linux/tools/perf/python/syscall-counts.py
Ian Rogers 3d69731960 perf python: Port syscall-counts to perf module
Port tools/perf/scripts/python/syscall-counts.py to a standalone script
in tools/perf/python/ using the perf module. Avoiding the embedded
interpreter and per-event dictionary allocation overhead improves
execution speed by ~4x:

```
$ perf record -e raw_syscalls:sys_enter -a sleep 1
...
$ time perf script tools/perf/scripts/python/syscall-counts.py perf
...
real    0m3.887s
user    0m3.578s
sys     0m0.308s
$ time python3 tools/perf/python/syscall-counts.py perf
...
real    0m0.953s
user    0m0.905s
sys     0m0.048s
```

Additional improvements compared to the legacy script:
- Resolve syscall names using perf.syscall_name(id, session.e_machine)
  instead of host python-audit / Util.py tables, enabling accurate
  cross-architecture perf.data analysis without external dependencies.
- Support both raw_syscalls:sys_enter (sample.id) and individual
  syscalls:sys_enter_* tracepoints (sample.__syscall_nr / sample.nr),
  filtering out invalid/corrupt (> 0xffff or negative) syscall numbers.
- Add argparse CLI options (-i/--input and optional comm filter).

Add a shell test (test_syscall_counts_python.sh) to verify the
standalone script. The legacy script and its bin wrapper are retained
temporarily during the transition to maintain bisectability and are
removed once all scripts are migrated.

Assisted-by: Antigravity:gemini-3.1-pro
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-09-26 20:49:29 +02:00

96 lines
3.4 KiB
Python
Executable File

#!/usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0
"""
Displays system-wide system call totals, broken down by syscall.
If a [comm] arg is specified, only syscalls called by [comm] are displayed.
"""
from __future__ import annotations
import argparse
from collections import defaultdict
from typing import DefaultDict
import perf
syscalls: DefaultDict[int, int] = defaultdict(int)
for_comm = None
session = None
def print_syscall_totals():
"""Print aggregated statistics."""
if for_comm is not None:
print(f"\nsyscall events for {for_comm}:\n")
else:
print("\nsyscall events:\n")
print(f"{'event':<40} {'count':>10}")
print("---------------------------------------- -----------")
for sc_id, val in sorted(syscalls.items(),
key=lambda kv: (-kv[1], kv[0])):
e_machine = getattr(session, "e_machine", 0) or 0
# 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 = sc_id & ~0x40000000
if e_machine:
name = perf.syscall_name(raw_sc_id, e_machine) or str(sc_id)
else:
name = perf.syscall_name(raw_sc_id) or str(sc_id)
print(f"{name:<40} {val:>10}")
def process_event(sample):
"""Process a single sample event."""
event_name = str(sample.evsel)
# Per-syscall syscalls:sys_enter_* tracepoints expose '__syscall_nr' (or 'nr')
# and may have an unrelated syscall argument named 'id' (e.g. sys_enter_clock_gettime),
# whereas raw_syscalls:sys_enter (and legacy pre-2.6.35 syscalls:sys_enter) expose 'id'.
if event_name.startswith("evsel(syscalls:sys_enter_"):
sc_id = getattr(sample, "__syscall_nr", None)
if sc_id is not None and not (0 <= (sc_id & ~0x40000000) <= 0xffff):
sc_id = None
if sc_id is None:
sc_id = getattr(sample, "nr", -1)
elif event_name.startswith(("evsel(raw_syscalls:sys_enter", "evsel(syscalls:sys_enter")):
sc_id = getattr(sample, "id", -1)
if not (0 <= (sc_id & ~0x40000000) <= 0xffff):
sc_id = getattr(sample, "__syscall_nr", -1)
if not (0 <= (sc_id & ~0x40000000) <= 0xffff):
sc_id = getattr(sample, "nr", -1)
else:
return
# Mask out __X32_SYSCALL_BIT (0x40000000) when validating the syscall ID range.
if not (0 <= (sc_id & ~0x40000000) <= 0xffff):
return
comm = "unknown"
try:
if session:
proc = session.find_thread(sample.sample_pid, sample.sample_tid)
if proc:
comm = proc.comm() or "unknown"
except (TypeError, AttributeError):
pass
if for_comm and comm != for_comm:
return
syscalls[sc_id] += 1
if __name__ == "__main__":
ap = argparse.ArgumentParser()
ap.add_argument("comm", nargs="?", help="Only report syscalls for comm")
ap.add_argument("-i", "--input", default="perf.data", help="Input file name")
args = ap.parse_args()
for_comm = args.comm
try:
session = perf.session(perf.data(args.input), sample=process_event)
session.process_events()
print_syscall_totals()
finally:
# Break the reference cycle between session and process_event (whose module
# globals reference session) since perf.session lacks cyclic GC (tp_traverse).
session = None