From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: svaidy@linux.vnet.ibm.com
Cc: linux-arch@vger.kernel.org, Gautham R Shenoy <ego@in.ibm.com>,
Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>,
linux-kernel@vger.kernel.org, Paul Mackerras <paulus@samba.org>,
arun@linux.vnet.ibm.com, Ingo Molnar <mingo@elte.hu>,
linuxppc-dev@lists.ozlabs.org,
Arjan van de Ven <arjan@infradead.org>
Subject: Re: [v7 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER.
Date: Wed, 07 Oct 2009 15:05:11 +0200 [thread overview]
Message-ID: <1254920711.26976.243.camel@twins> (raw)
In-Reply-To: <20091007112648.GC7646@dirshya.in.ibm.com>
On Wed, 2009-10-07 at 16:56 +0530, Vaidyanathan Srinivasan wrote:
> * Peter Zijlstra <a.p.zijlstra@chello.nl> [2009-10-06 20:04:39]:
>
> > On Tue, 2009-10-06 at 22:05 +0530, Arun R Bharadwaj wrote:
> >
> > > Also, the per-cpu nature of registration/unregistration of cpuidle
> > > has been maintained as ACPI needs this.
> >
> > Right, so can't we ditch that and have acpi default to the lowest
> common
> > C-state and warn when various cpus report different C-states?
>
> Hi Peter,
>
> As Arjan mentioned previously, the per-cpu registration has to stay
> for x86 for now due to legacy ACPI compatibility. Breaking that may
> break lot of existing users and we do not have a clean fallback
> method.
From what I understood some broken ass bioses report different C state
availability on different CPUs in the same SMP system.
I'm suggesting to work around that by limiting all CPUs to the subset of
C states reported on all CPUs, instead of the current mess.
I haven't heard anybody tell me why that wouldn't be possible on x86
WARNING: multiple messages have this Message-ID (diff)
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: svaidy@linux.vnet.ibm.com
Cc: Arjan van de Ven <arjan@infradead.org>,
arun@linux.vnet.ibm.com, Joel Schopp <jschopp@austin.ibm.com>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>, Ingo Molnar <mingo@elte.hu>,
Dipankar Sarma <dipankar@in.ibm.com>,
Balbir Singh <balbir@in.ibm.com>,
Gautham R Shenoy <ego@in.ibm.com>,
Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>,
linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
linux-arch@vger.kernel.org
Subject: Re: [v7 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER.
Date: Wed, 07 Oct 2009 15:05:11 +0200 [thread overview]
Message-ID: <1254920711.26976.243.camel@twins> (raw)
Message-ID: <20091007130511.C48hJsNzLimTE-ZdWeKi3UkdvFKnfTLlKJu2FMuSoTc@z> (raw)
In-Reply-To: <20091007112648.GC7646@dirshya.in.ibm.com>
On Wed, 2009-10-07 at 16:56 +0530, Vaidyanathan Srinivasan wrote:
> * Peter Zijlstra <a.p.zijlstra@chello.nl> [2009-10-06 20:04:39]:
>
> > On Tue, 2009-10-06 at 22:05 +0530, Arun R Bharadwaj wrote:
> >
> > > Also, the per-cpu nature of registration/unregistration of cpuidle
> > > has been maintained as ACPI needs this.
> >
> > Right, so can't we ditch that and have acpi default to the lowest
> common
> > C-state and warn when various cpus report different C-states?
>
> Hi Peter,
>
> As Arjan mentioned previously, the per-cpu registration has to stay
> for x86 for now due to legacy ACPI compatibility. Breaking that may
> break lot of existing users and we do not have a clean fallback
> method.
From what I understood some broken ass bioses report different C state
availability on different CPUs in the same SMP system.
I'm suggesting to work around that by limiting all CPUs to the subset of
C states reported on all CPUs, instead of the current mess.
