[RFC v15 7/8] tools/damon: Support more human friendly 'schemes' control

From: SeongJae Park
Date: Tue Oct 06 2020 - 08:43:10 EST


From: SeongJae Park <sjpark@xxxxxxxxx>

This commit implements 'schemes' subcommand of the damon userspace tool.
It can be used to describe and apply the data access monitoring-based
operation schemes in more human friendly fashion.

Signed-off-by: SeongJae Park <sjpark@xxxxxxxxx>
---
tools/damon/_convert_damos.py | 141 ++++++++++++++++++++++++++++++++++
tools/damon/_damon.py | 28 +++++--
tools/damon/damo | 7 ++
tools/damon/schemes.py | 110 ++++++++++++++++++++++++++
4 files changed, 280 insertions(+), 6 deletions(-)
create mode 100755 tools/damon/_convert_damos.py
create mode 100644 tools/damon/schemes.py

diff --git a/tools/damon/_convert_damos.py b/tools/damon/_convert_damos.py
new file mode 100755
index 000000000000..0fd84b3701c9
--- /dev/null
+++ b/tools/damon/_convert_damos.py
@@ -0,0 +1,141 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+"""
+Change human readable data access monitoring-based operation schemes to the low
+level input for the '<debugfs>/damon/schemes' file. Below is an example of the
+schemes written in the human readable format:
+
+ # format is:
+ # <min/max size> <min/max frequency (0-100)> <min/max age> <action>
+ #
+ # B/K/M/G/T for Bytes/KiB/MiB/GiB/TiB
+ # us/ms/s/m/h/d for micro-seconds/milli-seconds/seconds/minutes/hours/days
+ # 'min/max' for possible min/max value.
+
+ # if a region keeps a high access frequency for >=100ms, put the region on
+ # the head of the LRU list (call madvise() with MADV_WILLNEED).
+ min max 80 max 100ms max willneed
+
+ # if a region keeps a low access frequency for >=200ms and <=one hour, put
+ # the region on the tail of the LRU list (call madvise() with MADV_COLD).
+ min max 10 20 200ms 1h cold
+
+ # if a region keeps a very low access frequency for >=60 seconds, swap out
+ # the region immediately (call madvise() with MADV_PAGEOUT).
+ min max 0 10 60s max pageout
+
+ # if a region of a size >=2MiB keeps a very high access frequency for
+ # >=100ms, let the region to use huge pages (call madvise() with
+ # MADV_HUGEPAGE).
+ 2M max 90 100 100ms max hugepage
+
+ # If a regions of a size >=2MiB keeps small access frequency for >=100ms,
+ # avoid the region using huge pages (call madvise() with MADV_NOHUGEPAGE).
+ 2M max 0 25 100ms max nohugepage
+"""
+
+import argparse
+import platform
+
+uint_max = 2**32 - 1
+ulong_max = 2**64 - 1
+if platform.architecture()[0] != '64bit':
+ ulong_max = 2**32 - 1
+
+unit_to_bytes = {'B': 1, 'K': 1024, 'M': 1024 * 1024, 'G': 1024 * 1024 * 1024,
+ 'T': 1024 * 1024 * 1024 * 1024}
+
+def text_to_bytes(txt):
+ if txt == 'min':
+ return 0
+ if txt == 'max':
+ return ulong_max
+
+ unit = txt[-1]
+ number = float(txt[:-1])
+ return int(number * unit_to_bytes[unit])
+
+unit_to_usecs = {'us': 1, 'ms': 1000, 's': 1000 * 1000, 'm': 60 * 1000 * 1000,
