[GIT PULL] dynticks updates for 3.13

[GIT PULL] dynticks updates for 3.13

[Frederic Weisbecker]

Ingo,

Please pull the timers/core branch that can be found at:

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
	timers/core

It passed through 0-day testing. I'm proposing it for 3.13 just in case but I'm ok
as well if you think it's too late and should be delayed for 3.14

Thanks,
	Frederic
---

Frederic Weisbecker (5):
      nohz: Convert a few places to use local per cpu accesses
      context_tracking: Wrap static key check into more intuitive function name
      context_tracking: Rename context_tracking_active() to context_tracking_cpu_is_enabled()
      posix-timers: Spare workqueue if there is no full dynticks CPU to kick
      posix-timers: Fix full dynticks CPUs kick on timer rescheduling

Paul Gortmaker (1):
      trivial: fix spelling in CONTEXT_TRACKING_FORCE help text


 include/linux/context_tracking.h       | 10 ++++-----
 include/linux/context_tracking_state.h | 11 +++++++---
 include/linux/tick.h                   |  8 ++++----
 include/linux/vtime.h                  |  4 ++--
 init/Kconfig                           |  2 +-
 kernel/context_tracking.c              |  8 ++++----
 kernel/posix-cpu-timers.c              | 21 +++++++++----------
 kernel/softirq.c                       |  4 +---
 kernel/time/tick-broadcast.c           |  6 +++---
 kernel/time/tick-internal.h            |  4 ++--
 kernel/time/tick-sched.c               | 37 ++++++++++++++--------------------
 11 files changed, 54 insertions(+), 61 deletions(-)

Re: [GIT PULL] dynticks updates for 3.13

[Ingo Molnar]

* Frederic Weisbecker <fweisbec@gmail.com> wrote:

> Ingo,
> 
> Please pull the timers/core branch that can be found at:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> 	timers/core
> 
> It passed through 0-day testing. I'm proposing it for 3.13 just in case but I'm ok
> as well if you think it's too late and should be delayed for 3.14

Pulled into tip:timers/core, thanks Frederic!

In the future it would be nice to write a higher level description 
that I can put into the merge commit. I wrote this:

  Pull dynticks updates from Frederic Weisbecker: smaller fixes and 
  cleanups.

Btw., how does the bug here:

  92e73cf831ba posix-timers: Fix full dynticks CPUs kick on timer rescheduling

manifest itself to users? Is there any real bug, or suboptimal nohz 
behavior? (more wakeups than expected) This kind of information should 
really be in the changelog.

> 
> Thanks,
> 	Frederic
> ---
> 
> Frederic Weisbecker (5):
>       nohz: Convert a few places to use local per cpu accesses
>       context_tracking: Wrap static key check into more intuitive function name
>       context_tracking: Rename context_tracking_active() to context_tracking_cpu_is_enabled()
>       posix-timers: Spare workqueue if there is no full dynticks CPU to kick
>       posix-timers: Fix full dynticks CPUs kick on timer rescheduling
> 
> Paul Gortmaker (1):
>       trivial: fix spelling in CONTEXT_TRACKING_FORCE help text
> 
> 
>  include/linux/context_tracking.h       | 10 ++++-----
>  include/linux/context_tracking_state.h | 11 +++++++---
>  include/linux/tick.h                   |  8 ++++----
>  include/linux/vtime.h                  |  4 ++--
>  init/Kconfig                           |  2 +-
>  kernel/context_tracking.c              |  8 ++++----
>  kernel/posix-cpu-timers.c              | 21 +++++++++----------
>  kernel/softirq.c                       |  4 +---
>  kernel/time/tick-broadcast.c           |  6 +++---
>  kernel/time/tick-internal.h            |  4 ++--
>  kernel/time/tick-sched.c               | 37 ++++++++++++++--------------------
>  11 files changed, 54 insertions(+), 61 deletions(-)

Btw., I noticed one other detail:

-       tick_check_oneshot_broadcast(cpu);
-       tick_check_nohz(cpu);
+       tick_check_oneshot_broadcast();
+       tick_check_nohz();

it would be nice to name such functions that lose a 'cpu' argument 
with the this_cpu pattern, i.e.:

	- tick_check_oneshot_broadcast_this_cpu()
	- tick_check_nohz_this_cpu()

This makes it more obvious at a glance that they have 'current CPU' 
assumptions in them.

	Ingo

Re: [GIT PULL] dynticks updates for 3.13

[Ingo Molnar]

* Ingo Molnar <mingo@kernel.org> wrote:

> 
> * Frederic Weisbecker <fweisbec@gmail.com> wrote:
> 
> > Ingo,
> > 
> > Please pull the timers/core branch that can be found at:
> > 
> > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > 	timers/core
> > 
> > It passed through 0-day testing. I'm proposing it for 3.13 just in case but I'm ok
> > as well if you think it's too late and should be delayed for 3.14
> 
> Pulled into tip:timers/core, thanks Frederic!

