[PATCH 26/26] perf script: Add flamegraph.py script

Arnaldo Carvalho de Melo
2020-04-13T16:54:39Z

From: Andreas Gerstmayr <agerstmayr@redhat.com>

This script works in tandem with d3-flame-graph to generate flame graphs
from perf. It supports two output formats: JSON and HTML (the default).
The HTML format will look for a standalone d3-flame-graph template file
in /usr/share/d3-flame-graph/d3-flamegraph-base.html and fill in the
collected stacks.

Usage:

perf record -a -g -F 99 sleep 60
perf script report flamegraph

Combined:

perf script flamegraph -a -F 99 sleep 60

Committer testing:

Tested both with "PYTHON=python3" and with the default, that uses
python2-devel:

Complete set of instructions:

$ mkdir /tmp/build/perf
$ make PYTHON=python3 -C tools/perf O=/tmp/build/perf install-bin
$ export PATH=~/bin:$PATH
$ perf record -a -g -F 99 sleep 60
$ perf script report flamegraph

Now go and open the generated flamegraph.html file in a browser.

At first this required building with PYTHON=python3, but after I
reported this Andreas was kind enough to send a patch making it work
with both python and python3.

Signed-off-by: Andreas Gerstmayr <agerstmayr@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brendan Gregg <bgregg@netflix.com>
Cc: Martin Spier <mspier@netflix.com>
Link: http://lore.kernel.org/lkml/20200320151355.66302-1-agerstmayr@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
.../perf/scripts/python/bin/flamegraph-record | 2 +
.../perf/scripts/python/bin/flamegraph-report | 3 +
tools/perf/scripts/python/flamegraph.py | 124 ++++++++++++++++++
3 files changed, 129 insertions(+)
create mode 100755 tools/perf/scripts/python/bin/flamegraph-record
create mode 100755 tools/perf/scripts/python/bin/flamegraph-report
create mode 100755 tools/perf/scripts/python/flamegraph.py

diff --git a/tools/perf/scripts/python/bin/flamegraph-record b/tools/perf/scripts/python/bin/flamegraph-record
new file mode 100755
index 000000000000..725d66e71570
--- /dev/null
+++ b/tools/perf/scripts/python/bin/flamegraph-record
@@ -0,0 +1,2 @@
+#!/usr/bin/sh
+perf record -g "$@"
diff --git a/tools/perf/scripts/python/bin/flamegraph-report b/tools/perf/scripts/python/bin/flamegraph-report
new file mode 100755
index 000000000000..b1a79afd903b
--- /dev/null
+++ b/tools/perf/scripts/python/bin/flamegraph-report
@@ -0,0 +1,3 @@
+#!/usr/bin/sh
+# description: create flame graphs
+perf script -s "$PERF_EXEC_PATH"/scripts/python/flamegraph.py -- "$@"
diff --git a/tools/perf/scripts/python/flamegraph.py b/tools/perf/scripts/python/flamegraph.py
new file mode 100755
index 000000000000..61f3be9add6b
--- /dev/null
+++ b/tools/perf/scripts/python/flamegraph.py
@@ -0,0 +1,124 @@
+# flamegraph.py - create flame graphs from perf samples
+# SPDX-License-Identifier: GPL-2.0
+#
+# Usage:
+#
+# perf record -a -g -F 99 sleep 60
+# perf script report flamegraph
+#
+# Combined:
+#
+# perf script flamegraph -a -F 99 sleep 60
+#
+# Written by Andreas Gerstmayr <agerstmayr@redhat.com>
+# Flame Graphs invented by Brendan Gregg <bgregg@netflix.com>
+# Works in tandem with d3-flame-graph by Martin Spier <mspier@netflix.com>
+
+from __future__ import print_function
+import sys
+import os
+import argparse
+import json
+
+
+class Node:
+ def __init__(self, name, libtype=""):
+ self.name = name
+ self.libtype = libtype
+ self.value = 0
+ self.children = []
+
+ def toJSON(self):
+ return {
+ "n": self.name,
+ "l": self.libtype,
+ "v": self.value,
+ "c": self.children
+ }
+
+
+class FlameGraphCLI:
+ def __init__(self, args):
+ self.args = args
+ self.stack = Node("root")
+
+ if self.args.format == "html" and \
+ not os.path.isfile(self.args.template):
+ print("Flame Graph template {} does not exist. Please install "
+ "the js-d3-flame-graph (RPM) or libjs-d3-flame-graph (deb) "
+ "package, specify an existing flame graph template "
+ "(--template PATH) or another output format "
+ "(--format FORMAT).".format(self.args.template),
+ file=sys.stderr)
+ sys.exit(1)
+
+ def find_or_create_node(self, node, name, dso):
+ libtype = "kernel" if dso == "[kernel.kallsyms]" else ""
+ if name is None:
+ name = "[unknown]"
+
+ for child in node.children:
+ if child.name == name and child.libtype == libtype:
+ return child
+
+ child = Node(name, libtype)
+ node.children.append(child)
+ return child
+
+ def process_event(self, event):
+ node = self.find_or_create_node(self.stack, event["comm"], None)
+ if "callchain" in event:
+ for entry in reversed(event['callchain']):
+ node = self.find_or_create_node(
+ node, entry.get("sym", {}).get("name"), event.get("dso"))
+ else:
+ node = self.find_or_create_node(
+ node, entry.get("symbol"), event.get("dso"))
+ node.value += 1
+
+ def trace_end(self):
+ json_str = json.dumps(self.stack, default=lambda x: x.toJSON())
+
+ if self.args.format == "html":
+ try:
+ with open(self.args.template) as f:
+ output_str = f.read().replace("/** @flamegraph_json **/",
+ json_str)
+ except IOError as e:
+ print("Error reading template file: {}".format(e), file=sys.stderr)
+ sys.exit(1)
+ output_fn = self.args.output or "flamegraph.html"
+ else:
+ output_str = json_str
+ output_fn = self.args.output or "stacks.json"
+
+ if output_fn == "-":
+ sys.stdout.write(output_str)
+ else:
+ print("dumping data to {}".format(output_fn))
+ try:
+ with open(output_fn, "w") as out:
+ out.write(output_str)
+ except IOError as e:
+ print("Error writing output file: {}".format(e), file=sys.stderr)
+ sys.exit(1)
+
+
+if __name__ == "__main__":
+ parser = argparse.ArgumentParser(description="Create flame graphs.")
+ parser.add_argument("-f", "--format",
+ default="html", choices=["json", "html"],
+ help="output file format")
+ parser.add_argument("-o", "--output",
+ help="output file name")
+ parser.add_argument("--template",
+ default="/usr/share/d3-flame-graph/d3-flamegraph-base.html",
+ help="path to flamegraph HTML template")
+ parser.add_argument("-i", "--input",
+ help=argparse.SUPPRESS)
+
+ args = parser.parse_args()
+ cli = FlameGraphCLI(args)
+
+ process_event = cli.process_event
+ trace_end = cli.trace_end
--
2.21.1