From: "Michael S. Tsirkin" <mst@redhat.com>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Dapeng Mi <dapeng1.mi@intel.com>, Arnd Bergmann <arnd@arndb.de>,
Bart Van Assche <bvanassche@acm.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Linux PM <linux-pm@vger.kernel.org>
Subject: Re: [PATCH] cpuidle: Move cpuidle driver forward before acpi driver in Makefile
Date: Wed, 13 Jul 2022 16:53:49 -0400 [thread overview]
Message-ID: <20220713165237-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <CAJZ5v0gsHPav5Ax6+9OMmeApqn7qdJPQmo5MMh=ba6Rtj5NnQA@mail.gmail.com>
On Wed, Jul 13, 2022 at 07:53:13PM +0200, Rafael J. Wysocki wrote:
> On Wed, Jul 13, 2022 at 10:21 AM Dapeng Mi <dapeng1.mi@intel.com> wrote:
> >
> > As long as Kconfig ACPI_PROCESSOR is enabled, ACPI_PROCESSOR would
> > select ACPI_PROCESSOR_IDLE and acpi_idle driver is enabled. But
> > in current driver loading order acpi_idle driver is always loaded
> > before cpuidle_haltpoll driver. This leads to cpuidle_hatpoll driver
> > has no chance to be loaded when it's enabled.
> >
> > Thus, move cpuidle driver forward before acpi driver and make
> > cpuidle-hatpoll driver has a chance to be run when it's enabled.
> >
> > Signed-off-by: Dapeng Mi <dapeng1.mi@intel.com>
> > ---
> > drivers/Makefile | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/Makefile b/drivers/Makefile
> > index 9a30842b22c5..921ed481b520 100644
> > --- a/drivers/Makefile
> > +++ b/drivers/Makefile
> > @@ -26,6 +26,7 @@ obj-y += idle/
> > # IPMI must come before ACPI in order to provide IPMI opregion support
> > obj-y += char/ipmi/
> >
> > +obj-$(CONFIG_CPU_IDLE) += cpuidle/
> > obj-$(CONFIG_ACPI) += acpi/
> >
> > # PnP must come after ACPI since it will eventually need to check if acpi
> > @@ -126,7 +127,6 @@ obj-$(CONFIG_EDAC) += edac/
> > obj-$(CONFIG_EISA) += eisa/
> > obj-$(CONFIG_PM_OPP) += opp/
> > obj-$(CONFIG_CPU_FREQ) += cpufreq/
> > -obj-$(CONFIG_CPU_IDLE) += cpuidle/
> > obj-y += mmc/
> > obj-y += ufs/
> > obj-$(CONFIG_MEMSTICK) += memstick/
> > --
>
> Well, this change doesn't guarantee loading haltpoll before ACPI idle.
>
> Also what if haltpoll is enabled, but the user wants ACPI idle?
Exactly. For example while on real boxes BIOS might often present broken
ACPI idle, on VMs I am guessing if ACPI is present one can assume it's
actually correct.
--
MST
next prev parent reply other threads:[~2022-07-13 20:54 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-13 8:24 [PATCH] cpuidle: Move cpuidle driver forward before acpi driver in Makefile Dapeng Mi
2022-07-13 17:53 ` Rafael J. Wysocki
2022-07-13 20:53 ` Michael S. Tsirkin [this message]
2022-07-14 2:36 ` Mi, Dapeng1
2022-07-20 3:00 ` Mi, Dapeng1
2022-07-20 10:24 ` Rafael J. Wysocki
2022-07-21 3:09 ` Mi, Dapeng1
2022-07-26 1:46 ` Mi, Dapeng1
2022-07-26 15:47 ` 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=20220713165237-mutt-send-email-mst@kernel.org \
--to=mst@redhat.com \
--cc=arnd@arndb.de \
--cc=bvanassche@acm.org \
--cc=dapeng1.mi@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=rafael@kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox