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Message-ID: <387c126a-0106-2227-4b4a-db284965b6ca@linaro.org>
Date:   Mon, 18 Jul 2022 16:32:28 +0200
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Subject: Re: [PATCH v3 3/4] thermal/core: Build ascending ordered indexes for
 the trip points
Content-Language: en-US
To:     Zhang Rui <rui.zhang@intel.com>, rafael@kernel.org
Cc:     quic_manafm@quicinc.com, amitk@kernel.org, lukasz.luba@arm.com,
        linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220715210911.714479-1-daniel.lezcano@linaro.org>
 <20220715210911.714479-3-daniel.lezcano@linaro.org>
 <6d08939a167870ff7c1c83bb254fda5939f1d648.camel@intel.com>
From:   Daniel Lezcano <daniel.lezcano@linaro.org>
In-Reply-To: <6d08939a167870ff7c1c83bb254fda5939f1d648.camel@intel.com>
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On 18/07/2022 07:28, Zhang Rui wrote:
> On Fri, 2022-07-15 at 23:09 +0200, Daniel Lezcano wrote:
>> By convention the trips points are declared in the ascending
>> temperature order. However, no specification for the device tree,
>> ACPI
>> or documentation tells the trip points must be ordered this way.
>>
>> In the other hand, we need those to be ordered to browse them at the
>> thermal events. But if we assume they are ordered and change the code
>> based on this assumption, any platform with shuffled trip points
>> description will be broken (if they exist).
>>
>> Instead of taking the risk of breaking the existing platforms, use an
>> array of temperature ordered trip identifiers and make it available
>> for the code needing to browse the trip points in an ordered way.
>>
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

[ ... ]

>> +static void sort_trips_indexes(struct thermal_zone_device *tz)
>> +{
>> +       int i, j;
>> +
>> +       for (i = 0; i < tz->trips; i++)
>> +               tz->trips_indexes[i] = i;
>> +
>> +       for (i = 0; i < tz->trips; i++) {
>> +               for (j = i + 1; j < tz->trips; j++) {
>> +                       int t1, t2;
>> +
>> +                       tz->ops->get_trip_temp(tz, tz-
>>> trips_indexes[i], &t1);
> 
> This line can be moved to the upper loop.
> 
>> +                       tz->ops->get_trip_temp(tz, tz-
>>> trips_indexes[j], &t2);


Actually, we can not move the line up because of the swap below

>> +                       if (t1 > t2)
>> +                               swap(tz->trips_indexes[i], tz-
>>> trips_indexes[j]);
>> +               }
>> +       }
>> +}


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