perf trace/scripting: Update Documentation

SYNOPSIS

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[verse]

'perf trace' [-i <file> | --input=file] symbol_name

'perf trace' {record <script> | report <script> [args] }

DESCRIPTION

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This command reads the input file and displays the trace recorded.

There are several variants of perf trace:

  'perf trace' to see a detailed trace of the workload that was

  recorded.

  'perf trace record <script>' to record the events required for 'perf

  trace report'.  <script> is the name displayed in the output of

  'perf trace --list' i.e. the actual script name minus any language

  extension.

  'perf trace report <script>' to run and display the results of

  <script>.  <script> is the name displayed in the output of 'perf

  trace --list' i.e. the actual script name minus any language

  extension.  The perf.data output from a previous run of 'perf trace

  record <script>' is used and should be present for this command to

  succeed.

OPTIONS

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-D::

--dump-raw-trace=::

        Display verbose dump of the trace data.

-L::

--Latency=::

        Show latency attributes (irqs/preemption disabled, etc).

-l::

--list=::

        Display a list of available trace scripts.

-s::

--script=::

        Process trace data with the given script ([lang]:script[.ext]).