Commit graph

8405 commits

Author SHA1 Message Date
Linus Torvalds
d6047d79b9 Merge branch 'tty-fixes'
* branch 'tty-fixes':
  tty: use the new 'flush_delayed_work()' helper to do ldisc flush
  workqueue: add 'flush_delayed_work()' to run and wait for delayed work
  Make flush_to_ldisc properly handle parallel calls
2009-10-14 15:34:55 -07:00
Linus Torvalds
ee67e6cbe1 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  oprofile: warn on freeing event buffer too early
  oprofile: fix race condition in event_buffer free
  lockdep: Use cpu_clock() for lockstat
2009-10-14 15:25:35 -07:00
Linus Torvalds
f061d83a2b Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Fix missing kernel-doc notation
  Revert "x86, timers: Check for pending timers after (device) interrupts"
  sched: Update the clock of runqueue select_task_rq() selected
2009-10-14 15:25:04 -07:00
Linus Torvalds
e345fe1ada Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing/filters: Fix memory leak when setting a filter
  tracing: fix trace_vprintk call
2009-10-14 15:24:51 -07:00
Linus Torvalds
8c53e46314 workqueue: add 'flush_delayed_work()' to run and wait for delayed work
It basically turns a delayed work into an immediate work, and then waits
for it to finish, thus allowing you to force (and wait for) an immediate
flush of a delayed work.

We'll want to use this in the tty layer to clean up tty_flush_to_ldisc().

Acked-by: Oleg Nesterov <oleg@redhat.com>
[ Fixed to use 'del_timer_sync()' as noted by Oleg ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-14 15:11:35 -07:00
Darren Hart
2bc872036e futex: Check for NULL keys in match_futex
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: Darren 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: Thomas Gleixner <tglx@linutronix.de>
2009-10-14 22:00:14 +02:00
Linus Torvalds
43046b6066 workqueue: add 'flush_delayed_work()' to run and wait for delayed work
It basically turns a delayed work into an immediate work, and then waits
for it to finish.
2009-10-14 09:16:42 -07:00
Peter Zijlstra
92f6a5e37a sched: Do less agressive buddy clearing
Yanmin reported a hackbench regression due to:

 > commit de69a80be3
 > Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
 > Date:   Thu Sep 17 09:01:20 2009 +0200
 >
 >     sched: Stop buddies from hogging the system

I really liked de69a80b, and it affecting hackbench shows I wasn't
crazy ;-)

So hackbench is a multi-cast, with one sender spraying multiple
receivers, who in their turn don't spray back.

This would be exactly the scenario that patch 'cures'. Previously
we would not clear the last buddy after running the next task,
allowing the sender to get back to work sooner than it otherwise
ought to have been, increasing latencies for other tasks.

Now, since those receivers don't poke back, they don't enforce the
buddy relation, which means there's nothing to re-elect the sender.

Cure this by less agressively clearing the buddy stats. Only clear
buddies when they were not chosen. It should still avoid a buddy
sticking around long after its served its time.

Reported-by: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1255084986.8802.46.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-14 15:02:34 +02:00
Paul Mackerras
03541f8b69 perf_event: Adjust frequency and unthrottle for non-group-leader events
The loop in perf_ctx_adjust_freq checks the frequency of sampling
event counters, and adjusts the event interval and unthrottles the
event if required, and resets the interrupt count for the event.
However, at present it only looks at group leaders.

This means that a sampling event that is not a group leader will
eventually get throttled, once its interrupt count reaches
sysctl_perf_event_sample_rate/HZ --- and that is guaranteed to
happen, if the event is active for long enough, since the interrupt
count never gets reset.  Once it is throttled it never gets
unthrottled, so it basically just stops working at that point.

This fixes it by making perf_ctx_adjust_freq use ctx->event_list
rather than ctx->group_list.  The existing spin_lock/spin_unlock
around the loop makes it unnecessary to put rcu_read_lock/
rcu_read_unlock around the list_for_each_entry_rcu().

Reported-by: Mark W. Krentel <krentel@cs.rice.edu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <19157.26731.855609.165622@cargo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-14 08:39:32 +02:00
Thomas Gleixner
d58e6576b0 futex: Handle spurious wake up
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: Blaise Gassend <blaise@willowgarage.com>
Debugged-by: Darren Hart <dvhltc@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@kernel.org
LKML-Reference: <new-submission>
2009-10-13 20:40:43 +02:00
Linus Torvalds
80f506918f Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cciss: Add cciss_allow_hpsa module parameter
  cciss: Fix multiple calls to pci_release_regions
  blk-settings: fix function parameter kernel-doc notation
  writeback: kill space in debugfs item name
  writeback: account IO throttling wait as iowait
  elv_iosched_store(): fix strstrip() misuse
  cfq-iosched: avoid probable slice overrun when idling
  cfq-iosched: apply bool value where we return 0/1
  cfq-iosched: fix think time allowed for seekers
  cfq-iosched: fix the slice residual sign
  cfq-iosched: abstract out the 'may this cfqq dispatch' logic
  block: use proper BLK_RW_ASYNC in blk_queue_start_tag()
  block: Seperate read and write statistics of in_flight requests v2
  block: get rid of kblock_schedule_delayed_work()
  cfq-iosched: fix possible problem with jiffies wraparound
  cfq-iosched: fix issue with rq-rq merging and fifo list ordering
2009-10-13 10:21:33 -07:00
Li Zefan
8ad807318f tracing/filters: Fix memory leak when setting a filter
Every time we set a filter, we leak memory allocated by
postfix_append_operand() and postfix_append_op().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: <stable@kernel.org> # for v2.6.31.x
LKML-Reference: <4AD3D7D9.4070400@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-13 08:05:17 +02:00
Randy Dunlap
e17b38bf9e sched: Fix missing kernel-doc notation
The following htmldocs warnings:

  Warning(kernel/sched.c:685): No description found for parameter 'cpu'
  Warning(kernel/sched.c:3676): No description found for parameter 'sd'

Trigger because new parameters were added to update_rq_clock() and
update_group_power() without updating the kernel-doc notation.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4AD29070.7070002@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-12 10:50:06 +02:00
Alexey Dobriyan
d43c36dc6b headers: remove sched.h from interrupt.h
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-10-11 11:20:58 -07:00
Mike Galbraith
f5dc37530b sched: Update the clock of runqueue select_task_rq() selected
In try_to_wake_up(), we update the runqueue clock, but
select_task_rq() may select a different runqueue than the one we
updated, leaving the new runqueue's clock stale for a bit.

