[PATCH v3] perf script flamegraph: Avoid d3-flame-graph package dependency

From: Ian Rogers
Date: Thu Jan 19 2023 - 13:31:41 EST


Currently flame graph generation requires a d3-flame-graph template to
be installed. Unfortunately this is hard to come by for things like
Debian [1]. If the template isn't installed then ask if it should be
downloaded from jsdelivr CDN. The downloaded HTML file is validated
against an md5sum. If the download fails, generate a minimal flame
graph with the javascript coming from links to jsdelivr CDN.

v3. Adds a warning message and quits before download in live mode.
v2. Change the warning to a prompt about downloading and add the
--allow-download command line flag. Add an md5sum check for the
downloaded HTML.

[1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=996839

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/scripts/python/flamegraph.py | 107 +++++++++++++++++++-----
1 file changed, 85 insertions(+), 22 deletions(-)

diff --git a/tools/perf/scripts/python/flamegraph.py b/tools/perf/scripts/python/flamegraph.py
index b6af1dd5f816..cf7ce8229a6c 100755
--- a/tools/perf/scripts/python/flamegraph.py
+++ b/tools/perf/scripts/python/flamegraph.py
@@ -19,12 +19,34 @@
# pylint: disable=missing-function-docstring

from __future__ import print_function
-import sys
-import os
-import io
import argparse
+import hashlib
+import io
import json
+import os
import subprocess
+import sys
+import urllib.request
+
+minimal_html = """<head>
+ <link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/npm/d3-flame-graph@4.1.3/dist/d3-flamegraph.css";>
+</head>
+<body>
+ <div id="chart"></div>
+ <script type="text/javascript" src="https://d3js.org/d3.v7.js";></script>
+ <script type="text/javascript" src="https://cdn.jsdelivr.net/npm/d3-flame-graph@4.1.3/dist/d3-flamegraph.min.js";></script>
+ <script type="text/javascript">
+ const stacks = [/** @flamegraph_json **/];
+ // Note, options is unused.
+ const options = [/** @options_json **/];
+
+ var chart = flamegraph();
+ d3.select("#chart")
+ .datum(stacks[0])
+ .call(chart);
+ </script>
+</body>
+"""

# pylint: disable=too-few-public-methods
class Node:
@@ -50,16 +72,6 @@ class FlameGraphCLI:
self.args = args
self.stack = Node("all", "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)
-
@staticmethod
def get_libtype_from_dso(dso):
"""
@@ -128,16 +140,63 @@ class FlameGraphCLI:
}
options_json = json.dumps(options)

+ template_md5sum = None
+ if self.args.format == "html":
+ if os.path.isfile(self.args.template):
+ template = f"file://{self.args.template}"
+ else:
+ if not self.args.allow_download:
+ print(f"""Warning: Flame Graph template '{self.args.template}'
+does not exist. To avoid this please install a package such as the
+js-d3-flame-graph or libjs-d3-flame-graph, specify an existing flame
+graph template (--template PATH) or use another output format (--format
+FORMAT).""",
+ file=sys.stderr)
+ if self.args.input == "-":
+ print("""Not attempting to download Flame Graph template as script command line
+input is disabled due to using live mode. If you want to download the
+template retry without live mode. For example, use 'perf record -a -g
+-F 99 sleep 60' and 'perf script report flamegraph'. Alternatively,
+download the template from:
+https://cdn.jsdelivr.net/npm/d3-flame-graph@4.1.3/dist/templates/d3-flamegraph-base.html
+and place it at:
+/usr/share/d3-flame-graph/d3-flamegraph-base.html""",
+ file=sys.stderr)
+ quit()
+ s = None
+ while s != "y" and s != "n":
+ s = input("Do you wish to download a template from cdn.jsdelivr.net? (this warning can be suppressed with --allow-download) [yn] ").lower()
+ if s == "n":
+ quit()
+ template = "https://cdn.jsdelivr.net/npm/d3-flame-graph@4.1.3/dist/templates/d3-flamegraph-base.html";
+ template_md5sum = "143e0d06ba69b8370b9848dcd6ae3f36"
+
try:
- with io.open(self.args.template, encoding="utf-8") as template:
- output_str = (
- template.read()
- .replace("/** @options_json **/", options_json)
- .replace("/** @flamegraph_json **/", stacks_json)
- )
- except IOError as err:
- print("Error reading template file: {}".format(err), file=sys.stderr)
- sys.exit(1)
+ with urllib.request.urlopen(template) as template:
+ output_str = "".join([
+ l.decode("utf-8") for l in template.readlines()
+ ])
+ except Exception as err:
+ print(f"Error reading template {template}: {err}\n"
+ "a minimal flame graph will be generated", file=sys.stderr)
+ output_str = minimal_html
+ template_md5sum = None
+
+ if template_md5sum:
+ download_md5sum = hashlib.md5(output_str.encode("utf-8")).hexdigest()
+ if download_md5sum != template_md5sum:
+ s = None
+ while s != "y" and s != "n":
+ s = input(f"""Unexpected template md5sum.
+{download_md5sum} != {template_md5sum}, for:
+{output_str}
+continue?[yn] """).lower()
+ if s == "n":
+ quit()
+
+ output_str = output_str.replace("/** @options_json **/", options_json)
+ output_str = output_str.replace("/** @flamegraph_json **/", stacks_json)
+
output_fn = self.args.output or "flamegraph.html"
else:
output_str = stacks_json
@@ -172,6 +231,10 @@ if __name__ == "__main__":
choices=["blue-green", "orange"])
parser.add_argument("-i", "--input",
help=argparse.SUPPRESS)
+ parser.add_argument("--allow-download",
+ default=False,
+ action="store_true",
+ help="allow unprompted downloading of HTML template")

cli_args = parser.parse_args()
cli = FlameGraphCLI(cli_args)
--
2.39.0.314.g84b9a713c41-goog