powerpc/oprofile: Handle events that raise an exception without overflowing
commit148f054048b33a4e506710837eecce266d7523b3
authorEric B Munson <emunson@mgebm.net>
Mon, 23 May 2011 04:22:40 +0000 (23 04:22 +0000)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 3 Jun 2011 01:33:40 +0000 (3 10:33 +0900)
tree59865bd52bedc71001c6552a23c4491e31d35c92
parentf003fed4410b5da934d4663db9dfb8693dd8dca8
powerpc/oprofile: Handle events that raise an exception without overflowing

commit ad5d5292f16c6c1d7d3e257c4c7407594286b97e upstream.

Commit 0837e3242c73566fc1c0196b4ec61779c25ffc93 fixes a situation on POWER7
where events can roll back if a specualtive event doesn't actually complete.
This can raise a performance monitor exception.  We need to catch this to ensure
that we reset the PMC.  In all cases the PMC will be less than 256 cycles from
overflow.

This patch lifts Anton's fix for the problem in perf and applies it to oprofile
as well.

Signed-off-by: Eric B Munson <emunson@mgebm.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
arch/powerpc/oprofile/op_model_power4.c