diff options
Diffstat (limited to 'contrib/gen_autofdo_event.py')
-rwxr-xr-x | contrib/gen_autofdo_event.py | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/contrib/gen_autofdo_event.py b/contrib/gen_autofdo_event.py new file mode 100755 index 00000000000..3865cbb2ee5 --- /dev/null +++ b/contrib/gen_autofdo_event.py @@ -0,0 +1,155 @@ +#!/usr/bin/python +# Generate Intel taken branches Linux perf event script for autofdo profiling. + +# Copyright (C) 2016 Free Software Foundation, Inc. +# +# GCC is free software; you can redistribute it and/or modify it under +# the terms of the GNU General Public License as published by the Free +# Software Foundation; either version 3, or (at your option) any later +# version. +# +# GCC is distributed in the hope that it will be useful, but WITHOUT ANY +# WARRANTY; without even the implied warranty of MERCHANTABILITY or +# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +# for more details. +# +# You should have received a copy of the GNU General Public License +# along with GCC; see the file COPYING3. If not see +# <http://www.gnu.org/licenses/>. */ + +# Run it with perf record -b -e EVENT program ... +# The Linux Kernel needs to support the PMU of the current CPU, and +# It will likely not work in VMs. +# Add --all to print for all cpus, otherwise for current cpu. +# Add --script to generate shell script to run correct event. +# +# Requires internet (https) access. This may require setting up a proxy +# with export https_proxy=... +# +import urllib2 +import sys +import json +import argparse +import collections + +baseurl = "https://download.01.org/perfmon" + +target_events = (u'BR_INST_RETIRED.NEAR_TAKEN', + u'BR_INST_EXEC.TAKEN', + u'BR_INST_RETIRED.TAKEN_JCC', + u'BR_INST_TYPE_RETIRED.COND_TAKEN') + +ap = argparse.ArgumentParser() +ap.add_argument('--all', '-a', help='Print for all CPUs', action='store_true') +ap.add_argument('--script', help='Generate shell script', action='store_true') +args = ap.parse_args() + +eventmap = collections.defaultdict(list) + +def get_cpu_str(): + with open('/proc/cpuinfo', 'r') as c: + vendor, fam, model = None, None, None + for j in c: + n = j.split() + if n[0] == 'vendor_id': + vendor = n[2] + elif n[0] == 'model' and n[1] == ':': + model = int(n[2]) + elif n[0] == 'cpu' and n[1] == 'family': + fam = int(n[3]) + if vendor and fam and model: + return "%s-%d-%X" % (vendor, fam, model), model + return None, None + +def find_event(eventurl, model): + print >>sys.stderr, "Downloading", eventurl + u = urllib2.urlopen(eventurl) + events = json.loads(u.read()) + u.close() + + found = 0 + for j in events: + if j[u'EventName'] in target_events: + event = "cpu/event=%s,umask=%s/" % (j[u'EventCode'], j[u'UMask']) + if u'PEBS' in j and j[u'PEBS'] > 0: + event += "p" + if args.script: + eventmap[event].append(model) + else: + print j[u'EventName'], "event for model", model, "is", event + found += 1 + return found + +if not args.all: + cpu, model = get_cpu_str() + if not cpu: + sys.exit("Unknown CPU type") + +url = baseurl + "/mapfile.csv" +print >>sys.stderr, "Downloading", url +u = urllib2.urlopen(url) +found = 0 +cpufound = 0 +for j in u: + n = j.rstrip().split(',') + if len(n) >= 4 and (args.all or n[0] == cpu) and n[3] == "core": + if args.all: + vendor, fam, model = n[0].split("-") + model = int(model, 16) + cpufound += 1 + found += find_event(baseurl + n[2], model) +u.close() + +if args.script: + print '''#!/bin/sh +# Profile workload for gcc profile feedback (autofdo) using Linux perf. +# Auto generated. To regenerate for new CPUs run +# contrib/gen_autofdo_event.py --shell --all in gcc source + +# usages: +# gcc-auto-profile program (profile program and children) +# gcc-auto-profile -a sleep X (profile all for X secs, may need root) +# gcc-auto-profile -p PID sleep X (profile PID) +# gcc-auto-profile --kernel -a sleep X (profile kernel) +# gcc-auto-profile --all -a sleep X (profile kernel and user space) + +# Identify branches taken event for CPU. +# + +FLAGS=u + +if [ "$1" = "--kernel" ] ; then + FLAGS=k + shift +fi +if [ "$1" = "--all" ] ; then + FLAGS=uk + shift +fi + +if ! grep -q Intel /proc/cpuinfo ; then + echo >&2 "Only Intel CPUs supported" + exit 1 +fi + +if grep -q hypervisor /proc/cpuinfo ; then + echo >&2 "Warning: branch profiling may not be functional in VMs" +fi + +case `egrep -q "^cpu family\s*: 6" /proc/cpuinfo && + egrep "^model\s*:" /proc/cpuinfo | head -n1` in''' + for event, mod in eventmap.iteritems(): + for m in mod[:-1]: + print "model*:\ %s|\\" % m + print 'model*:\ %s) E="%s$FLAGS" ;;' % (mod[-1], event) + print '''*) +echo >&2 "Unknown CPU. Run contrib/gen_autofdo_event.py --all --script to update script." + exit 1 ;;''' + print "esac" + print 'exec perf record -e $E -b "$@"' + +if cpufound == 0 and not args.all: + sys.exit('CPU %s not found' % cpu) + +if found == 0: + sys.exit('Branch event not found') |