Skip to content

R
raspberrypi-kernel

openeuler / raspberrypi-kernel

通知 13
Star 1
Fork 0
R
raspberrypi-kernel
切换分支/标签
  1. 11 6月, 2015 1 次提交
  3. 23 4月, 2015 1 次提交
  5. 25 3月, 2015 2 次提交
  7. 24 3月, 2015 1 次提交
  9. 21 3月, 2015 1 次提交
  11. 20 3月, 2015 2 次提交
  13. 19 3月, 2015 1 次提交
  15. 18 3月, 2015 1 次提交
    • Y
      tipc: fix netns refcnt leak · 76100a8a
      由 Ying Xue 提交于 
      When the TIPC module is loaded, we launch a topology server in kernel
space, which in its turn is creating TIPC sockets for communication
with topology server users. Because both the socket's creator and
provider reside in the same module, it is necessary that the TIPC
module's reference count remains zero after the server is started and
the socket created; otherwise it becomes impossible to perform "rmmod"
even on an idle module.

Currently, we achieve this by defining a separate "tipc_proto_kern"
protocol struct, that is used only for kernel space socket allocations.
This structure has the "owner" field set to NULL, which restricts the
module reference count from being be bumped when sk_alloc() for local
sockets is called. Furthermore, we have defined three kernel-specific
functions, tipc_sock_create_local(), tipc_sock_release_local() and
tipc_sock_accept_local(), to avoid the module counter being modified
when module local sockets are created or deleted. This has worked well
until we introduced name space support.

However, after name space support was introduced, we have observed that
a reference count leak occurs, because the netns counter is not
decremented in tipc_sock_delete_local().

This commit remedies this problem. But instead of just modifying
tipc_sock_delete_local(), we eliminate the whole parallel socket
handling infrastructure, and start using the regular sk_create_kern(),
kernel_accept() and sk_release_kernel() calls. Since those functions
manipulate the module counter, we must now compensate for that by
explicitly decrementing the counter after module local sockets are
created, and increment it just before calling sk_release_kernel().

Fixes: a62fbcce ("tipc: make subscriber server support net namespace")
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Reviewed-by: NJon Maloy <jon.maloy@ericson.com>
Reviewed-by: NErik Hugne <erik.hugne@ericsson.com>
Reported-by: NCong Wang <cwang@twopensource.com>
Tested-by: NErik Hugne <erik.hugne@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      76100a8a
  17. 10 3月, 2015 1 次提交
  19. 03 3月, 2015 2 次提交
  21. 28 2月, 2015 1 次提交
  23. 10 2月, 2015 3 次提交
  25. 09 2月, 2015 1 次提交
  27. 06 2月, 2015 8 次提交
    • J
      tipc: eliminate race condition at multicast reception · cb1b7280
      由 Jon Paul Maloy 提交于 
      In a previous commit in this series we resolved a race problem during
unicast message reception.

Here, we resolve the same problem at multicast reception. We apply the
same technique: an input queue serializing the delivery of arriving
buffers. The main difference is that here we do it in two steps.
First, the broadcast link feeds arriving buffers into the tail of an
arrival queue, which head is consumed at the socket level, and where
destination lookup is performed. Second, if the lookup is successful,
the resulting buffer clones are fed into a second queue, the input
queue. This queue is consumed at reception in the socket just like
in the unicast case. Both queues are protected by the same lock, -the
one of the input queue.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cb1b7280
    • J
      tipc: simplify socket multicast reception · 3c724acd
      由 Jon Paul Maloy 提交于 
      The structure 'tipc_port_list' is used to collect port numbers
representing multicast destination socket on a receiving node.
The list is not based on a standard linked list, and is in reality
optimized for the uncommon case that there are more than one
multicast destinations per node. This makes the list handling
unecessarily complex, and as a consequence, even the socket
multicast reception becomes more complex.

In this commit, we replace 'tipc_port_list' with a new 'struct
tipc_plist', which is based on a standard list. We give the new
list stack (push/pop) semantics, someting that simplifies
the implementation of the function tipc_sk_mcast_rcv().
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3c724acd
    • J
      tipc: resolve race problem at unicast message reception · c637c103
      由 Jon Paul Maloy 提交于 
      TIPC handles message cardinality and sequencing at the link layer,
before passing messages upwards to the destination sockets. During the
upcall from link to socket no locks are held. It is therefore possible,
and we see it happen occasionally, that messages arriving in different
threads and delivered in sequence still bypass each other before they
reach the destination socket. This must not happen, since it violates
the sequentiality guarantee.

We solve this by adding a new input buffer queue to the link structure.
Arriving messages are added safely to the tail of that queue by the
link, while the head of the queue is consumed, also safely, by the
receiving socket. Sequentiality is secured per socket by only allowing
buffers to be dequeued inside the socket lock. Since there may be multiple
simultaneous readers of the queue, we use a 'filter' parameter to reduce
the risk that they peek the same buffer from the queue, hence also
reducing the risk of contention on the receiving socket locks.

This solves the sequentiality problem, and seems to cause no measurable
performance degradation.