This patch cures occasional huge latencies reported by latencytop
when coming out of idle on a mostly idle NO_HZ box.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1255070103.7639.30.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-09 15:58:11 +02:00
Peter Zijlstra
3365e77987 lockdep: Use cpu_clock() for lockstat
Some tracepoint magic (TRACE_EVENT(lock_acquired)) relies on
the fact that lock hold times are positive and uses div64 on
that. That triggered a build warning on MIPS, and probably
causes bad output in certain circumstances as well.

Make it truly positive.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1254818502.21044.112.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-09 15:56:44 +02:00
Wu Fengguang
d25105e891 writeback: account IO throttling wait as iowait
It makes sense to do IOWAIT when someone is blocked
due to IO throttle, as suggested by Kame and Peter.

There is an old comment for not doing IOWAIT on throttle,
however it has been mismatching the code for a long time.

If we stop accounting IOWAIT for 2.6.32, it could be an
undesirable behavior change. So restore the io_schedule.

CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-09 12:40:42 +02:00
Steven Rostedt
a813a15976 tracing: fix trace_vprintk call
The addition of trace_array_{v}printk used the wrong function for
trace_vprintk to call. This broke trace_marker and trace_vprintk
itself. Although trace_printk may not have been affected by those
that end up calling trace_vbprintk.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-10-09 01:41:35 -04:00
Linus Torvalds
f579bbcd9b Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  futex: fix requeue_pi key imbalance
  futex: Fix typo in FUTEX_WAIT/WAKE_BITSET_PRIVATE definitions
  rcu: Place root rcu_node structure in separate lockdep class
  rcu: Make hot-unplugged CPU relinquish its own RCU callbacks
  rcu: Move rcu_barrier() to rcutree
  futex: Move exit_pi_state() call to release_mm()
  futex: Nullify robust lists after cleanup
  futex: Fix locking imbalance
  panic: Fix panic message visibility by calling bust_spinlocks(0) before dying
  rcu: Replace the rcu_barrier enum with pointer to call_rcu*() function
  rcu: Clean up code based on review feedback from Josh Triplett, part 4
  rcu: Clean up code based on review feedback from Josh Triplett, part 3
  rcu: Fix rcu_lock_map build failure on CONFIG_PROVE_LOCKING=y
  rcu: Clean up code to address Ingo's checkpatch feedback
  rcu: Clean up code based on review feedback from Josh Triplett, part 2
  rcu: Clean up code based on review feedback from Josh Triplett
2009-10-08 12:16:35 -07:00
Linus Torvalds
e80fb7e52f Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: Set correct normal_prio and prio values in sched_fork()
2009-10-08 12:07:24 -07:00
Linus Torvalds
f17f36bb1c Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: user local buffer variable for trace branch tracer
  tracing: fix warning on kernel/trace/trace_branch.c andtrace_hw_branches.c
  ftrace: check for failure for all conversions
  tracing: correct module boundaries for ftrace_release
  tracing: fix transposed numbers of lock_depth and preempt_count
  trace: Fix missing assignment in trace_ctxwake_*
  tracing: Use free_percpu instead of kfree
  tracing: Check total refcount before releasing bufs in profile_enable failure
2009-10-08 12:06:09 -07:00
Linus Torvalds
b924f9599d Merge branch 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sparc-perf-events-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  mm, perf_event: Make vmalloc_user() align base kernel virtual address to SHMLBA
  perf_event: Provide vmalloc() based mmap() backing
2009-10-08 12:05:50 -07:00
Linus Torvalds
b9d40b7b1e Merge branch 'perf-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf_events: Make ABI definitions available to userspace
  perf tools: elf_sym__is_function() should accept "zero" sized functions
  tracing/syscalls: Use long for syscall ret format and field definitions
  perf trace: Update eval_flag() flags array to match interrupt.h
  perf trace: Remove unused code in builtin-trace.c
  perf: Propagate term signal to child
2009-10-08 12:05:00 -07:00
Steven Rostedt
8f6e8a314a tracing: user local buffer variable for trace branch tracer
Just using the tr->buffer for the API to trace_buffer_lock_reserve
is not good enough. This is because the tr->buffer may change, and we
do not want to commit with a different buffer that we reserved from.

This patch uses a local variable to hold the buffer that was used to
reserve and commit with.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-10-07 21:53:41 -04:00
Zhenwen Xu
c8647b2872 tracing: fix warning on kernel/trace/trace_branch.c andtrace_hw_branches.c
fix warnings that caused the API change of trace_buffer_lock_reserve()
change files: kernel/trace/trace_hw_branch.c
              kernel/trace/trace_branch.c

Signed-off-by: Zhenwen Xu <helight.xu@gmail.com>
LKML-Reference: <20091008012146.GA4170@helight>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-10-07 21:52:03 -04:00
Steven Rostedt
3279ba37db ftrace: check for failure for all conversions
Due to legacy code from back when the dynamic tracer used a daemon,
only core kernel code was checking for failures. This is no longer
the case. We must check for failures any time we perform text modifications.

Cc: stable@kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-10-07 17:22:24 -04:00
jolsa@redhat.com
e7247a15ff tracing: correct module boundaries for ftrace_release
When the module is about the unload we release its call records.
The ftrace_release function was given wrong values representing
the module core boundaries, thus not releasing its call records.

Plus making ftrace_release function module specific.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1254934835-363-3-git-send-email-jolsa@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-10-07 15:52:09 -04:00
Darren Hart
da08568101 futex: fix requeue_pi key imbalance
If futex_wait_requeue_pi() wakes prior to requeue, we drop the
reference to the source futex_key twice, once in
handle_early_requeue_pi_wakeup() and once on our way out.

Remove the drop from the handle_early_requeue_pi_wakeup() and keep
the get/drops together in futex_wait_requeue_pi().

