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Subject: Re: [PATCH v2] ftrace: On PowerPC we don't need frame pointers for
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From: Steven Rostedt <srostedt@redhat.com>
To: avorontsov@ru.mvista.com
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Date: Tue, 03 Feb 2009 11:32:18 -0500
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Cc: Ingo Molnar <mingo@elte.hu>, Paul Mackerras <paulus@samba.org>,
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On Tue, 2009-02-03 at 19:19 +0300, Anton Vorontsov wrote:
> On Tue, Feb 03, 2009 at 05:06:45PM +0100, Ingo Molnar wrote:

> [1] Btw, why exactly do we need the -fno-omit-frame-pointer for
> "FUNCTION_TRCER" tracer? Why just -pg isn't sufficient?..
> 

The problem is this that is in the toplevel Makefile:


ifdef CONFIG_FRAME_POINTER
KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
else
KBUILD_CFLAGS	+= -fomit-frame-pointer
endif


-pg is incompatible with -fomit-frame-pointer

-- Steve