powerpc/perf: Enable BHRB access for EBB events
authorMichael Ellerman <mpe@ellerman.id.au>
Fri, 14 Mar 2014 05:00:34 +0000 (16:00 +1100)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Sun, 23 Mar 2014 22:48:27 +0000 (09:48 +1100)
commit76cb8a783a4b7403a6731ffdeec0831cd4b19936
tree03418d8204460f19b74ed88b453c3c5827dc32fa
parentba969237cfba17fcf0de8596b128f68259293137
powerpc/perf: Enable BHRB access for EBB events

The previous commit added constraint and register handling to allow
processes using EBB (Event Based Branches) to request access to the BHRB
(Branch History Rolling Buffer).

With that in place we can allow processes using EBB to access the BHRB.
This is achieved by setting BHRBA in MMCR0 when we enable EBB access. We
must also clear BHRBA when we are disabling.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/include/asm/reg.h
arch/powerpc/perf/core-book3s.c