Reported-by: Helge Bahmann <hcb@chaoticmind.net>
Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Helge Bahmann <hcb@chaoticmind.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Dinakar Guniguntala <dino@in.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: stable-2.6.31 <stable@kernel.org>
LKML-Reference: <4ACCE21E.5030805@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-10-07 21:22:03 +02:00
Steven Rostedt
829b876dfc tracing: fix transposed numbers of lock_depth and preempt_count
The lock_depth and preempt_count numbers in the latency format is
transposed.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-10-07 14:05:04 -04:00
Eero Nurkkala
fdc6f192e7 NOHZ: update idle state also when NOHZ is inactive
Commit f2e21c9610 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: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Eero 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: Thomas Gleixner <tglx@linutronix.de>
2009-10-07 13:05:05 +02:00
Paul E. McKenney
978c0b8814 rcu: Place root rcu_node structure in separate lockdep class
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: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul 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: Ingo Molnar <mingo@elte.hu>
2009-10-07 08:11:21 +02:00
Paul E. McKenney
e74f4c4564 rcu: Make hot-unplugged CPU relinquish its own RCU callbacks
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: Paul 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: Ingo Molnar <mingo@elte.hu>
2009-10-07 08:11:20 +02:00
Paul E. McKenney
d0ec774cb2 rcu: Move rcu_barrier() to rcutree
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: Paul 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: Ingo Molnar <mingo@elte.hu>
2009-10-07 08:11:20 +02:00
Thomas Gleixner
322a2c100a futex: Move exit_pi_state() call to release_mm()
exit_pi_state() is called from do_exit() but not from do_execve().
Move it to release_mm() so it gets called from do_execve() as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: stable@kernel.org
Cc: Anirban Sinha <ani@anirban.org>
Cc: Peter Zijlstra <peterz@infradead.org>
2009-10-06 17:00:01 +02:00
Peter Zijlstra
fc6b177dee futex: Nullify robust lists after cleanup
The robust list pointers of user space held futexes are kept intact
over an exec() call. When the exec'ed task exits exit_robust_list() is
called with the stale pointer. The risk of corruption is minimal, but
still it is incorrect to keep the pointers valid. Actually glibc
should uninstall the robust list before calling exec() but we have to
deal with it anyway.

Nullify the pointers after [compat_]exit_robust_list() has been
called.

Reported-by: Anirban Sinha <ani@anirban.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Cc: stable@kernel.org
2009-10-06 17:00:01 +02:00
Hiroshi Shimamoto
b0f56f1a63 trace: Fix missing assignment in trace_ctxwake_*
The state char variable S should be reassigned, if S == 0.

We are missing the state of the task that is going to sleep for the
context switch events (in the raw mode).

Fortunately the problem arises with the sched_switch/wake_up
tracers, not the sched trace events.

The formers are legacy now. But still, that was buggy.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4AC43118.6050409@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-06 14:28:24 +02:00
Peter Zijlstra
906010b213 perf_event: Provide vmalloc() based mmap() backing
Some architectures such as Sparc, ARM and MIPS (basically
everything with flush_dcache_page()) need to deal with dcache
aliases by carefully placing pages in both kernel and user maps.

These architectures typically have to use vmalloc_user() for this.

However, on other architectures, vmalloc() is not needed and has
the downsides of being more restricted and slower than regular
allocations.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: David Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1254830228.21044.272.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-06 14:21:50 +02:00
Tom Zanussi
ee949a86b3 tracing/syscalls: Use long for syscall ret format and field definitions
The syscall event definitions use long for the syscall exit ret
value, but unsigned long for the same thing in the format and field
definitions.  Change them all to long.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: rostedt@goodmis.org
Cc: lizf@cn.fujitsu.com
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1254808849-7829-4-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-06 12:02:34 +02:00
Thomas Gleixner
eaaea8036d futex: Fix locking imbalance
Rich reported a lock imbalance in the futex code:

   http://bugzilla.kernel.org/show_bug.cgi?id=14288

It's caused by the displacement of the retry_private label in
futex_wake_op(). The code unlocks the hash bucket locks in the
error handling path and retries without locking them again which
makes the next unlock fail.

Move retry_private so we lock the hash bucket locks when we retry.

Reported-by: Rich Ercolany <rercola@acm.jhu.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Darren Hart <dvhltc@us.ibm.com>
Cc: stable-2.6.31 <stable@kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:08:14 +02:00
Aaro Koskinen
d014e8894d panic: Fix panic message visibility by calling bust_spinlocks(0) before dying
Commit ffd71da4e3 ("panic: decrease oops_in_progress only after
having done the panic") moved bust_spinlocks(0) to the end of the
function, which in practice is never reached.

As a result console_unblank() is not called, and on some systems
the user may not see the panic message.

Move it back up to before the unblanking.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1254483680-25578-1-git-send-email-aaro.koskinen@nokia.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:08:09 +02:00
Linus Torvalds
41cb6654eb Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf tools: Run generate-cmdlist.sh properly
  perf_event: Clean up perf_event_init_task()
  perf_event: Fix event group handling in __perf_event_sched_*()
  perf timechart: Add a power-only mode
  perf top: Add poll_idle to the skip list
2009-10-05 12:04:41 -07:00
Linus Torvalds
e69a9ac596 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimer: Remove overly verbose "switch to high res mode" message
2009-10-05 12:04:16 -07:00
Linus Torvalds
0f26ec69f0 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  kmemtrace: Fix up tracer registration
  tracing: Fix infinite recursion in ftrace_update_pid_func()
2009-10-05 12:03:43 -07:00
Paul E. McKenney
135c8aea55 rcu: Replace the rcu_barrier enum with pointer to call_rcu*() function
The rcu_barrier enum causes several problems:

  (1) you have to define the enum somewhere, and there is no
      convenient place,

  (2) the difference between TREE_RCU and TREE_PREEMPT_RCU causes
      problems when you need to map from rcu_barrier enum to struct
      rcu_state,

  (3) the switch statement are large, and

  (4) TINY_RCU really needs a different rcu_barrier() than do the
      treercu implementations.

