All of lore.kernel.org
 help / color / mirror / Atom feed
From: Dietmar Eggemann <dietmar.eggemann@arm.com>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>,
	Peter Zijlstra <peterz@infradead.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux PM <linux-pm@vger.kernel.org>,
	Russell King - ARM Linux <linux@arm.linux.org.uk>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Russell King <rmk+kernel@armlinux.org.uk>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	Juri Lelli <juri.lelli@arm.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Morten Rasmussen <morten.rasmussen@arm.com>
Subject: Re: [PATCH v2 02/10] cpufreq: provide data for frequency-invariant load-tracking support
Date: Tue, 11 Jul 2017 16:12:57 +0100	[thread overview]
Message-ID: <1cfe639d-6402-ea64-f502-dcf07083569f@arm.com> (raw)
In-Reply-To: <1883025.xinGhbAdMS@aspire.rjw.lan>

On 11/07/17 15:59, Rafael J. Wysocki wrote:
> On Tuesday, July 11, 2017 04:06:01 PM Dietmar Eggemann wrote:
>> On 11/07/17 07:01, Viresh Kumar wrote:
>>> On 10-07-17, 13:02, Dietmar Eggemann wrote:
>>>> Yes, I will change this. The #define approach is not really necessary
>>>> here since we're not in the scheduler hot-path and inlining is not
>>>> really required here.
>>>
>>> It would be part of scheduler hot-path for the fast-switching case, isn't it ?
>>> (I am not arguing against using weak functions, just wanted to correct above
>>> statement).
>>
>> Yes you're right here.
>>
>> But in the meantime we're convinced that cpufreq_driver_fast_switch() is
>> not the right place to call arch_set_freq_scale() since for (future)
>> arm/arm64 fast-switch driver, the return value of
>> cpufreq_driver->fast_switch() does not give us the information that the
>> frequency value did actually change.
>>
>> So we probably have to do this soemwhere in the cpufreq driver(s) to
>> support fast-switching until we have aperf/mperf like counters.
> 
> If that's the case, I'd say call arch_set_freq_scale() from drivers in all
> cases or it will get *really* confusing.

Agreed, we should do it for slow-switching drivers from within the
driver as well in this case.

  reply	other threads:[~2017-07-11 15:13 UTC|newest]

Thread overview: 62+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-06  9:49 [PATCH v2 00/10] arm, arm64: frequency- and cpu-invariant accounting support for task scheduler Dietmar Eggemann
2017-07-06  9:49 ` [PATCH v2 01/10] drivers base/arch_topology: free cpumask cpus_to_visit Dietmar Eggemann
2017-07-06 10:22   ` Viresh Kumar
2017-07-06 10:59     ` Juri Lelli
2017-07-06 11:15       ` Viresh Kumar
2017-07-07 15:50         ` Dietmar Eggemann
2017-07-06  9:49 ` [PATCH v2 02/10] cpufreq: provide data for frequency-invariant load-tracking support Dietmar Eggemann
2017-07-06 10:40   ` Viresh Kumar
2017-07-06 22:38     ` Rafael J. Wysocki
2017-07-07 16:01     ` Dietmar Eggemann
2017-07-07 16:18       ` Rafael J. Wysocki
2017-07-07 17:06         ` Dietmar Eggemann
2017-07-08 12:09           ` Rafael J. Wysocki
2017-07-10  6:54             ` Viresh Kumar
2017-07-10 12:46               ` Rafael J. Wysocki
2017-07-11  6:39                 ` Viresh Kumar
2017-07-11 15:21                   ` Dietmar Eggemann
2017-07-13 12:40                     ` Sudeep Holla
2017-07-13 13:08                       ` Dietmar Eggemann
2017-07-13 14:06                         ` Sudeep Holla
2017-07-10  9:30             ` Peter Zijlstra
2017-07-10  9:42               ` Viresh Kumar
2017-07-10 10:31                 ` Dietmar Eggemann
2017-07-10 12:02             ` Dietmar Eggemann
2017-07-11  6:01               ` Viresh Kumar
2017-07-11 15:06                 ` Dietmar Eggemann
2017-07-11 14:59                   ` Rafael J. Wysocki
2017-07-11 15:12                     ` Dietmar Eggemann [this message]
2017-07-12  4:09                   ` Viresh Kumar
2017-07-12  8:31                     ` Peter Zijlstra
2017-07-12  9:27                       ` Viresh Kumar
2017-07-12 11:14                         ` Peter Zijlstra
2017-07-12 23:13                           ` Rafael J. Wysocki
2017-07-13  7:49                             ` Peter Zijlstra
2017-07-13  8:48                             ` Viresh Kumar
2017-07-13 11:15                               ` Peter Zijlstra
2017-07-13 14:04                           ` Sudeep Holla
2017-07-13 14:42                             ` Peter Zijlstra
2017-07-13 15:00                               ` Sudeep Holla
2017-07-13 12:54                         ` Sudeep Holla
2017-07-13 12:49                     ` Sudeep Holla
2017-07-10  6:40       ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 03/10] drivers base/arch_topology: " Dietmar Eggemann
2017-07-06 10:45   ` Viresh Kumar
2017-07-07 16:51     ` Dietmar Eggemann
2017-07-06  9:49 ` [PATCH v2 04/10] arm: wire cpufreq input data for frequency-invariant accounting up to the arch Dietmar Eggemann
2017-07-06 10:42   ` Viresh Kumar
2017-07-10 15:13     ` Dietmar Eggemann
2017-07-11  6:32       ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 05/10] arm: wire frequency-invariant accounting support up to the task scheduler Dietmar Eggemann
2017-07-06 10:46   ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 06/10] arm: wire cpu-invariant " Dietmar Eggemann
2017-07-06 10:47   ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 07/10] arm64: wire cpufreq input data for frequency-invariant accounting up to the arch Dietmar Eggemann
2017-07-06 10:48   ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 08/10] arm64: wire frequency-invariant accounting support up to the task scheduler Dietmar Eggemann
2017-07-06 10:48   ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 09/10] arm64: wire cpu-invariant " Dietmar Eggemann
2017-07-06 10:49   ` Viresh Kumar
2017-07-06  9:49 ` [PATCH v2 10/10] drivers base/arch_topology: inline cpu- and frequency-invariant accounting Dietmar Eggemann
2017-07-06 10:57   ` Viresh Kumar
2017-07-10 15:17     ` Dietmar Eggemann

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1cfe639d-6402-ea64-f502-dcf07083569f@arm.com \
    --to=dietmar.eggemann@arm.com \
    --cc=catalin.marinas@arm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=juri.lelli@arm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux@arm.linux.org.uk \
    --cc=morten.rasmussen@arm.com \
    --cc=peterz@infradead.org \
    --cc=rafael@kernel.org \
    --cc=rjw@rjwysocki.net \
    --cc=rmk+kernel@armlinux.org.uk \
    --cc=vincent.guittot@linaro.org \
    --cc=viresh.kumar@linaro.org \
    --cc=will.deacon@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.