1. 25 1月, 2008 1 次提交
  2. 16 1月, 2008 1 次提交
  3. 08 12月, 2007 1 次提交
  4. 05 12月, 2007 2 次提交
    • O
      lockdep: in_range() fix · 54561783
      Oleg Nesterov 提交于
      Torsten Kaiser wrote:
      
      | static inline int in_range(const void *start, const void *addr, const void *end)
      | {
      |         return addr >= start && addr <= end;
      | }
      | This  will return true, if addr is in the range of start (including)
      | to end (including).
      |
      | But debug_check_no_locks_freed() seems does:
      | const void *mem_to = mem_from + mem_len
      | -> mem_to is the last byte of the freed range, that fits in_range
      | lock_from = (void *)hlock->instance;
      | -> first byte of the lock
      | lock_to = (void *)(hlock->instance + 1);
      | -> first byte of the next lock, not last byte of the lock that is being checked!
      |
      | The test is:
      | if (!in_range(mem_from, lock_from, mem_to) &&
      |                                         !in_range(mem_from, lock_to, mem_to))
      |                         continue;
      | So it tests, if the first byte of the lock is in the range that is freed ->OK
      | And if the first byte of the *next* lock is in the range that is freed
      | -> Not OK.
      
      We can also simplify in_range checks, we need only 2 comparisons, not 4.
      If the lock is not in memory range, it should be either at the left of range
      or at the right.
      Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      54561783
    • I
      lockdep: fix debug_show_all_locks() · 85684873
      Ingo Molnar 提交于
      fix the oops that can be seen in:
      
         http://bugzilla.kernel.org/attachment.cgi?id=13828&action=view
      
      it is not safe to print the locks of running tasks.
      
      (even with this fix we have a small race - but this is a debug
       function after all.)
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      85684873
  5. 29 10月, 2007 1 次提交
  6. 20 10月, 2007 2 次提交
  7. 12 10月, 2007 2 次提交
  8. 20 7月, 2007 7 次提交
    • J
      lockdep debugging: give stacktrace for init_error · c71063c9
      Johannes Berg 提交于
      When I started adding support for lockdep to 64-bit powerpc, I got a
      lockdep_init_error and with this patch was able to pinpoint why and where
      to put lockdep_init().  Let's support this generally for others adding
      lockdep support to their architecture.
      Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arjan van de Ven <arjan@infradead.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c71063c9
    • P
      lockstat: measure lock bouncing · 96645678
      Peter Zijlstra 提交于
          __acquire
              |
             lock _____
              |        \
              |    __contended
              |         |
              |        wait
              | _______/
              |/
              |
         __acquired
              |
         __release
              |
           unlock
      
      We measure acquisition and contention bouncing.
      
      This is done by recording a cpu stamp in each lock instance.
      
      Contention bouncing requires the cpu stamp to be set on acquisition. Hence we
      move __acquired into the generic path.
      
      __acquired is then used to measure acquisition bouncing by comparing the
      current cpu with the old stamp before replacing it.
      
      __contended is used to measure contention bouncing (only useful for preemptable
      locks)
      
      [akpm@linux-foundation.org: cleanups]
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      96645678
    • P
      lockdep: various fixes · 4b32d0a4
      Peter Zijlstra 提交于
       - update the copyright notices
       - use the default hash function
       - fix a thinko in a BUILD_BUG_ON
       - add a WARN_ON to spot inconsitent naming
       - fix a termination issue in /proc/lock_stat
      
      [akpm@linux-foundation.org: cleanups]
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4b32d0a4
    • P
      lockstat: human readability tweaks · c46261de
      Peter Zijlstra 提交于
      Present all this fancy new lock statistics information:
      
      *warning, _wide_ output ahead*
      
      (output edited for purpose of brevity)
      
       # cat /proc/lock_stat
      lock_stat version 0.1
      -----------------------------------------------------------------------------------------------------------------------------------------------------------------
                                    class name    contentions   waittime-min   waittime-max waittime-total   acquisitions   holdtime-min   holdtime-max holdtime-total
      -----------------------------------------------------------------------------------------------------------------------------------------------------------------
      
