Message-ID: <51FFF015.6020803@linux.intel.com>
Date: Mon, 05 Aug 2013 11:33:57 -0700
From: "H. Peter Anvin" <hpa@linux.intel.com>
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To: Linus Torvalds <torvalds@linux-foundation.org>
CC: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>,
        gcc <gcc@gcc.gnu.org>, Ingo Molnar <mingo@kernel.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.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>
Subject: Re: [RFC] gcc feature request: Moving blocks into sections
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On 08/05/2013 11:20 AM, 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.
> 

That would definitely require gcc support.  It would be useful, but
probably requires a lot of machinery.

	-hpa


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