+ 'h': 60 * 60 * 1000 * 1000, 'd': 24 * 60 * 60 * 1000 * 1000}
+
+def text_to_aggr_intervals(txt, aggr_interval):
+ if txt == 'min':
+ return 0
+ if txt == 'max':
+ return uint_max
+
+ unit = txt[-2:]
+ if unit in ['us', 'ms']:
+ number = float(txt[:-2])
+ else:
+ unit = txt[-1]
+ number = float(txt[:-1])
+ return int(number * unit_to_usecs[unit]) / aggr_interval
+
+damos_action_to_int = {'DAMOS_WILLNEED': 0, 'DAMOS_COLD': 1,
+ 'DAMOS_PAGEOUT': 2, 'DAMOS_HUGEPAGE': 3, 'DAMOS_NOHUGEPAGE': 4,
+ 'DAMOS_STAT': 5}
+
+def text_to_damos_action(txt):
+ return damos_action_to_int['DAMOS_' + txt.upper()]
+
+def text_to_nr_accesses(txt, max_nr_accesses):
+ if txt == 'min':
+ return 0
+ if txt == 'max':
+ return max_nr_accesses
+
+ return int(float(txt) * max_nr_accesses / 100)
+
+def debugfs_scheme(line, sample_interval, aggr_interval):
+ fields = line.split()
+ if len(fields) != 7:
+ print('wrong input line: %s' % line)
+ exit(1)
+
+ limit_nr_accesses = aggr_interval / sample_interval
+ try:
+ min_sz = text_to_bytes(fields[0])
+ max_sz = text_to_bytes(fields[1])
+ min_nr_accesses = text_to_nr_accesses(fields[2], limit_nr_accesses)
+ max_nr_accesses = text_to_nr_accesses(fields[3], limit_nr_accesses)
+ min_age = text_to_aggr_intervals(fields[4], aggr_interval)
+ max_age = text_to_aggr_intervals(fields[5], aggr_interval)
+ action = text_to_damos_action(fields[6])
+ except:
+ print('wrong input field')
+ raise
+ return '%d\t%d\t%d\t%d\t%d\t%d\t%d' % (min_sz, max_sz, min_nr_accesses,
+ max_nr_accesses, min_age, max_age, action)
+
+def convert(schemes_file, sample_interval, aggr_interval):
+ lines = []
+ with open(schemes_file, 'r') as f:
+ for line in f:
+ if line.startswith('#'):
+ continue
+ line = line.strip()
+ if line == '':
+ continue
+ lines.append(debugfs_scheme(line, sample_interval, aggr_interval))
+ return '\n'.join(lines)
+
+def main():
+ parser = argparse.ArgumentParser()
+ parser.add_argument('input', metavar='<file>',
+ help='input file describing the schemes')
+ parser.add_argument('-s', '--sample', metavar='<interval>', type=int,
+ default=5000, help='sampling interval (us)')
+ parser.add_argument('-a', '--aggr', metavar='<interval>', type=int,
+ default=100000, help='aggregation interval (us)')
+ args = parser.parse_args()
+
+ schemes_file = args.input
+ sample_interval = args.sample
+ aggr_interval = args.aggr
+
+ print(convert(schemes_file, sample_interval, aggr_interval))
+
+if __name__ == '__main__':
+ main()
diff --git a/tools/damon/_damon.py b/tools/damon/_damon.py
index 1f6a292e8c25..a4f6c03c23e4 100644
--- a/tools/damon/_damon.py
+++ b/tools/damon/_damon.py
@@ -10,6 +10,7 @@ import subprocess

debugfs_attrs = None
debugfs_record = None
+debugfs_schemes = None
debugfs_target_ids = None
debugfs_monitor_on = None

@@ -33,8 +34,9 @@ class Attrs:
max_nr_regions = None
rbuf_len = None
rfile_path = None
+ schemes = None

