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Date: Mon, 16 May 2011 18:49:39 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <andi@firstfloor.org>, Andy Lutomirski <luto@MIT.EDU>,
        x86@kernel.org, linux-kernel@vger.kernel.org,
        Ingo Molnar <mingo@elte.hu>,
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        Eric Dumazet <eric.dumazet@gmail.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Borislav Petkov <bp@amd64.org>
Subject: Re: [PATCH v4 0/6] Micro-optimize vclock_gettime
Message-ID: <20110516164939.GD25898@one.firstfloor.org>
References: <cover.1305560561.git.luto@mit.edu> <20110516160943.GC25898@one.firstfloor.org> <alpine.LFD.2.02.1105161817120.3078@ionos>
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> And unless you or someone else changes the primitive state of the
> kernel, framepointers are going to stay simply because removing them
> breaks profiling backtraces when the hit is inside vread().

This doesn't work anyways because the glibc stub code calling vgettimeofday
normally doesn't set up a frame pointer frame.

The only way to unwind there is dwarf2.

-Andi