1. 29 4月, 2009 2 次提交
    • M
      Bluetooth: Add different pairing timeout for Legacy Pairing · 052b30b0
      Marcel Holtmann 提交于
      The Bluetooth stack uses a reference counting for all established ACL
      links and if no user (L2CAP connection) is present, the link will be
      terminated to save power. The problem part is the dedicated pairing
      when using Legacy Pairing (Bluetooth 2.0 and before). At that point
      no user is present and pairing attempts will be disconnected within
      10 seconds or less. In previous kernel version this was not a problem
      since the disconnect timeout wasn't triggered on incoming connections
      for the first time. However this caused issues with broken host stacks
      that kept the connections around after dedicated pairing. When the
      support for Simple Pairing got added, the link establishment procedure
      needed to be changed and now causes issues when using Legacy Pairing
      
      When using Simple Pairing it is possible to do a proper reference
      counting of ACL link users. With Legacy Pairing this is not possible
      since the specification is unclear in some areas and too many broken
      Bluetooth devices have already been deployed. So instead of trying to
      deal with all the broken devices, a special pairing timeout will be
      introduced that increases the timeout to 60 seconds when pairing is
      triggered.
      
      If a broken devices now puts the stack into an unforeseen state, the
      worst that happens is the disconnect timeout triggers after 120 seconds
      instead of 4 seconds. This allows successful pairings with legacy and
      broken devices now.
      
      Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
      Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
      052b30b0
    • R
      Bluetooth: Ensure that HCI sysfs add/del is preempt safe · f3784d83
      Roger Quadros 提交于
      Use a different work_struct variables for add_conn() and del_conn() and
      use single work queue instead of two for adding and deleting connections.
      
      It eliminates the following error on a preemptible kernel:
      
      [  204.358032] Unable to handle kernel NULL pointer dereference at virtual address 0000000c
      [  204.370697] pgd = c0004000
      [  204.373443] [0000000c] *pgd=00000000
      [  204.378601] Internal error: Oops: 17 [#1] PREEMPT
      [  204.383361] Modules linked in: vfat fat rfcomm sco l2cap sd_mod scsi_mod iphb pvr2d drm omaplfb ps
      [  204.438537] CPU: 0    Not tainted  (2.6.28-maemo2 #1)
      [  204.443664] PC is at klist_put+0x2c/0xb4
      [  204.447601] LR is at klist_put+0x18/0xb4
      [  204.451568] pc : [<c0270f08>]    lr : [<c0270ef4>]    psr: a0000113
      [  204.451568] sp : cf1b3f10  ip : cf1b3f10  fp : cf1b3f2c
      [  204.463104] r10: 00000000  r9 : 00000000  r8 : bf08029c
      [  204.468353] r7 : c7869200  r6 : cfbe2690  r5 : c78692c8  r4 : 00000001
      [  204.474945] r3 : 00000001  r2 : cf1b2000  r1 : 00000001  r0 : 00000000
      [  204.481506] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM Segment kernel
      [  204.488861] Control: 10c5387d  Table: 887fc018  DAC: 00000017
      [  204.494628] Process btdelconn (pid: 515, stack limit = 0xcf1b22e0)
      Signed-off-by: NRoger Quadros <ext-roger.quadros@nokia.com>
      Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
      f3784d83
  2. 28 4月, 2009 1 次提交
    • E
      net: Avoid extra wakeups of threads blocked in wait_for_packet() · bf368e4e
      Eric Dumazet 提交于
      In 2.6.25 we added UDP mem accounting.
      
      This unfortunatly added a penalty when a frame is transmitted, since
      we have at TX completion time to call sock_wfree() to perform necessary
      memory accounting. This calls sock_def_write_space() and utimately
      scheduler if any thread is waiting on the socket.
      Thread(s) waiting for an incoming frame was scheduled, then had to sleep
      again as event was meaningless.
      
      (All threads waiting on a socket are using same sk_sleep anchor)
      
      This adds lot of extra wakeups and increases latencies, as noted
      by Christoph Lameter, and slows down softirq handler.
      
      Reference : http://marc.info/?l=linux-netdev&m=124060437012283&w=2 
      
      Fortunatly, Davide Libenzi recently added concept of keyed wakeups
      into kernel, and particularly for sockets (see commit
      37e5540b 
      epoll keyed wakeups: make sockets use keyed wakeups)
      
      Davide goal was to optimize epoll, but this new wakeup infrastructure
      can help non epoll users as well, if they care to setup an appropriate
      handler.
      
      This patch introduces new DEFINE_WAIT_FUNC() helper and uses it
      in wait_for_packet(), so that only relevant event can wakeup a thread
      blocked in this function.
      
      Trace of function calls from bnx2 TX completion bnx2_poll_work() is :
      __kfree_skb()
       skb_release_head_state()
        sock_wfree()
         sock_def_write_space()
          __wake_up_sync_key()
           __wake_up_common()
            receiver_wake_function() : Stops here since thread is waiting for an INPUT
      Reported-by: NChristoph Lameter <cl@linux.com>
      Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bf368e4e
  3. 27 4月, 2009 12 次提交
  4. 26 4月, 2009 2 次提交
  5. 24 4月, 2009 4 次提交
  6. 22 4月, 2009 17 次提交
  7. 21 4月, 2009 2 次提交