Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-03-10 Thread Viresh Kumar
On Sat, Feb 15, 2014 at 7:24 AM, Kevin Hilman wrote: > From 902a2b58d61a51415457ea6768d687cdb7532eff Mon Sep 17 00:00:00 2001 > From: Kevin Hilman > Date: Fri, 14 Feb 2014 15:10:58 -0800 > Subject: [PATCH] workqueue: for NO_HZ_FULL, set default cpumask to > !tick_nohz_full_mask > > To help in ke

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-27 Thread Mike Galbraith
On Thu, 2014-02-27 at 15:43 +0100, Frederic Weisbecker wrote: > On Mon, Feb 17, 2014 at 06:26:41AM +0100, Mike Galbraith wrote: > > On Wed, 2014-02-12 at 19:23 +0100, Frederic Weisbecker wrote: > > > On Mon, Feb 10, 2014 at 10:47:29AM -0800, Paul E. McKenney wrote: > > > > On Mon, Feb 10, 2014 at

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-27 Thread Frederic Weisbecker
On Fri, Feb 14, 2014 at 03:24:35PM -0800, Kevin Hilman wrote: > Tejun Heo writes: > > > Hello, > > > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > >> +2.Use the /sys/devices/virtual/workqueue/*/cpumask sysfs files > >> + to force the WQ_SYSFS workqueues to run on

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-27 Thread Frederic Weisbecker
On Mon, Feb 17, 2014 at 06:26:41AM +0100, Mike Galbraith wrote: > On Wed, 2014-02-12 at 19:23 +0100, Frederic Weisbecker wrote: > > On Mon, Feb 10, 2014 at 10:47:29AM -0800, Paul E. McKenney wrote: > > > On Mon, Feb 10, 2014 at 06:08:31PM +0800, Lai Jiangshan wrote: > > > > Acked-by: Lai Jiangshan

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-24 Thread Mike Galbraith
On Mon, 2014-02-24 at 09:55 -0800, Kevin Hilman wrote: > Yeah, my patch only addresses the nohz_full case, but since there > doesn't seem to be any general agreemenet about the generic case, it > seems that exposing all unbound workqueues via WQ_SYSFS is the way to > go. > > Mike, looks like yo

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-24 Thread Kevin Hilman
Mike Galbraith writes: > On Sun, 2014-02-16 at 08:41 -0800, Paul E. McKenney wrote: > >> So if there is NO_HZ_FULL, you have no objection to binding workqueues to >> the timekeeping CPUs, but that you would also like some form of automatic >> binding in the !NO_HZ_FULL case. Of course, if a comm

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-18 Thread Mike Galbraith
On Mon, 2014-02-17 at 05:50 +0100, Mike Galbraith wrote: > On Sun, 2014-02-16 at 08:41 -0800, Paul E. McKenney wrote: > > So maybe start with Kevin's patch, but augment with something else for > > the !NO_HZ_FULL case? > > Sure (hm, does it work without workqueue.disable_numa ?). I took patch o

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-16 Thread Mike Galbraith
On Wed, 2014-02-12 at 19:23 +0100, Frederic Weisbecker wrote: > On Mon, Feb 10, 2014 at 10:47:29AM -0800, Paul E. McKenney wrote: > > On Mon, Feb 10, 2014 at 06:08:31PM +0800, Lai Jiangshan wrote: > > > Acked-by: Lai Jiangshan > > > > Thank you all, queued for 3.15. > > > > We should also have

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-16 Thread Mike Galbraith
On Sun, 2014-02-16 at 08:41 -0800, Paul E. McKenney wrote: > So if there is NO_HZ_FULL, you have no objection to binding workqueues to > the timekeeping CPUs, but that you would also like some form of automatic > binding in the !NO_HZ_FULL case. Of course, if a common mechanism could > serve both

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-16 Thread Paul E. McKenney
On Sat, Feb 15, 2014 at 08:36:44AM +0100, Mike Galbraith wrote: > On Fri, 2014-02-14 at 15:24 -0800, Kevin Hilman wrote: > > Tejun Heo writes: > > > > > Hello, > > > > > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > > >> +2. Use the /sys/devices/virtual/workqueue/*/c

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-14 Thread Mike Galbraith
On Fri, 2014-02-14 at 15:24 -0800, Kevin Hilman wrote: > Tejun Heo writes: > > > Hello, > > > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > >> +2.Use the /sys/devices/virtual/workqueue/*/cpumask sysfs files > >> + to force the WQ_SYSFS workqueues to run on the sp

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-14 Thread Kevin Hilman
Tejun Heo writes: > Hello, > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: >> +2. Use the /sys/devices/virtual/workqueue/*/cpumask sysfs files >> +to force the WQ_SYSFS workqueues to run on the specified set >> +of CPUs. The set of WQ_SYSFS workqueues can be displa