So replace it with a functionally equivalent but cleaner function
pointer abstraction.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
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: <12541998232366-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:02:05 +02:00
Paul E. McKenney
a0b6c9a78c rcu: Clean up code based on review feedback from Josh Triplett, part 4
These issues identified during an old-fashioned face-to-face code
review extending over many hours.  This group improves an existing
abstraction and introduces two new ones.  It also fixes an RCU
stall-warning bug found while making the other changes.

o	Make RCU_INIT_FLAVOR() declare its own variables, removing
	the need to declare them at each call site.

o	Create an rcu_for_each_leaf() macro that scans the leaf
	nodes of the rcu_node tree.

o	Create an rcu_for_each_node_breadth_first() macro that does
	a breadth-first traversal of the rcu_node tree, AKA
	stepping through the array in index-number order.

o	If all CPUs corresponding to a given leaf rcu_node
	structure go offline, then any tasks queued on that leaf
	will be moved to the root rcu_node structure.  Therefore,
	the stall-warning code must dump out tasks queued on the
	root rcu_node structure as well as those queued on the leaf
	rcu_node structures.

Signed-off-by: Paul 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: <12541491934126-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:02:04 +02:00
Paul E. McKenney
3d76c08290 rcu: Clean up code based on review feedback from Josh Triplett, part 3
Whitespace fixes, updated comments, and trivial code movement.

o	Fix whitespace error in RCU_HEAD_INIT()

o	Move "So where is rcu_write_lock()" comment so that it does
	not come between the rcu_read_unlock() header comment and
	the rcu_read_unlock() definition.

o	Move the module_param statements for blimit, qhimark, and
	qlowmark to immediately follow the corresponding
	definitions.

o	In __rcu_offline_cpu(), move the assignment to rdp_me
	inside the "if" statement, given that rdp_me is not used
	outside of that "if" statement.

Signed-off-by: Paul 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: <12541491931164-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:02:02 +02:00
Paul E. McKenney
162cc2794d rcu: Fix rcu_lock_map build failure on CONFIG_PROVE_LOCKING=y
Move the rcu_lock_map definition from rcutree.c to rcupdate.c so that
TINY_RCU can use lockdep.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 21:01:28 +02:00
Peter Williams
f83f9ac263 sched: Set correct normal_prio and prio values in sched_fork()
normal_prio should be updated if policy changes from RT to
SCHED_MORMAL or if static_prio/nice is changed.

Some paths through sched_fork() ignore this requirement and may
result in normal_prio having an invalid value.

Fixing this issue allows the call to effective_prio() in
wake_up_new_task() to be removed.

Signed-off-by: Peter Williams <pwil3058@bigpond.net.au>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <f8f46736fd4e7f090ac0.1253774830@mudlark.pw.nest>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-05 13:42:20 +02:00
Frederic Weisbecker
75fb4090b3 tracing: Use free_percpu instead of kfree
In the event->profile_enable() failure path, we release the per cpu
buffers using kfree which is wrong because they are per cpu pointers.
Although free_percpu only wraps kfree for now, that may change in the
future so lets use the correct way.

Reported-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2009-10-05 10:57:56 +02:00
Frederic Weisbecker
fe8e5b5a60 tracing: Check total refcount before releasing bufs in profile_enable failure
When we call the profile_enable() callback of an event, we release the
shared perf event tracing buffers unconditionnaly in the failure path.
This is wrong because there may be other users of these. Then check the
total refcount before doing this.

Reported-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2009-10-05 10:57:41 +02:00
Linus Torvalds
58e57fbd1c Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (41 commits)
  Revert "Seperate read and write statistics of in_flight requests"
  cfq-iosched: don't delay async queue if it hasn't dispatched at all
  block: Topology ioctls
  cfq-iosched: use assigned slice sync value, not default
  cfq-iosched: rename 'desktop' sysfs entry to 'low_latency'
  cfq-iosched: implement slower async initiate and queue ramp up
  cfq-iosched: delay async IO dispatch, if sync IO was just done
  cfq-iosched: add a knob for desktop interactiveness
  Add a tracepoint for block request remapping
  block: allow large discard requests
  block: use normal I/O path for discard requests
  swapfile: avoid NULL pointer dereference in swapon when s_bdev is NULL
  fs/bio.c: move EXPORT* macros to line after function
  Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs
  cciss: fix build when !PROC_FS
  block: Do not clamp max_hw_sectors for stacking devices
  block: Set max_sectors correctly for stacking devices
  cciss: cciss_host_attr_groups should be const
  cciss: Dynamically allocate the drive_info_struct for each logical drive.
  cciss: Add usage_count attribute to each logical drive in /sys
  ...
2009-10-04 12:39:14 -07:00
Andi Kleen
1087e9b4ff HWPOISON: Clean up PR_MCE_KILL interface
While writing the manpage I noticed some shortcomings in the
current interface.

- Define symbolic names for all the different values
- Boundary check the kill mode values
- For symmetry add a get interface too. This allows library
code to get/set the current state.
- For consistency define a PR_MCE_KILL_DEFAULT value

Signed-off-by: Andi Kleen <ak@linux.intel.com>
2009-10-04 03:23:17 +02:00
KAMEZAWA Hiroyuki
4e649152cb memcg: some modification to softlimit under hierarchical memory reclaim.
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: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: KAMEZAWA 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:13 -07:00
KAMEZAWA Hiroyuki
3dece8347d cgroup: catch bad css refcnt at css_put
__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: KAMEZAWA 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:12 -07:00
Alexey Dobriyan
828c09509b const: constify remaining file_operations
[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Paul Mundt
3ae91c21dd module: fix up CONFIG_KALLSYMS=n build.
Starting from commit 4a4962263f "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: Paul Mundt <lethal@linux-sh.org>
Acked-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Jun'ichi Nomura
b0da3f0dad Add a tracepoint for block request remapping
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: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'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: Jens Axboe <jens.axboe@oracle.com>
2009-10-01 21:19:34 +02:00
Zdenek Kabelac
48c0d4d4c0 Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs
Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs
introduced in commit 1d54ad6da9.
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: Zdenek Kabelac <zkabelac@redhat.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-01 21:15:46 +02:00
Paul Mundt
f9ac5a69ed kmemtrace: Fix up tracer registration
Commit ddc1637af2 ("kmemtrace: Print
binary output only if 'bin' option is set") ended up inverting the
error detection logic. register_tracer() returns 0 on success,
which this change caused to treat as an error, resulting in:

[    0.132000] Warning: could not register the kmem tracer

as well as bailing out of the initcall with an error value. This
restores the old logic.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <20090928075540.GD6668@linux-sh.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-01 11:53:44 +02:00
Xiao Guangrong
27f9994c50 perf_event: Clean up perf_event_init_task()
While at it: we can traverse ctx->group_list to get all
group leader, it should be safe since we hold ctx->mutex.

