Commit Graph

17807 Commits

Author SHA1 Message Date
Linus Torvalds 462bf234a8 Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core locking updates from Ingo Molnar:
 "The biggest change is the MCS spinlock generalization changes from Tim
  Chen, Peter Zijlstra, Jason Low et al.  There's also lockdep
  fixes/enhancements from Oleg Nesterov, in particular a false negative
  fix related to lockdep_set_novalidate_class() usage"

* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  locking/mutex: Fix debug checks
  locking/mutexes: Add extra reschedule point
  locking/mutexes: Introduce cancelable MCS lock for adaptive spinning
  locking/mutexes: Unlock the mutex without the wait_lock
  locking/mutexes: Modify the way optimistic spinners are queued
  locking/mutexes: Return false if task need_resched() in mutex_can_spin_on_owner()
  locking: Move mcs_spinlock.h into kernel/locking/
  m68k: Skip futex_atomic_cmpxchg_inatomic() test
  futex: Allow architectures to skip futex_atomic_cmpxchg_inatomic() test
  Revert "sched/wait: Suppress Sparse 'variable shadowing' warning"
  lockdep: Change lockdep_set_novalidate_class() to use _and_name
  lockdep: Change mark_held_locks() to check hlock->check instead of lockdep_no_validate
  lockdep: Don't create the wrong dependency on hlock->check == 0
  lockdep: Make held_lock->check and "int check" argument bool
  locking/mcs: Allow architecture specific asm files to be used for contended case
  locking/mcs: Order the header files in Kbuild of each architecture in alphabetical order
  sched/wait: Suppress Sparse 'variable shadowing' warning
  hung_task/Documentation: Fix hung_task_warnings description
  locking/mcs: Allow architectures to hook in to contended paths
  locking/mcs: Micro-optimize the MCS code, add extra comments
  ...
2014-03-31 10:59:39 -07:00
Alexei Starovoitov bd4cf0ed33 net: filter: rework/optimize internal BPF interpreter's instruction set
This patch replaces/reworks the kernel-internal BPF interpreter with
an optimized BPF instruction set format that is modelled closer to
mimic native instruction sets and is designed to be JITed with one to
one mapping. Thus, the new interpreter is noticeably faster than the
current implementation of sk_run_filter(); mainly for two reasons:

1. Fall-through jumps:

  BPF jump instructions are forced to go either 'true' or 'false'
  branch which causes branch-miss penalty. The new BPF jump
  instructions have only one branch and fall-through otherwise,
  which fits the CPU branch predictor logic better. `perf stat`
  shows drastic difference for branch-misses between the old and
  new code.

2. Jump-threaded implementation of interpreter vs switch
   statement:

  Instead of single table-jump at the top of 'switch' statement,
  gcc will now generate multiple table-jump instructions, which
  helps CPU branch predictor logic.

Note that the verification of filters is still being done through
sk_chk_filter() in classical BPF format, so filters from user- or
kernel space are verified in the same way as we do now, and same
restrictions/constraints hold as well.

We reuse current BPF JIT compilers in a way that this upgrade would
even be fine as is, but nevertheless allows for a successive upgrade
of BPF JIT compilers to the new format.

The internal instruction set migration is being done after the
probing for JIT compilation, so in case JIT compilers are able to
create a native opcode image, we're going to use that, and in all
other cases we're doing a follow-up migration of the BPF program's
instruction set, so that it can be transparently run in the new
interpreter.

In short, the *internal* format extends BPF in the following way (more
details can be taken from the appended documentation):

  - Number of registers increase from 2 to 10
  - Register width increases from 32-bit to 64-bit
  - Conditional jt/jf targets replaced with jt/fall-through
  - Adds signed > and >= insns
  - 16 4-byte stack slots for register spill-fill replaced
    with up to 512 bytes of multi-use stack space
  - Introduction of bpf_call insn and register passing convention
    for zero overhead calls from/to other kernel functions
  - Adds arithmetic right shift and endianness conversion insns
  - Adds atomic_add insn
  - Old tax/txa insns are replaced with 'mov dst,src' insn

Performance of two BPF filters generated by libpcap resp. bpf_asm
was measured on x86_64, i386 and arm32 (other libpcap programs
have similar performance differences):

fprog #1 is taken from Documentation/networking/filter.txt:
tcpdump -i eth0 port 22 -dd

fprog #2 is taken from 'man tcpdump':
tcpdump -i eth0 'tcp port 22 and (((ip[2:2] - ((ip[0]&0xf)<<2)) -
   ((tcp[12]&0xf0)>>2)) != 0)' -dd

Raw performance data from BPF micro-benchmark: SK_RUN_FILTER on the
same SKB (cache-hit) or 10k SKBs (cache-miss); time in ns per call,
smaller is better:

--x86_64--
         fprog #1  fprog #1   fprog #2  fprog #2
         cache-hit cache-miss cache-hit cache-miss
old BPF      90       101        192       202
new BPF      31        71         47        97
old BPF jit  12        34         17        44
new BPF jit TBD

--i386--
         fprog #1  fprog #1   fprog #2  fprog #2
         cache-hit cache-miss cache-hit cache-miss
old BPF     107       136        227       252
new BPF      40       119         69       172

--arm32--
         fprog #1  fprog #1   fprog #2  fprog #2
         cache-hit cache-miss cache-hit cache-miss
old BPF     202       300        475       540
new BPF     180       270        330       470
old BPF jit  26       182         37       202
new BPF jit TBD

Thus, without changing any userland BPF filters, applications on
top of AF_PACKET (or other families) such as libpcap/tcpdump, cls_bpf
classifier, netfilter's xt_bpf, team driver's load-balancing mode,
and many more will have better interpreter filtering performance.

While we are replacing the internal BPF interpreter, we also need
to convert seccomp BPF in the same step to make use of the new
internal structure since it makes use of lower-level API details
without being further decoupled through higher-level calls like
sk_unattached_filter_{create,destroy}(), for example.

Just as for normal socket filtering, also seccomp BPF experiences
a time-to-verdict speedup:

05-sim-long_jumps.c of libseccomp was used as micro-benchmark:

  seccomp_rule_add_exact(ctx,...
  seccomp_rule_add_exact(ctx,...

  rc = seccomp_load(ctx);

  for (i = 0; i < 10000000; i++)
     syscall(199, 100);

'short filter' has 2 rules
'large filter' has 200 rules

'short filter' performance is slightly better on x86_64/i386/arm32
'large filter' is much faster on x86_64 and i386 and shows no
               difference on arm32

--x86_64-- short filter
old BPF: 2.7 sec
 39.12%  bench  libc-2.15.so       [.] syscall
  8.10%  bench  [kernel.kallsyms]  [k] sk_run_filter
  6.31%  bench  [kernel.kallsyms]  [k] system_call
  5.59%  bench  [kernel.kallsyms]  [k] trace_hardirqs_on_caller
  4.37%  bench  [kernel.kallsyms]  [k] trace_hardirqs_off_caller
  3.70%  bench  [kernel.kallsyms]  [k] __secure_computing
  3.67%  bench  [kernel.kallsyms]  [k] lock_is_held
  3.03%  bench  [kernel.kallsyms]  [k] seccomp_bpf_load
new BPF: 2.58 sec
 42.05%  bench  libc-2.15.so       [.] syscall
  6.91%  bench  [kernel.kallsyms]  [k] system_call
  6.25%  bench  [kernel.kallsyms]  [k] trace_hardirqs_on_caller
  6.07%  bench  [kernel.kallsyms]  [k] __secure_computing
  5.08%  bench  [kernel.kallsyms]  [k] sk_run_filter_int_seccomp

--arm32-- short filter
old BPF: 4.0 sec
 39.92%  bench  [kernel.kallsyms]  [k] vector_swi
 16.60%  bench  [kernel.kallsyms]  [k] sk_run_filter
 14.66%  bench  libc-2.17.so       [.] syscall
  5.42%  bench  [kernel.kallsyms]  [k] seccomp_bpf_load
  5.10%  bench  [kernel.kallsyms]  [k] __secure_computing
new BPF: 3.7 sec
 35.93%  bench  [kernel.kallsyms]  [k] vector_swi
 21.89%  bench  libc-2.17.so       [.] syscall
 13.45%  bench  [kernel.kallsyms]  [k] sk_run_filter_int_seccomp
  6.25%  bench  [kernel.kallsyms]  [k] __secure_computing
  3.96%  bench  [kernel.kallsyms]  [k] syscall_trace_exit

--x86_64-- large filter
old BPF: 8.6 seconds
    73.38%    bench  [kernel.kallsyms]  [k] sk_run_filter
    10.70%    bench  libc-2.15.so       [.] syscall
     5.09%    bench  [kernel.kallsyms]  [k] seccomp_bpf_load
     1.97%    bench  [kernel.kallsyms]  [k] system_call
new BPF: 5.7 seconds
    66.20%    bench  [kernel.kallsyms]  [k] sk_run_filter_int_seccomp
    16.75%    bench  libc-2.15.so       [.] syscall
     3.31%    bench  [kernel.kallsyms]  [k] system_call
     2.88%    bench  [kernel.kallsyms]  [k] __secure_computing

--i386-- large filter
old BPF: 5.4 sec
new BPF: 3.8 sec

--arm32-- large filter
old BPF: 13.5 sec
 73.88%  bench  [kernel.kallsyms]  [k] sk_run_filter
 10.29%  bench  [kernel.kallsyms]  [k] vector_swi
  6.46%  bench  libc-2.17.so       [.] syscall
  2.94%  bench  [kernel.kallsyms]  [k] seccomp_bpf_load
  1.19%  bench  [kernel.kallsyms]  [k] __secure_computing
  0.87%  bench  [kernel.kallsyms]  [k] sys_getuid
new BPF: 13.5 sec
 76.08%  bench  [kernel.kallsyms]  [k] sk_run_filter_int_seccomp
 10.98%  bench  [kernel.kallsyms]  [k] vector_swi
  5.87%  bench  libc-2.17.so       [.] syscall
  1.77%  bench  [kernel.kallsyms]  [k] __secure_computing
  0.93%  bench  [kernel.kallsyms]  [k] sys_getuid

BPF filters generated by seccomp are very branchy, so the new
internal BPF performance is better than the old one. Performance
gains will be even higher when BPF JIT is committed for the
new structure, which is planned in future work (as successive
JIT migrations).

BPF has also been stress-tested with trinity's BPF fuzzer.

Joint work with Daniel Borkmann.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Paul Moore <pmoore@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: linux-kernel@vger.kernel.org
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-31 00:45:09 -04:00
Rusty Russell 57673c2b0b Use 'E' instead of 'X' for unsigned module taint flag.
Takashi Iwai <tiwai@suse.de> says:
> The letter 'X' has been already used for SUSE kernels for very long
> time, to indicate the external supported modules.  Can the new flag be
> changed to another letter for avoiding conflict...?
> (BTW, we also use 'N' for "no support", too.)

Note: this code should be cleaned up, so we don't have such maps in
three places!

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-03-31 14:52:43 +10:30
Eric Paris aa4af831bb AUDIT: Allow login in non-init namespaces
It its possible to configure your PAM stack to refuse login if audit
messages (about the login) were unable to be sent.  This is common in
many distros and thus normal configuration of many containers.  The PAM
modules determine if audit is enabled/disabled in the kernel based on
the return value from sending an audit message on the netlink socket.
If userspace gets back ECONNREFUSED it believes audit is disabled in the
kernel.  If it gets any other error else it refuses to let the login
proceed.

Just about ever since the introduction of namespaces the kernel audit
subsystem has returned EPERM if the task sending a message was not in
the init user or pid namespace.  So many forms of containers have never
worked if audit was enabled in the kernel.

BUT if the container was not in net_init then the kernel network code
would send ECONNREFUSED (instead of the audit code sending EPERM).  Thus
by pure accident/dumb luck/bug if an admin configured the PAM stack to
reject all logins that didn't talk to audit, but then ran the login
untility in the non-init_net namespace, it would work!! Clearly this was
a bug, but it is a bug some people expected.

With the introduction of network namespace support in 3.14-rc1 the two
bugs stopped cancelling each other out.  Now, containers in the
non-init_net namespace refused to let users log in (just like PAM was
configfured!) Obviously some people were not happy that what used to let
users log in, now didn't!

This fix is kinda hacky.  We return ECONNREFUSED for all non-init
relevant namespaces.  That means that not only will the old broken
non-init_net setups continue to work, now the broken non-init_pid or
non-init_user setups will 'work'.  They don't really work, since audit
isn't logging things.  But it's what most users want.

In 3.15 we should have patches to support not only the non-init_net
(3.14) namespace but also the non-init_pid and non-init_user namespace.
So all will be right in the world.  This just opens the doors wide open
on 3.14 and hopefully makes users happy, if not the audit system...

