Linux-PM Archive on lore.kernel.org
 help / color / Atom feed
From: "Doug Smythies" <dsmythies@telus.net>
To: "'Rafael J. Wysocki'" <rafael@kernel.org>
Cc: "'Rafael J. Wysocki'" <rjw@rjwysocki.net>,
	"'Linux Documentation'" <linux-doc@vger.kernel.org>,
	"'LKML'" <linux-kernel@vger.kernel.org>,
	"'Peter Zijlstra'" <peterz@infradead.org>,
	"'Srinivas Pandruvada'" <srinivas.pandruvada@linux.intel.com>,
	"'Giovanni Gherdovich'" <ggherdovich@suse.cz>,
	"'Francisco Jerez'" <francisco.jerez.plata@intel.com>,
	"'Linux PM'" <linux-pm@vger.kernel.org>
Subject: RE: [PATCH] cpufreq: intel_pstate: Implement passive mode with HWP enabled
Date: Sun, 2 Aug 2020 08:17:39 -0700
Message-ID: <000b01d668e0$11508160$33f18420$@net> (raw)
In-Reply-To: <CAJZ5v0j+gziYE0t+d2bBMZ3+4Daa0L_OiX+CeTtNU8Mkv0bCBA@mail.gmail.com>

Hi Rafael,

On 2020.07.19 04:43 Rafael J. Wysocki wrote:
> On Fri, Jul 17, 2020 at 3:37 PM Doug Smythies <dsmythies@telus.net> wrote:
> > On 2020.07.16 05:08 Rafael J. Wysocki wrote:
> > > On Wed, Jul 15, 2020 at 10:39 PM Doug Smythies <dsmythies@telus.net> wrote:
> > >> On 2020.07.14 11:16 Rafael J. Wysocki wrote:
> > >> >
> > >> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > >> ...
> > >> > Since the passive mode hasn't worked with HWP at all, and it is not going to
> > >> > the default for HWP systems anyway, I don't see any drawbacks related to making
> > >> > this change, so I would consider this as 5.9 material unless there are any
> > >> > serious objections.
> > >>
> > >> Good point.
> >
> > Actually, for those users that default to passive mode upon boot,
> > this would mean they would find themselves using this.
> > Also, it isn't obvious, from the typical "what driver and what governor"
> > inquiry.
> 
> So the change in behavior is that after this patch
> intel_pstate=passive doesn't imply no_hwp any more.
> 
> That's a very minor difference though and I'm not aware of any adverse
> effects it can cause on HWP systems anyway.

My point was, that it will now default to something where
testing has not been completed.

> The "what governor" is straightforward in the passive mode: that's
> whatever cpufreq governor has been selected.

I think you might have missed my point.
From the normal methods of inquiry one does not know
if HWP is being used or not. Why? Because with
or without HWP one gets the same answers under:

/sys/devices/system/cpu/cpu*/cpufreq/scaling_driver
/sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

... Doug



  reply index

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-14 18:16 Rafael J. Wysocki
2020-07-15  0:09 ` Francisco Jerez
2020-07-15 12:04   ` Rafael J. Wysocki
2020-07-15 21:35     ` Francisco Jerez
2020-07-16  1:14       ` Srinivas Pandruvada
2020-07-16 14:33         ` Rafael J. Wysocki
2020-07-16 14:32       ` Rafael J. Wysocki
2020-07-17  0:21         ` Francisco Jerez
2020-07-19 19:06           ` Rafael J. Wysocki
2020-07-20 23:20             ` Francisco Jerez
2020-07-21 16:25               ` Srinivas Pandruvada
2020-07-21 23:14                 ` Francisco Jerez
2020-07-27 17:23                   ` Rafael J. Wysocki
2020-07-27 17:15               ` Rafael J. Wysocki
2020-07-28  2:32                 ` Francisco Jerez
2020-07-28 18:27                   ` Rafael J. Wysocki
2020-07-29  5:46                     ` Francisco Jerez
2020-07-29 17:52                       ` Rafael J. Wysocki
2020-07-30  0:49                         ` Francisco Jerez
2020-07-31 17:52                           ` Rafael J. Wysocki
2020-07-31 22:43                             ` Francisco Jerez
2020-07-28 15:41               ` Rafael J. Wysocki
2020-07-15 20:39 ` Doug Smythies
2020-07-16 12:07   ` Rafael J. Wysocki
2020-07-17 13:37     ` Doug Smythies
2020-07-19 11:42       ` Rafael J. Wysocki
2020-08-02 15:17         ` Doug Smythies [this message]
2020-08-03 17:08           ` Rafael J. Wysocki
2020-08-06  5:54             ` Doug Smythies
2020-08-06 11:39               ` Rafael J. Wysocki

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='000b01d668e0$11508160$33f18420$@net' \
    --to=dsmythies@telus.net \
    --cc=francisco.jerez.plata@intel.com \
    --cc=ggherdovich@suse.cz \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=peterz@infradead.org \
    --cc=rafael@kernel.org \
    --cc=rjw@rjwysocki.net \
    --cc=srinivas.pandruvada@linux.intel.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

Linux-PM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-pm/0 linux-pm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-pm linux-pm/ https://lore.kernel.org/linux-pm \
		linux-pm@vger.kernel.org
	public-inbox-index linux-pm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-pm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git