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SubjectRe: [PATCH] direct-io: Deinline submit_page_section, save 5304 bytes
Date
Denys Vlasenko <dvlasenk@redhat.com> writes:

> This function compiles to 2628 bytes, 2 callsites
>
> text data bss dec hex filename
> 15197 16 0 15213 3b6d direct-io.o.before1
> 9655 16 0 9671 25c7 direct-io.o

And what is the consequence for performance? If you look at the git
history for this file, you'll find the commit that introduced the
inline:

commit ba253fbf6d3502c54e1ac8792e7ac8290a1f5b8d
Author: Andi Kleen <ak@linux.intel.com>
Date: Mon Aug 1 21:38:08 2011 -0700

direct-io: inline the complete submission path

Add inlines to all the submission path functions. While this increases
code size it also gives gcc a lot of optimization opportunities
in this critical hotpath.

...

So you're essentially undoing that work.

NAK

Cheers,
Jeff

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