Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Ingo Molnar 

* Markus Trippelsdorf  wrote:

> On 2015.09.01 at 10:38 +0200, Ingo Molnar wrote:
> > 
> > * Markus Trippelsdorf  wrote:
> > 
> > > Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :
> > > 
> > > commit a1d8561172f369ba56d636df49a6b4d6d77e2123
> > > Merge: 3959df1dfb95 ff277d4250fe
> > > Author: Linus Torvalds 
> > > Date:   Mon Aug 31 20:26:22 2015 -0700
> > 
> > > diff --cc kernel/cpu.c
> > > index 3c91a3fdfce5,664ce5299334..82cf9dff4295
> > > --- a/kernel/cpu.c
> > > +++ b/kernel/cpu.c
> > > @@@ -394,15 -392,10 +394,15 @@@ static int _cpu_down(unsigned int cpu, 
> > >   smpboot_park_threads(cpu);
> > >   
> > >   /*
> > >  - * So now all preempt/rcu users must observe !cpu_active().
> > >  + * Prevent irq alloc/free while the dying cpu reorganizes the
> > >  + * interrupt affinities.
> > >*/
> > >  +irq_lock_sparse();
> > >   
> > >  +/*
> > >  + * So now all preempt/rcu users must observe !cpu_active().
> > >  + */
> > > - err = __stop_machine(take_cpu_down, _param, 
> > > cpumask_of(cpu));
> > > + err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > >   if (err) {
> > >   /* CPU didn't die: tell everyone.  Can't complain. */
> > >   cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
> > 
> > So the irq_lock_sparse() change is from a commit that got merged in the 
> > last merge 
> > window, which is part of v4.2:
> > 
> >   ce0d3c0a6fb1 ("genirq: Revert sparse irq locking around __cpu_up() and 
> > move it to x86 for now")
> > 
> > Could you please post the patch against Linus's latest that you have tested 
> > on 
> > your system to make it boot fine?
> > 
> > The one you posted cannot possibly build, because access to 
> > __stop_machine() is 
> > gone from cpu.c:
> 
> As I wrote in my other reply. The boot failure is nondeterministic (boot
> succeeds roughly every sixth time). So the bisection and the patch is
> just bogus (,but the boot failure is real).
> 
> Sorry.

No problem. Please let us know if any of these commits does turn out to be the 
culprit. (Which is always a possibility.)

Thanks,

Ingo
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 10:38 +0200, Ingo Molnar wrote:
> The one you posted cannot possibly build, because access to __stop_machine() 
> is 
> gone from cpu.c:
> 
> kernel/cpu.c: In function ‘_cpu_down’:
> kernel/cpu.c:404:2: error: implicit declaration of function ‘__stop_machine’ 
> [-Werror=implicit-function-declaration]
>   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));

Just to clear this up: It did build on my machine because it wasn't
compiled at all (CONFIG_HOTPLUG_CPU is not set).

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 10:38 +0200, Ingo Molnar wrote:
> 
> * Markus Trippelsdorf  wrote:
> 
> > Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :
> > 
> > commit a1d8561172f369ba56d636df49a6b4d6d77e2123
> > Merge: 3959df1dfb95 ff277d4250fe
> > Author: Linus Torvalds 
> > Date:   Mon Aug 31 20:26:22 2015 -0700
> 
> > diff --cc kernel/cpu.c
> > index 3c91a3fdfce5,664ce5299334..82cf9dff4295
> > --- a/kernel/cpu.c
> > +++ b/kernel/cpu.c
> > @@@ -394,15 -392,10 +394,15 @@@ static int _cpu_down(unsigned int cpu, 
> > smpboot_park_threads(cpu);
> >   
> > /*
> >  -   * So now all preempt/rcu users must observe !cpu_active().
> >  +   * Prevent irq alloc/free while the dying cpu reorganizes the
> >  +   * interrupt affinities.
> >  */
> >  +  irq_lock_sparse();
> >   
> >  +  /*
> >  +   * So now all preempt/rcu users must observe !cpu_active().
> >  +   */
> > -   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > +   err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > if (err) {
> > /* CPU didn't die: tell everyone.  Can't complain. */
> > cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
> 
> So the irq_lock_sparse() change is from a commit that got merged in the last 
> merge 
> window, which is part of v4.2:
> 
>   ce0d3c0a6fb1 ("genirq: Revert sparse irq locking around __cpu_up() and move 
> it to x86 for now")
> 
> Could you please post the patch against Linus's latest that you have tested 
> on 
> your system to make it boot fine?
> 
> The one you posted cannot possibly build, because access to __stop_machine() 
> is 
> gone from cpu.c:

As I wrote in my other reply. The boot failure is nondeterministic (boot
succeeds roughly every sixth time). So the bisection and the patch is
just bogus (,but the boot failure is real).

Sorry.

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 10:18 +0200, Markus Trippelsdorf wrote:
> On 2015.09.01 at 09:27 +0200, Ingo Molnar wrote:
> > 
> > * Markus Trippelsdorf  wrote:
> > 
> > > On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > > > Please pull the latest sched-core-for-linus git tree from:
> > > > 
> > > >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > > > sched-core-for-linus
> > > > 
> > > ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > > > comment in enqueue_task_dl()
> > > 
> > > Linus,
> > > 
> > > your merge (commit a1d8561172f369ba) breaks booting on my machine.
> > 
> > So could you please double check your side?
> 
> I just double checked and my git tree is clean. 
> But it could be that the boot failure is nondeterministic, so git bisect
> got off the track.

