On 17/01/18 09:47, Yang, Shunyong wrote: > Hi, Thomas, > > On Wed, 2018-01-17 at 10:33 +0100, Thomas Gleixner wrote: >> On Wed, 17 Jan 2018, Yang, Shunyong wrote: >> >>> >>> Hi, Marc and Thomas, >>> >>> Thanks for your feedback. >>> >>> On Wed, 2018-01-17 at 10:18 +0100, Thomas Gleixner wrote: >>>> >>>> On Wed, 17 Jan 2018, Marc Zyngier wrote: >>>>> >>>>> >>>>> In all honesty, I'd be more inclined to remove this debug >>>>> feature >>>>> altogether, as CONFIG_GENERIC_IRQ_DEBUGFS is more complete and >>>>> more >>>>> useful. Is there any feature missing from that infrastructure >>>>> that >>>>> prevents you from using it instead? >>>>> >>>>> If the answer is "none", then I'll post a patch removing it. >>>> Wanted to do that quite some time ago and never came around to >>>> it. >>> I think they have different purpose. >>> irq_domain_mapping is an overiew of the mapping of each virq to >>> hwirq >>> and the domain it belongs. It likes a map or index of each IRQs. I >>> tend >>> to suggest to keep it. >> And how is that different from: >> >>> >>> The nodes under debugfs irq/irqs describes information of every >>> single >>> irq. >> Not at all. It contains the complete hierarchical information of each >> virq. >> > I think irq_domain_mapping can provide some high-level information in a > summary style. > For example, we can check all the IRQs connect to a specific irq chip > or irq domain.
You mean, something like this: root@flakes:/sys/kernel/debug/irq# ls -l domains/ total 0 -r--r--r-- 1 root root 0 Jan 1 1970 default -r--r--r-- 1 root root 0 Jan 1 1970 gpio@e0080000 -r--r--r-- 1 root root 0 Jan 1 1970 gpio@e1050000 -r--r--r-- 1 root root 0 Jan 1 1970 interrupt-controller@e1101000 -r--r--r-- 1 root root 0 Jan 1 1970 v2m@e0080000-2 -r--r--r-- 1 root root 0 Jan 1 1970 v2m@e0080000-3 -r--r--r-- 1 root root 0 Jan 1 1970 v2m@e0080000-4 root@flakes:/sys/kernel/debug/irq# grep -r v2m@e0080000-2 irqs/| cut -f1 -d: irqs/49 irqs/48 irqs/47 irqs/46 irqs/45 irqs/44 irqs/43 irqs/42 irqs/41 Thanks, M. -- Jazz is not dead. It just smells funny...