# 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 # Flame Graphs invented by Brendan Gregg # Works in tandem with d3-flame-graph by Martin Spier # # pylint: disable=missing-module-docstring # pylint: disable=missing-class-docstring # pylint: disable=missing-function-docstring from __future__ import print_function import argparse import hashlib import io import json import os import subprocess import sys import urllib.request minimal_html = """

""" # pylint: disable=too-few-public-methods class Node: def __init__(self, name, libtype): self.name = name # "root" | "kernel" | "" # "" indicates user space self.libtype = libtype self.value = 0 self.children = [] def to_json(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("all", "root") @staticmethod def get_libtype_from_dso(dso): """ when kernel-debuginfo is installed, dso points to /usr/lib/debug/lib/modules/*/vmlinux """ if dso and (dso == "[kernel.kallsyms]" or dso.endswith("/vmlinux")): return "kernel" return "" @staticmethod def find_or_create_node(node, name, libtype): for child in node.children: if child.name == name: return child child = Node(name, libtype) node.children.append(child) return child def process_event(self, event): pid = event.get("sample", {}).get("pid", 0) # event["dso"] sometimes contains /usr/lib/debug/lib/modules/*/vmlinux # for user-space processes; let's use pid for kernel or user-space distinction if pid == 0: comm = event["comm"] libtype = "kernel" else: comm = "{} ({})".format(event["comm"], pid) libtype = "" node = self.find_or_create_node(self.stack, comm, libtype) if "callchain" in event: for entry in reversed(event["callchain"]): name = entry.get("sym", {}).get("name", "[unknown]") libtype = self.get_libtype_from_dso(entry.get("dso")) node = self.find_or_create_node(node, name, libtype) else: name = event.get("symbol", "[unknown]") libtype = self.get_libtype_from_dso(event.get("dso")) node = self.find_or_create_node(node, name, libtype) node.value += 1 def get_report_header(self): if self.args.input == "-": # when this script is invoked with "perf script flamegraph", # no perf.data is created and we cannot read the header of it return "" try: output = subprocess.check_output(["perf", "report", "--header-only"]) return output.decode("utf-8") except Exception as err: # pylint: disable=broad-except print("Error reading report header: {}".format(err), file=sys.stderr) return "" def trace_end(self): stacks_json = json.dumps(self.stack, default=lambda x: x.to_json()) if self.args.format == "html": report_header = self.get_report_header() options = { "colorscheme": self.args.colorscheme, "context": report_header } 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 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 output_fn = self.args.output or "stacks.json" if output_fn == "-": with io.open(sys.stdout.fileno(), "w", encoding="utf-8", closefd=False) as out: out.write(output_str) else: print("dumping data to {}".format(output_fn)) try: with io.open(output_fn, "w", encoding="utf-8") as out: out.write(output_str) except IOError as err: print("Error writing output file: {}".format(err), 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 flame graph HTML template") parser.add_argument("--colorscheme", default="blue-green", help="flame graph color scheme", 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) process_event = cli.process_event trace_end = cli.trace_end