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  1. 08 8月, 2010 2 次提交
    • W
      ocfs2/dlm: avoid incorrect bit set in refmap on recovery master · a524812b
      Wengang Wang 提交于
      In the following situation, there remains an incorrect bit in refmap on the
      recovery master. Finally the recovery master will fail at purging the lockres
      due to the incorrect bit in refmap.
      
      1) node A has no interest on lockres A any longer, so it is purging it.
      2) the owner of lockres A is node B, so node A is sending de-ref message
      to node B.
      3) at this time, node B crashed. node C becomes the recovery master. it recovers
      lockres A(because the master is the dead node B).
      4) node A migrated lockres A to node C with a refbit there.
      5) node A failed to send de-ref message to node B because it crashed. The failure
      is ignored. no other action is done for lockres A any more.
      
      For mormal, re-send the deref message to it to recovery master can fix it. Well,
      ignoring the failure of deref to the original master and not recovering the lockres
      to recovery master has the same effect. And the later is simpler.
      Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
      Acked-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
      Cc: stable@kernel.org
      Signed-off-by: NJoel Becker <joel.becker@oracle.com>
      a524812b
    • S
      ocfs2 fix o2dlm dlm run purgelist (rev 3) · 7beaf243
      Srinivas Eeda 提交于
      This patch fixes two problems in dlm_run_purgelist
      
      1. If a lockres is found to be in use, dlm_run_purgelist keeps trying to purge
      the same lockres instead of trying the next lockres.
      
      2. When a lockres is found unused, dlm_run_purgelist releases lockres spinlock
      before setting DLM_LOCK_RES_DROPPING_REF and calls dlm_purge_lockres.
      spinlock is reacquired but in this window lockres can get reused. This leads
      to BUG.
      
      This patch modifies dlm_run_purgelist to skip lockres if it's in use and purge
       next lockres. It also sets DLM_LOCK_RES_DROPPING_REF before releasing the
      lockres spinlock protecting it from getting reused.
      Signed-off-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
      Acked-by: NSunil Mushran <sunil.mushran@oracle.com>
      Cc: stable@kernel.org
      Signed-off-by: NJoel Becker <joel.becker@oracle.com>
      7beaf243
  2. 19 5月, 2010 1 次提交
    • W
      ocfs2:dlm: avoid dlm->ast_lock lockres->spinlock dependency break · d9ef7522
      Wengang Wang 提交于
      Currently we process a dirty lockres with the lockres->spinlock taken. While
      during the process, we may need to lock on dlm->ast_lock. This breaks the
      dependency of dlm->ast_lock(lock first) and lockres->spinlock(lock second).
      
      This patch fixes the problem.
      Since we can't release lockres->spinlock, we have to take dlm->ast_lock
      just before taking the lockres->spinlock and release it after lockres->spinlock
      is released. And use __dlm_queue_bast()/__dlm_queue_ast(), the nolock version,
      in dlm_shuffle_lists(). There are no too many locks on a lockres, so there is no
      performance harm.
      Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
      Signed-off-by: NJoel Becker <joel.becker@oracle.com>
      d9ef7522
  3. 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
  4. 24 9月, 2009 1 次提交
  5. 23 9月, 2009 1 次提交
  6. 04 4月, 2009 1 次提交
  7. 27 2月, 2009 1 次提交
  8. 06 1月, 2009 1 次提交
  9. 11 3月, 2008 1 次提交
  10. 03 5月, 2007 1 次提交
  11. 27 3月, 2007 1 次提交
  12. 15 3月, 2007 1 次提交
  13. 08 2月, 2007 4 次提交
  14. 27 6月, 2006 7 次提交
  15. 04 1月, 2006 2 次提交