Changlog v1->v2:

  - remove WARN_ON_ONCE() according to Peter Zijlstra's suggestion

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4ABC5AF9.6060808@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-01 09:30:44 +02:00
Xiao Guangrong
8c9ed8e14c perf_event: Fix event group handling in __perf_event_sched_*()
Paul Mackerras says:

 "Actually, looking at this more closely, it has to be a group
 leader anyway since it's at the top level of ctx->group_list.  In
 fact I see four places where we do:

  list_for_each_entry(event, &ctx->group_list, group_entry) {
	if (event == event->group_leader)
		...

 or the equivalent, three of which appear to have been introduced
 by afedadf2 ("perf_counter: Optimize sched in/out of counters")
 back in May by Peter Z.

 As far as I can see the if () is superfluous in each case (a
 singleton event will be a group of 1 and will have its
 group_leader pointing to itself)."

 [ See: http://marc.info/?l=linux-kernel&m=125361238901442&w=2 ]

And Peter Zijlstra points out this is a bugfix:

 "The intent was to call event_sched_{in,out}() for single event
  groups because that's cheaper than group_sched_{in,out}(),
  however..

  - as you noticed, I got the condition wrong, it should have read:

      list_empty(&event->sibling_list)

  - it failed to call group_can_go_on() which deals with ->exclusive.

  - it also doesn't call hw_perf_group_sched_in() which might break
    power."

 [ See: http://marc.info/?l=linux-kernel&m=125369523318583&w=2 ]

Changelog v1->v2:

 - Fix the title name according to Peter Zijlstra's suggestion

 - Remove the comments and WARN_ON_ONCE() as Peter Zijlstra's
   suggestion

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <4ABC5A55.7000208@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-01 09:30:44 +02:00
Matt Fleming
33974093c0 tracing: Fix infinite recursion in ftrace_update_pid_func()
When CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST is enabled
__ftrace_trace_function contains the current trace function, not
ftrace_trace_function.

In ftrace_update_pid_func() we currently incorrectly assign the
value of ftrace_trace_function to __ftrace_trace_funcion before
returning.

Without this patch it is possible to execute an infinite recursion
whereby ftrace_test_stop_func() calls __ftrace_trace_function,
which was assigned ftrace_test_stop_func() in
ftrace_update_pid_func().

Signed-off-by: Matt Fleming <matthew.fleming@imgtec.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1254152581-18347-1-git-send-email-matt@console-pimps.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-01 08:19:24 +02:00
Eric Dumazet
152f9d0710 sched_clock: Fix atomicity/continuity bug by using cmpxchg64()
Commit def0a9b257 (sched_clock: Make it NMI safe) assumed
cmpxchg() of 64bit values was available on X86_32.

That is not so - and causes some subtle scheduler misbehavior due
to incorrect timestamps off to up by ~4 seconds.

Two symptoms are known right now:

 - interactivity problems seen by Arjan: up to 600 msecs
   latencies instead of the expected 20-40 msecs. These
   latencies are very visible on the desktop.

 - incorrect CPU stats: occasionally too high percentages in 'top',
   and crazy CPU usage stats.

Reported-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090930170754.0886ff2e@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-30 22:56:10 +02:00
Alexey Dobriyan
f0f37e2f77 const: mark struct vm_struct_operations
* mark struct vm_area_struct::vm_ops as const
* mark vm_ops in AGP code

But leave TTM code alone, something is fishy there with global vm_ops
being used.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-27 11:39:25 -07:00
Linus Torvalds
6f5071020d Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimer: Eliminate needless reprogramming of clock events device
2009-09-27 10:39:04 -07:00
Linus Torvalds
3b383767c4 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  futex: Add memory barrier commentary to futex_wait_queue_me()
  futex: Fix wakeup race by setting TASK_INTERRUPTIBLE before queue_me()
  futex: Correct futex_q woken state commentary
  futex: Make function kernel-doc commentary consistent
  futex: Correct queue_me and unqueue_me commentary
  futex: Correct futex_wait_requeue_pi() commentary
2009-09-26 10:15:53 -07:00
Linus Torvalds
179b9145d5 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  clocksource: Resume clocksource without taking the clocksource mutex
2009-09-26 10:14:41 -07:00
Linus Torvalds
4187e7e9f1 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  modules, tracing: Remove stale struct marker signature from module_layout()
  tracing/workqueue: Use %pf in workqueue trace events
  tracing: Fix a comment and a trivial format issue in tracepoint.h
  tracing: Fix failure path in ftrace_regex_open()
  tracing: Fix failure path in ftrace_graph_write()
  tracing: Check the return value of trace_get_user()
  tracing: Fix off-by-one in trace_get_user()
2009-09-26 10:13:54 -07:00
Roland Dreier
d3f6302e7e hrtimer: Remove overly verbose "switch to high res mode" message
On big systems, printing <number of CPUs> copies of

    Switched to high resolution mode on CPU nnn

clutters up the kernel log for minimal gain.  Just get rid of them.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
LKML-Reference: <ada1vlw126s.fsf_-_@cisco.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-26 16:58:09 +02:00
David S. Miller
8b3f6af863 Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts:
	drivers/staging/Kconfig
	drivers/staging/Makefile
	drivers/staging/cpc-usb/TODO
	drivers/staging/cpc-usb/cpc-usb_drv.c
	drivers/staging/cpc-usb/cpc.h
	drivers/staging/cpc-usb/cpc_int.h
	drivers/staging/cpc-usb/cpcusb.h
2009-09-24 15:13:11 -07:00
Martin Schwidefsky
89133f9350 clocksource: Resume clocksource without taking the clocksource mutex
git commit 75c5158f70 converted the clocksource spinlock to a
mutex. This causes the following BUG:

