diff --git a/tools/perf/python/rw-by-file.py b/tools/perf/python/rw-by-file.py new file mode 100755 index 000000000000..b33330261606 --- /dev/null +++ b/tools/perf/python/rw-by-file.py @@ -0,0 +1,113 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0-only +"""Display r/w activity for files read/written to for a given program.""" +from __future__ import annotations + +import argparse +from collections import defaultdict +import sys +from typing import Optional, Dict +import perf + +class RwByFile: + """Tracks and displays read/write activity by file descriptor.""" + def __init__(self, comm: str) -> None: + self.for_comm = comm + self.reads: Dict[int, Dict[str, int]] = defaultdict( + lambda: {"bytes_requested": 0, "total_reads": 0} + ) + self.writes: Dict[int, Dict[str, int]] = defaultdict( + lambda: {"bytes_written": 0, "total_writes": 0} + ) + self.unhandled: Dict[str, int] = defaultdict(int) + self.session: Optional[perf.session] = None + + def process_event(self, sample: perf.sample_event) -> None: + """Process events.""" + event_name = str(sample.evsel) + if event_name.startswith("evsel(") and event_name.endswith(")"): + event_name = event_name[6:-1] + event_name = "".join(c if c.isprintable() else "?" for c in event_name) + + pid = sample.sample_pid + assert self.session is not None + try: + thread = self.session.find_thread(pid, sample.sample_tid) + comm = (thread.comm() if thread else None) or "unknown" + except (TypeError, AttributeError): + comm = "unknown" + + if comm != self.for_comm: + return + + if event_name == "syscalls:sys_enter_read": + try: + fd = sample.fd + count = sample.count + self.reads[fd]["bytes_requested"] += count + self.reads[fd]["total_reads"] += 1 + except AttributeError: + self.unhandled[event_name] += 1 + elif event_name == "syscalls:sys_enter_write": + try: + fd = sample.fd + count = sample.count + self.writes[fd]["bytes_written"] += count + self.writes[fd]["total_writes"] += 1 + except AttributeError: + self.unhandled[event_name] += 1 + else: + self.unhandled[event_name] += 1 + + def print_totals(self) -> None: + """Print summary tables.""" + print(f"file read counts for {self.for_comm}:\n") + print(f"{'fd':>6s} {'# reads':>10s} {'bytes_requested':>15s}") + print(f"{'-'*6} {'-'*10} {'-'*15}") + + for fd, data in sorted(self.reads.items(), + key=lambda kv: kv[1]["bytes_requested"], reverse=True): + print(f"{fd:6d} {data['total_reads']:10d} {data['bytes_requested']:15d}") + + print(f"\nfile write counts for {self.for_comm}:\n") + print(f"{'fd':>6s} {'# writes':>10s} {'bytes_written':>15s}") + print(f"{'-'*6} {'-'*10} {'-'*15}") + + for fd, data in sorted(self.writes.items(), + key=lambda kv: kv[1]["bytes_written"], reverse=True): + print(f"{fd:6d} {data['total_writes']:10d} {data['bytes_written']:15d}") + + if self.unhandled: + print("\nunhandled events:\n") + print(f"{'event':<40s} {'count':>10s}") + print(f"{'-'*40} {'-'*10}") + for event_name, count in self.unhandled.items(): + print(f"{event_name:<40s} {count:10d}") + + def run(self, input_file: str) -> None: + """Run the session.""" + self.session = perf.session(perf.data(input_file), sample=self.process_event) + try: + self.session.process_events() + finally: + # Break the reference cycle between perf.session and self.process_event + # because perf.session lacks cyclic GC support (tp_traverse). + self.session = None + self.print_totals() + +def main() -> None: + """Main function.""" + parser = argparse.ArgumentParser(description="Trace r/w activity by file") + parser.add_argument("comm", help="Filter by command name") + parser.add_argument("-i", "--input", default="perf.data", help="Input file") + args = parser.parse_args() + + analyzer = RwByFile(args.comm) + try: + analyzer.run(args.input) + except IOError as e: + print(e, file=sys.stderr) + sys.exit(1) + +if __name__ == "__main__": + main() diff --git a/tools/perf/tests/shell/test_rw_by_file_python.sh b/tools/perf/tests/shell/test_rw_by_file_python.sh new file mode 100755 index 000000000000..98218bf8a39e --- /dev/null +++ b/tools/perf/tests/shell/test_rw_by_file_python.sh @@ -0,0 +1,68 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# rw-by-file python test + +set -e + +shelldir=$(dirname "$0") +# shellcheck source=lib/setup_python.sh +. "${shelldir}"/lib/setup_python.sh + +if ! "$PYTHON" -c 'import perf' > /dev/null 2>&1; then + echo "Skipping test, perf python module not found" + exit 2 +fi + +script_dir="$(dirname "$0")/../../python" +script_path="${script_dir}/rw-by-file.py" + +if ! perf check feature -q libtraceevent > /dev/null 2>&1; then + echo "Skipping test, libtraceevent is disabled" + exit 2 +fi + +if [ ! -f "$script_path" ]; then + echo "Skipping test, rw-by-file.py not found at $script_path" + exit 2 +fi + +err=0 +cleanup() { + rm -f "${temp_data}" "${temp_out}" +} +trap 'cleanup' EXIT TERM INT +temp_data=$(mktemp /tmp/perf.data.XXXXXX) +temp_out=$(mktemp /tmp/perf.out.XXXXXX) + +echo "Testing rw-by-file.py..." + +# Create a perf.data file. Try to get tracepoint data. +if perf list | grep -q "syscalls:sys_enter_read"; then + perf record -e syscalls:sys_enter_read,syscalls:sys_enter_write -a -o "${temp_data}" \ + -- dd if=/dev/urandom of=/dev/null bs=1M count=10 >/dev/null 2>&1 || \ + { echo "Skipping test, perf record failed"; exit 2; } +else + echo "Skipping test, no syscalls:sys_enter_read event" + exit 2 +fi + +if [ ! -s "${temp_data}" ]; then + echo "Skipping test, perf record failed to create data" + exit 2 +fi + +# Check that the script executes - filtering for "dd" since that's what we ran +if ! "$PYTHON" "$script_path" -i "${temp_data}" "dd" > "${temp_out}"; then + echo "rw-by-file.py test failed" + err=1 +else + if ! grep -E -q "^ *[0-9]+" "${temp_out}"; then + echo "Failed to find metric data rows" + err=1 + else + echo "rw-by-file test passed." + fi +fi +rm -f "${temp_out}" + +exit $err