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Message-ID: <87627e1f-322c-a195-8ce6-8922d9787ff0@linaro.org>
Date:   Wed, 18 Jan 2023 22:01:23 +0100
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Subject: Re: [PATCH v5 0/3] Thermal ACPI APIs for generic trip points
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To:     srinivas pandruvada <srinivas.pandruvada@linux.intel.com>,
        "Zhang, Rui" <rui.zhang@intel.com>,
        "rafael@kernel.org" <rafael@kernel.org>
Cc:     "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "christophe.jaillet@wanadoo.fr" <christophe.jaillet@wanadoo.fr>,
        "linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>
References: <20230113180235.1604526-1-daniel.lezcano@linaro.org>
 <f76c13de-d250-ebc0-d234-ccb3a9ce3c28@linaro.org>
 <2627c37e07dce6b125d3fea3bf38a5f2407ad6a1.camel@intel.com>
 <5aabdd3010a02e361fbbe01f4af0e30d11f0ae6b.camel@linux.intel.com>
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 <c210542f-0a71-15f2-c58f-ec607e60b06d@linaro.org>
 <8547963350fb3bdb09a4693f0eb80c7199ab6f21.camel@linux.intel.com>
From:   Daniel Lezcano <daniel.lezcano@linaro.org>
In-Reply-To: <8547963350fb3bdb09a4693f0eb80c7199ab6f21.camel@linux.intel.com>
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On 18/01/2023 21:53, srinivas pandruvada wrote:
> On Wed, 2023-01-18 at 21:00 +0100, Daniel Lezcano wrote:
>> On 18/01/2023 20:16, srinivas pandruvada wrote:
>>
>> [ ... ]
>>
>>>>> But we'd better wait for the thermald test result from
>>>>> Srinvias.
>>>>
>>>> A quick test show that things still work with thermald and these
>>>> changes.
>>>
>>> But I have a question. In some devices trip point temperature is
>>> not
>>> static. When hardware changes, we get notification. For example
>>> INT3403_PERF_TRIP_POINT_CHANGED for INT3403 drivers.
>>> Currently get_trip can get the latest changed value. But if we
>>> preregister, we need some mechanism to update them.
>>
>> When the notification INT3403_PERF_TRIP_POINT_CHANGED happens, we
>> call
>> int340x_thermal_read_trips() which in turn updates the trip points.
>>
> 
> Not sure how we handle concurrency here when driver can freely update
> trips while thermal core is using trips.

Don't we have the same race without this patch ? The thermal core can 
call get_trip_temp() while there is an update, no ?

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