- def __init__(self, s, a, r, n, x, l, f):
+ def __init__(self, s, a, r, n, x, l, f, c):
self.sample_interval = s
self.aggr_interval = a
self.regions_update_interval = r
@@ -42,12 +44,13 @@ class Attrs:
self.max_nr_regions = x
self.rbuf_len = l
self.rfile_path = f
+ self.schemes = c

def __str__(self):
- return "%s %s %s %s %s %s %s" % (self.sample_interval,
+ return "%s %s %s %s %s %s %s\n%s" % (self.sample_interval,
self.aggr_interval, self.regions_update_interval,
self.min_nr_regions, self.max_nr_regions, self.rbuf_len,
- self.rfile_path)
+ self.rfile_path, self.schemes)

def attr_str(self):
return "%s %s %s %s %s " % (self.sample_interval, self.aggr_interval,
@@ -66,6 +69,9 @@ class Attrs:
debugfs_record), shell=True, executable='/bin/bash')
if ret:
return ret
+ return subprocess.call('echo %s > %s' % (
+ self.schemes.replace('\n', ' '), debugfs_schemes), shell=True,
+ executable='/bin/bash')

def current_attrs():
with open(debugfs_attrs, 'r') as f:
@@ -77,17 +83,26 @@ def current_attrs():
attrs.append(int(rattrs[0]))
attrs.append(rattrs[1])

+ with open(debugfs_schemes, 'r') as f:
+ schemes = f.read()
+
+ # The last two fields in each line are statistics. Remove those.
+ schemes = [' '.join(x.split()[:-2]) for x in schemes.strip().split('\n')]
+ attrs.append('\n'.join(schemes))
+
return Attrs(*attrs)

def chk_update_debugfs(debugfs):
global debugfs_attrs
global debugfs_record
+ global debugfs_schemes
global debugfs_target_ids
global debugfs_monitor_on

debugfs_damon = os.path.join(debugfs, 'damon')
debugfs_attrs = os.path.join(debugfs_damon, 'attrs')
debugfs_record = os.path.join(debugfs_damon, 'record')
+ debugfs_schemes = os.path.join(debugfs_damon, 'schemes')
debugfs_target_ids = os.path.join(debugfs_damon, 'target_ids')
debugfs_monitor_on = os.path.join(debugfs_damon, 'monitor_on')

@@ -95,8 +110,8 @@ def chk_update_debugfs(debugfs):
print("damon debugfs dir (%s) not found", debugfs_damon)
exit(1)

- for f in [debugfs_attrs, debugfs_record, debugfs_target_ids,
- debugfs_monitor_on]:
+ for f in [debugfs_attrs, debugfs_record, debugfs_schemes,
+ debugfs_target_ids, debugfs_monitor_on]:
if not os.path.isfile(f):
print("damon debugfs file (%s) not found" % f)
exit(1)
@@ -112,8 +127,9 @@ def cmd_args_to_attrs(args):
if not os.path.isabs(args.out):
args.out = os.path.join(os.getcwd(), args.out)
rfile_path = args.out
+ schemes = args.schemes
return Attrs(sample_interval, aggr_interval, regions_update_interval,
- min_nr_regions, max_nr_regions, rbuf_len, rfile_path)
+ min_nr_regions, max_nr_regions, rbuf_len, rfile_path, schemes)

def set_attrs_argparser(parser):
parser.add_argument('-d', '--debugfs', metavar='<debugfs>', type=str,
diff --git a/tools/damon/damo b/tools/damon/damo
index 58e1099ae5fc..ce7180069bef 100755
--- a/tools/damon/damo
+++ b/tools/damon/damo
@@ -5,6 +5,7 @@ import argparse

import record
import report
+import schemes

class SubCmdHelpFormatter(argparse.RawDescriptionHelpFormatter):
def _format_action(self, action):
@@ -25,6 +26,10 @@ parser_record = subparser.add_parser('record',
help='record data accesses of the given target processes')
record.set_argparser(parser_record)