Just to confirm. The boot failure _is_ nondeterministic.
I just booted a few times in a row and it failed five times and
succeeded the sixth time.

So please ignore my bisection result and the bogus patch that I've
posted.

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Ingo Molnar 

* Markus Trippelsdorf  wrote:

> Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :
> 
> commit a1d8561172f369ba56d636df49a6b4d6d77e2123
> Merge: 3959df1dfb95 ff277d4250fe
> Author: Linus Torvalds 
> Date:   Mon Aug 31 20:26:22 2015 -0700

> diff --cc kernel/cpu.c
> index 3c91a3fdfce5,664ce5299334..82cf9dff4295
> --- a/kernel/cpu.c
> +++ b/kernel/cpu.c
> @@@ -394,15 -392,10 +394,15 @@@ static int _cpu_down(unsigned int cpu, 
>   smpboot_park_threads(cpu);
>   
>   /*
>  - * So now all preempt/rcu users must observe !cpu_active().
>  + * Prevent irq alloc/free while the dying cpu reorganizes the
>  + * interrupt affinities.
>*/
>  +irq_lock_sparse();
>   
>  +/*
>  + * So now all preempt/rcu users must observe !cpu_active().
>  + */
> - err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> + err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
>   if (err) {
>   /* CPU didn't die: tell everyone.  Can't complain. */
>   cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);

So the irq_lock_sparse() change is from a commit that got merged in the last 
merge 
window, which is part of v4.2:

  ce0d3c0a6fb1 ("genirq: Revert sparse irq locking around __cpu_up() and move 
it to x86 for now")

Could you please post the patch against Linus's latest that you have tested on 
your system to make it boot fine?

The one you posted cannot possibly build, because access to __stop_machine() is 
gone from cpu.c:

kernel/cpu.c: In function ‘_cpu_down’:
kernel/cpu.c:404:2: error: implicit declaration of function ‘__stop_machine’ 
[-Werror=implicit-function-declaration]
  err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
  ^

Thanks,

Ingo
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 09:27 +0200, Ingo Molnar wrote:
> 
> * Markus Trippelsdorf  wrote:
> 
> > On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > > Please pull the latest sched-core-for-linus git tree from:
> > > 
> > >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > > sched-core-for-linus
> > > 
> > ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > > comment in enqueue_task_dl()
> > 
> > Linus,
> > 
> > your merge (commit a1d8561172f369ba) breaks booting on my machine.
> 
> So could you please double check your side?

I just double checked and my git tree is clean. 
But it could be that the boot failure is nondeterministic, so git bisect
got off the track.

Anyway I don't have time to debug this further ATM.

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 09:27 +0200, Ingo Molnar wrote:
> 
> * Markus Trippelsdorf  wrote:
> 
> > On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > > Please pull the latest sched-core-for-linus git tree from:
> > > 
> > >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > > sched-core-for-linus
> > > 
> > ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > > comment in enqueue_task_dl()
> > 
> > Linus,
> > 
> > your merge (commit a1d8561172f369ba) breaks booting on my machine.
> 
> So I just double checked Linus's merge resolution, re-created it from 
> scratch, and 
> it looks correct. Furthermore, I resolved the conflict similarly in the past 
> and 
> this resolution had been in -tip and linux-next testing for some while.
> 
> But I noticed something weird in your revert patch:
> 
> > 
> > I wrote down the backtrace:
> > 
> > map_vsyscall
> > kvm_arch_hardware_setup
> > map_vsyscall
> > kvm_init
> > map_vsyscall
> > do_one_initcall
> > kernel_init_freeable
> > rest_init
> > kernel_init
> > ret_from_fork
> > rest_init
> > 
> > RIP: svm_hardware_setup
> > 
> > Reverting your merge resolution fixes the issue:
> > 
> > diff --git a/kernel/cpu.c b/kernel/cpu.c
> > index 82cf9dff4295..873aa0757b04 100644
> > --- a/kernel/cpu.c
> > +++ b/kernel/cpu.c
> > @@ -397,12 +397,11 @@ static int _cpu_down(unsigned int cpu, int 
> > tasks_frozen)
> >  * Prevent irq alloc/free while the dying cpu reorganizes the
> >  * interrupt affinities.
> >  */
> > -   irq_lock_sparse();
> 
> So where does this chunk come from? None of the trees nor the merge 
> resolution 
> touches this code.
> 
> Maybe you had other changes in your tree that interfered?
> 
> That missing irq_lock_sparse() might indeed break the boot. But that's not 
> something that got in there from Linus's tree AFAICS.
> 
> > /*
> >  * So now all preempt/rcu users must observe !cpu_active().
> >  */
> > -   err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > +   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > if (err) {
> > /* CPU didn't die: tell everyone.  Can't complain. */
> > cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
> 
> This change cannot possibly have built on Linus's tree, as __stop_machine() 
> got 
> unexported, it is now internal and static to kernel/stop_machine.c...
> 
> So could you please double check your side?

Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :

commit a1d8561172f369ba56d636df49a6b4d6d77e2123
Merge: 3959df1dfb95 ff277d4250fe
Author: Linus Torvalds 
Date:   Mon Aug 31 20:26:22 2015 -0700

Merge branch 'sched-core-for-linus' of 
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "The biggest change in this cycle is the rewrite of the main SMP load
  balancing metric: the CPU load/utilization.  The main goal was to make
  the metric more precise and more representative - see the changelog of
  this commit for the gory details:

9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization 
average tracking")

  It is done in a way that significantly reduces complexity of the code:

5 files changed, 249 insertions(+), 494 deletions(-)

  and the performance testing results are encouraging.  Nevertheless we
  need to keep an eye on potential regressions, since this potentially
  affects every SMP workload in existence.

  This work comes from Yuyang Du.

  Other changes:

   - SCHED_DL updates.  (Andrea Parri)

   - Simplify architecture callbacks by removing finish_arch_switch().
 (Peter Zijlstra et al)

   - cputime accounting: guarantee stime + utime == rtime.  (Peter
 Zijlstra)

   - optimize idle CPU wakeups some more - inspired by Facebook server
 loads.  (Mike Galbraith)

   - stop_machine fixes and updates.  (Oleg Nesterov)

   - Introduce the 'trace_sched_waking' tracepoint.  (Peter Zijlstra)

   - sched/numa tweaks.  (Srikar Dronamraju)

   - misc fixes and small cleanups"

* 'sched-core-for-linus' of 
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  sched/deadline: Fix comment in enqueue_task_dl()
  sched/deadline: Fix comment in push_dl_tasks()
  sched: Change the sched_class::set_cpus_allowed() calling context
  sched: Make sched_class::set_cpus_allowed() unconditional
  sched: Fix a race between __kthread_bind() and sched_setaffinity()
  sched: Ensure a task has a non-normalized vruntime when returning back to 
CFS
  sched/numa: Fix NUMA_DIRECT topology identification
  tile: Reorganize _switch_to()
  sched, sparc32: Update scheduler comments in copy_thread()
  sched: Remove finish_arch_switch()
  sched, tile: Remove finish_arch_switch
  sched, sh: Fold finish_arch_switch() into

Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Ingo Molnar 

* Markus Trippelsdorf  wrote:

> On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > Please pull the latest sched-core-for-linus git tree from:
> > 
> >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > sched-core-for-linus
> > 
> ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > comment in enqueue_task_dl()
> 
> Linus,
> 
> your merge (commit a1d8561172f369ba) breaks booting on my machine.

So I just double checked Linus's merge resolution, re-created it from scratch, 
and 
it looks correct. Furthermore, I resolved the conflict similarly in the past 
and 
this resolution had been in -tip and linux-next testing for some while.

But I noticed something weird in your revert patch:

> 
> I wrote down the backtrace:
> 
> map_vsyscall
> kvm_arch_hardware_setup
> map_vsyscall
> kvm_init
> map_vsyscall
> do_one_initcall
> kernel_init_freeable
> rest_init
> kernel_init
> ret_from_fork
> rest_init
> 
> RIP: svm_hardware_setup
> 
> Reverting your merge resolution fixes the issue:
> 
> diff --git a/kernel/cpu.c b/kernel/cpu.c
> index 82cf9dff4295..873aa0757b04 100644
> --- a/kernel/cpu.c
> +++ b/kernel/cpu.c
> @@ -397,12 +397,11 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
>* Prevent irq alloc/free while the dying cpu reorganizes the
>* interrupt affinities.
>*/
> - irq_lock_sparse();

So where does this chunk come from? None of the trees nor the merge resolution 
touches this code.

Maybe you had other changes in your tree that interfered?

That missing irq_lock_sparse() might indeed break the boot. But that's not 
something that got in there from Linus's tree AFAICS.

>   /*
>* So now all preempt/rcu users must observe !cpu_active().
>*/
> - err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> + err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
>   if (err) {
>   /* CPU didn't die: tell everyone.  Can't complain. */
>   cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);

This change cannot possibly have built on Linus's tree, as __stop_machine() got 
unexported, it is now internal and static to kernel/stop_machine.c...

So could you please double check your side?

Thanks,

Ingo
--
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> Please pull the latest sched-core-for-linus git tree from:
> 
>git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> sched-core-for-linus
> 
># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> comment in enqueue_task_dl()

Linus,

your merge (commit a1d8561172f369ba) breaks booting on my machine.

I wrote down the backtrace:

map_vsyscall
kvm_arch_hardware_setup
map_vsyscall
kvm_init
map_vsyscall
do_one_initcall
kernel_init_freeable
rest_init
kernel_init
ret_from_fork
rest_init

RIP: svm_hardware_setup

Reverting your merge resolution fixes the issue:

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 82cf9dff4295..873aa0757b04 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -397,12 +397,11 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
 * Prevent irq alloc/free while the dying cpu reorganizes the
 * interrupt affinities.
 */
-   irq_lock_sparse();
 
/*
 * So now all preempt/rcu users must observe !cpu_active().
 */
-   err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
+   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
if (err) {
/* CPU didn't die: tell everyone.  Can't complain. */
cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);

-- 
Markus
--
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Ingo Molnar 

* Markus Trippelsdorf  wrote:

> On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > Please pull the latest sched-core-for-linus git tree from:
> > 
> >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > sched-core-for-linus
> > 
> ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > comment in enqueue_task_dl()
> 
> Linus,
> 
> your merge (commit a1d8561172f369ba) breaks booting on my machine.

