From: Michael Neuling <mikey@neuling.org>
Date: Mon, 13 May 2013 18:44:58 +0000 (+0000)
Subject: powerpc/perf: Fix setting of "to" addresses for BHRB
X-Git-Tag: v3.10-rc2~31^2~1
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=691231846cebfe1fbbcf898c8af17a569dbb5463;p=pandora-kernel.git

powerpc/perf: Fix setting of "to" addresses for BHRB

Currently we only set the "to" address in the branch stack when the CPU
explicitly gives us a value.  Unfortunately it only does this for XL form
branches (eg blr, bctr, bctar) and not I and B form branches (eg b, bc).

Fortunately if we read the instruction from memory we can extract the offset of
a branch and calculate the target address.

This adds a function power_pmu_bhrb_to() to calculate the target/to address of
the corresponding I and B form branches.  It handles branches in both user and
kernel spaces.  It also plumbs this into the perf brhb reading code.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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