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Date: Wed, 13 Oct 2010 16:58:00 +0200
From: Frederic Weisbecker <fweisbec@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Paul Mackerras <paulus@samba.org>,
        Stephane Eranian <eranian@google.com>,
        Cyrill Gorcunov <gorcunov@openvz.org>,
        Tom Zanussi <tzanussi@gmail.com>,
        Masami Hiramatsu <mhiramat@redhat.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Robert Richter <robert.richter@amd.com>,
        David Miller <davem@davemloft.net>
Subject: Re: [RFC PATCH 2/9] perf: Add ability to dump user regs
Message-ID: <20101013145757.GD5335@nowhere>
References: <1286946421-32202-1-git-send-regression-fweisbec@gmail.com> <1286946421-32202-3-git-send-regression-fweisbec@gmail.com> <1286954453.29097.58.camel@twins>
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On Wed, Oct 13, 2010 at 09:20:53AM +0200, Peter Zijlstra wrote:
> On Wed, 2010-10-13 at 07:06 +0200, Frederic Weisbecker wrote:
> > Add new PERF_SAMPLE_UREGS to perf sample type. This will dump the
> > user space context as it was before the user entered the kernel for
> > whatever reason.
> > 
> > This is going to be useful to bring Dwarf CFI based stack unwinding
> > on top of samples.
> 
> This doesn't address any of the issues that were raised previously.
> 
> There's a reason we don't have PERF_SAMPLE_*REGS like things.
> 
> See: http://lkml.org/lkml/2010/3/3/308


But the best would be to get it from sysfs I think.