From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Auger <eric.auger@linaro.org>
Subject: Re: [RFC v2 3/6] irq: bypass: Extend skeleton for ARM forwarding
 control
Date: Mon, 06 Jul 2015 17:35:06 +0200
Message-ID: <559AA02A.6060703@linaro.org>
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To: Paolo Bonzini <pbonzini@redhat.com>, eric.auger@st.com,
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Hi Paolo,
On 07/06/2015 02:27 PM, Paolo Bonzini wrote:
> 
> 
> On 06/07/2015 14:11, Eric Auger wrote:
>> diff --git a/kernel/irq/bypass.c b/kernel/irq/bypass.c
>> index 5d0f92b..efadbe5 100644
>> --- a/kernel/irq/bypass.c
>> +++ b/kernel/irq/bypass.c
>> @@ -19,6 +19,42 @@ static LIST_HEAD(producers);
>>  static LIST_HEAD(consumers);
>>  static DEFINE_MUTEX(lock);
>>  
>> +/* lock must be hold when calling connect */
> 
> If a lock must be held while callbacks are called, you have to document
> that producers and consumers must _not_ call back into the IRQ bypass
> manager.  (If they have to, you have to document explicitly "This
> function can be called from producer and consumer callbacks" whenever
> relevant).
OK Thanks

Eric
> 
>> +static void connect(struct irq_bypass_producer *prod,
>> +		    struct irq_bypass_consumer *cons)
>> +{
>> +	if (prod->stop)
>> +		prod->stop(prod);
>> +	if (cons->stop)
>> +		cons->stop(cons);
>> +	if (prod->add_consumer)
>> +		prod->add_consumer(prod, cons);
>> +	if (cons->add_producer)
>> +		cons->add_producer(cons, prod);
>> +	if (cons->resume)
>> +		cons->resume(cons);
>> +	if (prod->resume)
>> +		prod->resume(prod);
>> +}
>> +
>> +/* lock must be hold when calling disconnect */
>> +static void disconnect(struct irq_bypass_producer *prod,
>> +		       struct irq_bypass_consumer *cons)
>> +{
>> +	if (prod->stop)
>> +		prod->stop(prod);
>> +	if (cons->stop)
>> +		cons->stop(cons);
>> +	if (cons->del_producer)
>> +		cons->del_producer(cons, prod);
>> +	if (prod->del_consumer)
>> +		prod->del_consumer(prod, cons);
>> +	if (cons->resume)
>> +		cons->resume(cons);
>> +	if (prod->resume)
>> +		prod->resume(prod);
>> +}
>> +