From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: tglx@linutronix.de, rafael@kernel.org, linux-pm@vger.kernel.org,
linux-kernel@vger.kernel.org, nicolas.pitre@linaro.org,
vincent.guittot@linaro.org
Subject: Re: [RFC V2 1/2] irq: Add a framework to measure interrupt timings
Date: Thu, 21 Jan 2016 10:26:44 +0100 [thread overview]
Message-ID: <56A0A454.7020606@linaro.org> (raw)
In-Reply-To: <20160120190718.GS6357@twins.programming.kicks-ass.net>
On 01/20/2016 08:07 PM, Peter Zijlstra wrote:
> On Wed, Jan 20, 2016 at 05:00:32PM +0100, Daniel Lezcano wrote:
>> +++ b/kernel/irq/handle.c
>> @@ -165,6 +165,7 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc)
>> /* Fall through to add to randomness */
>> case IRQ_HANDLED:
>> flags |= action->flags;
>> + handle_irqtiming(irq, action->dev_id);
>> break;
>>
>> default:
>
>> +++ b/kernel/irq/internals.h
>
>> +static inline void handle_irqtiming(unsigned int irq, void *dev_id)
>> +{
>> + if (__irqtimings->handler)
>> + __irqtimings->handler(irq, ktime_get(), dev_id);
>> +}
>
> Here too, ktime_get() is daft.
>
> Also, you really want to take the timestamp _before_ we call the
> handlers, not after, otherwise you mix in whatever variance exist in the
> handler duration.
Indeed.
--
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next prev parent reply other threads:[~2016-01-21 9:26 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-06 15:22 [RFC PATCH 0/2] IRQ based next prediction Daniel Lezcano
2016-01-06 15:22 ` [RFC PATCH 1/2] irq: Add a framework to measure interrupt timings Daniel Lezcano
2016-01-08 15:31 ` Thomas Gleixner
2016-01-12 11:42 ` Daniel Lezcano
2016-01-06 15:22 ` [RFC PATCH 2/2] sched: idle: IRQ based next prediction for idle period Daniel Lezcano
2016-01-06 17:40 ` Nicolas Pitre
2016-01-07 15:42 ` Daniel Lezcano
2016-01-12 19:27 ` Nicolas Pitre
2016-01-10 22:37 ` Daniel Lezcano
2016-01-10 22:46 ` Nicolas Pitre
2016-01-10 22:58 ` Daniel Lezcano
2016-01-10 23:13 ` Nicolas Pitre
2016-01-08 15:43 ` Thomas Gleixner
2016-01-12 12:41 ` Daniel Lezcano
2016-01-12 13:42 ` Thomas Gleixner
2016-01-12 14:16 ` Daniel Lezcano
2016-01-12 14:26 ` Thomas Gleixner
2016-01-12 14:52 ` Daniel Lezcano
2016-01-12 15:12 ` Thomas Gleixner
2016-01-12 16:04 ` Daniel Lezcano
2016-01-13 9:17 ` Thomas Gleixner
2016-01-18 13:21 ` Daniel Lezcano
2016-01-20 15:41 ` Thomas Gleixner
2016-01-20 16:00 ` [RFC V2 0/2] IRQ based next prediction Daniel Lezcano
2016-01-20 16:00 ` [RFC V2 1/2] irq: Add a framework to measure interrupt timings Daniel Lezcano
2016-01-20 17:55 ` Thomas Gleixner
2016-01-21 9:25 ` Daniel Lezcano
2016-01-21 10:27 ` Thomas Gleixner
2016-01-20 19:07 ` Peter Zijlstra
2016-01-20 19:57 ` Thomas Gleixner
2016-01-20 20:04 ` Nicolas Pitre
2016-01-20 20:20 ` Peter Zijlstra
2016-01-20 20:22 ` Thomas Gleixner
2016-01-21 9:50 ` Daniel Lezcano
2016-01-21 10:08 ` Peter Zijlstra
2016-01-21 12:38 ` Daniel Lezcano
2016-01-21 20:27 ` Thomas Gleixner
2016-01-21 13:52 ` Thomas Gleixner
2016-01-21 14:19 ` Daniel Lezcano
2016-01-21 18:56 ` Thomas Gleixner
2016-01-22 10:15 ` Peter Zijlstra
2016-01-21 9:26 ` Daniel Lezcano [this message]
2016-01-20 19:28 ` Peter Zijlstra
2016-01-21 9:53 ` Daniel Lezcano
2016-01-20 16:00 ` [RFC V2 2/2] sched: idle: IRQ based next prediction for idle period Daniel Lezcano
2016-01-20 17:46 ` Nicolas Pitre
2016-01-20 18:44 ` Peter Zijlstra
2016-01-21 10:03 ` Daniel Lezcano
2016-01-20 19:02 ` Peter Zijlstra
2016-01-20 19:17 ` Nicolas Pitre
2016-01-20 19:29 ` Peter Zijlstra
2016-01-20 19:34 ` Peter Zijlstra
2016-01-20 19:40 ` Peter Zijlstra
2016-01-20 19:57 ` Nicolas Pitre
2016-01-20 20:22 ` Peter Zijlstra
2016-01-20 19:49 ` Thomas Gleixner
2016-01-21 13:54 ` Daniel Lezcano
2016-01-21 14:12 ` Thomas Gleixner
2016-01-20 16:00 ` [RFC V2 0/2] IRQ based next prediction Daniel Lezcano
2016-01-20 16:00 ` [RFC V2 1/2] irq: Add a framework to measure interrupt timings Daniel Lezcano
2016-01-20 16:00 ` [RFC V2 2/2] sched: idle: IRQ based next prediction for idle period Daniel Lezcano
2016-01-20 20:14 ` Nicolas Pitre
2016-01-21 13:04 ` Daniel Lezcano
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