# 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>## pylint: disable=missing-module-docstring# pylint: disable=missing-class-docstring# pylint: disable=missing-function-docstring from __future__ import print_functionimport sysimport osimport ioimport argparseimport jsonimport subprocess # pylint: disable=too-few-public-methodsclass 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")         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):        """        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)             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)            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)     cli_args = parser.parse_args()    cli = FlameGraphCLI(cli_args)     process_event = cli.process_event    trace_end = cli.trace_end