Re: [PATCH] force inlining of spinlock ops

[Ingo Molnar]

* Denys Vlasenko <dvlasenk@xxxxxxxxxx> wrote:

> With both gcc 4.7.2 and 4.9.2, sometimes gcc mysteriously doesn't inline
> very small functions we expect to be inlined. In particular,
> with this config: http://busybox.net/~vda/kernel_config
> there are more than a thousand copies of tiny spinlock-related functions:

That's an x86-64 allyesconfig AFAICS, right?

It's not mysterious, but an effect of -Os plus allowing GCC to do 
inlining heuristics:

  CONFIG_CC_OPTIMIZE_FOR_SIZE=y
  CONFIG_OPTIMIZE_INLINING=y

Does the problem go away if you unset of these config options?

Furtermore, what is the size win on x86 defconfig with these options 
set? allyesconfig has all sorts of crazy stuff enabled while defconfig 
on x86 tries to track typical distro configs.

Thanks,

	Ingo
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