I haven't heard anybody tell me why that wouldn't be possible on x86
WARNING: multiple messages have this Message-ID (diff)
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: svaidy@linux.vnet.ibm.com
Cc: linux-arch@vger.kernel.org, Gautham R Shenoy <ego@in.ibm.com>,
Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>,
linux-kernel@vger.kernel.org, Paul Mackerras <paulus@samba.org>,
arun@linux.vnet.ibm.com, Ingo Molnar <mingo@elte.hu>,
linuxppc-dev@lists.ozlabs.org,
Arjan van de Ven <arjan@infradead.org>
Subject: Re: [v7 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER.
Date: Wed, 07 Oct 2009 15:05:11 +0200 [thread overview]
Message-ID: <1254920711.26976.243.camel@twins> (raw)
In-Reply-To: <20091007112648.GC7646@dirshya.in.ibm.com>
On Wed, 2009-10-07 at 16:56 +0530, Vaidyanathan Srinivasan wrote:
> * Peter Zijlstra <a.p.zijlstra@chello.nl> [2009-10-06 20:04:39]:
>
> > On Tue, 2009-10-06 at 22:05 +0530, Arun R Bharadwaj wrote:
> >
> > > Also, the per-cpu nature of registration/unregistration of cpuidle
> > > has been maintained as ACPI needs this.
> >
> > Right, so can't we ditch that and have acpi default to the lowest
> common
> > C-state and warn when various cpus report different C-states?
>
> Hi Peter,
>
> As Arjan mentioned previously, the per-cpu registration has to stay
> for x86 for now due to legacy ACPI compatibility. Breaking that may
> break lot of existing users and we do not have a clean fallback
> method.
>From what I understood some broken ass bioses report different C state
availability on different CPUs in the same SMP system.
I'm suggesting to work around that by limiting all CPUs to the subset of
C states reported on all CPUs, instead of the current mess.
I haven't heard anybody tell me why that wouldn't be possible on x86
WARNING: multiple messages have this Message-ID (diff)
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: svaidy@linux.vnet.ibm.com
Cc: Arjan van de Ven <arjan@infradead.org>,
arun@linux.vnet.ibm.com, Joel Schopp <jschopp@austin.ibm.com>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>, Ingo Molnar <mingo@elte.hu>,
Dipankar Sarma <dipankar@in.ibm.com>,
Balbir Singh <balbir@in.ibm.com>,
Gautham R Shenoy <ego@in.ibm.com>,
Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>,
linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
linux-arch@vger.kernel.org
Subject: Re: [v7 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER.
Date: Wed, 07 Oct 2009 15:05:11 +0200 [thread overview]
Message-ID: <1254920711.26976.243.camel@twins> (raw)
In-Reply-To: <20091007112648.GC7646@dirshya.in.ibm.com>
On Wed, 2009-10-07 at 16:56 +0530, Vaidyanathan Srinivasan wrote:
> * Peter Zijlstra <a.p.zijlstra@chello.nl> [2009-10-06 20:04:39]:
>
> > On Tue, 2009-10-06 at 22:05 +0530, Arun R Bharadwaj wrote:
> >
> > > Also, the per-cpu nature of registration/unregistration of cpuidle
> > > has been maintained as ACPI needs this.
> >
> > Right, so can't we ditch that and have acpi default to the lowest
> common
> > C-state and warn when various cpus report different C-states?
>
> Hi Peter,
>
> As Arjan mentioned previously, the per-cpu registration has to stay
> for x86 for now due to legacy ACPI compatibility. Breaking that may
> break lot of existing users and we do not have a clean fallback
> method.
>From what I understood some broken ass bioses report different C state
availability on different CPUs in the same SMP system.
I'm suggesting to work around that by limiting all CPUs to the subset of
C states reported on all CPUs, instead of the current mess.
