powerpc/perf: Add lost exception workaround
authorMichael Ellerman <mpe@ellerman.id.au>
Fri, 14 Mar 2014 05:00:29 +0000 (16:00 +1100)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Sun, 23 Mar 2014 22:48:25 +0000 (09:48 +1100)
commitc2e37a2626a7471875f3a6452b99dfd3809972b9
tree60c994235d65095308288c8ee3543b1e027d2c92
parent68f2f0d431d9ea4fbd373cd31e828b0ceaefea30
powerpc/perf: Add lost exception workaround

Some power8 revisions have a hardware bug where we can lose a PMU
exception, this commit adds a workaround to detect the bad condition and
rectify the situation.

See the comment in the commit for a full description.

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
arch/powerpc/perf/power8-pmu.c