linux-toradex.git/include/linux/sched/isolation.h, branch v5.1-rc1

sched: Fix various typos in comments

2018-12-03T10:55:42+00:00

Go over the scheduler source code and fix common typos
in comments - and a typo in an actual variable name.

No change in functionality intended.

Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Linus Torvalds 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Isolate workqueues when "nohz_full=" is set

2018-02-21T08:49:08+00:00

As we prepare for offloading the residual 1hz scheduler ticks to
workqueue, let's affine those to housekeepers so that they don't
interrupt the CPUs that don't want to be disturbed.

Signed-off-by: Frederic Weisbecker 
Reviewed-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1519186649-3242-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Move isolcpus= handling to the housekeeping code

2017-10-27T07:55:30+00:00

We want to centralize the isolation features, to be done by the housekeeping
subsystem and scheduler domain isolation is a significant part of it.

No intended behaviour change, we just reuse the housekeeping cpumask
and core code.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-11-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Handle the nohz_full= parameter

2017-10-27T07:55:30+00:00

We want to centralize the isolation management, done by the housekeeping
subsystem. Therefore we need to handle the nohz_full= parameter from
there.

Since nohz_full= so far has involved unbound timers, watchdog, RCU
and tilegx NAPI isolation, we keep that default behaviour.

nohz_full= will be deprecated in the future. We want to control
the isolation features from the isolcpus= parameter.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-10-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Introduce housekeeping flags

2017-10-27T07:55:29+00:00

Before we implement isolcpus under housekeeping, we need the isolation
features to be more finegrained. For example some people want NOHZ_FULL
without the full scheduler isolation, others want full scheduler
isolation without NOHZ_FULL.

So let's cut all these isolation features piecewise, at the risk of
overcutting it right now. We can still merge some flags later if they
always make sense together.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-9-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Split out new CONFIG_CPU_ISOLATION=y config from CONFIG_NO_HZ_FULL

2017-10-27T07:55:28+00:00

Split the housekeeping config from CONFIG_NO_HZ_FULL. This way we finally
separate the isolation code from NOHZ.

Although a dependency to CONFIG_NO_HZ_FULL remains for now, while the
housekeeping code still deals with NOHZ internals.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-8-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Rename is_housekeeping_cpu() to housekeeping_cpu()

2017-10-27T07:55:28+00:00

Fit it into the housekeeping_*() namespace.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-7-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Use its own static key

2017-10-27T07:55:27+00:00

Housekeeping code still depends on the nohz_full static key. Since we want
to decouple housekeeping from NOHZ, let's create a housekeeping specific
static key.

It's mostly relevant for calls to is_housekeeping_cpu() from the scheduler.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-6-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Make the housekeeping cpumask private

2017-10-27T07:55:26+00:00

Nobody needs to access this detail. housekeeping_cpumask() already
takes care of it.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar

sched/isolation: Provide a dynamic off-case to housekeeping_any_cpu()

2017-10-27T07:55:26+00:00

housekeeping_any_cpu() doesn't handle correctly the case where
CONFIG_NO_HZ_FULL=y and no CPU is in nohz_full mode. So far no caller
needs this but let's prepare to avoid any future surprise.

Signed-off-by: Frederic Weisbecker 
Acked-by: Thomas Gleixner 
Cc: Chris Metcalf 
Cc: Christoph Lameter 
Cc: Linus Torvalds 
Cc: Luiz Capitulino 
Cc: Mike Galbraith 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Rik van Riel 
Cc: Wanpeng Li 
Link: http://lkml.kernel.org/r/1509072159-31808-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar