1. 09 9月, 2010 1 次提交
    • J
      ipv4: Suppress lockdep-RCU false positive in FIB trie (3) · f6b085b6
      Jarek Poplawski 提交于
      Hi,
      Here is one more of these warnings and a patch below:
      
      Sep  5 23:52:33 del kernel: [46044.244833] ===================================================
      Sep  5 23:52:33 del kernel: [46044.269681] [ INFO: suspicious rcu_dereference_check() usage. ]
      Sep  5 23:52:33 del kernel: [46044.277000] ---------------------------------------------------
      Sep  5 23:52:33 del kernel: [46044.285185] net/ipv4/fib_trie.c:1756 invoked rcu_dereference_check() without protection!
      Sep  5 23:52:33 del kernel: [46044.293627]
      Sep  5 23:52:33 del kernel: [46044.293632] other info that might help us debug this:
      Sep  5 23:52:33 del kernel: [46044.293634]
      Sep  5 23:52:33 del kernel: [46044.325333]
      Sep  5 23:52:33 del kernel: [46044.325335] rcu_scheduler_active = 1, debug_locks = 0
      Sep  5 23:52:33 del kernel: [46044.348013] 1 lock held by pppd/1717:
      Sep  5 23:52:33 del kernel: [46044.357548]  #0:  (rtnl_mutex){+.+.+.}, at: [<c125dc1f>] rtnl_lock+0xf/0x20
      Sep  5 23:52:33 del kernel: [46044.367647]
      Sep  5 23:52:33 del kernel: [46044.367652] stack backtrace:
      Sep  5 23:52:33 del kernel: [46044.387429] Pid: 1717, comm: pppd Not tainted 2.6.35.4.4a #3
      Sep  5 23:52:33 del kernel: [46044.398764] Call Trace:
      Sep  5 23:52:33 del kernel: [46044.409596]  [<c12f9aba>] ? printk+0x18/0x1e
      Sep  5 23:52:33 del kernel: [46044.420761]  [<c1053969>] lockdep_rcu_dereference+0xa9/0xb0
      Sep  5 23:52:33 del kernel: [46044.432229]  [<c12b7235>] trie_firstleaf+0x65/0x70
      Sep  5 23:52:33 del kernel: [46044.443941]  [<c12b74d4>] fib_table_flush+0x14/0x170
      Sep  5 23:52:33 del kernel: [46044.455823]  [<c1033e92>] ? local_bh_enable_ip+0x62/0xd0
      Sep  5 23:52:33 del kernel: [46044.467995]  [<c12fc39f>] ? _raw_spin_unlock_bh+0x2f/0x40
      Sep  5 23:52:33 del kernel: [46044.480404]  [<c12b24d0>] ? fib_sync_down_dev+0x120/0x180
      Sep  5 23:52:33 del kernel: [46044.493025]  [<c12b069d>] fib_flush+0x2d/0x60
      Sep  5 23:52:33 del kernel: [46044.505796]  [<c12b06f5>] fib_disable_ip+0x25/0x50
      Sep  5 23:52:33 del kernel: [46044.518772]  [<c12b10d3>] fib_netdev_event+0x73/0xd0
      Sep  5 23:52:33 del kernel: [46044.531918]  [<c1048dfd>] notifier_call_chain+0x2d/0x70
      Sep  5 23:52:33 del kernel: [46044.545358]  [<c1048f0a>] raw_notifier_call_chain+0x1a/0x20
      Sep  5 23:52:33 del kernel: [46044.559092]  [<c124f687>] call_netdevice_notifiers+0x27/0x60
      Sep  5 23:52:33 del kernel: [46044.573037]  [<c124faec>] __dev_notify_flags+0x5c/0x80
      Sep  5 23:52:33 del kernel: [46044.586489]  [<c124fb47>] dev_change_flags+0x37/0x60
      Sep  5 23:52:33 del kernel: [46044.599394]  [<c12a8a8d>] devinet_ioctl+0x54d/0x630
      Sep  5 23:52:33 del kernel: [46044.612277]  [<c12aabb7>] inet_ioctl+0x97/0xc0
      Sep  5 23:52:34 del kernel: [46044.625208]  [<c123f6af>] sock_ioctl+0x6f/0x270
      Sep  5 23:52:34 del kernel: [46044.638046]  [<c109d2b0>] ? handle_mm_fault+0x420/0x6c0
      Sep  5 23:52:34 del kernel: [46044.650968]  [<c123f640>] ? sock_ioctl+0x0/0x270
      Sep  5 23:52:34 del kernel: [46044.663865]  [<c10c3188>] vfs_ioctl+0x28/0xa0
      Sep  5 23:52:34 del kernel: [46044.676556]  [<c10c38fa>] do_vfs_ioctl+0x6a/0x5c0
      Sep  5 23:52:34 del kernel: [46044.688989]  [<c1048676>] ? up_read+0x16/0x30
      Sep  5 23:52:34 del kernel: [46044.701411]  [<c1021376>] ? do_page_fault+0x1d6/0x3a0
      Sep  5 23:52:34 del kernel: [46044.714223]  [<c10b6588>] ? fget_light+0xf8/0x2f0
      Sep  5 23:52:34 del kernel: [46044.726601]  [<c1241f98>] ? sys_socketcall+0x208/0x2c0
      Sep  5 23:52:34 del kernel: [46044.739140]  [<c10c3eb3>] sys_ioctl+0x63/0x70
      Sep  5 23:52:34 del kernel: [46044.751967]  [<c12fca3d>] syscall_call+0x7/0xb
      Sep  5 23:52:34 del kernel: [46044.764734]  [<c12f0000>] ? cookie_v6_check+0x3d0/0x630
      