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-13 Thread Frederic Weisbecker
On Wed, Feb 12, 2014 at 04:33:11PM -0800, Paul E. McKenney wrote: > > Fair point! I wordsmithed it into the following. Seem reasonable? > > Thanx, Paul > > > > Docume

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Lai Jiangshan
On 02/13/2014 08:33 AM, Paul E. McKenney wrote: > On Thu, Feb 13, 2014 at 12:04:57AM +0100, Frederic Weisbecker wrote: >> On Wed, Feb 12, 2014 at 11:59:22AM -0800, Paul E. McKenney wrote: >>> On Wed, Feb 12, 2014 at 02:23:54PM -0500, Tejun Heo wrote: Hello, On Wed, Feb 12, 2014 at 11

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Paul E. McKenney
On Thu, Feb 13, 2014 at 12:04:57AM +0100, Frederic Weisbecker wrote: > On Wed, Feb 12, 2014 at 11:59:22AM -0800, Paul E. McKenney wrote: > > On Wed, Feb 12, 2014 at 02:23:54PM -0500, Tejun Heo wrote: > > > Hello, > > > > > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > > > >

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Frederic Weisbecker
On Wed, Feb 12, 2014 at 11:59:22AM -0800, Paul E. McKenney wrote: > On Wed, Feb 12, 2014 at 02:23:54PM -0500, Tejun Heo wrote: > > Hello, > > > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > > > +2. Use the /sys/devices/virtual/workqueue/*/cpumask sysfs files > > > + t

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Tejun Heo
On Wed, Feb 12, 2014 at 11:59:22AM -0800, Paul E. McKenney wrote: > Documentation/kernel-per-CPU-kthreads.txt: Workqueue affinity > > This commit documents the ability to apply CPU affinity to WQ_SYSFS > workqueues, thus offloading them from the desired worker CPUs. > > Signed-off-by: Paul E. McK

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Paul E. McKenney
On Wed, Feb 12, 2014 at 02:23:54PM -0500, Tejun Heo wrote: > Hello, > > On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > > +2. Use the /sys/devices/virtual/workqueue/*/cpumask sysfs files > > + to force the WQ_SYSFS workqueues to run on the specified set > > + of CPUs. The

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Paul E. McKenney
On Wed, Feb 12, 2014 at 07:23:38PM +0100, Frederic Weisbecker wrote: > On Mon, Feb 10, 2014 at 10:47:29AM -0800, Paul E. McKenney wrote: > > On Mon, Feb 10, 2014 at 06:08:31PM +0800, Lai Jiangshan wrote: > > > Acked-by: Lai Jiangshan > > > > Thank you all, queued for 3.15. > > > > We should also

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Tejun Heo
Hello, On Wed, Feb 12, 2014 at 11:02:41AM -0800, Paul E. McKenney wrote: > +2. Use the /sys/devices/virtual/workqueue/*/cpumask sysfs files > + to force the WQ_SYSFS workqueues to run on the specified set > + of CPUs. The set of WQ_SYSFS workqueues can be displayed using > + "ls sys

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-12 Thread Frederic Weisbecker
On Mon, Feb 10, 2014 at 10:47:29AM -0800, Paul E. McKenney wrote: > On Mon, Feb 10, 2014 at 06:08:31PM +0800, Lai Jiangshan wrote: > > Acked-by: Lai Jiangshan > > Thank you all, queued for 3.15. > > We should also have some facility for moving the SRCU workqueues to > housekeeping/timekeeping kt

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-10 Thread Paul E. McKenney
On Mon, Feb 10, 2014 at 06:08:31PM +0800, Lai Jiangshan wrote: > Acked-by: Lai Jiangshan Thank you all, queued for 3.15. We should also have some facility for moving the SRCU workqueues to housekeeping/timekeeping kthreads in the NO_HZ_FULL case. Or does this patch already have that effect?

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-02-10 Thread Lai Jiangshan
Acked-by: Lai Jiangshan On 02/01/2014 03:53 AM, Zoran Markovic wrote: > From: Shaibal Dutta > > For better use of CPU idle time, allow the scheduler to select the CPU > on which the SRCU grace period work would be scheduled. This improves > idle residency time and conserves power. > > This fun

Re: [RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-01-31 Thread Zoran Markovic
Signed-off-by: Zoran Markovic On 31 January 2014 11:53, Zoran Markovic wrote: > From: Shaibal Dutta > > For better use of CPU idle time, allow the scheduler to select the CPU > on which the SRCU grace period work would be scheduled. This improves > idle residency time and conserves power. > > T

[RFC PATCH] rcu: move SRCU grace period work to power efficient workqueue

2014-01-31 Thread Zoran Markovic
From: Shaibal Dutta For better use of CPU idle time, allow the scheduler to select the CPU on which the SRCU grace period work would be scheduled. This improves idle residency time and conserves power. This functionality is enabled when CONFIG_WQ_POWER_EFFICIENT is selected. Cc: Lai Jiangshan