Messages in this thread | | | Date | Fri, 10 Mar 2017 08:20:56 +0100 | From | Ingo Molnar <> | Subject | Re: [PATCH 1/2] x86/nmi: Optimize the check for being in the repeat_nmi code |
| |
* Andy Lutomirski <luto@amacapital.net> wrote:
> > It had nothing to do with speedup. Linus said that the current code makes the > > assembly programmer in him die a little. I want to cure that. > > One might argue that the world would be a better place if the assembly > programmer in some people died a little.
Joking aside, I'll bite: while in the kernel we try to avoid ever actually _writing_ new assembly code, assembly programming is still an invaluable skill, because it indirectly improves all the other 99% of non-assembly .c code:
- Looking at the C compiler's assembly output tells us how close the code is to optimal.
- Being able to tell whether our C abstractions are too far removed from how the compiler will map it to machine instructions is invaluable.
- Being able to shape data structures and code in a machine-friendly way.
Much would be lost if the assembly programmer went extinct and it's no accident that annotated assembly output is just two <Enter> keys away after launching 'perf top' or 'perf report'. The more developers know assembly the better, IMHO.
Thanks,
Ingo
| |