In (93bfb76 clocksource: exynos_mct: register sched_clock callback) we
supported using the MCT as a scheduler clock. We properly marked
exynos4_read_sched_clock() as notrace. However, we then went and
called another function that _wasn't_ notrace. That means if you do:
cd /sys/kernel/debug/tracing/
echo function_graph > current_tracer
You'll get a crash.
Fix this (but still let other readers of the MCT be trace-enabled) by
adding an extra function. It's important to keep other users of MCT
traceable because the MCT is actually quite slow to access and we want
exynos4_frc_read() to show up in ftrace profiles if it's the
bottleneck.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
89e6a13b88