                               &inode->i_mutex:         14458           6.57      398832.75     2469412.23        6768876           0.34    11398383.65   339410830.89
                               ---------------
                               &inode->i_mutex           4486          [<ffffffff802a08f9>] pipe_wait+0x86/0x8d
                               &inode->i_mutex              0          [<ffffffff802a01e8>] pipe_write_fasync+0x29/0x5d
                               &inode->i_mutex              0          [<ffffffff802a0e18>] pipe_read+0x74/0x3a5
                               &inode->i_mutex              0          [<ffffffff802a1a6a>] do_lookup+0x81/0x1ae
      
      .................................................................................................................................................................
      
                    &inode->i_data.tree_lock-W:           491           0.27          62.47         493.89        2477833           0.39         468.89     1146584.25
                    &inode->i_data.tree_lock-R:            65           0.44           4.27          48.78       26288792           0.36         184.62    10197458.24
                    --------------------------
                      &inode->i_data.tree_lock             46          [<ffffffff80277095>] __do_page_cache_readahead+0x69/0x24f
                      &inode->i_data.tree_lock             31          [<ffffffff8026f9fb>] add_to_page_cache+0x31/0xba
                      &inode->i_data.tree_lock              0          [<ffffffff802770ee>] __do_page_cache_readahead+0xc2/0x24f
                      &inode->i_data.tree_lock              0          [<ffffffff8026f6e4>] find_get_page+0x1a/0x58
      
      .................................................................................................................................................................
      
                            proc_inum_idr.lock:             0           0.00           0.00           0.00             36           0.00          65.60         148.26
                              proc_subdir_lock:             0           0.00           0.00           0.00        3049859           0.00         106.81     1563212.42
                              shrinker_rwsem-W:             0           0.00           0.00           0.00              5           0.00           1.73           3.68
                              shrinker_rwsem-R:             0           0.00           0.00           0.00            633           2.57         246.57       10909.76
      
      'contentions' and 'acquisitions' are the number of such events measured (since
      the last reset). The waittime- and holdtime- (min, max, total) numbers are
      presented in microseconds.
      
      If there are any contention points, the lock class is presented in the block
      format (as i_mutex and tree_lock above), otherwise a single line of output is
      presented.
      
      The output is sorted on absolute number of contentions (read + write), this
      should get the worst offenders presented first, so that:
      
       # grep : /proc/lock_stat | head
      
      will quickly show who's bad.
      
      The stats can be reset using:
      
       # echo 0 > /proc/lock_stat
      
      [bunk@stusta.de: make 2 functions static]
      [akpm@linux-foundation.org: fix printk warning]
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Acked-by: NJason Baron <jbaron@redhat.com>
      Signed-off-by: NAdrian Bunk <bunk@stusta.de>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c46261de
    • P
      lockstat: core infrastructure · f20786ff
      Peter Zijlstra 提交于
      Introduce the core lock statistics code.
      
      Lock statistics provides lock wait-time and hold-time (as well as the count
      of corresponding contention and acquisitions events). Also, the first few
      call-sites that encounter contention are tracked.
      
      Lock wait-time is the time spent waiting on the lock. This provides insight
      into the locking scheme, that is, a heavily contended lock is indicative of
      a too coarse locking scheme.
      
      Lock hold-time is the duration the lock was held, this provides a reference for
      the wait-time numbers, so they can be put into perspective.
      
        1)
          lock
        2)
          ... do stuff ..
          unlock
        3)
      
      The time between 1 and 2 is the wait-time. The time between 2 and 3 is the
      hold-time.
      
      The lockdep held-lock tracking code is reused, because it already collects locks
      into meaningful groups (classes), and because it is an existing infrastructure
      for lock instrumentation.
      
