1. 14 5月, 2010 1 次提交
  2. 11 5月, 2010 1 次提交
    • C
      sched, wait: Use wrapper functions · a93d2f17
      Changli Gao 提交于
      epoll should not touch flags in wait_queue_t. This patch introduces a new
      function __add_wait_queue_exclusive(), for the users, who use wait queue as a
      LIFO queue.
      
      __add_wait_queue_tail_exclusive() is introduced too instead of
      add_wait_queue_exclusive_locked(). remove_wait_queue_locked() is removed, as
      it is a duplicate of __remove_wait_queue(), disliked by users, and with less
      users.
      Signed-off-by: NChangli Gao <xiaosuo@gmail.com>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Paul Menage <menage@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Davide Libenzi <davidel@xmailserver.org>
      Cc: <containers@lists.linux-foundation.org>
      LKML-Reference: <1273214006-2979-1-git-send-email-xiaosuo@gmail.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      a93d2f17
  3. 10 5月, 2010 9 次提交
  4. 09 5月, 2010 1 次提交
  5. 08 5月, 2010 1 次提交
    • T
      cpu_stop: add dummy implementation for UP · bbf1bb3e
      Tejun Heo 提交于
      When !CONFIG_SMP, cpu_stop functions weren't defined at all which
      could lead to build failures if UP code uses cpu_stop facility.  Add
      dummy cpu_stop implementation for UP.  The waiting variants execute
      the work function directly with preempt disabled and
      stop_one_cpu_nowait() schedules a workqueue work.
      
      Makefile and ifdefs around stop_machine implementation are updated to
      accomodate CONFIG_SMP && !CONFIG_STOP_MACHINE case.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reported-by: NIngo Molnar <mingo@elte.hu>
      bbf1bb3e
  6. 07 5月, 2010 8 次提交
    • P
      sched: Remove rq argument to the tracepoints · 27a9da65
      Peter Zijlstra 提交于
      struct rq isn't visible outside of sched.o so its near useless to
      expose the pointer, also there are no users of it, so remove it.
      Acked-by: NSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      LKML-Reference: <1272997616.1642.207.camel@laptop>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      27a9da65
    • I
      Merge commit 'v2.6.34-rc6' into sched/core · 48652ced
      Ingo Molnar 提交于
      48652ced
    • P
      rcu: need barrier() in UP synchronize_sched_expedited() · fc390cde
      Paul E. McKenney 提交于
      If synchronize_sched_expedited() is ever to be called from within
      kernel/sched.c in a !SMP PREEMPT kernel, the !SMP implementation needs
      a barrier().
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: NTejun Heo <tj@kernel.org>
      fc390cde
    • P
      sched: correctly place paranioa memory barriers in synchronize_sched_expedited() · cc631fb7
      Paul E. McKenney 提交于
      The memory barriers must be in the SMP case, not in the !SMP case.
      Also add a barrier after the atomic_inc() in order to ensure that
      other CPUs see post-synchronize_sched_expedited() actions as following
      the expedited grace period.
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: NTejun Heo <tj@kernel.org>
      cc631fb7
    • T
      sched: kill paranoia check in synchronize_sched_expedited() · 94458d5e
      Tejun Heo 提交于
      The paranoid check which verifies that the cpu_stop callback is
      actually called on all online cpus is completely superflous.  It's
      guaranteed by cpu_stop facility and if it didn't work as advertised
      other things would go horribly wrong and trying to recover using
      synchronize_sched() wouldn't be very meaningful.
      
      Kill the paranoid check.  Removal of this feature is done as a
      separate step so that it can serve as a bisection point if something
      actually goes wrong.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Dipankar Sarma <dipankar@in.ibm.com>
      Cc: Josh Triplett <josh@freedesktop.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Dimitri Sivanich <sivanich@sgi.com>
      94458d5e
    • T
      sched: replace migration_thread with cpu_stop · 969c7921
      Tejun Heo 提交于
      Currently migration_thread is serving three purposes - migration
      pusher, context to execute active_load_balance() and forced context
      switcher for expedited RCU synchronize_sched.  All three roles are
      hardcoded into migration_thread() and determining which job is
      scheduled is slightly messy.
      
