On Wed, 24 Dec 2008 08:29:05 -0500, Steven Rostedt <srostedt@xxxxxxxxxx> wrote: >Yes I understand that the module and kernel code is set up differently, >PPC is pretty much the same in this aspect. I'm asking if it is easy to >change a call from the module to kernel core to another function in >kernel core? > >Question: if I have a call from the module to _mcount, how much has to >change in the set up of the registers to make it call ftrace_call >instead? Perhaps we could link in a call to ftrace_call via the tricks >in recordmcount.pl to get the info needed to make that change? The IA64 kernel uses the same gp register throughout, it is compiled with -mconstant-gp. So changing the target address from one kernel function to another only requires changing the destination address in the PLT stub, no other registers are affected. -- 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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