      Currently lockdep tracks lock acquisition with two hooks:
      
        lock()
          lock_acquire()
          _lock()
      
       ... code protected by lock ...
      
        unlock()
          lock_release()
          _unlock()
      
      We need to extend this with two more hooks, in order to measure contention.
      
        lock_contended() - used to measure contention events
        lock_acquired()  - completion of the contention
      
      These are then placed the following way:
      
        lock()
          lock_acquire()
          if (!_try_lock())
            lock_contended()
            _lock()
            lock_acquired()
      
       ... do locked stuff ...
      
        unlock()
          lock_release()
          _unlock()
      
      (Note: the try_lock() 'trick' is used to avoid instrumenting all platform
             dependent lock primitive implementations.)
      
      It is also possible to toggle the two lockdep features at runtime using:
      
        /proc/sys/kernel/prove_locking
        /proc/sys/kernel/lock_stat
      
      (esp. turning off the O(n^2) prove_locking functionaliy can help)
      
      [akpm@linux-foundation.org: build fixes]
      [akpm@linux-foundation.org: nuke unneeded ifdefs]
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Acked-by: NJason Baron <jbaron@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f20786ff
    • P
      lockdep: reduce the ifdeffery · 8e18257d
      Peter Zijlstra 提交于
      Move code around to get fewer but larger #ifdef sections.  Break some
      in-function #ifdefs out into their own functions.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8e18257d
    • P
      lockdep: sanitise CONFIG_PROVE_LOCKING · ca58abcb
      Peter Zijlstra 提交于
      Ensure that all of the lock dependency tracking code is under
      CONFIG_PROVE_LOCKING.  This allows us to use the held lock tracking code for
      other purposes.
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Acked-by: NJason Baron <jbaron@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ca58abcb
  9. 18 7月, 2007 1 次提交
    • T
      kallsyms: make KSYM_NAME_LEN include space for trailing '\0' · 9281acea
      Tejun Heo 提交于
      KSYM_NAME_LEN is peculiar in that it does not include the space for the
      trailing '\0', forcing all users to use KSYM_NAME_LEN + 1 when allocating
      buffer.  This is nonsense and error-prone.  Moreover, when the caller
      forgets that it's very likely to subtly bite back by corrupting the stack
      because the last position of the buffer is always cleared to zero.
      
      This patch increments KSYM_NAME_LEN by one and updates code accordingly.
      
      * off-by-one bug in asm-powerpc/kprobes.h::kprobe_lookup_name() macro
        is fixed.
      
      * Where MODULE_NAME_LEN and KSYM_NAME_LEN were used together,
        MODULE_NAME_LEN was treated as if it didn't include space for the
        trailing '\0'.  Fix it.
      Signed-off-by: NTejun Heo <htejun@gmail.com>
      Acked-by: NPaulo Marques <pmarques@grupopie.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9281acea
  10. 09 5月, 2007 4 次提交
  11. 23 3月, 2007 1 次提交
  12. 02 3月, 2007 1 次提交
    • S
      [PATCH] fix section mismatch warning in lockdep · 1499993c
      Sam Ravnborg 提交于
      lockdep_init() is marked __init but used in several places
      outside __init code. This causes following warnings:
      $ scripts/mod/modpost kernel/lockdep.o
      WARNING: kernel/built-in.o - Section mismatch: reference to .init.text:lockdep_init from .text.lockdep_init_map after 'lockdep_init_map' (at offset 0x105)
      WARNING: kernel/built-in.o - Section mismatch: reference to .init.text:lockdep_init from .text.lockdep_reset_lock after 'lockdep_reset_lock' (at offset 0x35)
      WARNING: kernel/built-in.o - Section mismatch: reference to .init.text:lockdep_init from .text.__lock_acquire after '__lock_acquire' (at offset 0xb2)
      
      The warnings are less obviously due to heavy inlining by gcc - this is not
      altered.
      
      Fix the section mismatch warnings by removing the __init marking, which
      seems obviously wrong.
      Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
      Acked-by: NIngo Molnar <mingo@elte.hu>
      Cc: <stable@kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      1499993c
  13. 21 2月, 2007 1 次提交
  14. 12 2月, 2007 2 次提交
  15. 31 12月, 2006 1 次提交
  16. 14 12月, 2006 7 次提交
  17. 08 12月, 2006 5 次提交