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+perf-ftrace(1)
+==============
+
+NAME
+----
+perf-ftrace - simple wrapper for kernel's ftrace functionality
+
+
+SYNOPSIS
+--------
+[verse]
+'perf ftrace' {trace|latency} <command>
+
+DESCRIPTION
+-----------
+The 'perf ftrace' command provides a collection of subcommands which use
+kernel's ftrace infrastructure.
+
+  'perf ftrace trace' is a simple wrapper of the ftrace.  It only supports
+  single thread tracing currently and just reads trace_pipe in text and then
+  write it to stdout.
+
+  'perf ftrace latency' calculates execution latency of a given function
+  (optionally with BPF) and display it as a histogram.
+
+The following options apply to perf ftrace.
+
+COMMON OPTIONS
+--------------
+
+-p::
+--pid=::
+	Trace on existing process id (comma separated list).
+
+--tid=::
+	Trace on existing thread id (comma separated list).
+
+-a::
+--all-cpus::
+	Force system-wide collection.  Scripts run without a <command>
+	normally use -a by default, while scripts run with a <command>
+	normally don't - this option allows the latter to be run in
+	system-wide mode.
+
+-C::
+--cpu=::
+	Only trace for the list of CPUs provided.  Multiple CPUs can
+	be provided as a comma separated list with no space like: 0,1.
+	Ranges of CPUs are specified with -: 0-2.
+	Default is to trace on all online CPUs.
+
+-v::
+--verbose::
+        Increase the verbosity level.
+
+
+OPTIONS for 'perf ftrace trace'
+-------------------------------
+
+-t::
+--tracer=::
+	Tracer to use when neither -G nor -F option is not
+	specified: function_graph or function.
+
+-F::
+--funcs::
+        List available functions to trace. It accepts a pattern to
+        only list interested functions.
+
+-D::
+--delay::
+	Time (ms) to wait before starting tracing after program start.
+
+-m::
+--buffer-size::
+	Set the size of per-cpu tracing buffer, <size> is expected to
+	be a number with appended unit character - B/K/M/G.
+
+--inherit::
+	Trace children processes spawned by our target.
+
+-T::
+--trace-funcs=::
+	Select function tracer and set function filter on the given
+	function (or a glob pattern). Multiple functions can be given
+	by using this option more than once. The function argument also
+	can be a glob pattern. It will be passed to 'set_ftrace_filter'
+	in tracefs.
+
+-N::
+--notrace-funcs=::
+	Select function tracer and do not trace functions given by the
+	argument.  Like -T option, this can be used more than once to
+	specify multiple functions (or glob patterns).  It will be
+	passed to 'set_ftrace_notrace' in tracefs.
+
+--func-opts::
+	List of options allowed to set:
+	  call-graph - Display kernel stack trace for function tracer.
+	  irq-info   - Display irq context info for function tracer.
+
+-G::
+--graph-funcs=::
+	Select function_graph tracer and set graph filter on the given
+	function (or a glob pattern). This is useful to trace for
+	functions executed from the given function. This can be used more
+	than once to specify multiple functions. It will be passed to
+	'set_graph_function' in tracefs.
+
+-g::
+--nograph-funcs=::
+	Select function_graph tracer and set graph notrace filter on the
+	given function (or a glob pattern). Like -G option, this is useful
+	for the function_graph tracer only and disables tracing for function
+	executed from the given function. This can be used more than once to
+	specify multiple functions. It will be passed to 'set_graph_notrace'
+	in tracefs.
+
+--graph-opts::
+	List of options allowed to set:
+	  nosleep-time - Measure on-CPU time only for function_graph tracer.
+	  noirqs       - Ignore functions that happen inside interrupt.
+	  verbose      - Show process names, PIDs, timestamps, etc.
+	  thresh=<n>   - Setup trace duration threshold in microseconds.
+	  depth=<n>    - Set max depth for function graph tracer to follow.
+
+
+OPTIONS for 'perf ftrace latency'
+---------------------------------
+
+-T::
+--trace-funcs=::
+	Set the function name to get the histogram.  Unlike perf ftrace trace,
+	it only allows single function to calculate the histogram.
+
+-b::
+--use-bpf::
+	Use BPF to measure function latency instead of using the ftrace (it
+	uses function_graph tracer internally).
+
+-n::
+--use-nsec::
+	Use nano-second instead of micro-second as a base unit of the histogram.
+
+
+SEE ALSO
+--------
+linkperf:perf-record[1], linkperf:perf-trace[1]