Reported-by: Andre Tomt <andre@tomt.net>
Reported-by: Adam Richter <adam_richter2004@yahoo.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-30 17:02:53 -07:00
Li Zefan 1ec41830e0 cgroup: remove useless argument from cgroup_exit()
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-29 09:15:54 -04:00
Li Zefan e8604cb436 cgroup: fix spurious lockdep warning in cgroup_exit()
cgroup_exit() is called in fork and exit path. If it's called in the
failure path during fork, PF_EXITING isn't set, and then lockdep will
complain.

Fix this by removing cgroup_exit() in that failure path. cgroup_fork()
does nothing that needs cleanup.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-29 09:15:53 -04:00
John Stultz cab5e127ee time: Revert to calling clock_was_set_delayed() while in irq context
In commit 47a1b79630 ("tick/timekeeping: Call
update_wall_time outside the jiffies lock"), we moved to calling
clock_was_set() due to the fact that we were no longer holding
the timekeeping or jiffies lock.

However, there is still the problem that clock_was_set()
triggers an IPI, which cannot be done from the timer's hard irq
context, and will generate WARN_ON warnings.

Apparently in my earlier testing, I'm guessing I didn't bump the
dmesg log level, so I somehow missed the WARN_ONs.

Thus we need to revert back to calling clock_was_set_delayed().

Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1395963049-11923-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-28 08:07:07 +01:00
Linus Torvalds f217c44ebd While on my flight to Linux Collaboration Summit, I was working on
my slides for the event trigger tutorial. I booted a 3.14-rc7 kernel
 to perform what I wanted to teach and cut and paste it into my slides.
 When I tried the traceon event trigger with a condition attached to it
 (turns tracing on only if a field of the trigger event matches a condition
 set by the user), nothing happened. Tracing would not turn on. I stopped
 working on my presentation in order to find what was wrong.
 
 It ended up being the way trace event triggers work when they have
 conditions. Instead of copying the fields, the condition code just
 looks at the fields that were copied into the ring buffer. This works
 great, unless tracing is off. That's because when the event is reserved
 on the ring buffer, the ring buffer returns a NULL pointer, this tells
 the tracing code that the ring buffer is disabled. This ends up being
 a problem for the traceon trigger if it is using this information to
 check its condition.
 
 Luckily the code that checks if tracing is on returns the ring buffer
 to use (because the ring buffer is determined by the event file
 also passed to that field). I was able to easily solve this bug by
 checking in that helper function if the returned ring buffer entry
 is NULL, and if so, also check the file flag if it has a trace event
 trigger condition, and if so, to pass back a temp ring buffer to use.
 This will allow the trace event trigger condition to still test the
 event fields, but nothing will be recorded.
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Merge tag 'trace-fixes-v3.14-rc7-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "While on my flight to Linux Collaboration Summit, I was working on my
  slides for the event trigger tutorial.  I booted a 3.14-rc7 kernel to
  perform what I wanted to teach and cut and paste it into my slides.
  When I tried the traceon event trigger with a condition attached to it
  (turns tracing on only if a field of the trigger event matches a
  condition set by the user), nothing happened.  Tracing would not turn
  on.  I stopped working on my presentation in order to find what was
  wrong.

  It ended up being the way trace event triggers work when they have
  conditions.  Instead of copying the fields, the condition code just
  looks at the fields that were copied into the ring buffer.  This works
  great, unless tracing is off.  That's because when the event is
  reserved on the ring buffer, the ring buffer returns a NULL pointer,
  this tells the tracing code that the ring buffer is disabled.  This
  ends up being a problem for the traceon trigger if it is using this
  information to check its condition.

  Luckily the code that checks if tracing is on returns the ring buffer
  to use (because the ring buffer is determined by the event file also
  passed to that field).  I was able to easily solve this bug by
  checking in that helper function if the returned ring buffer entry is
  NULL, and if so, also check the file flag if it has a trace event
  trigger condition, and if so, to pass back a temp ring buffer to use.
  This will allow the trace event trigger condition to still test the
  event fields, but nothing will be recorded"

* tag 'trace-fixes-v3.14-rc7-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix traceon trigger condition to actually turn tracing on
2014-03-26 09:09:18 -07:00
Steven Rostedt (Red Hat) 2c4a33aba5 tracing: Fix traceon trigger condition to actually turn tracing on
While working on my tutorial for 2014 Linux Collaboration Summit
I found that the traceon trigger did not work when conditions were
used. The other triggers worked fine though. Looking into it, it
is because of the way the triggers use the ring buffer to store
the fields it will use for the condition. But if tracing is off, nothing
is stored in the buffer, and the tracepoint exits before calling the
trigger to test the condition. This is fine for all the triggers that
only work when tracing is on, but for traceon trigger that is to
work when tracing is off, nothing happens.

The fix is simple, just use a temp ring buffer to record the event
if tracing is off and the event has a trace event conditional trigger
enabled. The rest of the tracepoint code will work just fine, but
the tracepoint wont be recorded in the other buffers.

Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-25 23:39:41 -04:00
Viresh Kumar b97f0291a2 tick: Remove code duplication in tick_handle_periodic()
tick_handle_periodic() is calling ktime_add() at two places, first before the
infinite loop and then at the end of infinite loop. We can rearrange code a bit
to fix code duplication here.

It looks quite simple and shouldn't break anything, I guess :)

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Link: http://lkml.kernel.org/r/be3481e8f3f71df694a4b43623254fc93ca51b59.1395735873.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-26 00:56:49 +01:00
Viresh Kumar cacb3c76c2 tick: Fix spelling mistake in tick_handle_periodic()
One of the comments in tick_handle_periodic() had 'when' instead of 'which' (My
guess :)). Fix it.

Also fix spelling mistake in 'Possible'.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: skarafotis@gmail.com
Link: http://lkml.kernel.org/r/2b29ca4230c163e44179941d7c7a16c1474385c2.1395743878.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-26 00:56:49 +01:00
Thomas Gleixner ea2e64f280 workqueue: Provide destroy_delayed_work_on_stack()
If a delayed or deferrable work is on stack we need to tell debug
objects that we are destroying the timer and the work. Otherwise we
leak the tracking object.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Acked-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20140323141939.911487677@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-25 17:33:42 +01:00
Ingo Molnar 7de700e680 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU update from Paul E. McKenney:

" [...] one late-breaking commit.  This one was requested for 3.15 by Peter Zijlstra.
  It is low risk because it adds a new in-kernel API with minimal changes to the
  existing code.  Those minimal changes are the addition of memory barriers and
  ACCESS_ONCE() macro calls, neither of which should be able to break things.
  This commit has passed significant rcutorture testing, with these additional
  additions to rcutorture slated for 3.16.  This commit has also been exposed to
  -next testing. "

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-25 06:45:39 +01:00
Monam Agarwal e231d54c12 kernel: Use RCU_INIT_POINTER(x, NULL) in audit.c
This patch replaces rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)

The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure.
And in the case of the NULL pointer, there is no structure to initialize.
So, rcu_assign_pointer(p, NULL) can be safely converted to RCU_INIT_POINTER(p, NULL)

Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-24 12:00:22 -04:00
Aaron Tomlin 3862807880 tracing: Add BUG_ON when stack end location is over written
It is difficult to detect a stack overrun when it
actually occurs.

We have observed that this type of corruption is often
silent and can go unnoticed. Once the corrupted region
is examined, the outcome is undefined and often
results in sporadic system crashes.

When the stack tracing feature is enabled, let's check
for this condition and take appropriate action.

Note: init_task doesn't get its stack end location
set to STACK_END_MAGIC.

Link: http://lkml.kernel.org/r/1395669837-30209-1-git-send-email-atomlin@redhat.com

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-24 10:39:11 -04:00
Monam Agarwal 01a9714061 cgroup: Use RCU_INIT_POINTER(x, NULL) in cgroup.c
This patch replaces rcu_assign_pointer(x, NULL) with
RCU_INIT_POINTER(x, NULL)

The rcu_assign_pointer() ensures that the initialization of a
structure is carried out before storing a pointer to that structure.
And in the case of the NULL pointer, there is no structure to
initialize.  So, rcu_assign_pointer(p, NULL) can be safely converted
to RCU_INIT_POINTER(p, NULL)

Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-24 08:48:02 -04:00
Alexander Shiyan d6ee6d2325 genirq: Export symbol no_action()
This will allow to use the dummy IRQ handler no_action() from drivers
compiled as module. Drivers which use ARM FIQ interrupts can use this
to request the interrupt via the normal request_irq() mechanism w/o
having to copy the dummy handler to their own code.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Link: http://lkml.kernel.org/r/1395476431-16070-1-git-send-email-shc_work@mail.ru
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-22 11:33:09 +01:00
Mathieu Desnoyers 0dea6d5263 tracepoint: Remove unused API functions
After the following commit:

commit b75ef8b44b
Author: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date:   Wed Aug 10 15:18:39 2011 -0400

    Tracepoint: Dissociate from module mutex

The following functions became unnecessary:

- tracepoint_probe_register_noupdate,
- tracepoint_probe_unregister_noupdate,
- tracepoint_probe_update_all.

In fact, none of the in-kernel tracers, nor LTTng, nor SystemTAP use
them. Remove those.

Moreover, the functions:

- tracepoint_iter_start,
- tracepoint_iter_next,
- tracepoint_iter_stop,
- tracepoint_iter_reset.

are unused by in-kernel tracers, LTTng and SystemTAP. Remove those too.

Link: http://lkml.kernel.org/r/1395379142-2118-2-git-send-email-mathieu.desnoyers@efficios.com

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-21 14:01:15 -04:00
Steven Rostedt (Red Hat) bc4c426ee2 Revert "tracing: Move event storage for array from macro to standalone function"
I originally wrote commit 35bb4399bd to shrink the size of the overhead of
tracepoints by several kilobytes. Later, I received a patch from Vaibhav
Nagarnaik that fixed a bug in the same code that this commit touches. Not
only did it fix a bug, it also removed code and shrunk the size of the
overhead of trace events even more than this commit did.

Since this commit is scheduled for 3.15 and Vaibhav's patch is already in
mainline, I need to revert this patch in order to keep it from conflicting
with Vaibhav's patch. Not to mention, Vaibhav's patch makes this patch
obsolete.

Link: http://lkml.kernel.org/r/20140320225637.0226041b@gandalf.local.home

Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-21 13:11:41 -04:00
Linus Torvalds 11d4616bd0 futex: revert back to the explicit waiter counting code
Srikar Dronamraju reports that commit b0c29f79ec ("futexes: Avoid
taking the hb->lock if there's nothing to wake up") causes java threads
getting stuck on futexes when runing specjbb on a power7 numa box.

The cause appears to be that the powerpc spinlocks aren't using the same
ticket lock model that we use on x86 (and other) architectures, which in
turn result in the "spin_is_locked()" test in hb_waiters_pending()
occasionally reporting an unlocked spinlock even when there are pending
waiters.

So this reinstates Davidlohr Bueso's original explicit waiter counting
code, which I had convinced Davidlohr to drop in favor of figuring out
the pending waiters by just using the existing state of the spinlock and
the wait queue.

Reported-and-tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Original-code-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-20 22:11:17 -07:00
Linus Torvalds 477cc48484 Vaibhav Nagarnaik discovered that since 3.10 a clean up patch made the
array index in the trace event format bogus. He supplied an elegant solution
 that uses __stringify() and also removes the need for the event_storage
 and event_storage_mutex and also cuts off a few K of overhead from
 the trace events.
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Merge tag 'trace-fixes-v3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull trace fix from Steven Rostedt:
 "Vaibhav Nagarnaik discovered that since 3.10 a clean-up patch made the
  array index in the trace event format bogus.

  He supplied an elegant solution that uses __stringify() and also
  removes the need for the event_storage and event_storage_mutex and
  also cuts off a few K of overhead from the trace events"

* tag 'trace-fixes-v3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix array size mismatch in format string
2014-03-20 22:09:30 -07:00
Paul E. McKenney 765a3f4fed rcu: Provide grace-period piggybacking API
The following pattern is currently not well supported by RCU:

1.	Make data element inaccessible to RCU readers.

2.	Do work that probably lasts for more than one grace period.

3.	Do something to make sure RCU readers in flight before #1 above
	have completed.

Here are some things that could currently be done:

a.	Do a synchronize_rcu() unconditionally at either #1 or #3 above.
	This works, but imposes needless work and latency.

b.	Post an RCU callback at #1 above that does a wakeup, then
	wait for the wakeup at #3.  This works well, but likely results
	in an extra unneeded grace period.  Open-coding this is also
	a bit more semi-tricky code than would be good.

