Hi Marc, On 2/14/23 11:56, Marc Zyngier wrote: > On Tue, 14 Feb 2023 18:30:54 +0000, > Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: >> >> >> >> On 2/13/23 00:05, Arnd Bergmann wrote: >>> On Mon, Feb 13, 2023, at 05:15, Randy Dunlap wrote: >>>> IRQ_DOMAIN is a hidden (not user visible) symbol. Users cannot set >>>> it directly thru "make *config", so drivers should select it instead >>>> of depending on it if they need it. >>>> Relying on it being set for a dependency is risky. >>>> >>>> Consistently using "select" or "depends on" can also help reduce >>>> Kconfig circular dependency issues. >>>> >>>> IRQ_DOMAIN is selected 109 times and is depended on 3 times in >>>> current linux-next. Eliminate the uses of "depends on" by >>>> converting them to "select". >>>> >>>> [PATCH 1/3] extcon: max8997: select IRQ_DOMAIN instead of depending on it >>>> [PATCH 2/3] of: OF_IRQ: select IRQ_DOMAIN instead of depending on it >>>> [PATCH 3/3] rtc: mt6397: select IRQ_DOMAIN instead of depending on it >>> >>> From a Kconfig perspective, your reasoning makes a lot of sense. >>> >>> Looking at the bigger picture, I wonder if we should just remove the >>> option and make it unconditional. It is enabled in ever architecture >>> defconfig other than alpha and sparc, and it's selected by a lot of >>> very common options such as I2C, GENERIC_MSI_IRQ, GENERIC_IRQ_CHIP, >>> and PCI_HOST_GENERIC. Enabling the option on Alpha grows the kernel >>> image from 9010KB to 9023KB, or on m68k Coldfire from 3346KB to >>> 3351KB. >> >> Marc, what do you think about this suggestion? > > Seems sensible enough to me. > > I'd also get rid of the IRQ_DOMAIN_HIERARCHY option, which is used by > a ton of things. Architectures that are not using it are either dead, > or at least terminally comatose. > > I'm half-tempted to put the following patch into -next. Maybe after > -rc1 though. And then the option can go as well. > > M. What is this patch based on? It doesn't apply cleanly to current linux-next. I made a similar patch (to linux-next) that drops the IRQ_DOMAIN_HIERARCHY option and converts its dependent code to always on. It has been built (multiple randconfigs) on all ARCHes (except hexagon), both 32-bit and 64-bit where applicable (not that it should matter here). But yes, let's plan to get one of these patches in soon (after -rc1). Thanks. -- ~Randy
