perf scripts python: Add new compaction-times script

This patch creates a new script (compaction-times) to report time
spent in mm compaction. It is possible to report times in nanoseconds
(default) or microseconds (-u).

The option -p will break down results by process id, -pv will further
decompose by each compaction entry/exit.

For each compaction entry/exit what is reported is controlled by the
options:

  -t   report only timing
  -m   report migration stats
  -ms  report migration scanner stats
  -fs  report free scanner stats

The default is to report all.

Entries may be further filtered by pid, pid-range or comm (regex).

The script is useful when analysing workloads that compact memory. The
most common example will be THP allocations on systems with a lot of
uptime that has fragmented memory.

This is an example of using the script to analyse a thpscale from
mmtests which deliberately fragments memory and allocates THP in 4
separate threads

  # Recording step, one of the following;
  $ perf record -e 'compaction:mm_compaction_*' ./workload
  # or:
  $ perf script record compaction-times

  # Reporting: basic
  total: 2444505743ns migration: moved=357738 failed=39275
  free_scanner: scanned=2705578 isolated=387875
  migration_scanner: scanned=414426 isolated=397013

  # Reporting: Per task stall times
  $ perf script report compaction-times -- -t -p
  total: 2444505743ns
  6384[thpscale]: 740800017ns
  6385[thpscale]: 274119512ns
  6386[thpscale]: 832961337ns
  6383[thpscale]: 596624877ns

  # Reporting: Per-compaction attempts for task 6385
  $ perf script report compaction-times -- -m -pv 6385
  total: 274119512ns migration: moved=14893 failed=24285
  6385[thpscale]: 274119512ns migration: moved=14893 failed=24285
  6385[thpscale].1: 3033277ns migration: moved=511 failed=1
  6385[thpscale].2: 9592094ns migration: moved=1524 failed=12
  6385[thpscale].3: 2495587ns migration: moved=512 failed=0
  6385[thpscale].4: 2561766ns migration: moved=512 failed=0
  6385[thpscale].5: 2523521ns migration: moved=512 failed=0
  ..... output continues ...

Changes since v1:
- report stats for isolate_migratepages and isolate_freepages
  (Vlastimil Babka)
- refactor code to achieve above
- add help text
- output to stdout/stderr explicitly

Signed-off-by: Tony Jones <tonyj@suse.com>
Cc: Mel Gorman <mgorman@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: http://lkml.kernel.org/r/1439840932-8933-1-git-send-email-tonyj@suse.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/scripts/python/bin/compaction-times-record

@@ -0,0 +1,2 @@
+#!/bin/bash
+perf record -e compaction:mm_compaction_begin -e compaction:mm_compaction_end -e compaction:mm_compaction_migratepages -e compaction:mm_compaction_isolate_migratepages -e compaction:mm_compaction_isolate_freepages $@

tools/perf/scripts/python/bin/compaction-times-report

@@ -0,0 +1,4 @@
+#!/bin/bash
+#description: display time taken by mm compaction
+#args: [-h] [-u] [-p|-pv] [-t | [-m] [-fs] [-ms]] [pid|pid-range|comm-regex]
+perf script -s "$PERF_EXEC_PATH"/scripts/python/compaction-times.py $@

