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Date: Mon, 7 May 2018 11:40:01 -0700
From: Andi Kleen <ak@linux.intel.com>
To: Josh Hunt <johunt@akamai.com>
Cc: mingo@redhat.com, acme@kernel.org, peterz@infradead.org,
        alexander.shishkin@linux.intel.com, jolsa@redhat.com,
        namhyung@kernel.org, wangnan0@huawei.com,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
        eranian@google.com
Subject: Re: [PATCH v2] perf tools: allow map files to specify DSO
Message-ID: <20180507184001.GE4050@tassilo.jf.intel.com>
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On Mon, May 07, 2018 at 02:24:16PM -0400, Josh Hunt wrote:
> Add the ability to specify a DSO in the /tmp/perf-<PID>.map file.
> The DSO should be the first line in the file and readable by the
> running user. If a valid DSO is found all other contents of the
> file will be ignored. This allows things like callchain unwinding
> with DWARF to work.

FWIW it's ok, but also obsolete with Kirill's large-pages-in-tmpfs
work in newer kernels. With that you can just copy the executable into
a 2MB tmpfs and disable the manual huge page copying and everything
should work as usually.

So essentially it's only a hack for old kernels and old binaries.

But doesn't hurt I guess.

-Andi