This adds an option '--graph-thresh' to setup trace duration threshold for funcgraph tracer.
$ sudo ./perf ftrace -G --graph-thresh 100 3) ! 184.060 us | } /* schedule */ 3) ! 185.600 us | } /* exit_to_usermode_loop */ 2) ! 225.989 us | } /* schedule_idle */ 2) # 4140.051 us | } /* do_idle */ Signed-off-by: Changbin Du <[email protected]> --- tools/perf/Documentation/perf-ftrace.txt | 3 +++ tools/perf/builtin-ftrace.c | 25 ++++++++++++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt index cc770fc0a1e8..64843d0cdc45 100644 --- a/tools/perf/Documentation/perf-ftrace.txt +++ b/tools/perf/Documentation/perf-ftrace.txt @@ -116,6 +116,9 @@ OPTIONS --graph-verbose:: Show process names, PIDs, timestamps for function_graph tracer. +--graph-thresh:: + Setup trace duration threshold for funcgraph tracer. + SEE ALSO -------- linkperf:perf-record[1], linkperf:perf-trace[1] diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c index e037fe7abd47..0f8716ea0da4 100644 --- a/tools/perf/builtin-ftrace.c +++ b/tools/perf/builtin-ftrace.c @@ -46,6 +46,7 @@ struct perf_ftrace { bool graph_nosleep_time; bool graph_noirqs; bool graph_verbose; + unsigned graph_thresh; }; struct filter_entry { @@ -229,6 +230,9 @@ static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused) if (write_tracing_file("max_graph_depth", "0") < 0) return -1; + if (write_tracing_file("tracing_thresh", "0") < 0) + return -1; + reset_tracing_filters(); reset_tracing_options(ftrace); return 0; @@ -440,6 +444,20 @@ static int set_tracing_funcgraph_verbose(struct perf_ftrace *ftrace) return 0; } +static int set_tracing_thresh(struct perf_ftrace *ftrace) +{ + int ret; + + if (ftrace->graph_thresh == 0) + return 0; + + ret = write_tracing_file_int("tracing_thresh", ftrace->graph_thresh); + if (ret < 0) + return ret; + + return 0; +} + static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) { char *trace_file; @@ -539,6 +557,11 @@ static int __cmd_ftrace(struct perf_ftrace *ftrace, int argc, const char **argv) goto out_reset; } + if (set_tracing_thresh(ftrace) < 0) { + pr_err("failed to set tracing thresh\n"); + goto out_reset; + } + if (write_tracing_file("current_tracer", ftrace->tracer) < 0) { pr_err("failed to set current_tracer to %s\n", ftrace->tracer); goto out_reset; @@ -726,6 +749,8 @@ int cmd_ftrace(int argc, const char **argv) "ignore functions that happen inside interrupt for function_graph tracer"), OPT_BOOLEAN(0, "graph-verbose", &ftrace.graph_verbose, "show process names, PIDs, timestamps for function_graph tracer"), + OPT_UINTEGER(0, "graph-thresh", &ftrace.graph_thresh, + "only show functions of which the duration is greater than <n>µs"), OPT_END() }; -- 2.25.1
