1. 15 10月, 2009 3 次提交
    • P
      rcu: Stopgap fix for synchronize_rcu_expedited() for TREE_PREEMPT_RCU · 019129d5
      Paul E. McKenney 提交于
      For the short term, map synchronize_rcu_expedited() to
      synchronize_rcu() for TREE_PREEMPT_RCU and to
      synchronize_sched_expedited() for TREE_RCU.
      
      Longer term, there needs to be a real expedited grace period for
      TREE_PREEMPT_RCU, but candidate patches to date are considerably
      more complex and intrusive.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      Cc: npiggin@suse.de
      Cc: jens.axboe@oracle.com
      LKML-Reference: <12555405592331-git-send-email->
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      019129d5
    • P
      rcu: Prevent RCU IPI storms in presence of high call_rcu() load · 37c72e56
      Paul E. McKenney 提交于
      As the number of callbacks on a given CPU rises, invoke
      force_quiescent_state() only every blimit number of callbacks
      (defaults to 10,000), and even then only if no other CPU has
      invoked force_quiescent_state() in the meantime.
      
      This should fix the performance regression reported by Nick.
      Reported-by: NNick Piggin <npiggin@suse.de>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      Cc: jens.axboe@oracle.com
      LKML-Reference: <12555405592133-git-send-email->
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      37c72e56
    • D
      futex: Check for NULL keys in match_futex · 2bc87203
      Darren Hart 提交于
      If userspace tries to perform a requeue_pi on a non-requeue_pi waiter,
      it will find the futex_q->requeue_pi_key to be NULL and OOPS.
      
      Check for NULL in match_futex() instead of doing explicit NULL pointer
      checks on all call sites.  While match_futex(NULL, NULL) returning
      false is a little odd, it's still correct as we expect valid key
      references.
      Signed-off-by: NDarren Hart <dvhltc@us.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      CC: Eric Dumazet <eric.dumazet@gmail.com>
      CC: Dinakar Guniguntala <dino@in.ibm.com>
      CC: John Stultz <johnstul@us.ibm.com>
      Cc: stable@kernel.org
      LKML-Reference: <4AD60687.10306@us.ibm.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      2bc87203
  2. 14 10月, 2009 1 次提交
    • T
      futex: Handle spurious wake up · d58e6576
      Thomas Gleixner 提交于
      The futex code does not handle spurious wake up in futex_wait and
      futex_wait_requeue_pi.
      
      The code assumes that any wake up which was not caused by futex_wake /
      requeue or by a timeout was caused by a signal wake up and returns one
      of the syscall restart error codes.
      
      In case of a spurious wake up the signal delivery code which deals
      with the restart error codes is not invoked and we return that error
      code to user space. That causes applications which actually check the
      return codes to fail. Blaise reported that on preempt-rt a python test
      program run into a exception trap. -rt exposed that due to a built in
      spurious wake up accelerator :)
      
      Solve this by checking signal_pending(current) in the wake up path and
      handle the spurious wake up case w/o returning to user space.
      Reported-by: NBlaise Gassend <blaise@willowgarage.com>
      Debugged-by: NDarren Hart <dvhltc@us.ibm.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: stable@kernel.org
      LKML-Reference: <new-submission>
      d58e6576
  3. 09 10月, 2009 1 次提交
  4. 08 10月, 2009 6 次提交
  5. 07 10月, 2009 4 次提交
    • E
      NOHZ: update idle state also when NOHZ is inactive · fdc6f192
      Eero Nurkkala 提交于
      Commit f2e21c96 had unfortunate side
      effects with cpufreq governors on some systems.
      
      If the system did not switch into NOHZ mode ts->inidle is not set when
      tick_nohz_stop_sched_tick() is called from the idle routine. Therefor
      all subsequent calls from irq_exit() to tick_nohz_stop_sched_tick()
      fail to call tick_nohz_start_idle(). This results in bogus idle
      accounting information which is passed to cpufreq governors.
      
      Set the inidle flag unconditionally of the NOHZ active state to keep
      the idle time accounting correct in any case.
      