So I just double checked Linus's merge resolution, re-created it from scratch, 
and 
it looks correct. Furthermore, I resolved the conflict similarly in the past 
and 
this resolution had been in -tip and linux-next testing for some while.

But I noticed something weird in your revert patch:

> 
> I wrote down the backtrace:
> 
> map_vsyscall
> kvm_arch_hardware_setup
> map_vsyscall
> kvm_init
> map_vsyscall
> do_one_initcall
> kernel_init_freeable
> rest_init
> kernel_init
> ret_from_fork
> rest_init
> 
> RIP: svm_hardware_setup
> 
> Reverting your merge resolution fixes the issue:
> 
> diff --git a/kernel/cpu.c b/kernel/cpu.c
> index 82cf9dff4295..873aa0757b04 100644
> --- a/kernel/cpu.c
> +++ b/kernel/cpu.c
> @@ -397,12 +397,11 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
>* Prevent irq alloc/free while the dying cpu reorganizes the
>* interrupt affinities.
>*/
> - irq_lock_sparse();

So where does this chunk come from? None of the trees nor the merge resolution 
touches this code.

Maybe you had other changes in your tree that interfered?

That missing irq_lock_sparse() might indeed break the boot. But that's not 
something that got in there from Linus's tree AFAICS.

>   /*
>* So now all preempt/rcu users must observe !cpu_active().
>*/
> - err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> + err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
>   if (err) {
>   /* CPU didn't die: tell everyone.  Can't complain. */
>   cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);

This change cannot possibly have built on Linus's tree, as __stop_machine() got 
unexported, it is now internal and static to kernel/stop_machine.c...

So could you please double check your side?

Thanks,

Ingo
--
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> Please pull the latest sched-core-for-linus git tree from:
> 
>git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> sched-core-for-linus
> 
># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> comment in enqueue_task_dl()

Linus,

your merge (commit a1d8561172f369ba) breaks booting on my machine.

I wrote down the backtrace:

map_vsyscall
kvm_arch_hardware_setup
map_vsyscall
kvm_init
map_vsyscall
do_one_initcall
kernel_init_freeable
rest_init
kernel_init
ret_from_fork
rest_init

RIP: svm_hardware_setup

Reverting your merge resolution fixes the issue:

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 82cf9dff4295..873aa0757b04 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -397,12 +397,11 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen)
 * Prevent irq alloc/free while the dying cpu reorganizes the
 * interrupt affinities.
 */
-   irq_lock_sparse();
 
/*
 * So now all preempt/rcu users must observe !cpu_active().
 */
-   err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
+   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
if (err) {
/* CPU didn't die: tell everyone.  Can't complain. */
cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 09:27 +0200, Ingo Molnar wrote:
> 
> * Markus Trippelsdorf  wrote:
> 
> > On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > > Please pull the latest sched-core-for-linus git tree from:
> > > 
> > >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > > sched-core-for-linus
> > > 
> > ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > > comment in enqueue_task_dl()
> > 
> > Linus,
> > 
> > your merge (commit a1d8561172f369ba) breaks booting on my machine.
> 
> So I just double checked Linus's merge resolution, re-created it from 
> scratch, and 
> it looks correct. Furthermore, I resolved the conflict similarly in the past 
> and 
> this resolution had been in -tip and linux-next testing for some while.
> 
> But I noticed something weird in your revert patch:
> 
> > 
> > I wrote down the backtrace:
> > 
> > map_vsyscall
> > kvm_arch_hardware_setup
> > map_vsyscall
> > kvm_init
> > map_vsyscall
> > do_one_initcall
> > kernel_init_freeable
> > rest_init
> > kernel_init
> > ret_from_fork
> > rest_init
> > 
> > RIP: svm_hardware_setup
> > 
> > Reverting your merge resolution fixes the issue:
> > 
> > diff --git a/kernel/cpu.c b/kernel/cpu.c
> > index 82cf9dff4295..873aa0757b04 100644
> > --- a/kernel/cpu.c
> > +++ b/kernel/cpu.c
> > @@ -397,12 +397,11 @@ static int _cpu_down(unsigned int cpu, int 
> > tasks_frozen)
> >  * Prevent irq alloc/free while the dying cpu reorganizes the
> >  * interrupt affinities.
> >  */
> > -   irq_lock_sparse();
> 
> So where does this chunk come from? None of the trees nor the merge 
> resolution 
> touches this code.
> 
> Maybe you had other changes in your tree that interfered?
> 
> That missing irq_lock_sparse() might indeed break the boot. But that's not 
> something that got in there from Linus's tree AFAICS.
> 
> > /*
> >  * So now all preempt/rcu users must observe !cpu_active().
> >  */
> > -   err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > +   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > if (err) {
> > /* CPU didn't die: tell everyone.  Can't complain. */
> > cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
> 
> This change cannot possibly have built on Linus's tree, as __stop_machine() 
> got 
> unexported, it is now internal and static to kernel/stop_machine.c...
> 
> So could you please double check your side?

Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :

commit a1d8561172f369ba56d636df49a6b4d6d77e2123
Merge: 3959df1dfb95 ff277d4250fe
Author: Linus Torvalds 
Date:   Mon Aug 31 20:26:22 2015 -0700

Merge branch 'sched-core-for-linus' of 
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "The biggest change in this cycle is the rewrite of the main SMP load
  balancing metric: the CPU load/utilization.  The main goal was to make
  the metric more precise and more representative - see the changelog of
  this commit for the gory details:

9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization 
average tracking")

  It is done in a way that significantly reduces complexity of the code:

5 files changed, 249 insertions(+), 494 deletions(-)

  and the performance testing results are encouraging.  Nevertheless we
  need to keep an eye on potential regressions, since this potentially
  affects every SMP workload in existence.

  This work comes from Yuyang Du.

  Other changes:

   - SCHED_DL updates.  (Andrea Parri)

   - Simplify architecture callbacks by removing finish_arch_switch().
 (Peter Zijlstra et al)

   - cputime accounting: guarantee stime + utime == rtime.  (Peter
 Zijlstra)

   - optimize idle CPU wakeups some more - inspired by Facebook server
 loads.  (Mike Galbraith)

   - stop_machine fixes and updates.  (Oleg Nesterov)

   - Introduce the 'trace_sched_waking' tracepoint.  (Peter Zijlstra)

   - sched/numa tweaks.  (Srikar Dronamraju)

   - misc fixes and small cleanups"

* 'sched-core-for-linus' of 
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  sched/deadline: Fix comment in enqueue_task_dl()
  sched/deadline: Fix comment in push_dl_tasks()
  sched: Change the sched_class::set_cpus_allowed() calling context
  sched: Make sched_class::set_cpus_allowed() unconditional
  sched: Fix a race between __kthread_bind() and sched_setaffinity()
  sched: Ensure a task has a non-normalized vruntime when returning back to 
CFS
  sched/numa: Fix NUMA_DIRECT topology identification
  tile: Reorganize _switch_to()
  sched, sparc32: Update scheduler comments in copy_thread()
  sched: Remove finish_arch_switch()
  sched, tile: Remove finish_arch_switch

Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 09:27 +0200, Ingo Molnar wrote:
> 
> * Markus Trippelsdorf  wrote:
> 
> > On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > > Please pull the latest sched-core-for-linus git tree from:
> > > 
> > >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > > sched-core-for-linus
> > > 
> > ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > > comment in enqueue_task_dl()
> > 
> > Linus,
> > 
> > your merge (commit a1d8561172f369ba) breaks booting on my machine.
> 
> So could you please double check your side?

I just double checked and my git tree is clean. 
But it could be that the boot failure is nondeterministic, so git bisect
got off the track.

Anyway I don't have time to debug this further ATM.

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 10:18 +0200, Markus Trippelsdorf wrote:
> On 2015.09.01 at 09:27 +0200, Ingo Molnar wrote:
> > 
> > * Markus Trippelsdorf  wrote:
> > 
> > > On 2015.08.31 at 19:24 +0200, Ingo Molnar wrote:
> > > > Please pull the latest sched-core-for-linus git tree from:
> > > > 
> > > >git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
> > > > sched-core-for-linus
> > > > 
> > > ># HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix 
> > > > comment in enqueue_task_dl()
> > > 
> > > Linus,
> > > 
> > > your merge (commit a1d8561172f369ba) breaks booting on my machine.
> > 
> > So could you please double check your side?
> 
> I just double checked and my git tree is clean. 
> But it could be that the boot failure is nondeterministic, so git bisect
> got off the track.

Just to confirm. The boot failure _is_ nondeterministic.
I just booted a few times in a row and it failed five times and
succeeded the sixth time.

So please ignore my bisection result and the bogus patch that I've
posted.

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 10:38 +0200, Ingo Molnar wrote:
> 
> * Markus Trippelsdorf  wrote:
> 
> > Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :
> > 
> > commit a1d8561172f369ba56d636df49a6b4d6d77e2123
> > Merge: 3959df1dfb95 ff277d4250fe
> > Author: Linus Torvalds 
> > Date:   Mon Aug 31 20:26:22 2015 -0700
> 
> > diff --cc kernel/cpu.c
> > index 3c91a3fdfce5,664ce5299334..82cf9dff4295
> > --- a/kernel/cpu.c
> > +++ b/kernel/cpu.c
> > @@@ -394,15 -392,10 +394,15 @@@ static int _cpu_down(unsigned int cpu, 
> > smpboot_park_threads(cpu);
> >   
> > /*
> >  -   * So now all preempt/rcu users must observe !cpu_active().
> >  +   * Prevent irq alloc/free while the dying cpu reorganizes the
> >  +   * interrupt affinities.
> >  */
> >  +  irq_lock_sparse();
> >   
> >  +  /*
> >  +   * So now all preempt/rcu users must observe !cpu_active().
> >  +   */
> > -   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > +   err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > if (err) {
> > /* CPU didn't die: tell everyone.  Can't complain. */
> > cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
> 
> So the irq_lock_sparse() change is from a commit that got merged in the last 
> merge 
> window, which is part of v4.2:
> 
>   ce0d3c0a6fb1 ("genirq: Revert sparse irq locking around __cpu_up() and move 
> it to x86 for now")
> 
> Could you please post the patch against Linus's latest that you have tested 
> on 
> your system to make it boot fine?
> 
> The one you posted cannot possibly build, because access to __stop_machine() 
> is 
> gone from cpu.c:

As I wrote in my other reply. The boot failure is nondeterministic (boot
succeeds roughly every sixth time). So the bisection and the patch is
just bogus (,but the boot failure is real).

