Messages in this thread | | | Date | Fri, 9 Mar 2018 12:39:53 +0100 (CET) | From | Thomas Gleixner <> | Subject | Re: irqdesc: Why the "__ref" is needed in __irq_alloc_descs() ? |
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On Fri, 9 Mar 2018, Dou Liyang wrote: > I have a question about "__ref" in Linux kernel. > > When I looked into the __irq_alloc_descs(), I found it tagged a > "__ref" mark, but I didn't find that it referenced code or data > from init section.
See the various
#define irq_alloc_desc*
variants. That will give you enough use cases from init.
> And after I tested, seems "__ref" just puts the code into a different > section that is not checked by modpost. It does not affect the > performance whether it is tagged or not. Is it right?
Well having code in a different section can cause performance issues, but that only matters in a hotpath. irq_alloc_desc* is not performance critical at all, so nothing to worry about.
Thanks,
tglx
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