm4_tunnel_register() & xfrm6_tunnel_register() should
use rcu_assign_pointer() to make sure previous writes
(to handler->next) are committed to memory before chain
insertion.

deregister functions dont need a particular barrier.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:02:39 -07:00
Namhyung Kim
f39234d606 net/core: add lock context change annotations in net/core/sock.c
__lock_sock() and __release_sock() releases and regrabs lock but
were missing proper annotations. Add it. This removes following
warning from sparse. (Currently __lock_sock() does not emit any
warning about it but I think it is better to add also.)

 net/core/sock.c:1580:17: warning: context imbalance in '__release_sock' - unexpected unlock

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:02:39 -07:00
Namhyung Kim
a700d8be73 net/core: remove address space warnings on verify_iovec()
move_addr_to_kernel() and copy_from_user() requires their argument
as __user pointer but were missing proper markups. Add it.
This removes following warnings from sparse.

 net/core/iovec.c:44:52: warning: incorrect type in argument 1 (different address spaces)
 net/core/iovec.c:44:52:    expected void [noderef] <asn:1>*uaddr
 net/core/iovec.c:44:52:    got void *msg_name
 net/core/iovec.c:55:34: warning: incorrect type in argument 2 (different address spaces)
 net/core/iovec.c:55:34:    expected void const [noderef] <asn:1>*from
 net/core/iovec.c:55:34:    got struct iovec *msg_iov

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:02:38 -07:00
Joe Perches
123031c0ee sctp: fix test for end of loop
Add a list_has_sctp_addr function to simplify loop

Based on a patches by Dan Carpenter and David Miller

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:00:29 -07:00
David S. Miller
cf0ac2b8a7 Merge branch 'for-davem' of git://oss.oracle.com/git/agrover/linux-2.6 2010-09-09 14:58:11 -07:00
David S. Miller
e199e6136c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 2010-09-08 23:49:04 -07:00
Eric Dumazet
719f835853 udp: add rehash on connect()
commit 30fff923 introduced in linux-2.6.33 (udp: bind() optimisation)
added a secondary hash on UDP, hashed on (local addr, local port).

Problem is that following sequence :

fd = socket(...)
connect(fd, &remote, ...)

not only selects remote end point (address and port), but also sets
local address, while UDP stack stored in secondary hash table the socket
while its local address was INADDR_ANY (or ipv6 equivalent)

Sequence is :
 - autobind() : choose a random local port, insert socket in hash tables
              [while local address is INADDR_ANY]
 - connect() : set remote address and port, change local address to IP
              given by a route lookup.

When an incoming UDP frame comes, if more than 10 sockets are found in
primary hash table, we switch to secondary table, and fail to find
socket because its local address changed.

One solution to this problem is to rehash datagram socket if needed.

We add a new rehash(struct socket *) method in "struct proto", and
implement this method for UDP v4 & v6, using a common helper.

This rehashing only takes care of secondary hash table, since primary
hash (based on local port only) is not changed.

Reported-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-08 21:45:01 -07:00
Eric Dumazet
e0386005ff net: inet_add_protocol() can use cmpxchg()
Use cmpxchg() to get rid of spinlocks in inet_add_protocol() and
friends.

inet_protos[] & inet6_protos[] are moved to read_mostly section

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-08 21:31:35 -07:00
Andy Grover
20c72bd5f5 RDS: Implement masked atomic operations
Add two CMSGs for masked versions of cswp and fadd. args
struct modified to use a union for different atomic op type's
arguments. Change IB to do masked atomic ops. Atomic op type
in rds_message similarly unionized.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:16:51 -07:00
Zach Brown
59f740a6ae RDS/IB: print string constants in more places
This prints the constant identifier for work completion status and rdma
cm event types, like we already do for IB event types.

A core string array helper is added that each string type uses.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:50 -07:00
Zach Brown
4518071ac1 RDS: cancel connection work structs as we shut down
Nothing was canceling the send and receive work that might have been
queued as a conn was being destroyed.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:49 -07:00
Zach Brown
ffcec0e110 RDS: don't call rds_conn_shutdown() from rds_conn_destroy()
rds_conn_shutdown() can return before the connection is shut down when
it encounters an existing state that it doesn't understand.  This lets
rds_conn_destroy() then start tearing down the conn from under paths
that are still using it.

It's more reliable the shutdown work and wait for krdsd to complete the
shutdown callback.  This stopped some hangs I was seeing where krdsd was
trying to shut down a freed conn.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:48 -07:00
Zach Brown
5adb5bc65f RDS: have sockets get transport module references
Right now there's nothing to stop the various paths that use
rs->rs_transport from racing with rmmod and executing freed transport
code.  The simple fix is to have binding to a transport also hold a
reference to the transport's module, removing this class of races.

