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Diffstat (limited to 'tools/perf/Documentation/perf-ftrace.txt')
| -rw-r--r-- | tools/perf/Documentation/perf-ftrace.txt | 77 |
1 files changed, 76 insertions, 1 deletions
diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt index d780b93fcf87..3f3808e513fe 100644 --- a/tools/perf/Documentation/perf-ftrace.txt +++ b/tools/perf/Documentation/perf-ftrace.txt @@ -9,7 +9,7 @@ perf-ftrace - simple wrapper for kernel's ftrace functionality SYNOPSIS -------- [verse] -'perf ftrace' {trace|latency} <command> +'perf ftrace' {trace|latency|profile} <command> DESCRIPTION ----------- @@ -23,6 +23,9 @@ kernel's ftrace infrastructure. 'perf ftrace latency' calculates execution latency of a given function (optionally with BPF) and display it as a histogram. + 'perf ftrace profile' show a execution profile for each function including + total, average, max time and the number of calls. + The following options apply to perf ftrace. COMMON OPTIONS @@ -120,11 +123,16 @@ OPTIONS for 'perf ftrace trace' --graph-opts:: List of options allowed to set: + - args - Show function arguments. + - retval - Show function return value. + - retval-hex - Show function return value in hexadecimal format. + - retaddr - Show function return address. - 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. + - tail - Print function name at the end. OPTIONS for 'perf ftrace latency' @@ -135,6 +143,12 @@ OPTIONS for 'perf ftrace latency' Set the function name to get the histogram. Unlike perf ftrace trace, it only allows single function to calculate the histogram. +-e:: +--events=:: + Set the pair of events to get the histogram. The histogram is calculated + by the time difference between the two events from the same thread. This + requires -b/--use-bpf option. + -b:: --use-bpf:: Use BPF to measure function latency instead of using the ftrace (it @@ -144,6 +158,67 @@ OPTIONS for 'perf ftrace latency' --use-nsec:: Use nano-second instead of micro-second as a base unit of the histogram. +--bucket-range=:: + Bucket range in ms or ns (according to -n/--use-nsec), default is log2() mode. + +--min-latency=:: + Minimum latency for the start of the first bucket, in ms or ns (according to + -n/--use-nsec). + +--max-latency=:: + Maximum latency for the start of the last bucket, in ms or ns (according to + -n/--use-nsec). The setting is ignored if the value results in more than + 22 buckets. + +OPTIONS for 'perf ftrace profile' +--------------------------------- + +-T:: +--trace-funcs=:: + 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=:: + 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. + +-G:: +--graph-funcs=:: + 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=:: + 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. + +-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. + +-s:: +--sort=:: + Sort the result by the given field. Available values are: + total, avg, max, count, name. Default is 'total'. + +--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. + - thresh=<n> - Setup trace duration threshold in microseconds. + - depth=<n> - Set max depth for function graph tracer to follow. + SEE ALSO -------- |