(2014/05/08 15:16), Ananth N Mavinakayanahalli wrote: > On Thu, May 08, 2014 at 02:40:00PM +0900, Masami Hiramatsu wrote: >> (2014/05/08 13:47), Ananth N Mavinakayanahalli wrote: >>> On Wed, May 07, 2014 at 08:55:51PM +0900, Masami Hiramatsu wrote: >>> >>> ... >>> >>>> +#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF == 1) >>>> +/* >>>> + * On PPC64 ABIv1 the function pointer actually points to the >>>> + * function's descriptor. The first entry in the descriptor is the >>>> + * address of the function text. >>>> + */ >>>> +#define constant_function_entry(fn) (((func_descr_t *)(fn))->entry) >>>> +#else >>>> +#define constant_function_entry(fn) ((unsigned long)(fn)) >>>> +#endif >>>> + >>>> #endif /* __ASSEMBLY__ */ >>> >>> Hi Masami, >>> >>> You could just use ppc_function_entry() instead. >> >> No, I think ppc_function_entry() has two problems (on the latest -next kernel) >> >> At first, that is an inlined functions which is not applied in build time. >> Since the NOKPROBE_SYMBOL() is used outside of any functions as like as >> EXPORT_SYMBOL(), we can only use preprocessed macros. >> Next, on PPC64 ABI*v2*, ppc_function_entry() returns local function entry, >> which seems global function entry + 2 insns. I'm not sure about implementation >> of the kallsyms on PPC64 ABIv2, but I guess we need global function entry >> for kallsyms. > > ABIv2 does away with function descriptors and Anton fixed up that > routine to handle the change (the +2 is an artefact of that). Hmm, do you mean that the address +2 is the actual entry point? I'd like to know which address is same as the address shown in /proc/kallsyms. >> BTW, could you test this patch on the latest -next tree on PPC64 if possible? > > I'll test it, but it may take a bit. Thanks for your help! > > Ananth > > -- Masami HIRAMATSU Software Platform Research Dept. Linux Technology Research Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu.pt@xxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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