      -------------->
      
      This patch fixes the warning:
       ===================================================
       [ INFO: suspicious rcu_dereference_check() usage. ]
       ---------------------------------------------------
       net/ipv4/fib_trie.c:1756 invoked rcu_dereference_check() without protection!
      
       other info that might help us debug this:
      
       rcu_scheduler_active = 1, debug_locks = 0
       1 lock held by pppd/1717:
        #0:  (rtnl_mutex){+.+.+.}, at: [<c125dc1f>] rtnl_lock+0xf/0x20
      
       stack backtrace:
       Pid: 1717, comm: pppd Not tainted 2.6.35.4a #3
       Call Trace:
        [<c12f9aba>] ? printk+0x18/0x1e
        [<c1053969>] lockdep_rcu_dereference+0xa9/0xb0
        [<c12b7235>] trie_firstleaf+0x65/0x70
        [<c12b74d4>] fib_table_flush+0x14/0x170
        ...
      
      Allow trie_firstleaf() to be called either under rcu_read_lock()
      protection or with RTNL held. The same annotation is added to
      node_parent_rcu() to prevent a similar warning a bit later.
      
      Followup of commits 634a4b20 and 4eaa0e3c.
      Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f6b085b6
  2. 18 5月, 2010 1 次提交
  3. 15 4月, 2010 1 次提交
  4. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  5. 22 3月, 2010 1 次提交
  6. 05 10月, 2009 1 次提交
  7. 29 8月, 2009 1 次提交
    • J
      fib_trie: resize rework · 80b71b80
      Jens Låås 提交于
      Here is rework and cleanup of the resize function.
      
      Some bugs we had. We were using ->parent when we should use 
      node_parent(). Also we used ->parent which is not assigned by
      inflate in inflate loop.
      
      Also a fix to set thresholds to power 2 to fit halve 
      and double strategy.
      
      max_resize is renamed to max_work which better indicates
      it's function.
      
      Reaching max_work is not an error, so warning is removed. 
      max_work only limits amount of work done per resize.
      (limits CPU-usage, outstanding memory etc).
      
      The clean-up makes it relatively easy to add fixed sized 
      root-nodes if we would like to decrease the memory pressure
      on routers with large routing tables and dynamic routing.
      If we'll need that...
      
      Its been tested with 280k routes.
      
      Work done together with Robert Olsson.
      Signed-off-by: NJens Låås <jens.laas@its.uu.se>
      Signed-off-by: NRobert Olsson <robert.olsson@its.uu.se>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      80b71b80
  8. 06 8月, 2009 1 次提交
  9. 20 7月, 2009 3 次提交
  10. 09 7月, 2009 1 次提交
    • J
      ipv4: Fix fib_trie rebalancing, part 4 (root thresholds) · 345aa031
      Jarek Poplawski 提交于
      Pawel Staszewski wrote:
      <blockquote>
      Some time ago i report this:
      http://bugzilla.kernel.org/show_bug.cgi?id=6648
      
      and now with 2.6.29 / 2.6.29.1 / 2.6.29.3 and 2.6.30 it back
      dmesg output:
      oprofile: using NMI interrupt.
      Fix inflate_threshold_root. Now=15 size=11 bits
      ...
      Fix inflate_threshold_root. Now=15 size=11 bits
      
      cat /proc/net/fib_triestat
      Basic info: size of leaf: 40 bytes, size of tnode: 56 bytes.
      Main:
              Aver depth:     2.28
              Max depth:      6
              Leaves:         276539
              Prefixes:       289922
              Internal nodes: 66762
                1: 35046  2: 13824  3: 9508  4: 4897  5: 2331  6: 1149  7: 5
      9: 1  18: 1
              Pointers: 691228
      Null ptrs: 347928
      Total size: 35709  kB
      </blockquote>
      
      It seems, the current threshold for root resizing is too aggressive,
      and it causes misleading warnings during big updates, but it might be
      also responsible for memory problems, especially with non-preempt
      configs, when RCU freeing is delayed long after call_rcu.
      
