Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
tracing, doc: update mmiotrace documentation
Impact: update documentation
Update to reflect the current state of the tracing framework:
- "none" tracer has been replaced by "nop" tracer
- tracing_enabled must be toggled when changing buffer size
Signed-off-by: Pekka Paalanen <pq@iki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
authored by Pekka Paalanen and committed by Ingo Molnar fb91ee6c 7ee1768d
+4
-2
Documentation/tracers/mmiotrace.txt
+4
-2
Documentation/tracers/mmiotrace.txt
···
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$ cat /debug/tracing/trace_pipe > mydump.txt &
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Start X or whatever.
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$ echo "X is up" > /debug/tracing/trace_marker
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-
$ echo none > /debug/tracing/current_tracer
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+
$ echo nop > /debug/tracing/current_tracer
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Check for lost events.
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···
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do.
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Shut down mmiotrace (requires root privileges):
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-
$ echo none > /debug/tracing/current_tracer
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+
$ echo nop > /debug/tracing/current_tracer
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The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
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pressing ctrl+c.
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···
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$ cat /debug/tracing/trace_entries
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gives you a number. Approximately double this number and write it back, for
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instance:
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$ echo 0 > /debug/tracing/tracing_enabled
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$ echo 128000 > /debug/tracing/trace_entries
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+
$ echo 1 > /debug/tracing/tracing_enabled
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Then start again from the top.
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If you are doing a trace for a driver project, e.g. Nouveau, you should also