Re: [RFC PATCH 7/8] [SCTP]: uninline sctp_add_cmd_sf

[Vlad Yasevich]

Ilpo Järvinen wrote:
> On Wed, 20 Feb 2008, Vlad Yasevich wrote:
>
> > Ilpo Järvinen wrote:
> > > I added inline to sctp_add_cmd and appropriate comment there to
> > > avoid adding another call into the call chain. This works at least
> > > with "gcc (GCC) 4.1.2 20070626 (Red Hat 4.1.2-13)". Alternatively,
> > > __sctp_add_cmd could be introduced to .h.
> > My only concern was performance regressions, but it looks like it
> > doesn't effect anything from the few quick runs I've made.
>
> There was one call made anyway, it's a bit hard to see how it would hurt 
> to push that BUG() deeper down (in fact, this is one of the easiest case 
> in this respect, many other cases elsewhere that need uninlining don't 
> currently make any calls with inlines).
>
> > Since we are putting sctp_add_cmd_sf() on the call stack, we might
> > as well get rid of sctp_add_cmd() and reduce it a bit more.
>
> IMHO it is definately better solution for archiving the size reduction,
> I just didn't know before that the only sctp_add_cmd call could be 
> converted.

That one was a really silly one.  The chance of not calling BUG() in
that one case was so small, that it didn't really make any sense from
the code robustness side.

> [...snip...]
> > diff --git a/net/sctp/command.c b/net/sctp/command.c
> > index bb97733..3a06513 100644
> > --- a/net/sctp/command.c
> > +++ b/net/sctp/command.c
> > @@ -51,19 +51,16 @@ int sctp_init_cmd_seq(sctp_cmd_seq_t *seq)
> >  
> >  /* Add a command to a sctp_cmd_seq_t.
> >   * Return 0 if the command sequence is full.
> > + *
> > + * Inline here is not a mistake, this way sctp_add_cmd_sf doesn't need extra
> > + * calls, size penalty is of insignificant magnitude here
>
> This won't be a necessary note anymore. :-)
>
> [...snip...]

Yeah.  If you are going to resubmit, feel free to put my Signed-off-by line.

-vlad
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