# 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_functionimport sysimport osimport ioimport argparseimport 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 io.open(self.args.template, encoding="utf-8") 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 == "-":            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 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