      It should be also mentioned that because of non-atomic changes during
      resizing/rebalancing the current lookup algorithm can miss valid leaves
      so it's additional argument to shorten these activities even at a cost
      of a minimally longer searching.
      
      This patch restores values before the patch "[IPV4]: fib_trie root
      node settings", commit: 965ffea4 from
      v2.6.22.
      
      Pawel's report:
      <blockquote>
      I dont see any big change of (cpu load or faster/slower
      routing/propagating routes from bgpd or something else) - in avg there
      is from 2% to 3% more of CPU load i dont know why but it is - i change
      from "preempt" to "no preempt" 3 times and check this my "mpstat -P ALL
      1 30"
      always avg cpu load was from 2 to 3% more compared to "no preempt"
      [...]
      cat /proc/net/fib_triestat
      Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes.
      Main:
              Aver depth:     2.44
              Max depth:      6
              Leaves:         277814
              Prefixes:       291306
              Internal nodes: 66420
                1: 32737  2: 14850  3: 10332  4: 4871  5: 2313  6: 942  7: 371  8: 3  17: 1
              Pointers: 599098
      Null ptrs: 254865
      Total size: 18067  kB
      </blockquote>
      
      According to this and other similar reports average depth is slightly
      increased (~0.2), and root nodes are shorter (log 17 vs. 18), but
      there is no visible performance decrease. So, until memory handling is
      improved or added parameters for changing this individually, this
      patch resets to safer defaults.
      Reported-by: NPawel Staszewski <pstaszewski@itcare.pl>
      Reported-by: NJorge Boncompte [DTI2] <jorge@dti2.net>
      Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
      Tested-by: NPawel Staszewski <pstaszewski@itcare.pl>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      345aa031
  11. 01 7月, 2009 1 次提交
  12. 18 6月, 2009 1 次提交
    • J
      ipv4: Fix fib_trie rebalancing, part 2 · 7b85576d
      Jarek Poplawski 提交于
      My previous patch, which explicitly delays freeing of tnodes by adding
      them to the list to flush them after the update is finished, isn't
      strict enough. It treats exceptionally tnodes without parent, assuming
      they are newly created, so "invisible" for the read side yet.
      
      But the top tnode doesn't have parent as well, so we have to exclude
      all exceptions (at least until a better way is found). Additionally we
      need to move rcu assignment of this node before flushing, so the
      return type of the trie_rebalance() function is changed.
      Reported-by: NYan Zheng <zheng.yan@oracle.com>
      Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      7b85576d
  13. 15 6月, 2009 1 次提交
    • J
      ipv4: Fix fib_trie rebalancing · e0f7cb8c
      Jarek Poplawski 提交于
      While doing trie_rebalance(): resize(), inflate(), halve() RCU free
      tnodes before updating their parents. It depends on RCU delaying the
      real destruction, but if RCU readers start after call_rcu() and before
      parent update they could access freed memory.
      
      It is currently prevented with preempt_disable() on the update side,
      but it's not safe, except maybe classic RCU, plus it conflicts with
      memory allocations with GFP_KERNEL flag used from these functions.
      
      This patch explicitly delays freeing of tnodes by adding them to the
      list, which is flushed after the update is finished.
      Reported-by: NYan Zheng <zheng.yan@oracle.com>
      Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e0f7cb8c
  14. 22 5月, 2009 1 次提交
  15. 19 5月, 2009 1 次提交
  16. 31 10月, 2008 1 次提交
  17. 18 7月, 2008 2 次提交
  18. 11 7月, 2008 1 次提交
  19. 06 7月, 2008 1 次提交
  20. 12 6月, 2008 1 次提交
  21. 24 4月, 2008 1 次提交
  22. 14 4月, 2008 1 次提交
  23. 10 4月, 2008 3 次提交
  24. 26 3月, 2008 1 次提交
  25. 24 3月, 2008 1 次提交
  26. 23 3月, 2008 1 次提交
  27. 13 2月, 2008 2 次提交
  28. 05 2月, 2008 1 次提交
  29. 01 2月, 2008 2 次提交
  30. 29 1月, 2008 4 次提交