Commit 00c85d5f authored by Changbin Du's avatar Changbin Du Committed by Arnaldo Carvalho de Melo
Browse files

perf ftrace: Add support for trace option tracing_thresh 



This adds an option '--graph-opts thresh' to setup trace duration
threshold for funcgraph tracer.

  $ sudo ./perf ftrace -G '*' --graph-opts 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: default avatarChangbin Du <changbin.du@gmail.com>
Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lore.kernel.org/lkml/20200808023141.14227-14-changbin.du@gmail.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 59486fb0

tools/perf/Documentation/perf-ftrace.txt

+1 −0
Original line number Diff line number Diff line
@@ -107,6 +107,7 @@ OPTIONS 
	  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.



SEE ALSO

--------

tools/perf/builtin-ftrace.c

+25 −1
Original line number Diff line number Diff line
@@ -48,6 +48,7 @@ struct perf_ftrace { 
	int			graph_nosleep_time;

	int			graph_noirqs;

	int			graph_verbose;

	int			graph_thresh;

};



struct filter_entry {
@@ -234,6 +235,9 @@ 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;
@@ -446,6 +450,20 @@ 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;
@@ -545,6 +563,11 @@ 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;
@@ -727,6 +750,7 @@ static int parse_graph_tracer_opts(const struct option *opt, 
		{ .name = "nosleep-time",	.value_ptr = &ftrace->graph_nosleep_time },

		{ .name = "noirqs",		.value_ptr = &ftrace->graph_noirqs },

		{ .name = "verbose",		.value_ptr = &ftrace->graph_verbose },

		{ .name = "thresh",		.value_ptr = &ftrace->graph_thresh },

		{ .name = NULL, }

	};
@@ -798,7 +822,7 @@ int cmd_ftrace(int argc, const char **argv) 
	OPT_INTEGER('D', "graph-depth", &ftrace.graph_depth,

		    "Max depth for function graph tracer"),

	OPT_CALLBACK(0, "graph-opts", &ftrace, "options",

		     "graph tracer options, available options: nosleep-time,noirqs,verbose",

		     "graph tracer options, available options: nosleep-time,noirqs,verbose,thresh=<n>",

		     parse_graph_tracer_opts),

	OPT_CALLBACK('m', "buffer-size", &ftrace.percpu_buffer_size, "size",

		     "size of per cpu buffer", parse_buffer_size),

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