1# flamegraph.py - create flame graphs from perf samples 2# SPDX-License-Identifier: GPL-2.0 3# 4# Usage: 5# 6# perf record -a -g -F 99 sleep 60 7# perf script report flamegraph 8# 9# Combined: 10# 11# perf script flamegraph -a -F 99 sleep 60 12# 13# Written by Andreas Gerstmayr <agerstmayr@redhat.com> 14# Flame Graphs invented by Brendan Gregg <bgregg@netflix.com> 15# Works in tandem with d3-flame-graph by Martin Spier <mspier@netflix.com> 16# 17# pylint: disable=missing-module-docstring 18# pylint: disable=missing-class-docstring 19# pylint: disable=missing-function-docstring 20 21from __future__ import print_function 22import sys 23import os 24import io 25import argparse 26import json 27import subprocess 28 29# pylint: disable=too-few-public-methods 30class Node: 31 def __init__(self, name, libtype): 32 self.name = name 33 # "root" | "kernel" | "" 34 # "" indicates user space 35 self.libtype = libtype 36 self.value = 0 37 self.children = [] 38 39 def to_json(self): 40 return { 41 "n": self.name, 42 "l": self.libtype, 43 "v": self.value, 44 "c": self.children 45 } 46 47 48class FlameGraphCLI: 49 def __init__(self, args): 50 self.args = args 51 self.stack = Node("all", "root") 52 53 if self.args.format == "html" and \ 54 not os.path.isfile(self.args.template): 55 print("Flame Graph template {} does not exist. Please install " 56 "the js-d3-flame-graph (RPM) or libjs-d3-flame-graph (deb) " 57 "package, specify an existing flame graph template " 58 "(--template PATH) or another output format " 59 "(--format FORMAT).".format(self.args.template), 60 file=sys.stderr) 61 sys.exit(1) 62 63 @staticmethod 64 def get_libtype_from_dso(dso): 65 """ 66 when kernel-debuginfo is installed, 67 dso points to /usr/lib/debug/lib/modules/*/vmlinux 68 """ 69 if dso and (dso == "[kernel.kallsyms]" or dso.endswith("/vmlinux")): 70 return "kernel" 71 72 return "" 73 74 @staticmethod 75 def find_or_create_node(node, name, libtype): 76 for child in node.children: 77 if child.name == name: 78 return child 79 80 child = Node(name, libtype) 81 node.children.append(child) 82 return child 83 84 def process_event(self, event): 85 pid = event.get("sample", {}).get("pid", 0) 86 # event["dso"] sometimes contains /usr/lib/debug/lib/modules/*/vmlinux 87 # for user-space processes; let's use pid for kernel or user-space distinction 88 if pid == 0: 89 comm = event["comm"] 90 libtype = "kernel" 91 else: 92 comm = "{} ({})".format(event["comm"], pid) 93 libtype = "" 94 node = self.find_or_create_node(self.stack, comm, libtype) 95 96 if "callchain" in event: 97 for entry in reversed(event["callchain"]): 98 name = entry.get("sym", {}).get("name", "[unknown]") 99 libtype = self.get_libtype_from_dso(entry.get("dso")) 100 node = self.find_or_create_node(node, name, libtype) 101 else: 102 name = event.get("symbol", "[unknown]") 103 libtype = self.get_libtype_from_dso(event.get("dso")) 104 node = self.find_or_create_node(node, name, libtype) 105 node.value += 1 106 107 def get_report_header(self): 108 if self.args.input == "-": 109 # when this script is invoked with "perf script flamegraph", 110 # no perf.data is created and we cannot read the header of it 111 return "" 112 113 try: 114 output = subprocess.check_output(["perf", "report", "--header-only"]) 115 return output.decode("utf-8") 116 except Exception as err: # pylint: disable=broad-except 117 print("Error reading report header: {}".format(err), file=sys.stderr) 118 return "" 119 120 def trace_end(self): 121 stacks_json = json.dumps(self.stack, default=lambda x: x.to_json()) 122 123 if self.args.format == "html": 124 report_header = self.get_report_header() 125 options = { 126 "colorscheme": self.args.colorscheme, 127 "context": report_header 128 } 129 options_json = json.dumps(options) 130 131 try: 132 with io.open(self.args.template, encoding="utf-8") as template: 133 output_str = ( 134 template.read() 135 .replace("/** @options_json **/", options_json) 136 .replace("/** @flamegraph_json **/", stacks_json) 137 ) 138 except IOError as err: 139 print("Error reading template file: {}".format(err), file=sys.stderr) 140 sys.exit(1) 141 output_fn = self.args.output or "flamegraph.html" 142 else: 143 output_str = stacks_json 144 output_fn = self.args.output or "stacks.json" 145 146 if output_fn == "-": 147 with io.open(sys.stdout.fileno(), "w", encoding="utf-8", closefd=False) as out: 148 out.write(output_str) 149 else: 150 print("dumping data to {}".format(output_fn)) 151 try: 152 with io.open(output_fn, "w", encoding="utf-8") as out: 153 out.write(output_str) 154 except IOError as err: 155 print("Error writing output file: {}".format(err), file=sys.stderr) 156 sys.exit(1) 157 158 159if __name__ == "__main__": 160 parser = argparse.ArgumentParser(description="Create flame graphs.") 161 parser.add_argument("-f", "--format", 162 default="html", choices=["json", "html"], 163 help="output file format") 164 parser.add_argument("-o", "--output", 165 help="output file name") 166 parser.add_argument("--template", 167 default="/usr/share/d3-flame-graph/d3-flamegraph-base.html", 168 help="path to flame graph HTML template") 169 parser.add_argument("--colorscheme", 170 default="blue-green", 171 help="flame graph color scheme", 172 choices=["blue-green", "orange"]) 173 parser.add_argument("-i", "--input", 174 help=argparse.SUPPRESS) 175 176 cli_args = parser.parse_args() 177 cli = FlameGraphCLI(cli_args) 178 179 process_event = cli.process_event 180 trace_end = cli.trace_end 181