On Tue, Jun 18, 2013 at 02:13:19PM +0100, Will Deacon wrote:

On Fri, Jun 14, 2013 at 12:21:11AM +0100, Jed Davis wrote:

quoted

With this change, we no longer lose the innermost entry in the user-mode
part of the call chain.  See also the x86 port, which includes the ip.

It's possible to partially work around this problem by post-processing
the data to use the PERF_SAMPLE_IP value, but this works only if the CPU
wasn't in the kernel when the sample was taken.

Thanks. I guess we need something similar for arm64 too. Could you cook a
similar patch please?

Done (and tested, on the ARM V8 Foundation Model).

It looked as if the powerpc and sparc ports might have similar issues,
but I haven't checked on them yet.

--Jed