6 perf-ftrace - simple wrapper for kernel's ftrace functionality
12 'perf ftrace' <command>
16 The 'perf ftrace' command is a simple wrapper of kernel's ftrace
17 functionality. It only supports single thread tracing currently and
18 just reads trace_pipe in text and then write it to stdout.
20 The following options apply to perf ftrace.
27 Tracer to use when neither -G nor -F option is not
28 specified: function_graph or function.
36 List available functions to trace. It accepts a pattern to
37 only list interested functions.
41 Trace on existing process id (comma separated list).
44 Trace on existing thread id (comma separated list).
48 Time (ms) to wait before starting tracing after program start.
52 Force system-wide collection. Scripts run without a <command>
53 normally use -a by default, while scripts run with a <command>
54 normally don't - this option allows the latter to be run in
59 Only trace for the list of CPUs provided. Multiple CPUs can
60 be provided as a comma separated list with no space like: 0,1.
61 Ranges of CPUs are specified with -: 0-2.
62 Default is to trace on all online CPUs.
66 Set the size of per-cpu tracing buffer, <size> is expected to
67 be a number with appended unit character - B/K/M/G.
70 Trace children processes spawned by our target.
74 Select function tracer and set function filter on the given
75 function (or a glob pattern). Multiple functions can be given
76 by using this option more than once. The function argument also
77 can be a glob pattern. It will be passed to 'set_ftrace_filter'
82 Select function tracer and do not trace functions given by the
83 argument. Like -T option, this can be used more than once to
84 specify multiple functions (or glob patterns). It will be
85 passed to 'set_ftrace_notrace' in tracefs.
88 List of options allowed to set:
89 call-graph - Display kernel stack trace for function tracer.
90 irq-info - Display irq context info for function tracer.
94 Select function_graph tracer and set graph filter on the given
95 function (or a glob pattern). This is useful to trace for
96 functions executed from the given function. This can be used more
97 than once to specify multiple functions. It will be passed to
98 'set_graph_function' in tracefs.
102 Select function_graph tracer and set graph notrace filter on the
103 given function (or a glob pattern). Like -G option, this is useful
104 for the function_graph tracer only and disables tracing for function
105 executed from the given function. This can be used more than once to
106 specify multiple functions. It will be passed to 'set_graph_notrace'
110 List of options allowed to set:
111 nosleep-time - Measure on-CPU time only for function_graph tracer.
112 noirqs - Ignore functions that happen inside interrupt.
113 verbose - Show process names, PIDs, timestamps, etc.
114 thresh=<n> - Setup trace duration threshold in microseconds.
115 depth=<n> - Set max depth for function graph tracer to follow.
119 linkperf:perf-record[1], linkperf:perf-trace[1]