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Message-ID: <1375727977.22073.112.camel@gandalf.local.home>
Subject: Re: [RFC] gcc feature request: Moving blocks into sections
From: Steven Rostedt <rostedt@goodmis.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: LKML <linux-kernel@vger.kernel.org>, gcc <gcc@gcc.gnu.org>,
        Ingo Molnar <mingo@kernel.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        David Daney <ddaney.cavm@gmail.com>,
        Behan Webster <behanw@converseincode.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Herbert Xu <herbert@gondor.hengli.com.au>
Date: Mon, 05 Aug 2013 14:39:37 -0400
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On Mon, 2013-08-05 at 11:20 -0700, Linus Torvalds wrote:

> Of course, it would be good to optimize static_key_false() itself -
> right now those static key jumps are always five bytes, and while they
> get nopped out, it would still be nice if there was some way to have
> just a two-byte nop (turning into a short branch) *if* we can reach
> another jump that way..For small functions that would be lovely. Oh
> well.

I had patches that did exactly this:

 https://lkml.org/lkml/2012/3/8/461

But it got dropped for some reason. I don't remember why. Maybe because
of the complexity?

-- Steve


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