Date: Fri, 8 Aug 2008 20:51:23 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
To: Jeremy Fitzhardinge <jeremy@goop.org>
cc: Andi Kleen <andi@firstfloor.org>,
       Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>,
       Peter Zijlstra <peterz@infradead.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       David Miller <davem@davemloft.net>, Roland McGrath <roland@redhat.com>,
       Ulrich Drepper <drepper@redhat.com>,
       Rusty Russell <rusty@rustcorp.com.au>,
       Gregory Haskins <ghaskins@novell.com>,
       Arnaldo Carvalho de Melo <acme@redhat.com>,
       "Luis Claudio R. Goncalves" <lclaudio@uudg.org>,
       Clark Williams <williams@redhat.com>
Subject: Re: [PATCH 0/5] ftrace: to kill a daemon
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On Fri, 8 Aug 2008, Jeremy Fitzhardinge wrote:

> Steven Rostedt wrote:
> > I wish we had a true 5 byte nop. 
> 
> 0x66 0x66 0x66 0x66 0x90
> 

But I quote you:

> Unfortunately, aside from P6_NOP5, none of the standard asm/nops.h nops 
> are suitable.  Something like "0x66, 0x66, 0x66, 0x66, 0x90" would work
> everywhere, but its possible putting more than 3 prefixes on the 
> instruction will kick the decoder into a slow path, which may have a 
> noticable effect.

I guess the next step is to test if it is slow.

-- Steve

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