This commit therefore adds get_state_synchronize_rcu() and
cond_synchronize_rcu() APIs.  Call get_state_synchronize_rcu() at #1
above and pass its return value to cond_synchronize_rcu() at #3 above.
This results in a call to synchronize_rcu() if no grace period has
elapsed between #1 and #3, but requires only a load, comparison, and
memory barrier if a full grace period did elapse.

Requested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
2014-03-20 17:12:25 -07:00
Dave Jones 8c90487cdc Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC
Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC, so we can repurpose
the flag to encompass a wider range of pushing the CPU beyond its
warrany.

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Link: http://lkml.kernel.org/r/20140226154949.GA770@redhat.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-03-20 16:28:09 -07:00
Vaibhav Nagarnaik 87291347c4 tracing: Fix array size mismatch in format string
In event format strings, the array size is reported in two locations.
One in array subscript and then via the "size:" attribute. The values
reported there have a mismatch.

For e.g., in sched:sched_switch the prev_comm and next_comm character
arrays have subscript values as [32] where as the actual field size is
16.

name: sched_switch
ID: 301
format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1;signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:char prev_comm[32];       offset:8;       size:16;        signed:1;
        field:pid_t prev_pid;   offset:24;      size:4; signed:1;
        field:int prev_prio;    offset:28;      size:4; signed:1;
        field:long prev_state;  offset:32;      size:8; signed:1;
        field:char next_comm[32];       offset:40;      size:16;        signed:1;
        field:pid_t next_pid;   offset:56;      size:4; signed:1;
        field:int next_prio;    offset:60;      size:4; signed:1;

After bisection, the following commit was blamed:
92edca0 tracing: Use direct field, type and system names

This commit removes the duplication of strings for field->name and
field->type assuming that all the strings passed in
__trace_define_field() are immutable. This is not true for arrays, where
the type string is created in event_storage variable and field->type for
all array fields points to event_storage.

Use __stringify() to create a string constant for the type string.

Also, get rid of event_storage and event_storage_mutex that are not
needed anymore.

also, an added benefit is that this reduces the overhead of events a bit more:

   text    data     bss     dec     hex filename
8424787 2036472 1302528 11763787         b3804b vmlinux
8420814 2036408 1302528 11759750         b37086 vmlinux.patched

Link: http://lkml.kernel.org/r/1392349908-29685-1-git-send-email-vnagarnaik@google.com

Cc: Laurent Chavey <chavey@google.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-20 13:21:05 -04:00
Tejun Heo e1b2dc176f cgroup: break kernfs active_ref protection in cgroup directory operations
cgroup_tree_mutex should nest above the kernfs active_ref protection;
however, cgroup_create() and cgroup_rename() were grabbing
cgroup_tree_mutex while under kernfs active_ref protection.  This has
actualy possibility to lead to deadlocks in case these operations race
against cgroup_rmdir() which invokes kernfs_remove() on directory
kernfs_node while holding cgroup_tree_mutex.

Neither cgroup_create() or cgroup_rename() requires active_ref
protection.  The former already has enough synchronization through
cgroup_lock_live_group() and the latter doesn't care, so this can be
fixed by updating both functions to break all active_ref protections
before grabbing cgroup_tree_mutex.

While this patch fixes the immediate issue, it probably needs further
work in the long term - kernfs directories should enable lockdep
annotations and maybe the better way to handle this is marking
directory nodes as not needing active_ref protection rather than
breaking it in each operation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-20 11:10:15 -04:00
Eric Paris 5e937a9ae9 syscall_get_arch: remove useless function arguments
Every caller of syscall_get_arch() uses current for the task and no
implementors of the function need args.  So just get rid of both of
those things.  Admittedly, since these are inline functions we aren't
wasting stack space, but it just makes the prototypes better.

Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@linux-mips.org
Cc: linux390@de.ibm.com
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-arch@vger.kernel.org
2014-03-20 10:11:59 -04:00
Joe Perches b7550787fe audit: remove stray newline from audit_log_execve_info() audit_panic() call
There's an unnecessary use of a \n in audit_panic.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:58 -04:00
Josh Boyer f12835276c audit: remove stray newlines from audit_log_lost messages
Calling audit_log_lost with a \n in the format string leads to extra
newlines in dmesg.  That function will eventually call audit_panic which
uses pr_err with an explicit \n included.  Just make these calls match the
others that lack \n.

Reported-by: Jonathan Kamens <jik@kamens.brookline.ma.us>
Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:58 -04:00
Eric Paris ddfad8affd audit: include subject in login records
The login uid change record does not include the selinux context of the
task logging in.  Add that information.

(Updated from 2011-01: RHBZ:670328 -- RGB)

Reported-by: Steve Grubb <sgrubb@redhat.com>
Acked-by: James Morris <jmorris@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Aristeu Rozanski <arozansk@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:57 -04:00
Richard Guy Briggs aa589a13b5 audit: remove superfluous new- prefix in AUDIT_LOGIN messages
The new- prefix on ses and auid are un-necessary and break ausearch.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:57 -04:00
Richard Guy Briggs 5a3cb3b6c3 audit: allow user processes to log from another PID namespace
Still only permit the audit logging daemon and control to operate from the
initial PID namespace, but allow processes to log from another PID namespace.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
(informed by ebiederman's c776b5d2)

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:56 -04:00
Richard Guy Briggs f1dc4867ff audit: anchor all pid references in the initial pid namespace
Store and log all PIDs with reference to the initial PID namespace and
use the access functions task_pid_nr() and task_tgid_nr() for task->pid
and task->tgid.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
(informed by ebiederman's c776b5d2)
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:55 -04:00
Richard Guy Briggs c92cdeb45e audit: convert PPIDs to the inital PID namespace.
sys_getppid() returns the parent pid of the current process in its own pid
namespace.  Since audit filters are based in the init pid namespace, a process
could avoid a filter or trigger an unintended one by being in an alternate pid
namespace or log meaningless information.

Switch to task_ppid_nr() for PPIDs to anchor all audit filters in the
init_pid_ns.

(informed by ebiederman's 6c621b7e)
Cc: stable@vger.kernel.org
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:55 -04:00
Richard Guy Briggs 4a3eb726d1 audit: rename the misleading audit_get_context() to audit_take_context()
"get" usually implies incrementing a refcount into a structure to indicate a
reference being held by another part of code.

Change this function name to indicate it is in fact being taken from it,
returning the value while clearing it in the supplying structure.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-20 10:11:54 -04:00
Eric W. Biederman 099dd23511 audit: Send replies in the proper network namespace.
In perverse cases of file descriptor passing the current network
namespace of a process and the network namespace of a socket used by
that socket may differ.  Therefore use the network namespace of the
appropiate socket to ensure replies always go to the appropiate
socket.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-20 10:11:02 -04:00
Eric W. Biederman 638a0fd2a0 audit: Use struct net not pid_t to remember the network namespce to reply in
While reading through 3.14-rc1 I found a pretty siginficant mishandling
of network namespaces in the recent audit changes.

In struct audit_netlink_list and audit_reply add a reference to the
network namespace of the caller and remove the userspace pid of the
caller.  This cleanly remembers the callers network namespace, and
removes a huge class of races and nasty failure modes that can occur
when attempting to relook up the callers network namespace from a pid_t
(including the caller's network namespace changing, pid wraparound, and
the pid simply not being present).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-20 10:10:53 -04:00
William Roberts 3f1c82502c audit: Audit proc/<pid>/cmdline aka proctitle
During an audit event, cache and print the value of the process's
proctitle value (proc/<pid>/cmdline). This is useful in situations
where processes are started via fork'd virtual machines where the
comm field is incorrect. Often times, setting the comm field still
is insufficient as the comm width is not very wide and most
virtual machine "package names" do not fit. Also, during execution,
many threads have their comm field set as well. By tying it back to
the global cmdline value for the process, audit records will be more
complete in systems with these properties. An example of where this
is useful and applicable is in the realm of Android. With Android,
their is no fork/exec for VM instances. The bare, preloaded Dalvik
VM listens for a fork and specialize request. When this request comes
in, the VM forks, and the loads the specific application (specializing).
This was done to take advantage of COW and to not require a load of
basic packages by the VM on very app spawn. When this spawn occurs,
the package name is set via setproctitle() and shows up in procfs.
Many of these package names are longer then 16 bytes, the historical
width of task->comm. Having the cmdline in the audit records will
couple the application back to the record directly. Also, on my
Debian development box, some audit records were more useful then
what was printed under comm.

The cached proctitle is tied to the life-cycle of the audit_context
structure and is built on demand.

Proctitle is controllable by userspace, and thus should not be trusted.
It is meant as an aid to assist in debugging. The proctitle event is
emitted during syscall audits, and can be filtered with auditctl.

Example:
type=AVC msg=audit(1391217013.924:386): avc:  denied  { getattr } for  pid=1971 comm="mkdir" name="/" dev="selinuxfs" ino=1 scontext=system_u:system_r:consolekit_t:s0-s0:c0.c255 tcontext=system_u:object_r:security_t:s0 tclass=filesystem
type=SYSCALL msg=audit(1391217013.924:386): arch=c000003e syscall=137 success=yes exit=0 a0=7f019dfc8bd7 a1=7fffa6aed2c0 a2=fffffffffff4bd25 a3=7fffa6aed050 items=0 ppid=1967 pid=1971 auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=4294967295 comm="mkdir" exe="/bin/mkdir" subj=system_u:system_r:consolekit_t:s0-s0:c0.c255 key=(null)
type=UNKNOWN[1327] msg=audit(1391217013.924:386):  proctitle=6D6B646972002D70002F7661722F72756E2F636F6E736F6C65

Acked-by: Steve Grubb <sgrubb@redhat.com> (wrt record formating)

Signed-off-by: William Roberts <wroberts@tresys.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
2014-03-20 10:10:52 -04:00
Srivatsa S. Bhat c270a81719 profile: Fix CPU hotplug callback registration
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the profile code by using this latter form of callback registration.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-20 13:43:48 +01:00
Srivatsa S. Bhat d39ad278a3 trace, ring-buffer: Fix CPU hotplug callback registration
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the tracing ring-buffer code by using this latter form of callback
registration.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-20 13:43:48 +01:00
Srivatsa S. Bhat 93ae4f978c CPU hotplug: Provide lockless versions of callback registration functions
The following method of CPU hotplug callback registration is not safe
due to the possibility of an ABBA deadlock involving the cpu_add_remove_lock
and the cpu_hotplug.lock.

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

The deadlock is shown below:

          CPU 0                                         CPU 1
          -----                                         -----

   Acquire cpu_hotplug.lock
   [via get_online_cpus()]

                                              CPU online/offline operation
                                              takes cpu_add_remove_lock
                                              [via cpu_maps_update_begin()]

   Try to acquire
   cpu_add_remove_lock
   [via register_cpu_notifier()]

                                              CPU online/offline operation
                                              tries to acquire cpu_hotplug.lock
                                              [via cpu_hotplug_begin()]

                            *** DEADLOCK! ***

The problem here is that callback registration takes the locks in one order
whereas the CPU hotplug operations take the same locks in the opposite order.
To avoid this issue and to provide a race-free method to register CPU hotplug
callbacks (along with initialization of already online CPUs), introduce new
variants of the callback registration APIs that simply register the callbacks
without holding the cpu_add_remove_lock during the registration. That way,
we can avoid the ABBA scenario. However, we will need to hold the
cpu_add_remove_lock throughout the entire critical section, to protect updates
to the callback/notifier chain.

This can be achieved by writing the callback registration code as follows:

	cpu_maps_update_begin(); [ or cpu_notifier_register_begin(); see below ]

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* This doesn't take the cpu_add_remove_lock */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_maps_update_done();  [ or cpu_notifier_register_done(); see below ]

Note that we can't use get_online_cpus() here instead of cpu_maps_update_begin()
because the cpu_hotplug.lock is dropped during the invocation of CPU_POST_DEAD
notifiers, and hence get_online_cpus() cannot provide the necessary
synchronization to protect the callback/notifier chains against concurrent
reads and writes. On the other hand, since the cpu_add_remove_lock protects
the entire hotplug operation (including CPU_POST_DEAD), we can use
cpu_maps_update_begin/done() to guarantee proper synchronization.

Also, since cpu_maps_update_begin/done() is like a super-set of
get/put_online_cpus(), the former naturally protects the critical sections
from concurrent hotplug operations.

Since the names cpu_maps_update_begin/done() don't make much sense in CPU
hotplug callback registration scenarios, we'll introduce new APIs named
cpu_notifier_register_begin/done() and map them to cpu_maps_update_begin/done().

In summary, introduce the lockless variants of un/register_cpu_notifier() and
also export the cpu_notifier_register_begin/done() APIs for use by modules.
This way, we provide a race-free way to register hotplug callbacks as well as
perform initialization for the CPUs that are already online.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-20 13:43:40 +01:00
Gautham R. Shenoy a19423b987 CPU hotplug: Add lockdep annotations to get/put_online_cpus()
Add lockdep annotations for get/put_online_cpus() and
cpu_hotplug_begin()/cpu_hotplug_end().