I haven't heard anybody tell me why that wouldn't be possible on x86
next prev parent reply other threads:[~2009-10-07 13:05 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-06 15:24 [v7 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER Arun R Bharadwaj
2009-10-06 15:24 ` Arun R Bharadwaj
2009-10-06 15:24 ` Arun R Bharadwaj
2009-10-06 15:26 ` [v7 PATCH 1/7]: cpuidle: cleanup drivers/cpuidle/cpuidle.c Arun R Bharadwaj
2009-10-06 15:26 ` Arun R Bharadwaj
2009-10-06 15:26 ` Arun R Bharadwaj
2009-10-06 15:30 ` [v7 PATCH 2/7]: cpuidle: implement a list based approach to register a set of idle routines Arun R Bharadwaj
2009-10-06 15:30 ` Arun R Bharadwaj
2009-10-06 15:30 ` Arun R Bharadwaj
2009-10-06 15:31 ` [v7 PATCH 3/7]: x86: refactor x86 idle power management code and remove all instances of pm_idle Arun R Bharadwaj
2009-10-06 15:31 ` Arun R Bharadwaj
2009-10-06 15:31 ` Arun R Bharadwaj
2009-10-07 14:45 ` Peter Zijlstra
2009-10-07 14:45 ` Peter Zijlstra
2009-10-07 16:45 ` Arun R Bharadwaj
2009-10-07 16:45 ` Arun R Bharadwaj
2009-10-08 5:54 ` Arun R Bharadwaj
2009-10-08 5:54 ` Arun R Bharadwaj
2009-10-06 15:32 ` [v7 PATCH 4/7]: POWER: enable cpuidle for POWER Arun R Bharadwaj
2009-10-06 15:32 ` Arun R Bharadwaj
2009-10-06 15:32 ` Arun R Bharadwaj
2009-10-06 15:33 ` [v7 PATCH 5/7]: pSeries/cpuidle: remove dedicate/shared idle loops, which will be moved to arch/powerpc/platforms/pseries/processor_idle.c Arun R Bharadwaj
2009-10-06 15:33 ` Arun R Bharadwaj
2009-10-06 15:33 ` Arun R Bharadwaj
2009-10-06 15:34 ` [v7 PATCH 6/7]: POWER: add a default_idle idle loop for POWER Arun R Bharadwaj
2009-10-06 15:34 ` Arun R Bharadwaj
2009-10-06 15:34 ` Arun R Bharadwaj
2009-10-06 15:35 ` [v7 PATCH 7/7]: pSeries: implement pSeries processor idle module Arun R Bharadwaj
2009-10-06 15:35 ` Arun R Bharadwaj
2009-10-06 15:35 ` Arun R Bharadwaj
2009-10-07 13:50 ` Arun R Bharadwaj
2009-10-07 13:50 ` Arun R Bharadwaj
2009-10-07 13:50 ` Arun R Bharadwaj
2009-10-06 16:35 ` [v7 PATCH 0/7]: cpuidle/x86/POWER: Cleanup idle power management code in x86, cleanup drivers/cpuidle/cpuidle.c and introduce cpuidle to POWER Arun R Bharadwaj
2009-10-06 16:35 ` Arun R Bharadwaj
2009-10-06 16:35 ` Arun R Bharadwaj
2009-10-06 18:04 ` Peter Zijlstra
2009-10-06 18:04 ` Peter Zijlstra
2009-10-07 11:26 ` Vaidyanathan Srinivasan
2009-10-07 11:26 ` Vaidyanathan Srinivasan
2009-10-07 11:47 ` Balbir Singh
2009-10-07 11:47 ` Balbir Singh
2009-10-07 13:24 ` Peter Zijlstra
2009-10-07 13:24 ` Peter Zijlstra
2009-10-07 13:05 ` Peter Zijlstra [this message]
2009-10-07 13:05 ` Peter Zijlstra
2009-10-07 13:05 ` Peter Zijlstra
2009-10-07 13:05 ` Peter Zijlstra
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