+parser_schemes = subparser.add_parser('schemes',
+ help='apply operation schemes to the given target process')
+schemes.set_argparser(parser_schemes)
+
parser_report = subparser.add_parser('report',
help='report the recorded data accesses in the specified form')
report.set_argparser(parser_report)
@@ -33,5 +38,7 @@ args = parser.parse_args()

if args.command == 'record':
record.main(args)
+elif args.command == 'schemes':
+ schemes.main(args)
elif args.command == 'report':
report.main(args)
diff --git a/tools/damon/schemes.py b/tools/damon/schemes.py
new file mode 100644
index 000000000000..9095835f6133
--- /dev/null
+++ b/tools/damon/schemes.py
@@ -0,0 +1,110 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+"""
+Apply given operation schemes to the target process.
+"""
+
+import argparse
+import os
+import signal
+import subprocess
+import time
+
+import _convert_damos
+import _damon
+
+def run_damon(target, is_target_cmd, attrs, old_attrs):
+ if os.path.isfile(attrs.rfile_path):
+ os.rename(attrs.rfile_path, attrs.rfile_path + '.old')
+
+ if attrs.apply():
+ print('attributes (%s) failed to be applied' % attrs)
+ cleanup_exit(old_attrs, -1)
+ print('# damon attrs: %s %s' % (attrs.attr_str(), attrs.record_str()))
+ for line in attrs.schemes.split('\n'):
+ print('# scheme: %s' % line)
+ if is_target_cmd:
+ p = subprocess.Popen(target, shell=True, executable='/bin/bash')
+ target = p.pid
+ if _damon.set_target_pid(target):
+ print('pid setting (%s) failed' % target)
+ cleanup_exit(old_attrs, -2)
+ if _damon.turn_damon('on'):
+ print('could not turn on damon' % target)
+ cleanup_exit(old_attrs, -3)
+ while not _damon.is_damon_running():
+ sleep(1)
+ print('Press Ctrl+C to stop')
+ if is_target_cmd:
+ p.wait()
+ while True:
+ # damon will turn it off by itself if the target tasks are terminated.
+ if not _damon.is_damon_running():
+ break
+ time.sleep(1)
+
+ cleanup_exit(old_attrs, 0)
+
+def cleanup_exit(orig_attrs, exit_code):
+ if _damon.is_damon_running():
+ if _damon.turn_damon('off'):
+ print('failed to turn damon off!')
+ while _damon.is_damon_running():
+ sleep(1)
+ if orig_attrs:
+ if orig_attrs.apply():
+ print('original attributes (%s) restoration failed!' % orig_attrs)
+ exit(exit_code)
+
+def sighandler(signum, frame):
+ print('\nsignal %s received' % signum)
+ cleanup_exit(orig_attrs, signum)
+
+def chk_permission():
+ if os.geteuid() != 0:
+ print("Run as root")
+ exit(1)
+
+def set_argparser(parser):
+ _damon.set_attrs_argparser(parser)
+ parser.add_argument('target', type=str, metavar='<target>',
+ help='the target command or the pid to record')
+ parser.add_argument('-c', '--schemes', metavar='<file>', type=str,
+ default='damon.schemes',
+ help='data access monitoring-based operation schemes')
+
+def main(args=None):
+ global orig_attrs
+ if not args:
+ parser = argparse.ArgumentParser()
+ set_argparser(parser)
+ args = parser.parse_args()
+
+ chk_permission()
+ _damon.chk_update_debugfs(args.debugfs)
+
+ signal.signal(signal.SIGINT, sighandler)
+ signal.signal(signal.SIGTERM, sighandler)
+ orig_attrs = _damon.current_attrs()
+
+ args.rbuf = 0
+ args.out = 'null'
+ args.schemes = _convert_damos.convert(args.schemes, args.sample, args.aggr)
+ new_attrs = _damon.cmd_args_to_attrs(args)
+ target = args.target
+
+ target_fields = target.split()
+ if not subprocess.call('which %s &> /dev/null' % target_fields[0],
+ shell=True, executable='/bin/bash'):
+ run_damon(target, True, new_attrs, orig_attrs)
+ else:
+ try:
+ pid = int(target)
+ except:
+ print('target \'%s\' is neither a command, nor a pid' % target)
+ exit(1)
+ run_damon(target, False, new_attrs, orig_attrs)
+
+if __name__ == '__main__':
+ main()
--
2.17.1