Cc: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-20 13:43:40 +01:00
Rafael J. Wysocki 36cc86e8ec Merge branches 'pm-runtime' and 'pm-sleep'
* pm-runtime:
  PM / Runtime: Update runtime_idle() documentation for return value meaning

* pm-sleep:
  PM / sleep: Correct whitespace errors in <linux/pm.h>
  PM: Add missing "freeze" state
  PM / Hibernate: Spelling s/anonymouns/anonymous/
  PM / Runtime: Add missing "it" in comment
  PM / suspend: Remove unnecessary !!
  PCI / PM: Resume runtime-suspended devices later during system suspend
  ACPI / PM: Resume runtime-suspended devices later during system suspend
  PM / sleep: Set pm_generic functions to NULL for !CONFIG_PM_SLEEP
  PM: fix typo in comment
  PM / hibernate: use name_to_dev_t to parse resume
  PM / wakeup: Include appropriate header file in kernel/power/wakelock.c
  PM / sleep: Move prototype declaration to header file kernel/power/power.h
  PM / sleep: Asynchronous threads for suspend_late
  PM / sleep: Asynchronous threads for suspend_noirq
  PM / sleep: Asynchronous threads for resume_early
  PM / sleep: Asynchronous threads for resume_noirq
  PM / sleep: Two flags for async suspend_noirq and suspend_late
2014-03-20 13:25:54 +01:00
Rafael J. Wysocki 165f5fd04a Merge branches 'pm-qos', 'pm-domains' and 'pm-drivers'
* pm-qos:
  PM / QoS: Add type to dev_pm_qos_add_ancestor_request() arguments
  ACPI / LPSS: Support for device latency tolerance PM QoS
  ACPI / scan: Add bind/unbind callbacks to struct acpi_scan_handler
  PM / QoS: Introcuce latency tolerance device PM QoS type
  PM / QoS: Add no_constraints_value field to struct pm_qos_constraints
  PM / QoS: Rename device resume latency QoS items

* pm-domains:
  PM / domains: Turn latency warning into debug message

* pm-drivers:
  PM: Add pm_runtime_suspend|resume_force functions
  PM / runtime: Fetch runtime PM callbacks using a macro
2014-03-20 13:25:36 +01:00
Viresh Kumar 6201b4d61f timer: Remove code redundancy while calling get_nohz_timer_target()
There are only two users of get_nohz_timer_target(): timer and hrtimer. Both
call it under same circumstances, i.e.

	#ifdef CONFIG_NO_HZ_COMMON
	       if (!pinned && get_sysctl_timer_migration() && idle_cpu(this_cpu))
	               return get_nohz_timer_target();
	#endif

So, it makes more sense to get all this as part of get_nohz_timer_target()
instead of duplicating code at two places. For this another parameter is
required to be passed to this routine, pinned.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1e1b53537217d58d48c2d7a222a9c3ac47d5b64c.1395140107.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-20 12:35:46 +01:00
Viresh Kumar c41eba7de1 timer: Use variable head instead of &work_list in __run_timers()
We already have a variable 'head' that points to '&work_list', and so
we should use that instead wherever possible.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Link: http://lkml.kernel.org/r/0d8645a6efc8360c4196c9797d59343abbfdcc5e.1395129136.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-20 12:35:45 +01:00
Linus Torvalds 7c3895383f Merge branch 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
 "One really late cgroup patch to fix error path in create_css().
  Hitting this bug would be pretty rare but still possible and it gets
  delayed we'd need to backport it through -stable anyway.  It only
  updates error path in create_css() and has low chance of new
  breakages"

* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix a failure path in create_css()
2014-03-19 16:13:40 -07:00
Tejun Heo 1b9aba49ea cgroup: fix cgroup_taskset walking order
cgroup_taskset is used to track and iterate target tasks while
migrating a task or process and should guarantee that the first task
iterated is the task group leader if a process is being migrated.

b3dc094e93 ("cgroup: use css_set->mg_tasks to track target tasks
during migration") replaced flex array cgroup_taskset->tc_array with
css_set->mg_tasks list to remove process size limit and dynamic
allocation during migration; unfortunately, it incorrectly used list
operations which don't preserve order breaking the guarantee that
cgroup_taskset_first() returns the leader for a process target.

Fix it by using order preserving list operations.  Note that as
multiple src_csets may map to a single dst_cset, the iteration order
may change across cgroup_task_migrate(); however, the leader is still
guaranteed to be the first entry.

The switch to list_splice_tail_init() at the end of cgroup_migrate()
isn't strictly necessary.  Let's still do it for consistency.

Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-19 17:43:21 -04:00
Bjorn Helgaas 6404e88e83 resources: Set type in __request_region()
We don't set the type (I/O, memory, etc.) of resources added by
__request_region(), which leads to confusing messages like this:

    address space collision: [io  0x1000-0x107f] conflicts with ACPI CPU throttle [??? 0x00001010-0x00001015 flags 0x80000000]

Set the type of a new resource added by __request_region() (used by
request_region() and request_mem_region()) to the type of its parent.  This
makes the resource tree internally consistent and fixes messages like the
above, where the ACPI CPU throttle resource really is an I/O port region,
but request_region() didn't fill in the type, so %pR didn't know how to
print it.

Sample dmesg showing the issue at the link below.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=71611
Reported-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-03-19 15:00:16 -06:00
Tejun Heo 8cbbf2c972 cgroup: implement CFTYPE_ONLY_ON_DFL
This cftype flag makes the file only appear on the default hierarchy.
This will later be used for cgroup.controllers file.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:55 -04:00
Tejun Heo a2dd424750 cgroup: make cgrp_dfl_root mountable
cgrp_dfl_root will be used as the default unified hierarchy.  This
patch makes cgrp_dfl_root mountable by making the following changes.

* cgroup_init_early() now initializes cgrp_dfl_root w/
  CGRP_ROOT_SANE_BEHAVIOR.  The default hierarchy is always sane.

* parse_cgroupfs_options() and cgroup_mount() are updated such that
  cgrp_dfl_root is mounted if sane_behavior is specified w/o any
  subsystems.

* rebind_subsystems() now populates the root directory of
  cgrp_dfl_root.  Note that the function still guarantees success of
  rebinding subsystems to cgrp_dfl_root.  If populating fails while
  rebinding to cgrp_dfl_root, it whines but ignores the error.

* For backward compatibility, the default hierarchy shows up in
  /proc/$PID/cgroup only after it's explicitly mounted so that
  userland which doesn't make use of it doesn't see any change.

* "current_css_set_cg_links" file of debug cgroup now treats the
  default hierarchy the same as other hierarchies.  This is visible to
  userland.  Given that it's for debug controller, this should be
  fine.

* While at it, implement cgroup_on_dfl() which tests whether a give
  cgroup is on the default hierarchy or not.

The above changes make cgrp_dfl_root mostly equivalent to other
controllers but the actual unified hierarchy behaviors are not
implemented yet.  Let's plug child cgroup creation in cgrp_dfl_root
from create_cgroup() for now.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:55 -04:00
Tejun Heo 4d3bb511b5 cgroup: drop const from @buffer of cftype->write_string()
cftype->write_string() just passes on the writeable buffer from kernfs
and there's no reason to add const restriction on the buffer.  The
only thing const achieves is unnecessarily complicating parsing of the
buffer.  Drop const from @buffer.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Michal Hocko <mhocko@suse.cz>                                           
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
2014-03-19 10:23:54 -04:00
Tejun Heo 3dd06ffa9d cgroup: rename cgroup_dummy_root and related names
The dummy root will be repurposed to serve as the default unified
hierarchy.  Let's rename things in preparation.

* s/cgroup_dummy_root/cgrp_dfl_root/
* s/cgroupfs_root/cgroup_root/ as we don't do fs part directly anymore
* s/cgroup_root->top_cgroup/cgroup_root->cgrp/ for brevity

This is pure rename.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:54 -04:00
Tejun Heo 944196278d cgroup: move ->subsys_mask from cgroupfs_root to cgroup
cgroupfs_root->subsys_mask represents the controllers attached to the
hierarchy.  This patch moves the field to cgroup.  Subsystem
initialization and rebinding updates the top cgroup's subsys_mask.
For !root cgroups, the subsys_mask bits are set from create_css() and
cleared from kill_css(), which effectively means that all cgroups will
have the same subsys_mask as the top cgroup.

While this doesn't make any difference now, this will help
implementation of the default unified hierarchy where !root cgroups
may have subsets of the top_cgroup's subsys_mask.

While at it, __kill_css() is split out of kill_css().  The former
doesn't care about the subsys_mask while the latter becomes noop if
the controller is already killed and clears the matching bit if not
before proceeding to killing the css.  This will be used later by the
default unified hierarchy implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:54 -04:00
Tejun Heo 5df3603229 cgroup: treat cgroup_dummy_root as an equivalent hierarchy during rebinding
Currently, while rebinding, cgroup_dummy_root serves as the anchor
point.  In addition to the target root, rebind_subsystems() takes
@added_mask and @removed_mask.  The subsystems specified in the former
are expected to be on the dummy root and then moved to the target
root.  The ones in the latter are moved from non-dummy root to dummy.
Now that the dummy root is a fully functional one and we're planning
to use it for the default unified hierarchy, this level of distinction
between dummy and non-dummy roots is quite awkward.

This patch updates rebind_subsystems() to take the target root and one
subsystem mask and move the specified subsystmes to the target root
which may or may not be the dummy root.  IOW, unbinding now becomes
moving the subsystems to the dummy root and binding to non-dummy root.
This makes the dummy root mostly equivalent to other hierarchies in
terms of the mechanism of moving subsystems around; however, we still
retain all the semantical restrictions so that this patch doesn't
introduce any visible behavior differences.  Another noteworthy detail
is that rebind_subsystems() guarantees that moving a subsystem to the
dummy root never fails so that valid unmounting attempts always
succeed.

This unifies binding and unbinding of subsystems.  The invocation
points of ->bind() were inconsistent between the two and now moved
after whole rebinding is complete.  This doesn't break the current
users and generally makes more sense.

All rebind_subsystems() users are converted accordingly.  Note that
cgroup_remount() now makes two calls to rebind_subsystems() to bind
and then unbind the requested subsystems.

This will allow repurposing of the dummy hierarchy as the default
unified hierarchy and shouldn't make any userland visible behavior
difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:54 -04:00
Tejun Heo 985ed67014 cgroup: use cgroup_setup_root() to initialize cgroup_dummy_root
cgroup_dummy_root is used to host controllers which aren't attached to
any other hierarchy.  The root is minimally set up during kernfs
bootstrap and didn't go through full hierarchy initialization.  We're
planning to use cgroup_dummy_root for the default unified hierarchy
and thus want it to be fully functional.

Replace the special initialization, which was collected into
cgroup_init() by the previous patch, with an invocation of
cgroup_setup_root().  This simplifies the init path and makes
cgroup_dummy_root a full hierarchy with its own kernfs_root and all.

As this puts the dummy hierarchy on the cgroup_roots list, rename
for_each_active_root() to for_each_root() and update its users to skip
the dummy root for now.

This patch doesn't cause any userland visible behavior changes at this
point.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:53 -04:00
Tejun Heo 172a2c0685 cgroup: reorganize cgroup bootstrapping
* Fields of init_css_set and css_set_count are now set using
  initializer instead of programmatically from cgroup_init_early().

* init_cgroup_root() now also takes @opts and performs the optional
  part of initialization too.  The leftover part of
  cgroup_root_from_opts() is collapsed into its only caller -
  cgroup_mount().

* Initialization of cgroup_root_count and linking of init_css_set are
  moved from cgroup_init_early() to to cgroup_init().  None of the
  early_init users depends on init_css_set being linked.

* Subsystem initializations are moved after dummy hierarchy init and
  init_css_set linking.

These changes reorganize the bootstrap logic so that the dummy
hierarchy can share the usual hierarchy init path and be made more
normal.  These changes don't make noticeable behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:53 -04:00
Tejun Heo 5d77381fd8 cgroup: relocate setting of CGRP_DEAD
In cgroup_destroy_locked(), move setting of CGRP_DEAD above
invocations of kill_css().  This doesn't make any visible behavior
difference now but will be used to inhibit manipulating controller
enable states of a dying cgroup on the unified hierarchy.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
2014-03-19 10:23:53 -04:00
Chema Gonzalez bab5c790cc genirq: procfs: Make smp_affinity values go+r
Includes:
- /proc/irq/default_smp_affinity
- /proc/irq/*/affinity_hint
- /proc/irq/*/smp_affinity
- /proc/irq/*/smp_affinity_list

Users can distill the same information by reading /proc/interrupts.

Signed-off-by: Chema Gonzalez <chema@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Link: http://lkml.kernel.org/r/1394765455-1217-1-git-send-email-chema@google.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-19 12:34:29 +01:00
Thomas Gleixner d532676cc7 softirq: Add linux/irq.h to make it compile again
On Sparc and S390 the removal of irq.h from kernel_stat.h causes:

   kernel/softirq.c:774:9: error: 'NR_IRQS_LEGACY' undeclared

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-19 11:28:14 +01:00
Li Zefan 3eb59ec64f cgroup: fix a failure path in create_css()
If online_css() fails, we should remove cgroup files belonging
to css->ss.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-18 17:15:36 -04:00
David A. Long 6fe50a28ba uprobes: allow ignoring of probe hits
Allow arches to decided to ignore a probe hit.  ARM will use this to
only call handlers if the conditions to execute a conditionally executed
instruction are satisfied.

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
2014-03-18 16:39:34 -04:00
David A. Long 09294e31b1 uprobes: Kconfig dependency fix
Suggested change from Oleg Nesterov. Fixes incomplete dependencies
for uprobes feature.

Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
2014-03-18 16:39:33 -04:00
Linus Torvalds 59bf6c3c6c Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Three small fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/clock: Prevent tracing recursion in sched_clock_cpu()
  stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus()
  sched/deadline: Deny unprivileged users to set/change SCHED_DEADLINE policy
2014-03-16 10:42:07 -07:00
Thomas Gleixner 328a4978df genirq: Add a new IRQCHIP_EOI_THREADED flag
The flag is necessary for interrupt chips which require an ACK/EOI
after the handler has run. In case of threaded handlers this needs to
happen after the threaded handler has completed before the unmask of
the interrupt.

The flag is only unseful in combination with the handle_fasteoi_irq
flow control handler.

It can be combined with the flag IRQCHIP_EOI_IF_HANDLED, so the EOI is
not issued when the interrupt is disabled or in progress.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-sunxi@googlegroups.com
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/1394733834-26839-2-git-send-email-hdegoede@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-14 13:43:33 +01:00
Jens Axboe 89f8b33ca1 block: remove old blk_iopoll_enabled variable
This was a debugging measure to toggle enabled/disabled
when testing. But for real production setups, it's not
safe to toggle this setting without either reloading
drivers of quiescing IO first. Neither of which the toggle
enforces.

Additionally, it makes drivers deal with the conditional
state.

Remove it completely. It's up to the driver whether iopoll
is enabled or not.

Signed-off-by: Jens Axboe <axboe@fb.com>
2014-03-13 09:38:42 -06:00
Frederic Weisbecker 300a9d887e sched: Remove needless round trip nsecs <-> tick conversion of steal time
When update_rq_clock_task() accounts the pending steal time for a task,
it converts the steal delta from nsecs to tick then from tick to nsecs.

There is no apparent good reason for doing that though because both
the task clock and the prev steal delta are u64 and store values
in nsecs.

So lets remove the needless conversion.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-03-13 15:56:44 +01:00
Frederic Weisbecker dee08a72de cputime: Fix jiffies based cputime assumption on steal accounting
The steal guest time accounting code assumes that cputime_t is based on
jiffies. So when CONFIG_NO_HZ_FULL=y, which implies that cputime_t
is based on nsecs, steal_account_process_tick() passes the delta in
jiffies to account_steal_time() which then accounts it as if it's a
value in nsecs.

As a result, accounting 1 second of steal time (with HZ=100 that would
be 100 jiffies) is spuriously accounted as 100 nsecs.

As such /proc/stat may report 0 values of steal time even when two
guests have run concurrently for a few seconds on the same host and
same CPU.

In order to fix this, lets convert the nsecs based steal delta to
cputime instead of jiffies by using the right conversion API.

Given that the steal time is stored in cputime_t and this type can have
a smaller granularity than nsecs, we only account the rounded converted
value and leave the remaining nsecs for the next deltas.

Reported-by: Huiqingding <huding@redhat.com>
Reported-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2014-03-13 15:56:44 +01:00
Mathieu Desnoyers 66cc69e34e Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE
Users have reported being unable to trace non-signed modules loaded
within a kernel supporting module signature.

This is caused by tracepoint.c:tracepoint_module_coming() refusing to
take into account tracepoints sitting within force-loaded modules
(TAINT_FORCED_MODULE). The reason for this check, in the first place, is
that a force-loaded module may have a struct module incompatible with
the layout expected by the kernel, and can thus cause a kernel crash
upon forced load of that module on a kernel with CONFIG_TRACEPOINTS=y.

Tracepoints, however, specifically accept TAINT_OOT_MODULE and
TAINT_CRAP, since those modules do not lead to the "very likely system
crash" issue cited above for force-loaded modules.

With kernels having CONFIG_MODULE_SIG=y (signed modules), a non-signed
module is tainted re-using the TAINT_FORCED_MODULE taint flag.
Unfortunately, this means that Tracepoints treat that module as a
force-loaded module, and thus silently refuse to consider any tracepoint
within this module.

Since an unsigned module does not fit within the "very likely system
crash" category of tainting, add a new TAINT_UNSIGNED_MODULE taint flag
to specifically address this taint behavior, and accept those modules
within Tracepoints. We use the letter 'X' as a taint flag character for
a module being loaded that doesn't know how to sign its name (proposed
by Steven Rostedt).

Also add the missing 'O' entry to trace event show_module_flags() list
for the sake of completeness.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
NAKed-by: Ingo Molnar <mingo@redhat.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: David Howells <dhowells@redhat.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-03-13 12:11:51 +10:30
Jiri Slaby 27bba4d6bb module: use pr_cont
When dumping loaded modules, we print them one by one in separate
printks. Let's use pr_cont as they are continuation prints.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-03-13 12:10:59 +10:30
Thomas Gleixner ffb12cf002 Merge branch 'irq/for-gpio' into irq/core
Merge the request/release callbacks which are in a separate branch for
consumption by the gpio folks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-12 16:01:07 +01:00
Thomas Gleixner c1bacbae81 genirq: Provide irq_request/release_resources chip callbacks
For certain irq types, e.g. gpios, it's necessary to request resources
before starting up the irq.

This might fail so we cannot use the irq_startup() callback because we
might call the irq_set_type() callback before that which does not make
sense when the resource is not available. Calling irq_startup() before
irq_set_type() can lead to spurious interrupts which is not desired
either.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org 
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1403080857160.18573@ionos.tec.linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-12 16:00:24 +01:00
Peter Zijlstra 6f008e72cd locking/mutex: Fix debug checks
OK, so commit:

  1d8fe7dc80 ("locking/mutexes: Unlock the mutex without the wait_lock")

generates this boot warning when CONFIG_DEBUG_MUTEXES=y:

  WARNING: CPU: 0 PID: 139 at /usr/src/linux-2.6/kernel/locking/mutex-debug.c:82 debug_mutex_unlock+0x155/0x180() DEBUG_LOCKS_WARN_ON(lock->owner != current)

And that makes sense, because as soon as we release the lock a
new owner can come in...

One would think that !__mutex_slowpath_needs_to_unlock()
implementations suffer the same, but for DEBUG we fall back to
mutex-null.h which has an unconditional 1 for that.

The mutex debug code requires the mutex to be unlocked after
doing the debug checks, otherwise it can find inconsistent
state.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: jason.low2@hp.com
Link: http://lkml.kernel.org/r/20140312122442.GB27965@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 13:49:47 +01:00
Alex Shi 6037dd1a49 sched: Clean up the task_hot() function
task_hot() doesn't need the 'sched_domain' parameter, so remove it.

Signed-off-by: Alex Shi <alex.shi@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394607111-1904-1-git-send-email-alex.shi@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 10:49:01 +01:00
Vincent Guittot a2cd42601b sched: Remove double calculation in fix_small_imbalance()
The tmp value has been already calculated in:

  scaled_busy_load_per_task =
		(busiest->load_per_task * SCHED_POWER_SCALE) /
		busiest->group_power;

Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394555166-22894-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 10:49:00 +01:00
Steven Rostedt 383afd0971 sched: Fix broken setscheduler()
I decided to run my tests on linux-next, and my wakeup_rt tracer was
broken. After running a bisect, I found that the problem commit was:

   linux-next commit c365c292d0
   "sched: Consider pi boosting in setscheduler()"

And the reason the wake_rt tracer test was failing, was because it had
no RT task to trace. I first noticed this when running with
sched_switch event and saw that my RT task still had normal SCHED_OTHER
priority. Looking at the problem commit, I found:

 -       p->normal_prio = normal_prio(p);
 -       p->prio = rt_mutex_getprio(p);

With no

 +       p->normal_prio = normal_prio(p);
 +       p->prio = rt_mutex_getprio(p);

Reading what the commit is suppose to do, I realize that the p->prio
can't be set if the task is boosted with a higher prio, but the
p->normal_prio still needs to be set regardless, otherwise, when the
task is deboosted, it wont get the new priority.

The p->prio has to be set before "check_class_changed()" is called,
otherwise the class wont be changed.

Also added fix to newprio to include a check for deadline policy that
was missing. This change was suggested by Juri Lelli.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: SebastianAndrzej Siewior <bigeasy@linutronix.de>
Cc: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140306120438.638bfe94@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-12 10:48:59 +01:00
Sasha Levin d88471cb8b ftrace: Constify ftrace_text_reserved
Link: http://lkml.kernel.org/r/1357772960-4436-5-git-send-email-sasha.levin@oracle.com

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-11 22:52:43 -04:00
Mathieu Desnoyers 3bbc8db341 tracepoints: API doc update to tracepoint_probe_register() return value
Describe the return values of tracepoint_probe_register(), including
-ENODEV added by commit:

Author: Steven Rostedt <rostedt@goodmis.org>

    tracing: Warn if a tracepoint is not set via debugfs

Link: http://lkml.kernel.org/r/1394499898-1537-2-git-send-email-mathieu.desnoyers@efficios.com

CC: Ingo Molnar <mingo@kernel.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-11 21:53:50 -04:00
Mathieu Desnoyers 4c11628a16 tracepoints: API doc update to data argument
Describe the @data argument (probe private data).

Link: http://lkml.kernel.org/r/1394587948-27878-1-git-send-email-mathieu.desnoyers@efficios.com

Fixes: 38516ab59f "tracing: Let tracepoints have data passed to tracepoint callbacks"
CC: Ingo Molnar <mingo@kernel.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-11 21:51:40 -04:00
Geert Uytterhoeven af02b5fdb1 PM: Add missing "freeze" state
Fix descriptions of /sys/power/state in the documentation and in
a code comment.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-12 00:54:53 +01:00
Geert Uytterhoeven 4d4348202b PM / Hibernate: Spelling s/anonymouns/anonymous/
Spelling fix.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-12 00:54:53 +01:00
Jiri Slaby db0fbadcbd ftrace: Fix compilation warning about control_ops_free
With CONFIG_DYNAMIC_FTRACE=n, I see a warning:
kernel/trace/ftrace.c:240:13: warning: 'control_ops_free' defined but not used
 static void control_ops_free(struct ftrace_ops *ops)
             ^
Move that function around to an already existing #ifdef
CONFIG_DYNAMIC_FTRACE block as the function is used solely from the
dynamic function tracing functions.

Link: http://lkml.kernel.org/r/1394484131-5107-1-git-send-email-jslaby@suse.cz

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-11 19:38:20 -04:00
Linus Torvalds adf961d7e8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull audit namespace fixes from Eric Biederman:
 "Starting with 3.14-rc1 the audit code is faulty (think oopses and
  races) with respect to how it computes the network namespace of which
  socket to reply to, and I happened to notice by chance when reading
  through the code.

  My testing and the automated build bots don't find any problems with
  these fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  audit: Update kdoc for audit_send_reply and audit_list_rules_send
  audit: Send replies in the proper network namespace.
  audit: Use struct net not pid_t to remember the network namespce to reply in
2014-03-11 10:17:50 -07:00
Peter Zijlstra 34c6bc2c91 locking/mutexes: Add extra reschedule point
Add in an extra reschedule in an attempt to avoid getting reschedule
the moment we've acquired the lock.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-zah5eyn9gu7qlgwh9r6n2anc@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:14:59 +01:00
Peter Zijlstra fb0527bd5e locking/mutexes: Introduce cancelable MCS lock for adaptive spinning
Since we want a task waiting for a mutex_lock() to go to sleep and
reschedule on need_resched() we must be able to abort the
mcs_spin_lock() around the adaptive spin.

Therefore implement a cancelable mcs lock.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: chegu_vinod@hp.com
Cc: paulmck@linux.vnet.ibm.com
Cc: Waiman.Long@hp.com
Cc: torvalds@linux-foundation.org
Cc: tglx@linutronix.de
Cc: riel@redhat.com
Cc: akpm@linux-foundation.org
Cc: davidlohr@hp.com
Cc: hpa@zytor.com
Cc: andi@firstfloor.org
Cc: aswin@hp.com
Cc: scott.norton@hp.com
Cc: Jason Low <jason.low2@hp.com>
Link: http://lkml.kernel.org/n/tip-62hcl5wxydmjzd182zhvk89m@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:14:56 +01:00
Jason Low 1d8fe7dc80 locking/mutexes: Unlock the mutex without the wait_lock
When running workloads that have high contention in mutexes on an 8 socket
machine, mutex spinners would often spin for a long time with no lock owner.

The main reason why this is occuring is in __mutex_unlock_common_slowpath(),
if __mutex_slowpath_needs_to_unlock(), then the owner needs to acquire the
mutex->wait_lock before releasing the mutex (setting lock->count to 1). When
the wait_lock is contended, this delays the mutex from being released.
We should be able to release the mutex without holding the wait_lock.

Signed-off-by: Jason Low <jason.low2@hp.com>
Cc: chegu_vinod@hp.com
Cc: paulmck@linux.vnet.ibm.com
Cc: Waiman.Long@hp.com
Cc: torvalds@linux-foundation.org
Cc: tglx@linutronix.de
Cc: riel@redhat.com
Cc: akpm@linux-foundation.org
Cc: davidlohr@hp.com
Cc: hpa@zytor.com
Cc: andi@firstfloor.org
Cc: aswin@hp.com
Cc: scott.norton@hp.com
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1390936396-3962-4-git-send-email-jason.low2@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:14:54 +01:00
Jason Low 47667fa150 locking/mutexes: Modify the way optimistic spinners are queued
The mutex->spin_mlock was introduced in order to ensure that only 1 thread
spins for lock acquisition at a time to reduce cache line contention. When
lock->owner is NULL and the lock->count is still not 1, the spinner(s) will
continually release and obtain the lock->spin_mlock. This can generate
quite a bit of overhead/contention, and also might just delay the spinner
from getting the lock.

This patch modifies the way optimistic spinners are queued by queuing before
entering the optimistic spinning loop as oppose to acquiring before every
call to mutex_spin_on_owner(). So in situations where the spinner requires
a few extra spins before obtaining the lock, then there will only be 1 spinner
trying to get the lock and it will avoid the overhead from unnecessarily
unlocking and locking the spin_mlock.

Signed-off-by: Jason Low <jason.low2@hp.com>
Cc: tglx@linutronix.de
Cc: riel@redhat.com
Cc: akpm@linux-foundation.org
Cc: davidlohr@hp.com
Cc: hpa@zytor.com
Cc: andi@firstfloor.org
Cc: aswin@hp.com
Cc: scott.norton@hp.com
Cc: chegu_vinod@hp.com
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Cc: torvalds@linux-foundation.org
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1390936396-3962-3-git-send-email-jason.low2@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:14:53 +01:00
Jason Low 46af29e479 locking/mutexes: Return false if task need_resched() in mutex_can_spin_on_owner()
The mutex_can_spin_on_owner() function should also return false if the
task needs to be rescheduled to avoid entering the MCS queue when it
needs to reschedule.

Signed-off-by: Jason Low <jason.low2@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman.Long@hp.com
Cc: torvalds@linux-foundation.org
Cc: tglx@linutronix.de
Cc: riel@redhat.com
Cc: akpm@linux-foundation.org
Cc: davidlohr@hp.com
Cc: hpa@zytor.com
Cc: andi@firstfloor.org
Cc: aswin@hp.com
Cc: scott.norton@hp.com
Cc: chegu_vinod@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1390936396-3962-2-git-send-email-jason.low2@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:14:52 +01:00
Peter Zijlstra c9122da1e2 locking: Move mcs_spinlock.h into kernel/locking/
The mcs_spinlock code is not meant (or suitable) as a generic locking
primitive, therefore take it away from the normal includes and place
it in kernel/locking/.

This way the locking primitives implemented there can use it as part
of their implementation but we do not risk it getting used
inapropriately.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-byirmpamgr7h25m5kyavwpzx@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:14:52 +01:00
Mike Galbraith 156654f491 sched/numa: Move task_numa_free() to __put_task_struct()
Bad idea on -rt:

[  908.026136]  [<ffffffff8150ad6a>] rt_spin_lock_slowlock+0xaa/0x2c0
[  908.026145]  [<ffffffff8108f701>] task_numa_free+0x31/0x130
[  908.026151]  [<ffffffff8108121e>] finish_task_switch+0xce/0x100
[  908.026156]  [<ffffffff81509c0a>] thread_return+0x48/0x4ae
[  908.026160]  [<ffffffff8150a095>] schedule+0x25/0xa0
[  908.026163]  [<ffffffff8150ad95>] rt_spin_lock_slowlock+0xd5/0x2c0
[  908.026170]  [<ffffffff810658cf>] get_signal_to_deliver+0xaf/0x680
[  908.026175]  [<ffffffff8100242d>] do_signal+0x3d/0x5b0
[  908.026179]  [<ffffffff81002a30>] do_notify_resume+0x90/0xe0
[  908.026186]  [<ffffffff81513176>] int_signal+0x12/0x17
[  908.026193]  [<00007ff2a388b1d0>] 0x7ff2a388b1cf

and since upstream does not mind where we do this, be a bit nicer ...

Signed-off-by: Mike Galbraith <bitbucket@online.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1393568591.6018.27.camel@marge.simpson.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:43 +01:00
Kirill Tkhai 35805ff8f4 sched/fair: Fix endless loop in idle_balance()
Check for fair tasks number to decide, that we've pulled a task.
rq's nr_running may contain throttled RT tasks.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394118975.19290.104.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:41 +01:00
Kirill Tkhai 4c6c4e38c4 sched/core: Fix endless loop in pick_next_task()
1) Single cpu machine case.

When rq has only RT tasks, but no one of them can be picked
because of throttling, we enter in endless loop.

pick_next_task_{dl,rt} return NULL.

In pick_next_task_fair() we permanently go to retry

	if (rq->nr_running != rq->cfs.h_nr_running)
		return RETRY_TASK;

(rq->nr_running is not being decremented when rt_rq becomes
throttled).

No chances to unthrottle any rt_rq or to wake fair here,
because of rq is locked permanently and interrupts are
disabled.

2) In case of SMP this can cause a hang too. Although we unlock
   rq in idle_balance(), interrupts are still disabled.

The solution is to check for available tasks in DL and RT
classes instead of checking for sum.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1394098321.19290.11.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:39 +01:00
Kirill Tkhai e4aa358b6c sched/fair: Push down check for high priority class task into idle_balance()
We close idle_exit_fair() bracket in case of we've pulled something or we've received
task of high priority class.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/1394098315.19290.10.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:37 +01:00
Kirill Tkhai 734ff2a71f sched/rt: Fix picking RT and DL tasks from empty queue
The problems:

1) We check for rt_nr_running before call of put_prev_task().
   If previous task is RT, its rt_rq may become throttled
   and dequeued after this call.

In case of p is from rt->rq this just causes picking a task
from throttled queue, but in case of its rt_rq is child
we are guaranteed catch BUG_ON.

2) The same with deadline class. The only difference we operate
   on only dl_rq.

This patch fixes all the above problems and it adds a small skip in the
DL update like we've already done for RT class:

	if (unlikely((s64)delta_exec <= 0))
		return;

This will optimize sequential update_curr_dl() calls a little.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Link: http://lkml.kernel.org/r/1393946746.3643.3.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 12:05:35 +01:00
Jiri Olsa 63c45f4ba5 perf: Disallow user-space stack dumps for function trace events
Recent issues with user space callchains processing within
page fault handler tracing showed as Peter said 'there's
just too much fail surface'.

The user space stack dump is just another source of the this issue.

Related list discussions:
  http://marc.info/?t=139302086500001&r=1&w=2
  http://marc.info/?t=139301437300003&r=1&w=2

Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1393775800-13524-3-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:57:58 +01:00
Jiri Olsa cfa77bc4af perf: Disallow user-space callchains for function trace events
Recent issues with user space callchains processing within
page fault handler tracing showed as Peter said 'there's
just too much fail surface'.

Related list discussions:

  http://marc.info/?t=139302086500001&r=1&w=2
  http://marc.info/?t=139301437300003&r=1&w=2

Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1393775800-13524-2-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:57:57 +01:00
Ingo Molnar 0066f3b93e Merge branch 'perf/urgent' into perf/core
Merge the latest fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:53:50 +01:00
Daniel Lezcano a1d028bd6d sched/idle: Add more comments to the code
The idle main function is a complex and a critical function. Added more
comments to the code.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: rjw@rjwysocki.net
Cc: preeti@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1393832934-11625-5-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:52:49 +01:00
Daniel Lezcano 8ca3c6424f sched/idle: Move idle conditions in cpuidle_idle main function
This patch moves the condition before entering idle into the cpuidle main
function located in idle.c. That simplify the idle mainloop functions and
increase the readibility of the conditions to enter truly idle.

This patch is code reorganization and does not change the behavior of the
function.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: rjw@rjwysocki.net
Cc: nicolas.pitre@linaro.org
Cc: preeti@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1393832934-11625-4-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:52:48 +01:00
Daniel Lezcano c8cc7d4de7 sched/idle: Reorganize the idle loop
Now that we have the main cpuidle function in idle.c, move some code from
the idle mainloop to this function for the sake of clarity.

That removes if then else indentation difficult to follow when looking at the
code. This patch does not change the current behavior.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: rjw@rjwysocki.net
Cc: preeti@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1393832934-11625-3-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:52:47 +01:00
Daniel Lezcano 30cdd69e2a cpuidle/idle: Move the cpuidle_idle_call function to idle.c
The cpuidle_idle_call does nothing more than calling the three individuals
function and is no longer used by any arch specific code but only in the
cpuidle framework code.

We can move this function into the idle task code to ensure better
proximity to the scheduler code.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: rjw@rjwysocki.net
Cc: preeti@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1393832934-11625-2-git-send-email-daniel.lezcano@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:52:45 +01:00
Ingo Molnar a02ed5e3e0 Merge branch 'sched/urgent' into sched/core
Pick up fixes before queueing up new changes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:34:27 +01:00
Fernando Luis Vazquez Cao 96b3d28bf4 sched/clock: Prevent tracing recursion in sched_clock_cpu()
Prevent tracing of preempt_disable/enable() in sched_clock_cpu().
When CONFIG_DEBUG_PREEMPT is enabled, preempt_disable/enable() are
traced and this causes trace_clock() users (and probably others) to
go into an infinite recursion. Systems with a stable sched_clock()
are not affected.

This problem is similar to that fixed by upstream commit 95ef1e5292
("KVM guest: prevent tracing recursion with kvmclock").

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1394083528.4524.3.camel@nexus
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:33:48 +01:00
Peter Zijlstra 177c53d943 stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus()
We must use smp_call_function_single(.wait=1) for the
irq_cpu_stop_queue_work() to ensure the queueing is actually done under
stop_cpus_lock. Without this we could have dropped the lock by the time
we do the queueing and get the race we tried to fix.

Fixes: 7053ea1a34 ("stop_machine: Fix race between stop_two_cpus() and stop_cpus()")

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140228123905.GK3104@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:33:47 +01:00
Juri Lelli d44753b843 sched/deadline: Deny unprivileged users to set/change SCHED_DEADLINE policy
Deny the use of SCHED_DEADLINE policy to unprivileged users.
Even if root users can set the policy for normal users, we
don't want the latter to be able to change their parameters
(safest behavior).

Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1393844961-18097-1-git-send-email-juri.lelli@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-11 11:33:46 +01:00
Viresh Kumar 7500d9363f PM / suspend: Remove unnecessary !!
Double ! or !! are normally required to get 0 or 1 out of a expression. A
comparision always returns 0 or 1 and hence there is no need to apply double !
over it again.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-11 01:45:21 +01:00
Johannes Weiner e97ca8e5b8 mm: fix GFP_THISNODE callers and clarify
GFP_THISNODE is for callers that implement their own clever fallback to
remote nodes.  It restricts the allocation to the specified node and
does not invoke reclaim, assuming that the caller will take care of it
when the fallback fails, e.g.  through a subsequent allocation request
without GFP_THISNODE set.

However, many current GFP_THISNODE users only want the node exclusive
aspect of the flag, without actually implementing their own fallback or
triggering reclaim if necessary.  This results in things like page
migration failing prematurely even when there is easily reclaimable
memory available, unless kswapd happens to be running already or a
concurrent allocation attempt triggers the necessary reclaim.

