Messages in this thread | | | From | Roland McGrath <> | Subject | Re: IO space memcpy support for userspace. | Date | Fri, 5 Dec 2008 12:27:46 -0800 (PST) |
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There is never going to be something in memcpy that makes any magical kernel calls to find out about an address. That's just loony, sorry. memcpy is inlined away by the compiler in good cases. It's like you'd asked for "*ptr" to have magical constraints by the compiler generating code to ask the kernel if "ptr" is a special address. Uh, really?
If you can think of an efficient way to determine it and do what you need, then you could write optimized routines that do that in the vDSO perhaps.
Thanks, Roland
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