tools/perf/scripts/python/compaction-times.py

@@ -0,0 +1,311 @@
+# report time spent in compaction
+# Licensed under the terms of the GNU GPL License version 2
+
+# testing:
+# 'echo 1 > /proc/sys/vm/compact_memory' to force compaction of all zones
+
+import os
+import sys
+import re
+
+import signal
+signal.signal(signal.SIGPIPE, signal.SIG_DFL)
+
+usage = "usage: perf script report compaction-times.py -- [-h] [-u] [-p|-pv] [-t | [-m] [-fs] [-ms]] [pid|pid-range|comm-regex]\n"
+
+class popt:
+	DISP_DFL = 0
+	DISP_PROC = 1
+	DISP_PROC_VERBOSE=2
+
+class topt:
+	DISP_TIME = 0
+	DISP_MIG = 1
+	DISP_ISOLFREE = 2
+	DISP_ISOLMIG = 4
+	DISP_ALL = 7
+
+class comm_filter:
+	def __init__(self, re):
+		self.re = re
+
+	def filter(self, pid, comm):
+		m = self.re.search(comm)
+		return m == None or m.group() == ""
+
+class pid_filter:
+	def __init__(self, low, high):
+		self.low = (0 if low == "" else int(low))
+		self.high = (0 if high == "" else int(high))
+
+	def filter(self, pid, comm):
+		return not (pid >= self.low and (self.high == 0 or pid <= self.high))
+
+def set_type(t):
+	global opt_disp
+	opt_disp = (t if opt_disp == topt.DISP_ALL else opt_disp|t)
+
+def ns(sec, nsec):
+	return (sec * 1000000000) + nsec
+
+def time(ns):
+	return "%dns" % ns if opt_ns else "%dus" % (round(ns, -3) / 1000)
+
+class pair:
+	def __init__(self, aval, bval, alabel = None, blabel = None):
+		self.alabel = alabel
+		self.blabel = blabel
+		self.aval = aval
+		self.bval = bval
+
+	def __add__(self, rhs):
+		self.aval += rhs.aval
+		self.bval += rhs.bval
+		return self
+
+	def __str__(self):
+		return "%s=%d %s=%d" % (self.alabel, self.aval, self.blabel, self.bval)
+
+class cnode:
+	def __init__(self, ns):
+		self.ns = ns
+		self.migrated = pair(0, 0, "moved", "failed")
+		self.fscan = pair(0,0, "scanned", "isolated")
+		self.mscan = pair(0,0, "scanned", "isolated")
+
+	def __add__(self, rhs):
+		self.ns += rhs.ns
+		self.migrated += rhs.migrated
+		self.fscan += rhs.fscan
+		self.mscan += rhs.mscan
+		return self
+
+	def __str__(self):
+		prev = 0
+		s = "%s " % time(self.ns)
+		if (opt_disp & topt.DISP_MIG):
+			s += "migration: %s" % self.migrated
+			prev = 1
+		if (opt_disp & topt.DISP_ISOLFREE):
+			s += "%sfree_scanner: %s" % (" " if prev else "", self.fscan)
+			prev = 1
+		if (opt_disp & topt.DISP_ISOLMIG):
+			s += "%smigration_scanner: %s" % (" " if prev else "", self.mscan)
+		return s
+
+	def complete(self, secs, nsecs):
+		self.ns = ns(secs, nsecs) - self.ns
+
+	def increment(self, migrated, fscan, mscan):
+		if (migrated != None):
+			self.migrated += migrated
+		if (fscan != None):
+			self.fscan += fscan
+		if (mscan != None):
+			self.mscan += mscan
+
+
+class chead:
+	heads = {}
+	val = cnode(0);
+	fobj = None
+
+	@classmethod
+	def add_filter(cls, filter):
+		cls.fobj = filter
+
+	@classmethod
+	def create_pending(cls, pid, comm, start_secs, start_nsecs):
+		filtered = 0
+		try:
+			head = cls.heads[pid]
+			filtered = head.is_filtered()
+		except KeyError:
+			if cls.fobj != None:
+				filtered = cls.fobj.filter(pid, comm)
+			head = cls.heads[pid] = chead(comm, pid, filtered)
+
+		if not filtered:
+			head.mark_pending(start_secs, start_nsecs)
+
+	@classmethod
+	def increment_pending(cls, pid, migrated, fscan, mscan):
+		head = cls.heads[pid]
+		if not head.is_filtered():
+			if head.is_pending():
+				head.do_increment(migrated, fscan, mscan)
+			else:
+				sys.stderr.write("missing start compaction event for pid %d\n" % pid)
+
+	@classmethod
+	def complete_pending(cls, pid, secs, nsecs):
+		head = cls.heads[pid]
+		if not head.is_filtered():
+			if head.is_pending():
+				head.make_complete(secs, nsecs)
+			else:
+				sys.stderr.write("missing start compaction event for pid %d\n" % pid)
+
+	@classmethod
+	def gen(cls):
+		if opt_proc != popt.DISP_DFL:
+			for i in cls.heads:
+				yield cls.heads[i]
+
+	@classmethod
+	def str(cls):
+		return cls.val
+
+	def __init__(self, comm, pid, filtered):
+		self.comm = comm
+		self.pid = pid
+		self.val = cnode(0)
+		self.pending = None
+		self.filtered = filtered
+		self.list = []
+
+	def __add__(self, rhs):
+		self.ns += rhs.ns
+		self.val += rhs.val
