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diff --git a/Documentation/trace/power.txt b/Documentation/trace/power.txt
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+The power tracer collects detailed information about C-state and P-state
+transitions, instead of just looking at the high-level "average"
+information.
+
+There is a helper script found in scrips/tracing/power.pl in the kernel
+sources which can be used to parse this information and create a
+Scalable Vector Graphics (SVG) picture from the trace data.
+
+To use this tracer:
+
+        echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+        echo power > /sys/kernel/debug/tracing/current_tracer
+        echo 1 > /sys/kernel/debug/tracing/tracing_enabled
+        sleep 1
+        echo 0 > /sys/kernel/debug/tracing/tracing_enabled
+        cat /sys/kernel/debug/tracing/trace | \
+                perl scripts/tracing/power.pl > out.sv