diff options
Diffstat (limited to 'tools/perf/python/sctop.py')
| -rwxr-xr-x | tools/perf/python/sctop.py | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/tools/perf/python/sctop.py b/tools/perf/python/sctop.py new file mode 100755 index 000000000000..48320af8b755 --- /dev/null +++ b/tools/perf/python/sctop.py @@ -0,0 +1,253 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 +""" +System call top + +Periodically displays system-wide system call totals, broken down by +syscall. If a [comm] arg is specified, only syscalls called by +[comm] are displayed. If an [interval] arg is specified, the display +will be refreshed every [interval] seconds. The default interval is +3 seconds. + +Ported from tools/perf/scripts/python/sctop.py +""" +from __future__ import annotations + +import argparse +from collections import defaultdict +import os +import sys +import threading +from typing import Optional +import perf +from perf_live import LiveSession + + +class SCTopAnalyzer: + """Periodically displays system-wide system call totals.""" + + def __init__(self, for_comm: Optional[str], interval: int, offline: bool = False): + self.for_comm = for_comm + self.interval = interval + self.syscalls: dict[int, int] = defaultdict(int) + self.comm_cache: dict[int, str] = {} + self.lock = threading.Lock() + self.stop_event = threading.Event() + self.thread = threading.Thread(target=self.print_syscall_totals) + self.offline = offline + self.own_pid = os.getpid() + self.last_print_time: Optional[int] = None + self.printed = False + self.session: Optional[perf.session] = None + self.e_machine: Optional[int] = None + + def syscall_name(self, syscall_id: int) -> str: + """Lookup syscall name by ID.""" + # Mask out the x86_64 x32 ABI bit (__X32_SYSCALL_BIT = 0x40000000) before + # resolving the syscall number in the architecture's syscall table. + raw_sc_id = syscall_id & ~0x40000000 + try: + e_machine = getattr(self.session, "e_machine", self.e_machine) + if e_machine is not None: + name = perf.syscall_name(raw_sc_id, e_machine) + else: + name = perf.syscall_name(raw_sc_id) + if name is not None: + return name + except (TypeError, OverflowError): + pass + return str(syscall_id) + + def process_event(self, sample: perf.sample_event) -> None: + """Collect syscall events.""" + if not self.offline and sample.sample_pid == self.own_pid: + return + + name = str(sample.evsel) + # Per-syscall syscalls:sys_enter_* tracepoints expose '__syscall_nr' (or 'nr') + # and may have an unrelated syscall argument named 'id', whereas + # raw_syscalls:sys_enter (and legacy pre-2.6.35 syscalls:sys_enter) expose 'id'. + if name.startswith("evsel(syscalls:sys_enter_"): + syscall_id = getattr(sample, "__syscall_nr", -1) + if not (0 <= (syscall_id & ~0x40000000) <= 0xffff): + syscall_id = getattr(sample, "nr", -1) + elif name.startswith(("evsel(raw_syscalls:sys_enter", "evsel(syscalls:sys_enter")): + syscall_id = getattr(sample, "id", -1) + if not (0 <= (syscall_id & ~0x40000000) <= 0xffff): + syscall_id = getattr(sample, "__syscall_nr", -1) + if not (0 <= (syscall_id & ~0x40000000) <= 0xffff): + syscall_id = getattr(sample, "nr", -1) + else: + syscall_id = -1 + + skip = False + with self.lock: + if self.for_comm is not None: + is_execve = (0 <= (syscall_id & ~0x40000000) <= 0xffff and + self.syscall_name(syscall_id) in ("execve", "execveat")) + if is_execve: + self.comm_cache.pop(sample.sample_pid, None) + + comm = "Unknown" + if hasattr(self, 'session') and self.session: + # In offline perf.data mode, query session.find_thread() directly + # so PERF_RECORD_COMM updates after execve (e.g. perf -> sleep) + # are reflected immediately rather than returning a stale cached comm. + try: + proc = self.session.find_thread(sample.sample_pid, sample.sample_tid) + if proc: + comm = proc.comm() or "Unknown" + except TypeError: + pass + if comm != "Unknown" and not is_execve: + self.comm_cache[sample.sample_pid] = comm + elif sample.sample_pid in self.comm_cache: + comm = self.comm_cache[sample.sample_pid] + elif sample.sample_pid in self.comm_cache: + comm = self.comm_cache[sample.sample_pid] + else: + try: + with open(f"/proc/{sample.sample_pid}/comm", "r", + encoding="utf-8", errors="replace") as f: + comm = f.read().strip() + except OSError: + comm = "Unknown" + # Cache both matching and non-matching comms (including "Unknown" + # when a PID has exited or is inaccessible) so live system-wide + # tracing does not re-open /proc/<pid>/comm on every syscall. + # Do not cache during sys_enter(execve/execveat) since /proc/<pid>/comm + # still holds the pre-exec command name until the syscall completes. + if not is_execve: + self.comm_cache[sample.sample_pid] = comm + + if comm != self.for_comm: + skip = True + + is_enter = (name.startswith("evsel(raw_syscalls:sys_enter") or + name.startswith("evsel(syscalls:sys_enter")) + if not skip and is_enter and 0 <= (syscall_id & ~0x40000000) <= 0xffff: + self.syscalls[syscall_id] += 1 + + if self.offline and hasattr(sample, "sample_time"): + interval_ns = self.interval * (10 ** 9) + if self.last_print_time is None: + self.last_print_time = sample.sample_time + elif sample.sample_time - self.last_print_time >= interval_ns: + self.print_current_totals() + self.last_print_time = sample.sample_time + + def print_current_totals(self): + """Print current syscall totals.""" + self.printed = True + # Clear terminal + if not self.offline: + print("\x1b[2J\x1b[H", end="") + else: + print() + + with self.lock: + for_comm = self.for_comm + if for_comm is not None: + print(f"\nsyscall events for {for_comm}:\n") + else: + print("\nsyscall events:\n") + + print(f"{'event':40s} {'count':10s}") + print(f"{'-' * 40:40s} {'-' * 10:10s}") + + with self.lock: + current_syscalls = list(self.syscalls.items()) + self.syscalls.clear() + self.comm_cache.clear() + + current_syscalls.sort(key=lambda kv: (-kv[1], kv[0])) + + for syscall_id, val in current_syscalls: + print(f"{self.syscall_name(syscall_id):<40s} {val:10d}") + + def print_syscall_totals(self): + """Periodically print syscall totals.""" + while not self.stop_event.is_set(): + self.print_current_totals() + self.stop_event.wait(self.interval) + # Print final batch + self.print_current_totals() + + def start(self): + """Start the background thread.""" + self.thread.start() + + def stop(self): + """Stop the background thread.""" + self.stop_event.set() + self.thread.join() + + +def main(): + """Main function.""" + ap = argparse.ArgumentParser(description="System call top") + ap.add_argument("args", nargs="*", help="[comm] [interval] or [interval]") + ap.add_argument("-i", "--input", help="Input file name") + args = ap.parse_args() + + for_comm = None + default_interval = 3 + interval = default_interval + + if len(args.args) > 2: + print("Usage: python sctop.py [comm] [interval]") + sys.exit(1) + + if len(args.args) > 1: + for_comm = args.args[0] + try: + interval = int(args.args[1]) + except ValueError: + print(f"Invalid interval: {args.args[1]}") + sys.exit(1) + elif len(args.args) > 0: + try: + interval = int(args.args[0]) + except ValueError: + for_comm = args.args[0] + interval = default_interval + + analyzer = SCTopAnalyzer(for_comm, interval, offline=bool(args.input)) + session = None + + try: + if args.input: + session = perf.session(perf.data(args.input), sample=analyzer.process_event) + analyzer.session = session + analyzer.e_machine = getattr(session, "e_machine", None) + session.process_events() + else: + try: + live_session = LiveSession( + "raw_syscalls:sys_enter", sample_callback=analyzer.process_event + ) + except OSError: + live_session = LiveSession( + "syscalls:sys_enter_*", sample_callback=analyzer.process_event + ) + analyzer.start() + live_session.run() + except KeyboardInterrupt: + pass + except (OSError, IOError) as e: + print(f"Error: {e}", file=sys.stderr) + sys.exit(1) + finally: + if args.input: + if not analyzer.printed or analyzer.syscalls: + analyzer.print_current_totals() + # Break the reference cycle between perf.session and analyzer.process_event + # because perf.session lacks cyclic GC support (tp_traverse). + analyzer.session = None + session = None + elif analyzer.thread.is_alive(): + analyzer.stop() + + +if __name__ == "__main__": + main() |