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Date: Tue, 24 Jul 2007 12:48:13 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Adrian Bunk <bunk@stusta.de>
cc: Andrew Morton <akpm@linux-foundation.org>,
       Alexey Dobriyan <adobriyan@gmail.com>, linux-kernel@vger.kernel.org,
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Subject: Re: 2.6.23-rc1: BUG_ON in kmap_atomic_prot()
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On Tue, 24 Jul 2007, Adrian Bunk wrote:
> 
> > But do we 
> > care so much that it's worth inlining something like buffered_rmqueue()? 
> >...
> 
> Where is the problem with having buffered_rmqueue() inlined?

In this case, it was a pain to just even try to find the call chain, or 
read the asm.

I would encourage lots of kernel hackers to read the assembler code gcc 
generates. I suspect people being aware of code generation issues (and 
writing their code with that in mind) is a *much* bigger performance 
impact than gcc inlining random functions.

So maybe I'm old-fashioned and crazy, but "readability of the asm result" 
actually is a worthwhile goal. Not because we care directly, but because 
I'd like to encourage people to do it, due to the *indirect* benefits.

		Linus