linux-kernel - Re: [PATCH 1/3] irq: Allow to pass the IRQF

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Date:   Thu, 22 Jun 2017 12:36:24 +0200
From:   Daniel Lezcano <daniel.lezcano@...aro.org>
To:     Mark Rutland <mark.rutland@....com>
Cc:     tglx@...utronix.de, linux-kernel@...r.kernel.org,
        Jens Axboe <axboe@...nel.dk>, Hannes Reinecke <hare@...e.com>,
        Bjorn Helgaas <bhelgaas@...gle.com>
Subject: Re: [PATCH 1/3] irq: Allow to pass the IRQF_TIMER flag with percpu
 irq request

On 22/06/2017 11:31, Mark Rutland wrote:
> Hi Daniel,
> 
> On Tue, Jun 20, 2017 at 11:28:55PM +0200, Daniel Lezcano wrote:
>> In the next changes, we track when the interrupts occur in order to
>> statistically compute when is supposed to happen the next interrupt.
>>
>> In all the interruptions, it does not make sense to store the timer interrupt
>> occurences and try to predict the next interrupt as we know the expiration
>> time.
>>
>> The request_irq() has a irq flags parameter and the timer drivers use it to
>> pass the IRQF_TIMER flag, letting us know the interrupt is coming from a timer.
>> Based on this flag, we can discard these interrupts when tracking them.
>>
>> But, the API request_percpu_irq does not allow to pass a flag, hence specifying
>> if the interrupt type is a timer.
>>
>> Add a function __request_percpu_irq() where we can specify the flags. The
>> request_percpu_irq() function is changed to be a wrapper to
>> __request_percpu_irq() passing a zero flag parameter.
>>
>> For now, in order to prevent a misusage of this parameter, only the IRQF_TIMER
>> flag (or zero) is a valid parameter to be passed to the
>> __request_percpu_irq() function.
>>
>> Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
>> Cc: Mark Rutland <mark.rutland@....com>
> 
> Sorry for leading you round the garden path on the naming.


No problem ;)



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