Convert all callsites that don't implement their own fallback strategy
to __GFP_THISNODE.  This restricts the allocation a single node too, but
at the same time allows the allocator to enter the slowpath, wake
kswapd, and invoke direct reclaim if necessary, to make the allocation
happen when memory is full.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Jan Stancek <jstancek@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-10 17:26:19 -07:00
Thomas Gleixner f9a8a0abc3 Merge branch 'fortglx/3.15/time' of git://git.linaro.org/people/john.stultz/linux into timers/core
- support CLOCK_BOOTTIME clock in timerfd
 - Add missing header file

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-10 19:53:09 +01:00
Eric W. Biederman d211f177b2 audit: Update kdoc for audit_send_reply and audit_list_rules_send
The kbuild test robot reported:
> tree:   git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git for-next
> head:   6f285b19d0
> commit: 6f285b19d0 [2/2] audit: Send replies in the proper network namespace.
> reproduce: make htmldocs
>
> >> Warning(kernel/audit.c:575): No description found for parameter 'request_skb'
> >> Warning(kernel/audit.c:575): Excess function parameter 'portid' description in 'audit_send_reply'
> >> Warning(kernel/auditfilter.c:1074): No description found for parameter 'request_skb'
> >> Warning(kernel/auditfilter.c:1074): Excess function parameter 'portid' description in 'audit_list_rules_s

Which was caused by my failure to update the kdoc annotations when I
updated the functions.  Fix that small oversight now.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-03-08 15:31:54 -08:00
Linus Torvalds ca62eec4e5 Merge branch 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "Two cpuset locking fixes from Li.  Both tagged for -stable"

* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: fix a race condition in __cpuset_node_allowed_softwall()
  cpuset: fix a locking issue in cpuset_migrate_mm()
2014-03-08 11:57:38 -08:00
Linus Torvalds 721f0c1260 In the past, I've had lots of reports about trace events not working.
Developers would say they put a trace_printk() before and after the trace
 event but when they enable it (and the trace event said it was enabled) they
 would see the trace_printks but not the trace event.
 
 I was not able to reproduce this, but that's because I wasn't looking at
 the right location. Recently, another bug came up that showed the issue.
 
 If your kernel supports signed modules but allows for non-signed modules
 to be loaded, then when one is, the kernel will silently set the
 MODULE_FORCED taint on the module. Although, this taint happens without
 the need for insmod --force or anything of the kind, it labels the
 module with that taint anyway.
 
 If this tainted module has tracepoints, the tracepoints will be ignored
 because of the MODULE_FORCED taint. But no error message will be
 displayed. Worse yet, the event infrastructure will still be created
 letting users enable the trace event represented by the tracepoint,
 although that event will never actually be enabled. This is because
 the tracepoint infrastructure allows for non-existing tracepoints to
 be enabled for new modules to arrive and have their tracepoints set.
 
 Although there are several things wrong with the above, this change
 only addresses the creation of the trace event files for tracepoints
 that are not created when a module is loaded and is tainted. This change
 will print an error message about the module being tainted and not the
 trace events will not be created, and it does not create the trace event
 infrastructure.
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Merge tag 'trace-fixes-v3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "In the past, I've had lots of reports about trace events not working.
  Developers would say they put a trace_printk() before and after the
  trace event but when they enable it (and the trace event said it was
  enabled) they would see the trace_printks but not the trace event.

  I was not able to reproduce this, but that's because I wasn't looking
  at the right location.  Recently, another bug came up that showed the
  issue.

  If your kernel supports signed modules but allows for non-signed
  modules to be loaded, then when one is, the kernel will silently set
  the MODULE_FORCED taint on the module.  Although, this taint happens
  without the need for insmod --force or anything of the kind, it labels
  the module with that taint anyway.

  If this tainted module has tracepoints, the tracepoints will be
  ignored because of the MODULE_FORCED taint.  But no error message will
  be displayed.  Worse yet, the event infrastructure will still be
  created letting users enable the trace event represented by the
  tracepoint, although that event will never actually be enabled.  This
  is because the tracepoint infrastructure allows for non-existing
  tracepoints to be enabled for new modules to arrive and have their
  tracepoints set.

  Although there are several things wrong with the above, this change
  only addresses the creation of the trace event files for tracepoints
  that are not created when a module is loaded and is tainted.  This
  change will print an error message about the module being tainted and
  not the trace events will not be created, and it does not create the
  trace event infrastructure"

* tag 'trace-fixes-v3.14-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Do not add event files for modules that fail tracepoints
2014-03-07 16:32:40 -08:00
Linus Torvalds 27ea0f7811 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 - a bugfix for a long standing waitqueue race
 - a trivial fix for a missing include

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Include missing header file in irqdomain.c
  genirq: Remove racy waitqueue_active check
2014-03-07 16:31:41 -08:00
Richard Guy Briggs f952d10ff4 audit: Use more current logging style again
Add pr_fmt to prefix "audit: " to output
Convert printk(KERN_<LEVEL> to pr_<level>
Coalesce formats

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-07 11:48:15 -05:00
Eric Paris b7d3622a39 Linux 3.13
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Merge tag 'v3.13' into for-3.15

Linux 3.13

Conflicts:
	include/net/xfrm.h

Simple merge where v3.13 removed 'extern' from definitions and the audit
tree did s/u32/unsigned int/ to the same definitions.
2014-03-07 11:41:32 -05:00
Petr Mladek cd21067f69 ftrace: Warn on error when modifying ftrace function
We should print some warning and kill ftrace functionality when the ftrace
function is not set correctly. Otherwise, ftrace might do crazy things without
an explanation. The error value has been ignored so far.

Note that an error that happens during updating all the traced calls is handled
in ftrace_replace_code(). We print more details about the particular
failing address via ftrace_bug() there.

Link: http://lkml.kernel.org/r/1393258342-29978-3-git-send-email-pmladek@suse.cz

Signed-off-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:15 -05:00
Jiri Slaby 3a36cb11ca ftrace: Do not pass data to ftrace_dyn_arch_init
As the data parameter is not really used by any ftrace_dyn_arch_init,
remove that from ftrace_dyn_arch_init. This also removes the addr
local variable from ftrace_init which is now unused.

Note the documentation was imprecise as it did not suggest to set
(*data) to 0.

Link: http://lkml.kernel.org/r/1393268401-24379-4-git-send-email-jslaby@suse.cz

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:14 -05:00
Jiri Slaby af64a7cb09 ftrace: Pass retval through return in ftrace_dyn_arch_init()
No architecture uses the "data" parameter in ftrace_dyn_arch_init() in any
way, it just sets the value to 0. And this is used as a return value
in the caller -- ftrace_init, which just checks the retval against
zero.

Note there is also "return 0" in every ftrace_dyn_arch_init.  So it is
enough to check the retval and remove all the indirect sets of data on
all archs.

Link: http://lkml.kernel.org/r/1393268401-24379-3-git-send-email-jslaby@suse.cz

Cc: linux-arch@vger.kernel.org
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:13 -05:00
Jiri Slaby c867ccd838 ftrace: Inline the code from ftrace_dyn_table_alloc()
The function used to do allocations some time ago. This no longer
happens and it only checks the count and prints some info. This patch
inlines the body to the only caller. There are two reasons:
* the name of the function was misleading
* it's clear what is going on in ftrace_init now

Link: http://lkml.kernel.org/r/1393268401-24379-2-git-send-email-jslaby@suse.cz

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:12 -05:00
Jiri Slaby 1dc43cf0be ftrace: Cleanup of global variables ftrace_new_pgs and ftrace_update_cnt
Some of them can be local to functions, so make them local and pass
them as parameters where needed:
* __start_mcount_loc+__stop_mcount_loc are local to ftrace_init
* ftrace_new_pgs -> new_pgs/start_pg
* ftrace_update_cnt -> local update_cnt in ftrace_update_code

Link: http://lkml.kernel.org/r/1393268401-24379-1-git-send-email-jslaby@suse.cz

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:12 -05:00
Steven Rostedt b196e2b9e2 tracing: Warn if a tracepoint is not set via debugfs
Tracepoints were made to allow enabling a tracepoint in a module before that
module was loaded. When a tracepoint is enabled and it does not exist, the
name is stored and will be enabled when the tracepoint is created.

The problem with this approach is that when a tracepoint is enabled when
it expects to be there, it gives no warning that it does not exist.

To add salt to the wound, if a module is added and sets the FORCED flag, which
can happen if it isn't signed properly, the tracepoint code will not enabled
the tracepoints, but they will be created in the debugfs system! When a user
goes to enable the tracepoint, the tracepoint code will not see it existing
and will think it is to be enabled later AND WILL NOT GIVE A WARNING.

The tracing will look like it succeeded but will actually be doing nothing.
This will cause lots of confusion and headaches for developers trying to
figure out why they are not seeing their tracepoints.

Link: http://lkml.kernel.org/r/20140213154507.4040fb06@gandalf.local.home

Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reported-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:07 -05:00
Steven Rostedt 3fd40d1ee6 tracing: Use helper functions in event assignment to shrink macro size
The functions that assign the contents for the ftrace events are
defined by the TRACE_EVENT() macros. Each event has its own unique
way to assign data to its buffer. When you have over 500 events,
that means there's 500 functions assigning data uniquely for each
event (not really that many, as DECLARE_EVENT_CLASS() and multiple
DEFINE_EVENT()s will only need a single function).

By making helper functions in the core kernel to do some of the work
instead, we can shrink the size of the kernel down a bit.

With a kernel configured with 502 events, the change in size was:

   text    data     bss     dec     hex filename
12987390        1913504 9785344 24686238        178ae9e /tmp/vmlinux
12959102        1913504 9785344 24657950        178401e /tmp/vmlinux.patched

That's a total of 28288 bytes, which comes down to 56 bytes per event.

Link: http://lkml.kernel.org/r/20120810034708.370808175@goodmis.org

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:07 -05:00
Steven Rostedt 35bb4399bd tracing: Move event storage for array from macro to standalone function
The code that shows array fields for events is defined for all events.
This can add up quite a bit when you have over 500 events.

By making helper functions in the core kernel to do the work
instead, we can shrink the size of the kernel down a bit.

With a kernel configured with 502 events, the change in size was:

   text    data     bss     dec     hex filename
12990946        1913568 9785344 24689858        178bcc2 /tmp/vmlinux
12987390        1913504 9785344 24686238        178ae9e /tmp/vmlinux.patched

That's a total of 3556 bytes, which comes down to 7 bytes per event.
Although it's not much, this code is just called at initialization of
the events.

Link: http://lkml.kernel.org/r/20120810034708.084036335@goodmis.org

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:06 -05:00
Steven Rostedt 1d6bae966e tracing: Move raw output code from macro to standalone function
The code for trace events to format the raw recorded event data
into human readable format in the 'trace' file is repeated for every
event in the system. When you have over 500 events, this can add up
quite a bit.

By making helper functions in the core kernel to do the work
instead, we can shrink the size of the kernel down a bit.

With a kernel configured with 502 events, the change in size was:

   text    data     bss     dec     hex filename
12991007        1913568 9785344 24689919        178bcff /tmp/vmlinux.orig
12990946        1913568 9785344 24689858        178bcc2 /tmp/vmlinux.patched

Note, this version does not save as much as the version of this patch
I had a few years ago. That is because in the mean time, commit
f71130de5c ("tracing: Add a helper function for event print functions")
did a lot of the work my original patch did. But this change helps
slightly, and is part of a larger clean up to reduce the size much further.

Link: http://lkml.kernel.org/r/20120810034707.378538034@goodmis.org

Cc: Li Zefan <lizefan@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07 10:06:05 -05:00
Heiko Carstens 2f2728f6de mm/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types
In order to allow the COMPAT_SYSCALL_DEFINE macro generate code that
performs proper zero and sign extension convert all 64 bit parameters
to their corresponding 32 bit compat counterparts.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-06 16:30:47 +01:00
Heiko Carstens ca2c405ab9 kexec/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types
In order to allow the COMPAT_SYSCALL_DEFINE macro generate code that
performs proper zero and sign extension convert all 64 bit parameters
to their corresponding 32 bit compat counterparts.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-06 16:30:46 +01:00
Heiko Carstens 62a6fa9768 kernel/compat: convert to COMPAT_SYSCALL_DEFINE
Convert all compat system call functions where all parameter types
have a size of four or less than four bytes, or are pointer types
to COMPAT_SYSCALL_DEFINE.
The implicit casts within COMPAT_SYSCALL_DEFINE will perform proper
zero and sign extension to 64 bit of all parameters if needed.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-06 15:35:10 +01:00
Roman Pen af5040da01 blktrace: fix accounting of partially completed requests
trace_block_rq_complete does not take into account that request can
be partially completed, so we can get the following incorrect output
of blkparser:

  C   R 232 + 240 [0]
  C   R 240 + 232 [0]
  C   R 248 + 224 [0]
  C   R 256 + 216 [0]

but should be:

  C   R 232 + 8 [0]
  C   R 240 + 8 [0]
  C   R 248 + 8 [0]
  C   R 256 + 8 [0]

Also, the whole output summary statistics of completed requests and
final throughput will be incorrect.