BUG: sleeping function called from invalid context at
kernel/mutex.c:280 in_atomic(): 0, irqs_disabled(): 1, pid: 2473,
name: pm-suspend 2 locks held by pm-suspend/2473:
 #0:  (&buffer->mutex){......}, at: [<ffffffff8115ab13>]
sysfs_write_file+0x3c/0x137
 #1:  (pm_mutex){......}, at: [<ffffffff810865b5>]
enter_state+0x39/0x130 Pid: 2473, comm: pm-suspend Not tainted 2.6.31
#1 Call Trace:
 [<ffffffff810792f0>] ? __debug_show_held_locks+0x22/0x24
 [<ffffffff8104a2ef>] __might_sleep+0x107/0x10b
 [<ffffffff8141fca9>] mutex_lock_nested+0x25/0x43
 [<ffffffff81073537>] clocksource_resume+0x1c/0x60
 [<ffffffff81072902>] timekeeping_resume+0x1e/0x1c8
 [<ffffffff812aee62>] __sysdev_resume+0x25/0xcf
 [<ffffffff812aef79>] sysdev_resume+0x6d/0xae
 [<ffffffff810864f8>] suspend_devices_and_enter+0x12b/0x1af
 [<ffffffff8108665b>] enter_state+0xdf/0x130
 [<ffffffff81085dc3>] state_store+0xb6/0xd3
 [<ffffffff81204c73>] kobj_attr_store+0x17/0x19
 [<ffffffff8115abd2>] sysfs_write_file+0xfb/0x137
 [<ffffffff811057d2>] vfs_write+0xae/0x10b
 [<ffffffff81208392>] ? __up_read+0x1a/0x7f
 [<ffffffff811058ef>] sys_write+0x4a/0x6e
 [<ffffffff81011b82>] system_call_fastpath+0x16/0x1b

clocksource_resume is called early in the resume process, there is
only one cpu, no processes are running and the interrupts are
disabled. It is therefore possible to resume the clocksources
without taking the clocksource mutex.

Reported-by: Xiaotian Feng <xtfeng@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Tested-by: Michal Schmidt <mschmidt@redhat.com>
Cc: Xiaotian Feng <xtfeng@gmail.com>
Cc: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <20090924172952.49697825@mschwide.boeblingen.de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-24 22:37:53 +02:00
Darren Hart
9beba3c54d futex: Add memory barrier commentary to futex_wait_queue_me()
The memory barrier semantics of futex_wait_queue_me() are
non-obvious. Add some commentary to try and clarify it.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Dinakar Guniguntala <dino@in.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <20090924185447.694.38948.stgit@Aeon>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-24 22:30:10 +02:00
Linus Torvalds
a6b49cb210 Merge branch 'for-linus' of git://git.monstr.eu/linux-2.6-microblaze
* 'for-linus' of git://git.monstr.eu/linux-2.6-microblaze: (24 commits)
  microblaze: Disable heartbeat/enable emaclite in defconfigs
  microblaze: Support simpleImage.dts make target
  microblaze: Fix _start symbol to physical address
  microblaze: Use LOAD_OFFSET macro to get correct LMA for all sections
  microblaze: Create the LOAD_OFFSET macro used to compute VMA vs LMA offsets
  microblaze: Copy ppc asm-compat.h for clean handling of constants in asm and C
  microblaze: Actually show KiB rather than pages in "Freeing initrd memory:"
  microblaze: Support ptrace syscall tracing.
  microblaze: Updated CPU version and FPGA family codes in PVR
  microblaze: Generate correct signal and siginfo for integer div-by-zero
  microblaze: Don't be noisy when userspace causes hardware exceptions
  microblaze: Remove ipc.h file which points to non-existing asm-generic file
  microblaze: Clear sticky FSR register after generating exception signals
  microblaze: Ensure CPU usermode is set on new userspace processes
  microblaze: Use correct kbuild variable KBUILD_CFLAGS
  microblaze: Save and restore msr in hw exception
  microblaze: Add architectural support for USB EHCI host controllers
  microblaze: Implement include/asm/syscall.h.
  microblaze: Improve checking mechanism for MSR instruction
  microblaze: Add checking mechanism for MSR instruction
  ...
2009-09-24 09:01:44 -07:00
Linus Torvalds
2c9871de0a Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  module: don't call percpu_modfree on NULL pointer.
  module: fix memory leak when load fails after srcversion/version allocated
  module: preferred way to use MODULE_AUTHOR
  param: allow whitespace as kernel parameter separator
  module: reduce string table for loaded modules (v2)
  module: reduce symbol table for loaded modules (v2)
2009-09-24 09:01:05 -07:00
Linus Torvalds
6d39b27f0a Merge git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  lsm: Use a compressed IPv6 string format in audit events
  Audit: send signal info if selinux is disabled
  Audit: rearrange audit_context to save 16 bytes per struct
  Audit: reorganize struct audit_watch to save 8 bytes
2009-09-24 08:31:04 -07:00
Rusty Russell
ffa9f12a41 module: don't call percpu_modfree on NULL pointer.
The general one handles NULL, the static obsolescent
(CONFIG_HAVE_LEGACY_PER_CPU_AREA) one in module.c doesn't; Eric's
commit 720eba31 assumed it did, and various frobbings since then kept
that assumption.

All other callers in module.c all protect it with an if; this effectively
does the same as free_init is only goto if we fail percpu_modalloc().

Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Américo Wang <xiyou.wangcong@gmail.com>
Tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
2009-09-25 00:32:59 +09:30
Rusty Russell
a263f7763c module: fix memory leak when load fails after srcversion/version allocated
Normally the twisty paths of sysfs will free the attributes, but not if
we fail before we hook it into sysfs (which is the last thing we do in
load_module).

(This sysfs code is a turd, no doubt there are other issues lurking too).

Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
2009-09-25 00:32:59 +09:30
Peter Oberparleiter
26d052bfce param: allow whitespace as kernel parameter separator
Some boot mechanisms require that kernel parameters are stored in a
separate file which is loaded to memory without further processing
(e.g. the "Load from FTP" method on s390). When such a file contains
newline characters, the kernel parameter preceding the newline might
not be correctly parsed (due to the newline being stuck to the end of
the actual parameter value) which can lead to boot failures.

This patch improves kernel command line usability in such a situation
by allowing generic whitespace characters as separators between kernel
parameters.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-25 00:32:58 +09:30
Jan Beulich
554bdfe5ac module: reduce string table for loaded modules (v2)
Also remove all parts of the string table (referenced by the symbol
table) that are not needed for kallsyms use (i.e. which were only
referenced by symbols discarded by the previous patch, or not
referenced at all for whatever reason).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-25 00:32:57 +09:30
Jan Beulich
4a4962263f module: reduce symbol table for loaded modules (v2)
Discard all symbols not interesting for kallsyms use: absolute,
section, and in the common case (!KALLSYMS_ALL) data ones.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-09-25 00:32:57 +09:30
Linus Torvalds
db16826367 Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6
* 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6: (21 commits)
  HWPOISON: Enable error_remove_page on btrfs
  HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs
  HWPOISON: Add madvise() based injector for hardware poisoned pages v4
  HWPOISON: Enable error_remove_page for NFS
  HWPOISON: Enable .remove_error_page for migration aware file systems
  HWPOISON: The high level memory error handler in the VM v7
  HWPOISON: Add PR_MCE_KILL prctl to control early kill behaviour per process
  HWPOISON: shmem: call set_page_dirty() with locked page
  HWPOISON: Define a new error_remove_page address space op for async truncation
  HWPOISON: Add invalidate_inode_page
  HWPOISON: Refactor truncate to allow direct truncating of page v2
  HWPOISON: check and isolate corrupted free pages v2
  HWPOISON: Handle hardware poisoned pages in try_to_unmap
  HWPOISON: Use bitmask/action code for try_to_unmap behaviour
  HWPOISON: x86: Add VM_FAULT_HWPOISON handling to x86 page fault handler v2
  HWPOISON: Add poison check to page fault handling
  HWPOISON: Add basic support for poisoned pages in fault handler v3
  HWPOISON: Add new SIGBUS error codes for hardware poison signals
  HWPOISON: Add support for poison swap entries v2
  HWPOISON: Export some rmap vma locking to outside world
  ...
2009-09-24 07:53:22 -07:00
Hiroshi Shimamoto
801460d0cf task_struct cleanup: move binfmt field to mm_struct
Because the binfmt is not different between threads in the same process,
it can be moved from task_struct to mm_struct.  And binfmt moudle is
handled per mm_struct instead of task_struct.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:05 -07:00
Alexey Dobriyan
858f09930b aio: ifdef fields in mm_struct
->ioctx_lock and ->ioctx_list are used only under CONFIG_AIO.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:05 -07:00
Sukadev Bhattiprolu
e5a4738699 pidns: deny CLONE_PARENT|CLONE_NEWPID combination
CLONE_PARENT was used to implement an older threading model.  For
consistency with the CLONE_THREAD check in copy_pid_ns(), disable
CLONE_PARENT with CLONE_NEWPID, at least until the required semantics of
pid namespaces are clear.

Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Oren Laadan <orenl@cs.columbia.edu>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:04 -07:00
Sukadev Bhattiprolu
123be07b0b fork(): disable CLONE_PARENT for init
When global or container-init processes use CLONE_PARENT, they create a
multi-rooted process tree.  Besides siblings of global init remain as
zombies on exit since they are not reaped by their parent (swapper).  So
prevent global and container-inits from creating siblings.

Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Oren Laadan <orenl@cs.columbia.edu>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:04 -07:00
Alexey Dobriyan
8d65af789f sysctl: remove "struct file *" argument of ->proc_handler
It's unused.

It isn't needed -- read or write flag is already passed and sysctl
shouldn't care about the rest.

It _was_ used in two places at arch/frv for some reason.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:04 -07:00
Roland McGrath
d9588725e5 signals: inline __fatal_signal_pending
__fatal_signal_pending inlines to one instruction on x86, probably two
instructions on other machines.  It takes two longer x86 instructions just
to call it and test its return value, not to mention the function itself.

On my random x86_64 config, this saved 70 bytes of text (59 of those being
__fatal_signal_pending itself).

Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:01 -07:00
Oleg Nesterov
4a30debfb7 signals: introduce do_send_sig_info() helper
Introduce do_send_sig_info() and convert group_send_sig_info(),
send_sig_info(), do_send_specific() to use this helper.

Hopefully it will have more users soon, it allows to specify
specific/group behaviour via "bool group" argument.

Shaves 80 bytes from .text.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:01 -07:00
Neil Horman
a293980c2e exec: let do_coredump() limit the number of concurrent dumps to pipes
Introduce core pipe limiting sysctl.

Since we can dump cores to pipe, rather than directly to the filesystem,
we create a condition in which a user can create a very high load on the
system simply by running bad applications.

If the pipe reader specified in core_pattern is poorly written, we can
have lots of ourstandig resources and processes in the system.

This sysctl introduces an ability to limit that resource consumption.
core_pipe_limit defines how many in-flight dumps may be run in parallel,
dumps beyond this value are skipped and a note is made in the kernel log.
A special value of 0 in core_pipe_limit denotes unlimited core dumps may
be handled (this is the default value).

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Earl Chew <earl_chew@agilent.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Roland McGrath
ae6d2ed7bb signals: tracehook_notify_jctl change
This changes tracehook_notify_jctl() so it's called with the siglock held,
and changes its argument and return value definition.  These clean-ups
make it a better fit for what new tracing hooks need to check.

Tracing needs the siglock here, held from the time TASK_STOPPED was set,
to avoid potential SIGCONT races if it wants to allow any blocking in its
tracing hooks.

This also folds the finish_stop() function into its caller
do_signal_stop().  The function is short, called only once and only
unconditionally.  It aids readability to fold it in.

