Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 40 insertions, 0 deletions

diff --git a/Documentation/trace/events-msr.rst b/Documentation/trace/events-msr.rst
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+================
+MSR Trace Events
+================
+
+The x86 kernel supports tracing most MSR (Model Specific Register) accesses.
+To see the definition of the MSRs on Intel systems please see the SDM
+at http://www.intel.com/sdm (Volume 3)
+
+Available trace points:
+
+/sys/kernel/debug/tracing/events/msr/
+
+Trace MSR reads:
+
+read_msr
+
+  - msr: MSR number
+  - val: Value written
+  - failed: 1 if the access failed, otherwise 0
+
+
+Trace MSR writes:
+
+write_msr
+
+  - msr: MSR number
+  - val: Value written
+  - failed: 1 if the access failed, otherwise 0
+
+
+Trace RDPMC in kernel:
+
+rdpmc
+
+The trace data can be post processed with the postprocess/decode_msr.py script::
+
+  cat /sys/kernel/debug/tracing/trace | decode_msr.py /usr/src/linux/include/asm/msr-index.h
+
+to add symbolic MSR names.
+