      [ tglx: Added comment and tweaked the changelog ]
      Reported-by: NSteven Noonan <steven@uplinklabs.net>
      Signed-off-by: NEero Nurkkala <ext-eero.nurkkala@nokia.com>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
      Cc: Greg KH <greg@kroah.com>
      Cc: Steven Noonan <steven@uplinklabs.net>
      Cc: stable@kernel.org
      LKML-Reference: <1254907901.30157.93.camel@eenurkka-desktop>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      fdc6f192
    • P
      rcu: Place root rcu_node structure in separate lockdep class · 978c0b88
      Paul E. McKenney 提交于
      Before this patch, all of the rcu_node structures were in the same lockdep
      class, so that lockdep would complain when rcu_preempt_offline_tasks()
      acquired the root rcu_node structure's lock while holding one of the leaf
      rcu_nodes' locks.
      
      This patch changes rcu_init_one() to use a separate
      spin_lock_init() for the root rcu_node structure's lock than is
      used for that of all of the rest of the rcu_node structures, which
      puts the root rcu_node structure's lock in its own lockdep class.
      Suggested-by: NPeter Zijlstra <peterz@infradead.org>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: akpm@linux-foundation.org
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <12548908983277-git-send-email->
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      978c0b88
    • P
      rcu: Make hot-unplugged CPU relinquish its own RCU callbacks · e74f4c45
      Paul E. McKenney 提交于
      The current interaction between RCU and CPU hotplug requires that
      RCU block in CPU notifiers waiting for callbacks to drain.
      
      This can be greatly simplified by having each CPU relinquish its
      own callbacks, and for both _rcu_barrier() and CPU_DEAD notifiers
      to adopt all callbacks that were previously relinquished.
      
      This change also eliminates the possibility of certain types of
      hangs due to the previous practice of waiting for callbacks to be
      invoked from within CPU notifiers.  If you don't every wait, you
      cannot hang.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: akpm@linux-foundation.org
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1254890898456-git-send-email->
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      e74f4c45
    • P
      rcu: Move rcu_barrier() to rcutree · d0ec774c
      Paul E. McKenney 提交于
      Move the existing rcu_barrier() implementation to rcutree.c,
      consistent with the fact that the rcu_barrier() implementation is
      tied quite tightly to the RCU implementation.
      
      This opens the way to simplify and fix rcutree.c's rcu_barrier()
      implementation in a later patch.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: akpm@linux-foundation.org
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <12548908982563-git-send-email->
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d0ec774c
  6. 06 10月, 2009 11 次提交
  7. 05 10月, 2009 3 次提交
  8. 02 10月, 2009 6 次提交
    • K
      memcg: some modification to softlimit under hierarchical memory reclaim. · 4e649152
      KAMEZAWA Hiroyuki 提交于
      This patch clean up/fixes for memcg's uncharge soft limit path.
      
      Problems:
        Now, res_counter_charge()/uncharge() handles softlimit information at
        charge/uncharge and softlimit-check is done when event counter per memcg
        goes over limit. Now, event counter per memcg is updated only when
        memory usage is over soft limit. Here, considering hierarchical memcg
        management, ancesotors should be taken care of.
      
        Now, ancerstors(hierarchy) are handled in charge() but not in uncharge().
        This is not good.
      
        Prolems:
        1. memcg's event counter incremented only when softlimit hits. That's bad.
           It makes event counter hard to be reused for other purpose.
      
        2. At uncharge, only the lowest level rescounter is handled. This is bug.
           Because ancesotor's event counter is not incremented, children should
           take care of them.
      
        3. res_counter_uncharge()'s 3rd argument is NULL in most case.
           ops under res_counter->lock should be small. No "if" sentense is better.
      
      Fixes:
        * Removed soft_limit_xx poitner and checks in charge and uncharge.
          Do-check-only-when-necessary scheme works enough well without them.
      
        * make event-counter of memcg incremented at every charge/uncharge.
          (per-cpu area will be accessed soon anyway)
      
        * All ancestors are checked at soft-limit-check. This is necessary because
          ancesotor's event counter may never be modified. Then, they should be
          checked at the same time.
      Reviewed-by: NDaisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
      Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Paul Menage <menage@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4e649152
    • K
      cgroup: catch bad css refcnt at css_put · 3dece834
      KAMEZAWA Hiroyuki 提交于
      __css_put() doesn't check a bug as refcnt goes to minus.
      I think it should be caught. This patch adds a check for it.
      Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Paul Menage <menage@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Balbir Singh <balbir@in.ibm.com>
      Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3dece834
    • A
      const: constify remaining file_operations · 828c0950
      Alexey Dobriyan 提交于
      [akpm@linux-foundation.org: fix KVM]
      Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
      Acked-by: NMike Frysinger <vapier@gentoo.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      828c0950
    • P
      module: fix up CONFIG_KALLSYMS=n build. · 3ae91c21
      Paul Mundt 提交于
      Starting from commit 4a496226 "reduce
      symbol table for loaded modules (v2)", the kernel/module.c build is broken
      with CONFIG_KALLSYMS disabled.
      