We already had an unused t_owner field which was set for the modular
transports and which wasn't set for the built-in loop transport.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:47 -07:00
Zach Brown
77510481c0 RDS: remove old rs_transport comment
rs_transport is now also used by the rdma paths once the socket is
bound.  We don't need this stale comment to tell us what cscope can.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:46 -07:00
Zach Brown
fe8ff6b58f RDS: lock rds_conn_count decrement in rds_conn_destroy()
rds_conn_destroy() can race with all other modifications of the
rds_conn_count but it was modifying the count without locking.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:45 -07:00
Zach Brown
ea819867b7 RDS/IB: protect the list of IB devices
The RDS IB device list wasn't protected by any locking.  Traversal in
both the get_mr and FMR flushing paths could race with additon and
removal.

List manipulation is done with RCU primatives and is protected by the
write side of a rwsem.  The list traversal in the get_mr fast path is
protected by a rcu read critical section.  The FMR list traversal is
more problematic because it can block while traversing the list.  We
protect this with the read side of the rwsem.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:44 -07:00
Zach Brown
1bde04a63d RDS/IB: print IB event strings as well as their number
It's nice to not have to go digging in the code to see which event
occurred.  It's easy to throw together a quick array that maps the ib
event enums to their strings.  I didn't see anything in the stack that
does this translation for us, but I also didn't look very hard.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:43 -07:00
Chris Mason
8576f374ac RDS: flush fmrs before allocating new ones
Flushing FMRs is somewhat expensive, and is currently kicked off when
the interrupt handler notices that we are getting low.  The result of
this is that FMR flushing only happens from the interrupt cpus.

This spreads the load more effectively by triggering flushes just before
we allocate a new FMR.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:16:42 -07:00
Chris Mason
b4e1da3c9a RDS: properly use sg_init_table
This is only needed to keep debugging code from bugging.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:16:41 -07:00
Zach Brown
f046011cd7 RDS/IB: track signaled sends
We're seeing bugs today where IB connection shutdown clears the send
ring while the tasklet is processing completed sends.  Implementation
details cause this to dereference a null pointer.  Shutdown needs to
wait for send completion to stop before tearing down the connection.  We
can't simply wait for the ring to empty because it may contain
unsignaled sends that will never be processed.

This patch tracks the number of signaled sends that we've posted and
waits for them to complete.  It also makes sure that the tasklet has
finished executing.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:40 -07:00
Zach Brown
ef87b7ea39 RDS: remove __init and __exit annotation
The trivial amount of memory saved isn't worth the cost of dealing with section
mismatches.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:39 -07:00
Andy Grover
c20f5b9633 RDS/IB: Use SLAB_HWCACHE_ALIGN flag for kmem_cache_create()
We are *definitely* counting cycles as closely as DaveM, so
ensure hwcache alignment for our recv ring control structs.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:16:38 -07:00
Zach Brown
d455ab6409 RDS/IB: always process recv completions
The recv refill path was leaking fragments because the recv event handler had
marked a ring element as free without freeing its frag.  This was happening
because it wasn't processing receives when the conn wasn't marked up or
connecting, as can be the case if it races with rmmod.

Two observations support always processing receives in the callback.

First, buildup should only post receives, thus triggering recv event handler
calls, once it has built up all the state to handle them.  Teardown should
destroy the CQ and drain the ring before tearing down the state needed to
process recvs.  Both appear to be true today.

Second, this test was fundamentally racy.  There is nothing to stop rmmod and
connection destruction from swooping in the moment after the conn state was
sampled but before real receive procesing starts.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:36 -07:00
Zach Brown
80c51be56f RDS: return to a single-threaded krdsd
We were seeing very nasty bugs due to fundamental assumption the current code
makes about concurrent work struct processing.  The code simpy isn't able to
handle concurrent connection shutdown work function execution today, for
example, which is very much possible once a multi-threaded krdsd was
introduced.  The problem compounds as additional work structs are added to the
mix.

krdsd is no longer perforance critical now that send and receive posting and
FMR flushing are done elsewhere, so the safest fix is to move back to the
single threaded krdsd that the current code was built around.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:35 -07:00
Zach Brown
515e079dab RDS/IB: create a work queue for FMR flushing
This patch moves the FMR flushing work in to its own mult-threaded work queue.
This is to maintain performance in preparation for returning the main krdsd
work queue back to a single threaded work queue to avoid deep-rooted
concurrency bugs.

This is also good because it further separates FMRs, which might be removed
some day, from the rest of the code base.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:34 -07:00