On 20/01/16 15:30, Thomas Gleixner wrote: > On Tue, 19 Jan 2016, Jon Hunter wrote: >> On 18/01/16 14:47, Ulf Hansson wrote: >>>> +/* Inline functions for support of irq chips that require runtime pm */ >>>> +static inline int chip_pm_get(struct irq_desc *desc) >>> >>> Why does these new get/put functions need to be inline functions and >>> thus defined in the header file? Perhaps move them to manage.c are >>> better? >> >> They don't have to be, and so I can move them. > > Yes, please make them proper functions. The proper place for them is chip.c > >>> This won't play nicely when CONFIG_PM is unset, as pm_runtime_put() >>> would return -ENOSYS. In such cases I guess you would like to ignore >>> the error!? >> >> Ok, yes good point. > > So you need a CONFIG_PM variant and stubs which return 0 for the !PM case. > >>>> @@ -1116,6 +1116,10 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) >>>> if (!try_module_get(desc->owner)) >>>> return -ENODEV; >>>> >>>> + ret = chip_pm_get(desc); >>>> + if (ret < 0) >>>> + return ret; > > That leaks the module refcount. Ok, I will fix that. >>> I don't think using __free_irq() is the correct place to decrease the >>> runtime PM usage count. It will keep the irqchip runtime resumed even >>> if there are no irqs enabled for it. >>> >>> Instead I would rather allow the irqchip to be runtime suspended, when >>> there are no irqs enabled on it. > > Which is a no no, as you might lose interrupts that way. We disable interrupts > lazy, i.e. we do not mask them. So no, you cannot do that from > enable/disable_irq(). > >> This may appear ugly, but for something like this, we may need to have a >> separate enable/disable API, such as >> enable_irq_lazy()/disable_irq_lazy() which could be used to runtime >> suspend/resume the chip and must not be used in critical sections. > > enable_irq_lazy is a misnomer. enable_irq_pm or such might be acceptable. That's fine with me. > But before we go there I really want to see a proper use case for such > functions. Ok, that makes sense. Cheers Jon -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