Sorry.

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Markus Trippelsdorf 
On 2015.09.01 at 10:38 +0200, Ingo Molnar wrote:
> The one you posted cannot possibly build, because access to __stop_machine() 
> is 
> gone from cpu.c:
> 
> kernel/cpu.c: In function ‘_cpu_down’:
> kernel/cpu.c:404:2: error: implicit declaration of function ‘__stop_machine’ 
> [-Werror=implicit-function-declaration]
>   err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));

Just to clear this up: It did build on my machine because it wasn't
compiled at all (CONFIG_HOTPLUG_CPU is not set).

-- 
Markus
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Ingo Molnar 

* Markus Trippelsdorf  wrote:

> Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :
> 
> commit a1d8561172f369ba56d636df49a6b4d6d77e2123
> Merge: 3959df1dfb95 ff277d4250fe
> Author: Linus Torvalds 
> Date:   Mon Aug 31 20:26:22 2015 -0700

> diff --cc kernel/cpu.c
> index 3c91a3fdfce5,664ce5299334..82cf9dff4295
> --- a/kernel/cpu.c
> +++ b/kernel/cpu.c
> @@@ -394,15 -392,10 +394,15 @@@ static int _cpu_down(unsigned int cpu, 
>   smpboot_park_threads(cpu);
>   
>   /*
>  - * So now all preempt/rcu users must observe !cpu_active().
>  + * Prevent irq alloc/free while the dying cpu reorganizes the
>  + * interrupt affinities.
>*/
>  +irq_lock_sparse();
>   
>  +/*
>  + * So now all preempt/rcu users must observe !cpu_active().
>  + */
> - err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> + err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
>   if (err) {
>   /* CPU didn't die: tell everyone.  Can't complain. */
>   cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);

So the irq_lock_sparse() change is from a commit that got merged in the last 
merge 
window, which is part of v4.2:

  ce0d3c0a6fb1 ("genirq: Revert sparse irq locking around __cpu_up() and move 
it to x86 for now")

Could you please post the patch against Linus's latest that you have tested on 
your system to make it boot fine?

The one you posted cannot possibly build, because access to __stop_machine() is 
gone from cpu.c:

kernel/cpu.c: In function ‘_cpu_down’:
kernel/cpu.c:404:2: error: implicit declaration of function ‘__stop_machine’ 
[-Werror=implicit-function-declaration]
  err = __stop_machine(take_cpu_down, _param, cpumask_of(cpu));
  ^

Thanks,

Ingo
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Re: [GIT PULL] scheduler changes for v4.3

2015-09-01 Thread Ingo Molnar 

* Markus Trippelsdorf  wrote:

> On 2015.09.01 at 10:38 +0200, Ingo Molnar wrote:
> > 
> > * Markus Trippelsdorf  wrote:
> > 
> > > Well, git show a1d8561172f369ba56d636df49a6b4d6d77e2123 :
> > > 
> > > commit a1d8561172f369ba56d636df49a6b4d6d77e2123
> > > Merge: 3959df1dfb95 ff277d4250fe
> > > Author: Linus Torvalds 
> > > Date:   Mon Aug 31 20:26:22 2015 -0700
> > 
> > > diff --cc kernel/cpu.c
> > > index 3c91a3fdfce5,664ce5299334..82cf9dff4295
> > > --- a/kernel/cpu.c
> > > +++ b/kernel/cpu.c
> > > @@@ -394,15 -392,10 +394,15 @@@ static int _cpu_down(unsigned int cpu, 
> > >   smpboot_park_threads(cpu);
> > >   
> > >   /*
> > >  - * So now all preempt/rcu users must observe !cpu_active().
> > >  + * Prevent irq alloc/free while the dying cpu reorganizes the
> > >  + * interrupt affinities.
> > >*/
> > >  +irq_lock_sparse();
> > >   
> > >  +/*
> > >  + * So now all preempt/rcu users must observe !cpu_active().
> > >  + */
> > > - err = __stop_machine(take_cpu_down, _param, 
> > > cpumask_of(cpu));
> > > + err = stop_machine(take_cpu_down, _param, cpumask_of(cpu));
> > >   if (err) {
> > >   /* CPU didn't die: tell everyone.  Can't complain. */
> > >   cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
> > 
> > So the irq_lock_sparse() change is from a commit that got merged in the 
> > last merge 
> > window, which is part of v4.2:
> > 
> >   ce0d3c0a6fb1 ("genirq: Revert sparse irq locking around __cpu_up() and 
> > move it to x86 for now")
> > 
> > Could you please post the patch against Linus's latest that you have tested 
> > on 
> > your system to make it boot fine?
> > 
> > The one you posted cannot possibly build, because access to 
> > __stop_machine() is 
> > gone from cpu.c:
> 
> As I wrote in my other reply. The boot failure is nondeterministic (boot
> succeeds roughly every sixth time). So the bisection and the patch is
> just bogus (,but the boot failure is real).
> 
> Sorry.

No problem. Please let us know if any of these commits does turn out to be the 
culprit. (Which is always a possibility.)