A nice side effect of this change is that lock handling in the functions
tipc_rcv() and tipc_bcast_rcv() now becomes uniform, something that
will enable future simplifications of those functions.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c637c103
    • J
      tipc: use existing sk_write_queue for outgoing packet chain · 94153e36
      由 Jon Paul Maloy 提交于 
      The list for outgoing traffic buffers from a socket is currently
allocated on the stack. This forces us to initialize the queue for
each sent message, something costing extra CPU cycles in the most
critical data path. Later in this series we will introduce a new
safe input buffer queue, something that would force us to initialize
even the spinlock of the outgoing queue. A closer analysis reveals
that the queue always is filled and emptied within the same lock_sock()
session. It is therefore safe to use a queue aggregated in the socket
itself for this purpose. Since there already exists a queue for this
in struct sock, sk_write_queue, we introduce use of that queue in
this commit.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      94153e36
    • J
      tipc: split up function tipc_msg_eval() · e3a77561
      由 Jon Paul Maloy 提交于 
      The function tipc_msg_eval() is in reality doing two related, but
different tasks. First it tries to find a new destination for named
messages, in case there was no first lookup, or if the first lookup
failed. Second, it does what its name suggests, evaluating the validity
of the message and its destination, and returning an appropriate error
code depending on the result.

This is confusing, and in this commit we choose to break it up into two
functions. A new function, tipc_msg_lookup_dest(), first attempts to find
a new destination, if the message is of the right type. If this lookup
fails, or if the message should not be subject to a second lookup, the
already existing tipc_msg_reverse() is called. This function performs
prepares the message for rejection, if applicable.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e3a77561
    • J
      tipc: enqueue arrived buffers in socket in separate function · d570d864
      由 Jon Paul Maloy 提交于 
      The code for enqueuing arriving buffers in the function tipc_sk_rcv()
contains long code lines and currently goes to two indentation levels.
As a cosmetic preparaton for the next commits, we break it out into
a separate function.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d570d864
    • J
      tipc: simplify message forwarding and rejection in socket layer · 1186adf7
      由 Jon Paul Maloy 提交于 
      Despite recent improvements, the handling of error codes and return
values at reception of messages in the socket layer is still confusing.

In this commit, we try to make it more comprehensible. First, we
separate between the return values coming from the functions called
by tipc_sk_rcv(), -those are TIPC specific error codes, and the
return values returned by tipc_sk_rcv() itself. Second, we don't
use the returned TIPC error code as indication for whether a buffer
should be forwarded/rejected or not; instead we use the buffer pointer
passed along with filter_msg(). This separation is necessary because
we sometimes want to forward messages even when there is no error
(i.e., protocol messages and successfully secondary looked up data
messages).
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1186adf7
    • J
      tipc: reduce usage of context info in socket and link · c5898636
      由 Jon Paul Maloy 提交于 
      The most common usage of namespace information is when we fetch the
own node addess from the net structure. This leads to a lot of
passing around of a parameter of type 'struct net *' between
functions just to make them able to obtain this address.

However, in many cases this is unnecessary. The own node address
is readily available as a member of both struct tipc_sock and
tipc_link, and can be fetched from there instead.
The fact that the vast majority of functions in socket.c and link.c
anyway are maintaining a pointer to their respective base structures
makes this option even more compelling.

In this commit, we introduce the inline functions tsk_own_node()
and link_own_node() to make it easy for functions to fetch the node
address from those structs instead of having to pass along and
dereference the namespace struct.

In particular, we make calls to the msg_xx() functions in msg.{h,c}
context independent by directly passing them the own node address
as parameter when needed. Those functions should be regarded as
leaves in the code dependency tree, and it is hence desirable to
keep them namspace unaware.

Apart from a potential positive effect on cache behavior, these
changes make it easier to introduce the changes that will follow
later in this series.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c5898636
  29. 04 2月, 2015 1 次提交
  31. 18 1月, 2015 1 次提交
  33. 14 1月, 2015 2 次提交
  35. 13 1月, 2015 7 次提交
  37. 09 1月, 2015 1 次提交
    • Y
      tipc: convert tipc reference table to use generic rhashtable · 07f6c4bc
      由 Ying Xue 提交于 
      As tipc reference table is statically allocated, its memory size
requested on stack initialization stage is quite big even if the
maximum port number is just restricted to 8191 currently, however,
the number already becomes insufficient in practice. But if the
maximum ports is allowed to its theory value - 2^32, its consumed
memory size will reach a ridiculously unacceptable value. Apart from
this, heavy tipc users spend a considerable amount of time in
tipc_sk_get() due to the read-lock on ref_table_lock.

If tipc reference table is converted with generic rhashtable, above
mentioned both disadvantages would be resolved respectively: making
use of the new resizable hash table can avoid locking on the lookup;
smaller memory size is required at initial stage, for example, 256
hash bucket slots are requested at the beginning phase instead of
allocating the entire 8191 slots in old mode. The hash table will
grow if entries exceeds 75% of table size up to a total table size
of 1M, and it will automatically shrink if usage falls below 30%,
but the minimum table size is allowed down to 256.

Also converts ref_table_lock to a separate mutex to protect hash table
mutations on write side. Lastly defers the release of the socket
reference using call_rcu() to allow using an RCU read-side protected
call to rhashtable_lookup().
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NErik Hugne <erik.hugne@ericsson.com>
Cc: Thomas Graf <tgraf@suug.ch>
Acked-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      07f6c4bc
  39. 10 12月, 2014 1 次提交
  41. 27 11月, 2014 1 次提交