Hm, I had to unpull it due to build failure:

  kernel/time/tick-sched.c:1054:2: error: too few arguments to function ‘tick_check_nohz’

I guess this means that it's better to rebase this series - at which 
point the other complaints I had could be addressed as well?

Thanks,

	Ingo

Re: [GIT PULL] dynticks updates for 3.13

[Frederic Weisbecker]

On Sat, Nov 30, 2013 at 03:11:06PM +0100, Ingo Molnar wrote:
> 
> * Ingo Molnar <mingo@kernel.org> wrote:
> 
> > 
> > * Frederic Weisbecker <fweisbec@gmail.com> wrote:
> > 
> > > Ingo,
> > > 
> > > Please pull the timers/core branch that can be found at:
> > > 
> > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > > 	timers/core
> > > 
> > > It passed through 0-day testing. I'm proposing it for 3.13 just in case but I'm ok
> > > as well if you think it's too late and should be delayed for 3.14
> > 
> > Pulled into tip:timers/core, thanks Frederic!
> 
> Hm, I had to unpull it due to build failure:
> 
>   kernel/time/tick-sched.c:1054:2: error: too few arguments to function ‘tick_check_nohz’

Aie! I realize now that Wu Fengguang's 0-day testing reported me this on the 1st version
of this patchset. Then I got distracted with other things and forgot to fix it. And it didn't
warn me on the 2nd take to avoid spamming me.

Anyway, I'll fix this and resend.

> 
> I guess this means that it's better to rebase this series - at which 
> point the other complaints I had could be addressed as well?

Yeah sure.

Thanks!

> 
> Thanks,
> 
> 	Ingo

Re: [GIT PULL] dynticks updates for 3.13

[Frederic Weisbecker]

On Sat, Nov 30, 2013 at 02:59:07PM +0100, Ingo Molnar wrote:
> 
> * Frederic Weisbecker <fweisbec@gmail.com> wrote:
> 
> > Ingo,
> > 
> > Please pull the timers/core branch that can be found at:
> > 
> > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > 	timers/core
> > 
> > It passed through 0-day testing. I'm proposing it for 3.13 just in case but I'm ok
> > as well if you think it's too late and should be delayed for 3.14
> 
> Pulled into tip:timers/core, thanks Frederic!
> 
> In the future it would be nice to write a higher level description 
> that I can put into the merge commit. I wrote this:
> 
>   Pull dynticks updates from Frederic Weisbecker: smaller fixes and 
>   cleanups.

Right, I'll add more detailed summary next times.

> 
> Btw., how does the bug here:
> 
>   92e73cf831ba posix-timers: Fix full dynticks CPUs kick on timer rescheduling
> 
> manifest itself to users? Is there any real bug, or suboptimal nohz 
> behavior? (more wakeups than expected) This kind of information should 
> really be in the changelog.

Agreed, it fixes a real bug and that's missing from the changelog, I'll make it
clearer on the next take.

> 
> > 
> > Thanks,
> > 	Frederic
> > ---
> > 
> > Frederic Weisbecker (5):
> >       nohz: Convert a few places to use local per cpu accesses
> >       context_tracking: Wrap static key check into more intuitive function name
> >       context_tracking: Rename context_tracking_active() to context_tracking_cpu_is_enabled()
> >       posix-timers: Spare workqueue if there is no full dynticks CPU to kick
> >       posix-timers: Fix full dynticks CPUs kick on timer rescheduling
> > 
> > Paul Gortmaker (1):
> >       trivial: fix spelling in CONTEXT_TRACKING_FORCE help text
> > 
> > 
> >  include/linux/context_tracking.h       | 10 ++++-----
> >  include/linux/context_tracking_state.h | 11 +++++++---
> >  include/linux/tick.h                   |  8 ++++----
> >  include/linux/vtime.h                  |  4 ++--
> >  init/Kconfig                           |  2 +-
> >  kernel/context_tracking.c              |  8 ++++----
> >  kernel/posix-cpu-timers.c              | 21 +++++++++----------
> >  kernel/softirq.c                       |  4 +---
> >  kernel/time/tick-broadcast.c           |  6 +++---
> >  kernel/time/tick-internal.h            |  4 ++--
> >  kernel/time/tick-sched.c               | 37 ++++++++++++++--------------------
> >  11 files changed, 54 insertions(+), 61 deletions(-)
> 
> Btw., I noticed one other detail:
> 
> -       tick_check_oneshot_broadcast(cpu);
> -       tick_check_nohz(cpu);
> +       tick_check_oneshot_broadcast();
> +       tick_check_nohz();
> 
> it would be nice to name such functions that lose a 'cpu' argument 
> with the this_cpu pattern, i.e.:
> 
> 	- tick_check_oneshot_broadcast_this_cpu()

Hmm, that's going to be quite a long name. But I'm ok with the whole idea, so
I'll handle that too.

> 	- tick_check_nohz_this_cpu()
> 
> This makes it more obvious at a glance that they have 'current CPU' 
> assumptions in them

Ok, thanks!