        CC      kernel/module.o
      kernel/module.c:1995: warning: type defaults to 'int' in declaration of 'Elf_Hdr'
      kernel/module.c:1995: error: expected ';', ',' or ')' before '*' token
      kernel/module.c: In function 'load_module':
      kernel/module.c:2203: error: 'strmap' undeclared (first use in this function)
      kernel/module.c:2203: error: (Each undeclared identifier is reported only once
      kernel/module.c:2203: error: for each function it appears in.)
      kernel/module.c:2239: error: 'symoffs' undeclared (first use in this function)
      kernel/module.c:2239: error: implicit declaration of function 'layout_symtab'
      kernel/module.c:2240: error: 'stroffs' undeclared (first use in this function)
      make[1]: *** [kernel/module.o] Error 1
      make: *** [kernel/module.o] Error 2
      
      There are three different issues:
      
          - layout_symtab() takes a const Elf_Ehdr
      
          - layout_symtab() needs to return a value
      
          - symoffs/stroffs/strmap are referenced by the load_module() code
            despite being ifdefed out, which seems unnecessary given the noop
            behaviour of layout_symtab()/add_kallsyms() in the case of
            CONFIG_KALLSYMS=n.
      Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
      Acked-by: NJan Beulich <jbeulich@novell.com>
      Acked-by: NRusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3ae91c21
    • J
      Add a tracepoint for block request remapping · b0da3f0d
      Jun'ichi Nomura 提交于
      Since 2.6.31 now has request-based device-mapper, it's useful to have
      a tracepoint for request-remapping as well as bio-remapping.
      This patch adds a tracepoint for request-remapping, trace_block_rq_remap().
      Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
      Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
      Cc: Alasdair G Kergon <agk@redhat.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      b0da3f0d
    • Z
      Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs · 48c0d4d4
      Zdenek Kabelac 提交于
      Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs
      introduced in commit 1d54ad6d.
      Release kobject also in case the request_fn is NULL.
      
      Problem was noticed via kmemleak backtrace when some sysfs entries were
      note properly destroyed during  device removal:
      
      unreferenced object 0xffff88001aa76640 (size 80):
        comm "lvcreate", pid 2120, jiffies 4294885144
        hex dump (first 32 bytes):
          01 00 00 00 00 00 00 00 f0 65 a7 1a 00 88 ff ff  .........e......
          90 66 a7 1a 00 88 ff ff 86 1d 53 81 ff ff ff ff  .f........S.....
        backtrace:
          [<ffffffff813f9cc6>] kmemleak_alloc+0x26/0x60
          [<ffffffff8111d693>] kmem_cache_alloc+0x133/0x1c0
          [<ffffffff81195891>] sysfs_new_dirent+0x41/0x120
          [<ffffffff81194b0c>] sysfs_add_file_mode+0x3c/0xb0
          [<ffffffff81197c81>] internal_create_group+0xc1/0x1a0
          [<ffffffff81197d93>] sysfs_create_group+0x13/0x20
          [<ffffffff810d8004>] blk_trace_init_sysfs+0x14/0x20
          [<ffffffff8123f45c>] blk_register_queue+0x3c/0xf0
          [<ffffffff812447e4>] add_disk+0x94/0x160
          [<ffffffffa00d8b08>] dm_create+0x598/0x6e0 [dm_mod]
          [<ffffffffa00de951>] dev_create+0x51/0x350 [dm_mod]
          [<ffffffffa00de823>] ctl_ioctl+0x1a3/0x240 [dm_mod]
          [<ffffffffa00de8f2>] dm_compat_ctl_ioctl+0x12/0x20 [dm_mod]
          [<ffffffff81177bfd>] compat_sys_ioctl+0xcd/0x4f0
          [<ffffffff81036ed8>] sysenter_dispatch+0x7/0x2c
          [<ffffffffffffffff>] 0xffffffffffffffff
      Signed-off-by: NZdenek Kabelac <zkabelac@redhat.com>
      Reviewed-by: NLi Zefan <lizf@cn.fujitsu.com>
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      48c0d4d4
  9. 01 10月, 2009 5 次提交