+		return self
+
+	def mark_pending(self, secs, nsecs):
+		self.pending = cnode(ns(secs, nsecs))
+
+	def do_increment(self, migrated, fscan, mscan):
+		self.pending.increment(migrated, fscan, mscan)
+
+	def make_complete(self, secs, nsecs):
+		self.pending.complete(secs, nsecs)
+		chead.val += self.pending
+
+		if opt_proc != popt.DISP_DFL:
+			self.val += self.pending
+
+			if opt_proc == popt.DISP_PROC_VERBOSE:
+				self.list.append(self.pending)
+		self.pending = None
+
+	def enumerate(self):
+		if opt_proc == popt.DISP_PROC_VERBOSE and not self.is_filtered():
+			for i, pelem in enumerate(self.list):
+				sys.stdout.write("%d[%s].%d: %s\n" % (self.pid, self.comm, i+1, pelem))
+
+	def is_pending(self):
+		return self.pending != None
+
+	def is_filtered(self):
+		return self.filtered
+
+	def display(self):
+		if not self.is_filtered():
+			sys.stdout.write("%d[%s]: %s\n" % (self.pid, self.comm, self.val))
+
+
+def trace_end():
+	sys.stdout.write("total: %s\n" % chead.str())
+	for i in chead.gen():
+		i.display(),
+		i.enumerate()
+
+def compaction__mm_compaction_migratepages(event_name, context, common_cpu,
+	common_secs, common_nsecs, common_pid, common_comm,
+	common_callchain, nr_migrated, nr_failed):
+
+	chead.increment_pending(common_pid,
+		pair(nr_migrated, nr_failed), None, None)
+
+def compaction__mm_compaction_isolate_freepages(event_name, context, common_cpu,
+        common_secs, common_nsecs, common_pid, common_comm,
+        common_callchain, start_pfn, end_pfn, nr_scanned, nr_taken):
+
+	chead.increment_pending(common_pid,
+		None, pair(nr_scanned, nr_taken), None)
+
+def compaction__mm_compaction_isolate_migratepages(event_name, context, common_cpu,
+        common_secs, common_nsecs, common_pid, common_comm,
+        common_callchain, start_pfn, end_pfn, nr_scanned, nr_taken):
+
+	chead.increment_pending(common_pid,
+		None, None, pair(nr_scanned, nr_taken))
+
+def compaction__mm_compaction_end(event_name, context, common_cpu,
+	common_secs, common_nsecs, common_pid, common_comm,
+	common_callchain, zone_start, migrate_start, free_start, zone_end,
+	sync, status):
+
+	chead.complete_pending(common_pid, common_secs, common_nsecs)
+
+def compaction__mm_compaction_begin(event_name, context, common_cpu,
+	common_secs, common_nsecs, common_pid, common_comm,
+	common_callchain, zone_start, migrate_start, free_start, zone_end,
+	sync):
+
+	chead.create_pending(common_pid, common_comm, common_secs, common_nsecs)
+
+def pr_help():
+	global usage
+
+	sys.stdout.write(usage)
+	sys.stdout.write("\n")
+	sys.stdout.write("-h	display this help\n")
+	sys.stdout.write("-p	display by process\n")
+	sys.stdout.write("-pv	display by process (verbose)\n")
+	sys.stdout.write("-t	display stall times only\n")
+	sys.stdout.write("-m	display stats for migration\n")
+	sys.stdout.write("-fs	display stats for free scanner\n")
+	sys.stdout.write("-ms	display stats for migration scanner\n")
+	sys.stdout.write("-u	display results in microseconds (default nanoseconds)\n")
+
+
+comm_re = None
+pid_re = None
+pid_regex = "^(\d*)-(\d*)$|^(\d*)$"
+
+opt_proc = popt.DISP_DFL
+opt_disp = topt.DISP_ALL
+
+opt_ns = True
+
+argc = len(sys.argv) - 1
+if argc >= 1:
+	pid_re = re.compile(pid_regex)
+
+	for i, opt in enumerate(sys.argv[1:]):
+		if opt[0] == "-":
+			if opt == "-h":
+				pr_help()
+				exit(0);
+			elif opt == "-p":
+				opt_proc = popt.DISP_PROC
+			elif opt == "-pv":
+				opt_proc = popt.DISP_PROC_VERBOSE
+			elif opt == '-u':
+				opt_ns = False
+			elif opt == "-t":
+				set_type(topt.DISP_TIME)
+			elif opt == "-m":
+				set_type(topt.DISP_MIG)
+			elif opt == "-fs":
+				set_type(topt.DISP_ISOLFREE)
+			elif opt == "-ms":
+				set_type(topt.DISP_ISOLMIG)
+			else:
+				sys.exit(usage)
+
+		elif i == argc - 1:
+			m = pid_re.search(opt)
+			if m != None and m.group() != "":
+				if m.group(3) != None:
+					f = pid_filter(m.group(3), m.group(3))
+				else:
+					f = pid_filter(m.group(1), m.group(2))
+			else:
+				try:
+					comm_re=re.compile(opt)
+				except:
+					sys.stderr.write("invalid regex '%s'" % opt)
+					sys.exit(usage)
+				f = comm_filter(comm_re)
+
+			chead.add_filter(f)