linux-kernel - Re: [PATCH] ftrace/x86: Fix function graph tracer reset path

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Message-ID: <20160516191918.GC16265@pd.tnic>
Date:	Mon, 16 May 2016 21:19:18 +0200
From:	Borislav Petkov <bp@...e.de>
To:	Steven Rostedt <rostedt@...dmis.org>
Cc:	Namhyung Kim <namhyung@...nel.org>,
	Masami Hiramatsu <mhiramat@...nel.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...nel.org>, x86@...nel.org,
	"H.J. Lu" <hjl.tools@...il.com>
Subject: Re: [PATCH] ftrace/x86: Fix function graph tracer reset path

On Mon, May 16, 2016 at 03:13:57PM -0400, Steven Rostedt wrote:
> I actually thought about this first, but I thought it rather a hack
> (although one could argue all of function tracing is a hack ;-)

... I was about to say...

> But as the "weak" call was used to fix one location, why not use
> it here too. Being consistent, and also making sure all calls to
> ftrace_stub do the same.

Btw, arch_static_branch_jump() spells that 5-byte JMP too and not until
too long ago we had it in static_cpu_has()...

I guess after spending some time with the kernel, one can't really
differentiate hacks from proper design anymore. :-P

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--