linux-kernel - Re: [PATCH v3 2/2] thermal: trip: Rework thermal_zone_set

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Date:   Wed, 29 Nov 2023 18:14:28 +0100
From:   "Rafael J. Wysocki" <rafael@...nel.org>
To:     Daniel Lezcano <daniel.lezcano@...aro.org>
Cc:     "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Linux PM <linux-pm@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        Zhang Rui <rui.zhang@...el.com>,
        Lukasz Luba <lukasz.luba@....com>
Subject: Re: [PATCH v3 2/2] thermal: trip: Rework thermal_zone_set_trip() and
 its callers

Hi Daniel,

On Wed, Nov 29, 2023 at 5:54 PM Daniel Lezcano
<daniel.lezcano@...aro.org> wrote:
>
>
> Hi Rafael,
>
> On 29/11/2023 14:38, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
> >
> > Both trip_point_temp_store() and trip_point_hyst_store() use
> > thermal_zone_set_trip() to update a given trip point, but none of them
> > actually needs to change more than one field in struct thermal_trip
> > representing it.  However, each of them effectively calls
> > __thermal_zone_get_trip() twice in a row for the same trip index value,
> > once directly and once via thermal_zone_set_trip(), which is not
> > particularly efficient, and the way in which thermal_zone_set_trip()
> > carries out the update is not particularly straightforward.
> >
> > Moreover, some checks done by them both need not go under the thermal
> > zone lock and code duplication between them can be reduced quite a bit
> > by moving the majority of logic into thermal_zone_set_trip().
> >
> > Rework all of the above functions to address the above.
>
> Please hold on before merging this change. I've some comment about it
> but I have to double check a couple of things before

That's fine, but why don't you make the comment before the double checks?