      This patch kills migration_thread and replaces all three uses with
      cpu_stop.  The three different roles of migration_thread() are
      splitted into three separate cpu_stop callbacks -
      migration_cpu_stop(), active_load_balance_cpu_stop() and
      synchronize_sched_expedited_cpu_stop() - and each use case now simply
      asks cpu_stop to execute the callback as necessary.
      
      synchronize_sched_expedited() was implemented with private
      preallocated resources and custom multi-cpu queueing and waiting
      logic, both of which are provided by cpu_stop.
      synchronize_sched_expedited_count is made atomic and all other shared
      resources along with the mutex are dropped.
      
      synchronize_sched_expedited() also implemented a check to detect cases
      where not all the callback got executed on their assigned cpus and
      fall back to synchronize_sched().  If called with cpu hotplug blocked,
      cpu_stop already guarantees that and the condition cannot happen;
      otherwise, stop_machine() would break.  However, this patch preserves
      the paranoid check using a cpumask to record on which cpus the stopper
      ran so that it can serve as a bisection point if something actually
      goes wrong theree.
      
      Because the internal execution state is no longer visible,
      rcu_expedited_torture_stats() is removed.
      
      This patch also renames cpu_stop threads to from "stopper/%d" to
      "migration/%d".  The names of these threads ultimately don't matter
      and there's no reason to make unnecessary userland visible changes.
      
      With this patch applied, stop_machine() and sched now share the same
      resources.  stop_machine() is faster without wasting any resources and
      sched migration users are much cleaner.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Dipankar Sarma <dipankar@in.ibm.com>
      Cc: Josh Triplett <josh@freedesktop.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Dimitri Sivanich <sivanich@sgi.com>
      969c7921
    • T
      stop_machine: reimplement using cpu_stop · 3fc1f1e2
      Tejun Heo 提交于
      Reimplement stop_machine using cpu_stop.  As cpu stoppers are
      guaranteed to be available for all online cpus,
      stop_machine_create/destroy() are no longer necessary and removed.
      
      With resource management and synchronization handled by cpu_stop, the
      new implementation is much simpler.  Asking the cpu_stop to execute
      the stop_cpu() state machine on all online cpus with cpu hotplug
      disabled is enough.
      
      stop_machine itself doesn't need to manage any global resources
      anymore, so all per-instance information is rolled into struct
      stop_machine_data and the mutex and all static data variables are
      removed.
      
      The previous implementation created and destroyed RT workqueues as
      necessary which made stop_machine() calls highly expensive on very
      large machines.  According to Dimitri Sivanich, preventing the dynamic
      creation/destruction makes booting faster more than twice on very
      large machines.  cpu_stop resources are preallocated for all online
      cpus and should have the same effect.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NRusty Russell <rusty@rustcorp.com.au>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Dimitri Sivanich <sivanich@sgi.com>
      3fc1f1e2
    • T
      cpu_stop: implement stop_cpu[s]() · 1142d810
      Tejun Heo 提交于
      Implement a simplistic per-cpu maximum priority cpu monopolization
      mechanism.  A non-sleeping callback can be scheduled to run on one or
      multiple cpus with maximum priority monopolozing those cpus.  This is
      primarily to replace and unify RT workqueue usage in stop_machine and
      scheduler migration_thread which currently is serving multiple
      purposes.
      
      Four functions are provided - stop_one_cpu(), stop_one_cpu_nowait(),
      stop_cpus() and try_stop_cpus().
      
      This is to allow clean sharing of resources among stop_cpu and all the
      migration thread users.  One stopper thread per cpu is created which
      is currently named "stopper/CPU".  This will eventually replace the
      migration thread and take on its name.
      
      * This facility was originally named cpuhog and lived in separate
        files but Peter Zijlstra nacked the name and thus got renamed to
        cpu_stop and moved into stop_machine.c.
      
      * Better reporting of preemption leak as per Peter's suggestion.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Dimitri Sivanich <sivanich@sgi.com>
      1142d810
  7. 06 5月, 2010 1 次提交
  8. 05 5月, 2010 3 次提交
  9. 04 5月, 2010 1 次提交
    • S
      tracing: Convert nop macros to static inlines · 4dbf6bc2
      Steven Rostedt 提交于
      The ftrace.h file contains several functions as macros when the
      functions are disabled due to config options. This patch converts
      most of them to static inlines.
      
      There are two exceptions:
      
        register_ftrace_function() and unregister_ftrace_function()
      
      This is because their parameter "ops" must not be evaluated since
      code using the function is allowed to #ifdef out the creation of
      the parameter.
      
      This also fixes an error caused by recent changes:
      
       kernel/trace/trace_irqsoff.c: In function 'start_irqsoff_tracer':
       kernel/trace/trace_irqsoff.c:571: error: expected expression before 'do'
      Reported-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      4dbf6bc2
  10. 30 4月, 2010 12 次提交
  11. 29 4月, 2010 2 次提交