This patch takes into account real completion size of the request and
fixes wrong completion accounting.

Signed-off-by: Roman Pen <r.peniaev@gmail.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: linux-kernel@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-03-05 16:11:21 -07:00
Thomas Gleixner 8f945a3325 genirq: Move kstat_incr_irqs_this_cpu() to core
No more users outside the core code. Put it into the poison
cabinet. That also gets rid of the linux/irq.h include in
kernel_stat.h

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140223212739.124207133@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-04 17:37:54 +01:00
Thomas Gleixner 792d0018a5 genirq: Add a kstat helper to increment irq stats
There is a common pattern all over the place:

      kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq));

This results in a call to core code anyway. So provide a function
which does the same thing in core.

While at it, replace the butt ugly macro with an inline.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140223212737.422068876@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-04 17:37:53 +01:00
Viresh Kumar 38edbb0b91 timer: Make sure TIMER_FLAG_MASK bits are free in allocated base
Currently we are using two lowest bit of base for internal purpose and
so they both should be zero in the allocated address. The code was
doing the right thing before this patch came in: commit c5f66e99b
(timer: Implement TIMER_IRQSAFE)

Tejun probably forgot to update this piece of code which checks if the
lowest 'n' bits are zero or not and so wasn't updated according to the
new flag. Lets use TIMER_FLAG_MASK in the calculations here.

[ tglx: Massaged changelog ]

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: tj@kernel.org
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/9144e10d7e854a0aa8a673332adec356d81a923c.1393576981.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-04 12:30:29 +01:00
Viresh Kumar c24a4a3694 timer: Check failure of timer_cpu_notify() before calling init_timer_stats()
timer_cpu_notify() should return NOTIFY_OK and nothing else. Anything else would
trigger a BUG_ON(). Return value of this routine is already checked correctly
but is done after issuing a call to init_timer_stats(). The right order would be
to check the error case first and then call init_timer_stats(). Lets do it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linaro-kernel@lists.linaro.org
Cc: fweisbec@gmail.com
Cc: tj@kernel.org
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/c439f5b6bbc2047e1662f4d523350531425bcf9d.1393576981.git.viresh.kumar@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-04 12:30:29 +01:00
Steven Rostedt (Red Hat) 7dec935a3a tracepoint: Do not waste memory on mods with no tracepoints
No reason to allocate tp_module structures for modules that have no
tracepoints. This just wastes memory.

Fixes: b75ef8b44b "Tracepoint: Dissociate from module mutex"
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-03 21:23:08 -05:00
Steven Rostedt (Red Hat) 45ab2813d4 tracing: Do not add event files for modules that fail tracepoints
If a module fails to add its tracepoints due to module tainting, do not
create the module event infrastructure in the debugfs directory. As the events
will not work and worse yet, they will silently fail, making the user wonder
why the events they enable do not display anything.

Having a warning on module load and the events not visible to the users
will make the cause of the problem much clearer.

Link: http://lkml.kernel.org/r/20140227154923.265882695@goodmis.org

Fixes: 6d723736e4 "tracing/events: add support for modules to TRACE_EVENT"
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable@vger.kernel.org # 2.6.31+
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-03 21:11:05 -05:00
Li Zefan b8dadcb58d cpuset: use rcu_read_lock() to protect task_cs()
We no longer use task_lock() to protect tsk->cgroups.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-03-03 17:28:36 -05:00
Linus Torvalds 0c0bd34a14 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Misc fixes, most of them SCHED_DEADLINE fallout"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Prevent rt_time growth to infinity
  sched/deadline: Switch CPU's presence test order
  sched/deadline: Cleanup RT leftovers from {inc/dec}_dl_migration
  sched: Fix double normalization of vruntime
2014-03-03 10:49:24 -08:00
Heiko Carstens 03b8c7b623 futex: Allow architectures to skip futex_atomic_cmpxchg_inatomic() test
If an architecture has futex_atomic_cmpxchg_inatomic() implemented and there
is no runtime check necessary, allow to skip the test within futex_init().

This allows to get rid of some code which would always give the same result,
and also allows the compiler to optimize a couple of if statements away.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/20140302120947.GA3641@osiris
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-03 11:32:08 +01:00
Rashika Kheria 64e8d20bd3 kernel: Include appropriate header file in time/timekeeping_debug.c
Include appropriate header file kernel/time/timekeeping_internal.h in
kernel/time/timekeeping_debug.c because it has prototype declaration of
function defined in kernel/time/timekeeping_debug.c.

This eliminates the following warning in
kernel/time/timekeeping_debug.c:
kernel/time/timekeeping_debug.c:68:6: warning: no previous prototype for ‘tk_debug_account_sleep_time’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-03-02 20:52:58 -08:00
Linus Torvalds 3154da34be Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc fixes, most of them on the tooling side"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Fix strict alias issue for find_first_bit
  perf tools: fix BFD detection on opensuse
  perf: Fix hotplug splat
  perf/x86: Fix event scheduling
  perf symbols: Destroy unused symsrcs
  perf annotate: Check availability of annotate when processing samples
2014-03-02 11:37:07 -06:00
Eric W. Biederman 6f285b19d0 audit: Send replies in the proper network namespace.
In perverse cases of file descriptor passing the current network
namespace of a process and the network namespace of a socket used by
that socket may differ.  Therefore use the network namespace of the
appropiate socket to ensure replies always go to the appropiate
socket.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-02-28 19:44:55 -08:00
Sebastian Capella 421a5fa1a6 PM / hibernate: use name_to_dev_t to parse resume
Use the name_to_dev_t call to parse the device name echo'd to
to /sys/power/resume.  This imitates the method used in hibernate.c
in software_resume, and allows the resume partition to be specified
using other equivalent device formats as well.  By allowing
/sys/debug/resume to accept the same syntax as the resume=device
parameter, we can parse the resume=device in the init script and
use the resume device directly from the kernel command line.

Signed-off-by: Sebastian Capella <sebastian.capella@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-01 01:02:52 +01:00
Rashika Kheria 6c5be29165 PM / wakeup: Include appropriate header file in kernel/power/wakelock.c
Include appropriate header file kernel/power/power.h in
kernel/power/wakelock.c because it has prototype declaration of function
defined in kernel/power/wakelock.c.

This eliminates the following warning in kernel/power/wakelock.c:
kernel/power/wakelock.c:34:9: warning: no previous prototype for ‘pm_show_wakelocks’ [-Wmissing-prototypes]
kernel/power/wakelock.c:184:5: warning: no previous prototype for ‘pm_wake_lock’ [-Wmissing-prototypes]
kernel/power/wakelock.c:232:5: warning: no previous prototype for ‘pm_wake_unlock’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-01 01:02:09 +01:00
Rashika Kheria 04b7346975 PM / sleep: Move prototype declaration to header file kernel/power/power.h
Move prototype declaration of function to header file
kernel/power/power.h because it is used by more than one file.

This eliminates the following warning in kernel/power/snapshot.c:

kernel/power/snapshot.c:1588:16: warning: no previous prototype for ‘swsusp_save’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-01 01:01:25 +01:00
Ingo Molnar d27c8438ee Merge branch 'timers/core' into sched/idle
Avoid heavy conflicts caused by WIP patches in drivers/cpuidle/cpuidle.c,
by merging these into a single base.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-28 13:58:25 +01:00
Eric W. Biederman 48095d991d audit: Use struct net not pid_t to remember the network namespce to reply in
In struct audit_netlink_list and audit_reply add a reference to the
network namespace of the caller and remove the userspace pid of the
caller.  This cleanly remembers the callers network namespace, and
removes a huge class of races and nasty failure modes that can occur
when attempting to relook up the callers network namespace from a
pid_t (including the caller's network namespace changing, pid
wraparound, and the pid simply not being present).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-02-28 04:04:33 -08:00
Thomas Gleixner bce1936951 Merge branch 'timers.2014.02.25a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into timers/core
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-28 11:53:48 +01:00
Ingo Molnar 62c206bd51 Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

	* Update RCU documentation.  These were posted to LKML at
	  https://lkml.org/lkml/2014/2/17/555.

	* Miscellaneous fixes.  These were posted to LKML at
	  https://lkml.org/lkml/2014/2/17/530.  Note that two of these
	  are RCU changes to other maintainer's trees: add1f09954
	  (fs) and 8857563b81 (notifer), both of which substitute
	  rcu_access_pointer() for rcu_dereference_raw().

	* Real-time latency fixes.  These were posted to LKML at
	  https://lkml.org/lkml/2014/2/17/544.

	* Torture-test changes, including refactoring of rcutorture
	  and introduction of a vestigial locktorture.  These were posted
	  to LKML at https://lkml.org/lkml/2014/2/17/599.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-02-28 08:38:30 +01:00
Rashika Kheria 864f32a52b kernel: Mark function as static in kernel/seccomp.c
Mark function as static in kernel/seccomp.c because it is not used
outside this file.

This eliminates the following warning in kernel/seccomp.c:
kernel/seccomp.c:296:6: warning: no previous prototype for ?seccomp_attach_user_filter? [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Will Drewry <wad@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2014-02-28 13:54:27 +11:00
Linus Torvalds 8d7531825c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull filesystem fixes from Jan Kara:
 "Notification, writeback, udf, quota fixes

  The notification patches are (with one exception) a fallout of my
  fsnotify rework which went into -rc1 (I've extented LTP to cover these
  cornercases to avoid similar breakage in future).

  The UDF patch is a nasty data corruption Al has recently reported,
  the revert of the writeback patch is due to possibility of violating
  sync(2) guarantees, and a quota bug can lead to corruption of quota
  files in ocfs2"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: Allocate overflow events with proper type
  fanotify: Handle overflow in case of permission events
  fsnotify: Fix detection whether overflow event is queued
  Revert "writeback: do not sync data dirtied after sync start"
  quota: Fix race between dqput() and dquot_scan_active()
  udf: Fix data corruption on file type conversion
  inotify: Fix reporting of cookies for inotify events
2014-02-27 10:37:22 -08:00
Li Zefan 99afb0fd5f cpuset: fix a race condition in __cpuset_node_allowed_softwall()
It's not safe to access task's cpuset after releasing task_lock().
Holding callback_mutex won't help.

Cc: <stable@vger.kernel.org>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-02-27 09:39:54 -05:00
Li Zefan 4729583006 cpuset: fix a locking issue in cpuset_migrate_mm()
I can trigger a lockdep warning:

  # mount -t cgroup -o cpuset xxx /cgroup
  # mkdir /cgroup/cpuset
  # mkdir /cgroup/tmp
  # echo 0 > /cgroup/tmp/cpuset.cpus
  # echo 0 > /cgroup/tmp/cpuset.mems
  # echo 1 > /cgroup/tmp/cpuset.memory_migrate
  # echo $$ > /cgroup/tmp/tasks
  # echo 1 > /cgruop/tmp/cpuset.mems

  ===============================
  [ INFO: suspicious RCU usage. ]
  3.14.0-rc1-0.1-default+ #32 Not tainted
  -------------------------------
  include/linux/cgroup.h:682 suspicious rcu_dereference_check() usage!
  ...
    [<ffffffff81582174>] dump_stack+0x72/0x86
    [<ffffffff810b8f01>] lockdep_rcu_suspicious+0x101/0x140
    [<ffffffff81105ba1>] cpuset_migrate_mm+0xb1/0xe0
  ...

We used to hold cgroup_mutex when calling cpuset_migrate_mm(), but now
we hold cpuset_mutex, which causes task_css() to complain.

This is not a false-positive but a real issue.

Holding cpuset_mutex won't prevent a task from migrating to another
cpuset, and it won't prevent the original task->cgroup from destroying
during this change.

Fixes: 5d21cc2db0 (cpuset: replace cgroup_mutex locking with cpuset internal locking)
Cc: <stable@vger.kernel.org> # 3.9+
Signed-off-by: Li Zefan <lizefan@huawei.com>
Sigend-off-by: Tejun Heo <tj@kernel.org>
2014-02-27 09:35:59 -05:00
Rashika Kheria 64be38ab03 genirq: Include missing header file in irqdomain.c
Include appropriate header file include/linux/of_irq.h in
kernel/irq/irqdomain.c because it contains prototype definition of
function define in kernel/irq/irqdomain.c.

This eliminates the following warning in kernel/irq/irqdomain.c:
kernel/irq/irqdomain.c:468:14: warning: no previous prototype for ‘irq_create_of_mapping’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Link: http://lkml.kernel.org/r/eb89aebea7ff1a46122918ac389ebecf8248be9a.1393493276.git.rashika.kheria@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-02-27 13:29:35 +01:00