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Message-ID: <89f37c4a-a1fd-4806-9d05-0dc347252b4d@arm.com>
Date: Wed, 3 Apr 2024 16:03:16 +0100
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Subject: Re: [PATCH v2 1/3] thermal: gov_power_allocator: Allow binding
 without cooling devices
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To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
 linux-pm@vger.kernel.org, Nikita Travkin <nikitos.tr@gmail.com>,
 Daniel Lezcano <daniel.lezcano@linaro.org>, linux-kernel@vger.kernel.org,
 Zhang Rui <rui.zhang@intel.com>
References: <20240403-gpa-no-cooling-devs-v2-0-79bdd8439449@trvn.ru>
 <20240403-gpa-no-cooling-devs-v2-1-79bdd8439449@trvn.ru>
 <d048f863-05d1-4aeb-8904-4c09ecbe55d9@arm.com>
 <CAJZ5v0gU+a60EvKKnGsgS32YoaQE8RffwPSrbbV2APSFKgn+UA@mail.gmail.com>
From: Lukasz Luba <lukasz.luba@arm.com>
In-Reply-To: <CAJZ5v0gU+a60EvKKnGsgS32YoaQE8RffwPSrbbV2APSFKgn+UA@mail.gmail.com>
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On 4/3/24 15:41, Rafael J. Wysocki wrote:
> On Wed, Apr 3, 2024 at 2:44 PM Lukasz Luba <lukasz.luba@arm.com> wrote:
>>
>>
>>
>> On 4/3/24 12:31, Nikita Travkin via B4 Relay wrote:
>>> From: Nikita Travkin <nikita@trvn.ru>
>>>
>>> IPA was recently refactored to split out memory allocation into a
>>> separate funciton. That funciton was made to return -EINVAL if there is
>>> zero power_actors and thus no memory to allocate. This causes IPA to
>>> fail probing when the thermal zone has no attached cooling devices.
>>>
>>> Since cooling devices can attach after the thermal zone is created and
>>> the governer is attached to it, failing probe due to the lack of cooling
>>> devices is incorrect.
>>>
>>> Change the allocate_actors_buffer() to return success when there is no
>>> cooling devices present.
>>>
>>> Fixes: 912e97c67cc3 ("thermal: gov_power_allocator: Move memory allocation out of throttle()")
>>> Signed-off-by: Nikita Travkin <nikita@trvn.ru>
>>> ---
>>>    drivers/thermal/gov_power_allocator.c | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/thermal/gov_power_allocator.c b/drivers/thermal/gov_power_allocator.c
>>> index 1b17dc4c219c..ec637071ef1f 100644
>>> --- a/drivers/thermal/gov_power_allocator.c
>>> +++ b/drivers/thermal/gov_power_allocator.c
>>> @@ -606,7 +606,7 @@ static int allocate_actors_buffer(struct power_allocator_params *params,
>>>
>>>        /* There might be no cooling devices yet. */
>>>        if (!num_actors) {
>>> -             ret = -EINVAL;
>>> +             ret = 0;
>>>                goto clean_state;
>>>        }
>>>
>>>
>>
>> LGTM
>>
>> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
> 
> Applied as 6.9-rc material along with the [2/3], thanks!
> 

Thank you Rafael!