netdev - Re: [PATCH v3 1/2] pm: runtime: Simplify pm_runtime_get_if

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAJZ5v0gUpo6Shz2kQzie4XE23=fiPvD0=2yhjGptw8QbCq2SAg@mail.gmail.com>
Date: Mon, 22 Jan 2024 19:16:54 +0100
From: "Rafael J. Wysocki" <rafael@...nel.org>
To: Bjorn Helgaas <helgaas@...nel.org>
Cc: Sakari Ailus <sakari.ailus@...ux.intel.com>, linux-pm@...r.kernel.org, 
	"Rafael J. Wysocki" <rafael@...nel.org>, linux-pci@...r.kernel.org, 
	dri-devel@...ts.freedesktop.org, Jaroslav Kysela <perex@...ex.cz>, 
	Stanislaw Gruszka <stanislaw.gruszka@...ux.intel.com>, laurent.pinchart@...asonboard.com, 
	David Airlie <airlied@...il.com>, Paul Elder <paul.elder@...asonboard.com>, 
	linux-media@...r.kernel.org, 
	Thomas Hellström <thomas.hellstrom@...ux.intel.com>, 
	intel-gfx@...ts.freedesktop.org, Lucas De Marchi <lucas.demarchi@...el.com>, 
	Mark Brown <broonie@...nel.org>, Jacek Lawrynowicz <jacek.lawrynowicz@...ux.intel.com>, 
	Rodrigo Vivi <rodrigo.vivi@...el.com>, 
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>, intel-xe@...ts.freedesktop.org, 
	Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>, Alex Elder <elder@...nel.org>, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, linux-sound@...r.kernel.org, 
	Takashi Iwai <tiwai@...e.com>, Daniel Vetter <daniel@...ll.ch>, netdev@...r.kernel.org
Subject: Re: [PATCH v3 1/2] pm: runtime: Simplify pm_runtime_get_if_active() usage

On Mon, Jan 22, 2024 at 7:12 PM Bjorn Helgaas <helgaas@...nel.org> wrote:
>
> On Mon, Jan 22, 2024 at 01:41:21PM +0200, Sakari Ailus wrote:
> > There are two ways to opportunistically increment a device's runtime PM
> > usage count, calling either pm_runtime_get_if_active() or
> > pm_runtime_get_if_in_use(). The former has an argument to tell whether to
> > ignore the usage count or not, and the latter simply calls the former with
> > ign_usage_count set to false. The other users that want to ignore the
> > usage_count will have to explitly set that argument to true which is a bit
> > cumbersome.
>
> s/explitly/explicitly/
>
> > To make this function more practical to use, remove the ign_usage_count
> > argument from the function. The main implementation is renamed as
> > pm_runtime_get_conditional().
> >
> > Signed-off-by: Sakari Ailus <sakari.ailus@...ux.intel.com>
> > Reviewed-by: Alex Elder <elder@...aro.org> # drivers/net/ipa/ipa_smp2p.c
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@...asonboard.com>
> > Acked-by: Takashi Iwai <tiwai@...e.de> # sound/
> > Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@...ux.intel.com> # drivers/accel/ivpu/
> > Acked-by: Rodrigo Vivi <rodrigo.vivi@...el.com> # drivers/gpu/drm/i915/
> > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@...el.com>
>
> Acked-by: Bjorn Helgaas <bhelgaas@...gle.com> # drivers/pci/
>
> > -EXPORT_SYMBOL_GPL(pm_runtime_get_if_active);
> > +EXPORT_SYMBOL_GPL(pm_runtime_get_conditional);
>
> If pm_runtime_get_conditional() is exported, shouldn't it also be
> documented in Documentation/power/runtime_pm.rst?
>
> But I'm dubious about exporting it because
> __intel_runtime_pm_get_if_active() is the only caller, and you end up
> with the same pattern there that we have before this series in the PM
> core.  Why can't intel_runtime_pm.c be updated to use
> pm_runtime_get_if_active() or pm_runtime_get_if_in_use() directly, and
> make pm_runtime_get_conditional() static?

Sounds like a good suggestion to me.