[oleg@redhat.com: do not call tracehook_notify_jctl() in TASK_STOPPED state]
[oleg@redhat.com: introduce tracehook_finish_jctl() helper]
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Vitaly Mayatskikh
b6fe2d117e wait_noreap_copyout(): check for ->wo_info != NULL
Current behaviour of sys_waitid() looks odd.  If user passes infop ==
NULL, sys_waitid() returns success.  When user additionally specifies flag
WNOWAIT, sys_waitid() returns -EFAULT on the same conditions.  When user
combines WNOWAIT with WCONTINUED, sys_waitid() again returns success.

This patch adds check for ->wo_info in wait_noreap_copyout().

User-visible change: starting from this commit, sys_waitid() always checks
infop != NULL and does not fail if it is NULL.

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Vitaly Mayatskikh
dfe16dfa4a do_wait: fix sys_waitid()-specific behaviour
do_wait() checks ->wo_info to figure out who is the caller.  If it's not
NULL the caller should be sys_waitid(), in that case do_wait() fixes up
the retval or zeros ->wo_info, depending on retval from underlying
function.

This is bug: user can pass ->wo_info == NULL and sys_waitid() will return
incorrect value.

man 2 waitid says:

	waitid(): returns 0 on success

Test-case:

	int main(void)
	{
		if (fork())
			assert(waitid(P_ALL, 0, NULL, WEXITED) == 0);

		return 0;
	}

Result:

	Assertion `waitid(P_ALL, 0, ((void *)0), 4) == 0' failed.

Move that code to sys_waitid().

User-visible change: sys_waitid() will return 0 on success, either
infop is set or not.

Note, there's another bug in wait_noreap_copyout() which affects
return value of sys_waitid(). It will be fixed in next patch.

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Oleg Nesterov
b6e763f07f wait_consider_task: kill "parent" argument
Kill the unused "parent" argument in wait_consider_task(), it was never used.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Oleg Nesterov
989264f464 do_wait-wakeup-optimization: simplify task_pid_type()
task_pid_type() is only used by eligible_pid() which has to check wo_type
!= PIDTYPE_MAX anyway.  Remove this check from task_pid_type() and factor
out ->pids[type] access, this shrinks .text a bit and simplifies the code.

The matches the behaviour of other similar helpers, say get_task_pid().
The caller must ensure that pid_type is valid, not the callee.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Oleg Nesterov
5c01ba49e6 do_wait-wakeup-optimization: fix child_wait_callback()->eligible_child() usage
child_wait_callback()->eligible_child() is not right, we can miss the
wakeup if the task was detached before __wake_up_parent() and the caller
of do_wait() didn't use __WALL.

Move ->wo_pid checks from eligible_child() to the new helper,
eligible_pid(), and change child_wait_callback() to use it instead of
eligible_child().

Note: actually I think it would be better to fix the __WCLONE check in
eligible_child(), it doesn't look exactly right.  But it is not clear what
is the supposed behaviour, and any change is user-visible.

Reported-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Oleg Nesterov
b4fe51823d do_wait() wakeup optimization: child_wait_callback: check __WNOTHREAD case
Suggested by Roland.

do_wait(__WNOTHREAD) can only succeed if the caller is either ptracer, or
it is ->real_parent and the child is not traced. IOW, caller == p->parent
otherwise we should not wake up.

Change child_wait_callback() to check this. Ratan reports the workload with
CPU load >99% caused by unnecessary wakeups, should be fixed by this patch.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:21:00 -07:00
Oleg Nesterov
0b7570e77f do_wait() wakeup optimization: change __wake_up_parent() to use filtered wakeup
Ratan Nalumasu reported that in a process with many threads doing
unnecessary wakeups.  Every waiting thread in the process wakes up to loop
through the children and see that the only ones it cares about are still
not ready.

Now that we have struct wait_opts we can change do_wait/__wake_up_parent
to use filtered wakeups.

We can make child_wait_callback() more clever later, right now it only
checks eligible_child().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:20:59 -07:00
Oleg Nesterov
a2322e1d27 do_wait() wakeup optimization: shift security_task_wait() from eligible_child() to wait_consider_task()
Preparation, no functional changes.

eligible_child() has a single caller, wait_consider_task(). We can move
security_task_wait() out from eligible_child(), this allows us to use it
for filtered wake_up().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:20:59 -07:00
Oleg Nesterov
a7f0765edf ptrace: __ptrace_detach: do __wake_up_parent() if we reap the tracee
The bug is old, it wasn't cause by recent changes.

Test case:

	static void *tfunc(void *arg)
	{
		int pid = (long)arg;

		assert(ptrace(PTRACE_ATTACH, pid, NULL, NULL) == 0);
		kill(pid, SIGKILL);

		sleep(1);
		return NULL;
	}

	int main(void)
	{
		pthread_t th;
		long pid = fork();

		if (!pid)
			pause();

		signal(SIGCHLD, SIG_IGN);
		assert(pthread_create(&th, NULL, tfunc, (void*)pid) == 0);

		int r = waitpid(-1, NULL, __WNOTHREAD);
		printf("waitpid: %d %m\n", r);

		return 0;
	}

Before the patch this program hangs, after this patch waitpid() correctly
fails with errno == -ECHILD.

The problem is, __ptrace_detach() reaps the EXIT_ZOMBIE tracee if its
->real_parent is our sub-thread and we ignore SIGCHLD.  But in this case
we should wake up other threads which can sleep in do_wait().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:20:59 -07:00
Balbir Singh
f64c3f5494 memory controller: soft limit organize cgroups
Organize cgroups over soft limit in a RB-Tree

Introduce an RB-Tree for storing memory cgroups that are over their soft
limit.  The overall goal is to

1. Add a memory cgroup to the RB-Tree when the soft limit is exceeded.
   We are careful about updates, updates take place only after a particular
   time interval has passed
2. We remove the node from the RB-Tree when the usage goes below the soft
   limit

The next set of patches will exploit the RB-Tree to get the group that is
over its soft limit by the largest amount and reclaim from it, when we
face memory contention.

[hugh.dickins@tiscali.co.uk: CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_PREEMPT=y fails to boot]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24 07:20:59 -07:00