Thanks,

Ingo
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[GIT PULL] scheduler changes for v4.3

2015-08-31 Thread Ingo Molnar 
Linus,

Please pull the latest sched-core-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
sched-core-for-linus

   # HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix comment 
in enqueue_task_dl()

The biggest change in this cycle is the rewrite of the main SMP load balancing 
metric: the CPU load/utilization. The main goal was to make the metric more 
precise and more representative - see the changelog of this commit for the gory 
details:

  9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization average 
tracking")

It is done in a way that significantly reduces complexity of the code:

5 files changed, 249 insertions(+), 494 deletions(-)

and the performance testing results are encouraging. Nevertheless we need to 
keep 
an eye on potential regressions, since this potentially affects every SMP 
workload 
in existence.

This work comes from Yuyang Du.

Other changes:

  - SCHED_DL updates. (Andrea Parri)

  - Simplify architecture callbacks by removing finish_arch_switch().
(Peter Zijlstra et al)

  - cputime accounting: guarantee stime + utime == rtime. (Peter Zijlstra)

  - optimize idle CPU wakeups some more - inspired by Facebook server loads.
(Mike Galbraith)

  - stop_machine fixes and updates. (Oleg Nesterov)

  - Introduce the 'trace_sched_waking' tracepoint. (Peter Zijlstra)

  - sched/numa tweaks. (Srikar Dronamraju)

  - misc fixes and small cleanups

 Thanks,

Ingo

-->
Andrea Parri (2):
  sched/deadline: Fix comment in push_dl_tasks()
  sched/deadline: Fix comment in enqueue_task_dl()

Aravind Gopalakrishnan (1):
  sched/numa: Fix NUMA_DIRECT topology identification

Boqun Feng (1):
  sched/fair: Clean up the __sched_period() code

Byungchul Park (2):
  sched/fair: Fix a comment reflecting function name change
  sched: Ensure a task has a non-normalized vruntime when returning back to 
CFS

Chris Metcalf (2):
  sched, tile: Remove finish_arch_switch
  tile: Reorganize _switch_to()

Ingo Molnar (1):
  sched, sparc32: Update scheduler comments in copy_thread()

Konstantin Khlebnikov (3):
  sched/preempt, xen: Use need_resched() instead of should_resched()
  sched/preempt, powerpc, kvm: Use need_resched() instead of 
should_resched()
  sched/preempt: Fix cond_resched_lock() and cond_resched_softirq()

Lucas Stach (1):
  sched/idle: Move latency tracing stop/start calls deeper inside the idle 
loop

Markus Elfring (1):
  sched, sysctl: Delete an unnecessary check before 
unregister_sysctl_table()

Mike Galbraith (1):
  sched/fair: Beef up wake_wide()

Oleg Nesterov (5):
  stop_machine: Move 'cpu_stopper_task' and 'stop_cpus_work' into 'struct 
cpu_stopper'
  stop_machine: Don't do for_each_cpu() twice in queue_stop_cpus_work()
  stop_machine: Unexport __stop_machine()
  stop_machine: Use 'cpu_stop_fn_t' where possible
  stop_machine: Remove cpu_stop_work's from list in cpu_stop_park()

Peter Zijlstra (9):
  sched/cputime: Guarantee stime + utime == rtime
  sched: Introduce the 'trace_sched_waking' tracepoint
  sched, avr32: Remove finish_arch_switch()
  sched, score: Remove finish_arch_switch()
  sched, sh: Fold finish_arch_switch() into switch_to()
  sched: Remove finish_arch_switch()
  sched: Fix a race between __kthread_bind() and sched_setaffinity()
  sched: Make sched_class::set_cpus_allowed() unconditional
  sched: Change the sched_class::set_cpus_allowed() calling context

Ralf Baechle (1):
  sched, MIPS: Get rid of finish_arch_switch()

Srikar Dronamraju (2):
  sched/numa: Prefer NUMA hotness over cache hotness
  sched/numa: Consider 'imbalance_pct' when comparing loads in 
numa_has_capacity()

Vincent Guittot (1):
  sched/fair: Implement update_blocked_averages() for 
CONFIG_FAIR_GROUP_SCHED=n

Will Deacon (1):
  sched, arm: Remove finish_arch_switch()

Xunlei Pang (2):
  sched/rt: Remove a redundant condition from task_woken_rt()
  sched/deadline: Remove a redundant condition from task_woken_dl()

Yuyang Du (7):
  sched/fair: Avoid pulling all tasks in idle balancing
  sched/fair: Remove rq's runnable avg
  sched/fair: Rewrite runnable load and utilization average tracking
  sched/fair: Init cfs_rq's sched_entity load average
  sched/fair: Remove task and group entity load when they are dead
  sched/fair: Provide runnable_load_avg back to cfs_rq
  sched/fair: Clean up load average references

bseg...@google.com (1):
  sched/numa: Check sched_feat(NUMA) in migrate_improves_locality()


 arch/arm/include/asm/switch_to.h   |   5 +-
 arch/avr32/include/asm/switch_to.h |   7 +-
 arch/mips/include/asm/switch_to.h  |  48 +-
 arch/powerpc/kvm/book3s_hv.c   |   2 +-
 arch/score/include/asm/switch_to.h |   2 -
 arch/sh/include/asm/switch_to_32.h |   8 +-
 arch/sparc/kernel/process_32.c |  10 +-

[GIT PULL] scheduler changes for v4.3

2015-08-31 Thread Ingo Molnar 
Linus,

Please pull the latest sched-core-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
sched-core-for-linus

   # HEAD: ff277d4250fe715b219b1a3423b863418794 sched/deadline: Fix comment 
in enqueue_task_dl()

The biggest change in this cycle is the rewrite of the main SMP load balancing 
metric: the CPU load/utilization. The main goal was to make the metric more 
precise and more representative - see the changelog of this commit for the gory 
details:

  9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization average 
tracking")

It is done in a way that significantly reduces complexity of the code:

5 files changed, 249 insertions(+), 494 deletions(-)

and the performance testing results are encouraging. Nevertheless we need to 
keep 
an eye on potential regressions, since this potentially affects every SMP 
workload 
in existence.

