Re: [patch] uninline init_waitqueue_*() functions

Andrew Morton
2006-07-05T10:47:08Z

On Wed, 5 Jul 2006 03:44:41 -0700
Andrew Morton <akpm@osdl.org> wrote:

> On Wed, 5 Jul 2006 11:37:56 +0100
> Christoph Hellwig <hch@infradead.org> wrote:
>
> > On Wed, Jul 05, 2006 at 11:32:59AM +0200, Ingo Molnar wrote:
> > >
> > > * Andrew Morton <akpm@osdl.org> wrote:
> > >
> > > > shrinks fs/select.o by eight bytes. (More than I expected). So it
> > > > does appear to be a space win, but a pretty slim one.
> > >
> > > there are 855 calls to these functions in the allyesconfig vmlinux i
> > > did, and i measured a combined size reduction of 34791 bytes. That
> > > averages to a 40 bytes win per call site. (on i386.)
> >
> > And more importantly it's a function that's called in slowpathes per
> > definition. So saving text sounds like a good idea, how minimal it
> > may be.
> >
>
> Well yes - as I said, it's a net win. But 31 bytes per callsite seems
> weird and makes one wonder what's going on.

That's 31 bytes *savings*. After taking the hit of setting up for and
performing the function call. Which implies more than 40 bytes per callsite
with the inlined functions.