On Tue, 2013-10-15 at 14:53 -0500, Benjamin Herrenschmidt wrote:

On Tue, 2013-10-15 at 14:44 -0400, Martin Hicks wrote:

quoted

On Tue, Oct 15, 2013 at 11:30 AM, Benjamin Herrenschmidt
[off-list ref] wrote:

quoted

On Tue, 2013-10-15 at 09:59 -0400, Martin Hicks wrote:

quoted

I've tracked the start of the strange instruction pointers in 'perf
report' to a commit by Anton:

commit 75382aa72f06823db7312ad069c3bae2eb3f8548
Author: Anton Blanchard [off-list ref]
Date:   Tue Jun 26 01:01:36 2012 +0000

    powerpc/perf: Move code to select SIAR or pt_regs into perf_read_regs

I don't know enough about PPC to know what's going on, but reverting
the changes to perf_instruction_pointer() gets me reasonable 'perf
report' output with 3.11.

This is an e300 core right ? (603...). Do that have an SIAR at all
(Scott ?)

Yes, e300c3.

Ok so I have a hard time figuring out how that patch can make a
difference since for all I can see, there is no perf backend upstream
for e300 at all :-(

I must certainly be missing something ... Scott, can you have a look ?

e300c3 has a core-fsl-emb style performance monitor (though Linux
doesn't support it yet).  If a bug was bisected to a change in
core-book3s.c, then it's probably a coincidence due to moving code
around.

-Scott