This work comes from Yuyang Du.

Other changes:

  - SCHED_DL updates. (Andrea Parri)

  - Simplify architecture callbacks by removing finish_arch_switch().
(Peter Zijlstra et al)

  - cputime accounting: guarantee stime + utime == rtime. (Peter Zijlstra)

  - optimize idle CPU wakeups some more - inspired by Facebook server loads.
(Mike Galbraith)

  - stop_machine fixes and updates. (Oleg Nesterov)

  - Introduce the 'trace_sched_waking' tracepoint. (Peter Zijlstra)

  - sched/numa tweaks. (Srikar Dronamraju)

  - misc fixes and small cleanups

 Thanks,

Ingo

-->
Andrea Parri (2):
  sched/deadline: Fix comment in push_dl_tasks()
  sched/deadline: Fix comment in enqueue_task_dl()

Aravind Gopalakrishnan (1):
  sched/numa: Fix NUMA_DIRECT topology identification

Boqun Feng (1):
  sched/fair: Clean up the __sched_period() code

Byungchul Park (2):
  sched/fair: Fix a comment reflecting function name change
  sched: Ensure a task has a non-normalized vruntime when returning back to 
CFS

Chris Metcalf (2):
  sched, tile: Remove finish_arch_switch
  tile: Reorganize _switch_to()

Ingo Molnar (1):
  sched, sparc32: Update scheduler comments in copy_thread()

Konstantin Khlebnikov (3):
  sched/preempt, xen: Use need_resched() instead of should_resched()
  sched/preempt, powerpc, kvm: Use need_resched() instead of 
should_resched()
  sched/preempt: Fix cond_resched_lock() and cond_resched_softirq()

Lucas Stach (1):
  sched/idle: Move latency tracing stop/start calls deeper inside the idle 
loop

Markus Elfring (1):
  sched, sysctl: Delete an unnecessary check before 
unregister_sysctl_table()

Mike Galbraith (1):
  sched/fair: Beef up wake_wide()

Oleg Nesterov (5):
  stop_machine: Move 'cpu_stopper_task' and 'stop_cpus_work' into 'struct 
cpu_stopper'
  stop_machine: Don't do for_each_cpu() twice in queue_stop_cpus_work()
  stop_machine: Unexport __stop_machine()
  stop_machine: Use 'cpu_stop_fn_t' where possible
  stop_machine: Remove cpu_stop_work's from list in cpu_stop_park()

Peter Zijlstra (9):
  sched/cputime: Guarantee stime + utime == rtime
  sched: Introduce the 'trace_sched_waking' tracepoint
  sched, avr32: Remove finish_arch_switch()
  sched, score: Remove finish_arch_switch()
  sched, sh: Fold finish_arch_switch() into switch_to()
  sched: Remove finish_arch_switch()
  sched: Fix a race between __kthread_bind() and sched_setaffinity()
  sched: Make sched_class::set_cpus_allowed() unconditional
  sched: Change the sched_class::set_cpus_allowed() calling context

Ralf Baechle (1):
  sched, MIPS: Get rid of finish_arch_switch()

Srikar Dronamraju (2):
  sched/numa: Prefer NUMA hotness over cache hotness
  sched/numa: Consider 'imbalance_pct' when comparing loads in 
numa_has_capacity()

Vincent Guittot (1):
  sched/fair: Implement update_blocked_averages() for 
CONFIG_FAIR_GROUP_SCHED=n

Will Deacon (1):
  sched, arm: Remove finish_arch_switch()

Xunlei Pang (2):
  sched/rt: Remove a redundant condition from task_woken_rt()
  sched/deadline: Remove a redundant condition from task_woken_dl()

Yuyang Du (7):
  sched/fair: Avoid pulling all tasks in idle balancing
  sched/fair: Remove rq's runnable avg
  sched/fair: Rewrite runnable load and utilization average tracking
  sched/fair: Init cfs_rq's sched_entity load average
  sched/fair: Remove task and group entity load when they are dead
  sched/fair: Provide runnable_load_avg back to cfs_rq
  sched/fair: Clean up load average references

bseg...@google.com (1):
  sched/numa: Check sched_feat(NUMA) in migrate_improves_locality()


 arch/arm/include/asm/switch_to.h   |   5 +-
 arch/avr32/include/asm/switch_to.h |   7 +-
 arch/mips/include/asm/switch_to.h  |  48 +-
 arch/powerpc/kvm/book3s_hv.c   |   2 +-
 arch/score/include/asm/switch_to.h |   2 -
 arch/sh/include/asm/switch_to_32.h |   8 +-
 arch/sparc/kernel/process_32.c |  10 +-