Nathan Studer
2013-Nov-13 21:49 UTC
[Patch] credit: Update other parameters when setting tslice_ms
From: Nate Studer <nate.studer@dornerworks.com> Add a utility function to update the rest of the timeslice accounting fields when updating the timeslice of the credit scheduler, so that capped CPUs behave correctly. Before this patch changing the timeslice to a value higher than the default would result in a domain not utilizing its full capacity and changing the timeslice to a value lower than the default would result in a domain exceeding its capacity. Signed-off-by: Nate Studer <nate.studer@dornerworks.com> --- xen/common/sched_credit.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) mode change 100644 => 100755 xen/common/sched_credit.c diff --git a/xen/common/sched_credit.c b/xen/common/sched_credit.c old mode 100644 new mode 100755 index 28dafcf..db5512e --- a/xen/common/sched_credit.c +++ b/xen/common/sched_credit.c @@ -1071,6 +1071,17 @@ csched_dom_cntl( return 0; } +static inline void +__csched_set_tslice(struct csched_private *prv, unsigned timeslice) +{ + prv->tslice_ms = timeslice; + prv->ticks_per_tslice = CSCHED_TICKS_PER_TSLICE; + if ( prv->tslice_ms < prv->ticks_per_tslice ) + prv->ticks_per_tslice = 1; + prv->tick_period_us = prv->tslice_ms * 1000 / prv->ticks_per_tslice; + prv->credits_per_tslice = CSCHED_CREDITS_PER_MSEC * prv->tslice_ms; +} + static int csched_sys_cntl(const struct scheduler *ops, struct xen_sysctl_scheduler_op *sc) @@ -1089,7 +1100,7 @@ csched_sys_cntl(const struct scheduler *ops, || params->ratelimit_us < XEN_SYSCTL_SCHED_RATELIMIT_MIN)) || MICROSECS(params->ratelimit_us) > MILLISECS(params->tslice_ms) ) goto out; - prv->tslice_ms = params->tslice_ms; + __csched_set_tslice(prv, params->tslice_ms); prv->ratelimit_us = params->ratelimit_us; /* FALLTHRU */ case XEN_SYSCTL_SCHEDOP_getinfo: @@ -1899,12 +1910,7 @@ csched_init(struct scheduler *ops) sched_credit_tslice_ms = CSCHED_DEFAULT_TSLICE_MS; } - prv->tslice_ms = sched_credit_tslice_ms; - prv->ticks_per_tslice = CSCHED_TICKS_PER_TSLICE; - if ( prv->tslice_ms < prv->ticks_per_tslice ) - prv->ticks_per_tslice = 1; - prv->tick_period_us = prv->tslice_ms * 1000 / prv->ticks_per_tslice; - prv->credits_per_tslice = CSCHED_CREDITS_PER_MSEC * prv->tslice_ms; + __csched_set_tslice(prv, sched_credit_tslice_ms); if ( MICROSECS(sched_ratelimit_us) > MILLISECS(sched_credit_tslice_ms) ) { -- 1.7.9.5
Nate Studer
2013-Nov-15 12:23 UTC
Re: [Patch] credit: Update other parameters when setting tslice_ms
CC''ing Dario, so that he has a message to reply to. On 11/13/2013 4:49 PM, Nathan Studer wrote:> From: Nate Studer <nate.studer@dornerworks.com> > > Add a utility function to update the rest of the timeslice > accounting fields when updating the timeslice of the > credit scheduler, so that capped CPUs behave correctly. > > Before this patch changing the timeslice to a value higher > than the default would result in a domain not utilizing > its full capacity and changing the timeslice to a value > lower than the default would result in a domain exceeding > its capacity. > > Signed-off-by: Nate Studer <nate.studer@dornerworks.com> > --- > xen/common/sched_credit.c | 20 +++++++++++++------- > 1 file changed, 13 insertions(+), 7 deletions(-) > mode change 100644 => 100755 xen/common/sched_credit.c > > diff --git a/xen/common/sched_credit.c b/xen/common/sched_credit.c > old mode 100644 > new mode 100755 > index 28dafcf..db5512e > --- a/xen/common/sched_credit.c > +++ b/xen/common/sched_credit.c > @@ -1071,6 +1071,17 @@ csched_dom_cntl( > return 0; > } > > +static inline void > +__csched_set_tslice(struct csched_private *prv, unsigned timeslice) > +{ > + prv->tslice_ms = timeslice; > + prv->ticks_per_tslice = CSCHED_TICKS_PER_TSLICE; > + if ( prv->tslice_ms < prv->ticks_per_tslice ) > + prv->ticks_per_tslice = 1; > + prv->tick_period_us = prv->tslice_ms * 1000 / prv->ticks_per_tslice; > + prv->credits_per_tslice = CSCHED_CREDITS_PER_MSEC * prv->tslice_ms; > +} > + > static int > csched_sys_cntl(const struct scheduler *ops, > struct xen_sysctl_scheduler_op *sc) > @@ -1089,7 +1100,7 @@ csched_sys_cntl(const struct scheduler *ops, > || params->ratelimit_us < XEN_SYSCTL_SCHED_RATELIMIT_MIN)) > || MICROSECS(params->ratelimit_us) > MILLISECS(params->tslice_ms) ) > goto out; > - prv->tslice_ms = params->tslice_ms; > + __csched_set_tslice(prv, params->tslice_ms); > prv->ratelimit_us = params->ratelimit_us; > /* FALLTHRU */ > case XEN_SYSCTL_SCHEDOP_getinfo: > @@ -1899,12 +1910,7 @@ csched_init(struct scheduler *ops) > sched_credit_tslice_ms = CSCHED_DEFAULT_TSLICE_MS; > } > > - prv->tslice_ms = sched_credit_tslice_ms; > - prv->ticks_per_tslice = CSCHED_TICKS_PER_TSLICE; > - if ( prv->tslice_ms < prv->ticks_per_tslice ) > - prv->ticks_per_tslice = 1; > - prv->tick_period_us = prv->tslice_ms * 1000 / prv->ticks_per_tslice; > - prv->credits_per_tslice = CSCHED_CREDITS_PER_MSEC * prv->tslice_ms; > + __csched_set_tslice(prv, sched_credit_tslice_ms); > > if ( MICROSECS(sched_ratelimit_us) > MILLISECS(sched_credit_tslice_ms) ) > { >
George Dunlap
2013-Nov-15 12:25 UTC
Re: [Patch] credit: Update other parameters when setting tslice_ms
On 13/11/13 21:49, Nathan Studer wrote:> From: Nate Studer <nate.studer@dornerworks.com> > > Add a utility function to update the rest of the timeslice > accounting fields when updating the timeslice of the > credit scheduler, so that capped CPUs behave correctly. > > Before this patch changing the timeslice to a value higher > than the default would result in a domain not utilizing > its full capacity and changing the timeslice to a value > lower than the default would result in a domain exceeding > its capacity. > > Signed-off-by: Nate Studer <nate.studer@dornerworks.com>Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com> And seen elsewhere: Reviewed-by: Dario Faggioli<dario.faggioli@citrix.com> (Correct me if this is the wrong patch, Dario!) Thanks, Nathan! -George
Dario Faggioli
2013-Nov-15 13:53 UTC
Re: [Patch] credit: Update other parameters when setting tslice_ms
On ven, 2013-11-15 at 12:25 +0000, George Dunlap wrote:> On 13/11/13 21:49, Nathan Studer wrote: > > From: Nate Studer <nate.studer@dornerworks.com> > > > > Add a utility function to update the rest of the timeslice > > accounting fields when updating the timeslice of the > > credit scheduler, so that capped CPUs behave correctly. > > > > Before this patch changing the timeslice to a value higher > > than the default would result in a domain not utilizing > > its full capacity and changing the timeslice to a value > > lower than the default would result in a domain exceeding > > its capacity. > > > > Signed-off-by: Nate Studer <nate.studer@dornerworks.com> > > Reviewed-by: George Dunlap <george.dunlap@eu.citrix.com> > > And seen elsewhere: > > Reviewed-by: Dario Faggioli<dario.faggioli@citrix.com> >This is perfect, thanks a lot. :-) Dario -- <<This happens because I choose it to happen!>> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel