On 5 September 2013 14:45, Will Deacon will.deacon@arm.com wrote:
Hi Jean,
[adding Michael, since I know he was interested in this]
On Wed, Sep 04, 2013 at 07:04:14PM +0100, Jean Pihet wrote:
On ARM the debug info is not present in the .eh_frame sections but instead in .debug_frame. Use libunwind to load and parse the debug info.
How have you tested this? Regardless of whether or not I apply this patch, I get the same (broken/truncated) callchains for userspace in perf report.
Same here: I have applied these patches against 3.11 running on a Calxeda Highbank, and I never get more than a single entry for the userland part of the call stack.
E.g. the following stupid program (built with -O0 -g):
[...]
Gives me an incomplete callchain:
# Overhead Command Shared Object Symbol # ........ ........ ................. ............................... # 0.00% unwindme unwindme [.] bar | --- bar
I get exactly the same results, just bar and nothing below.