1#!/usr/bin/python 2# Generate Intel taken branches Linux perf event script for autofdo profiling. 3 4# Copyright (C) 2016 Free Software Foundation, Inc. 5# 6# GCC is free software; you can redistribute it and/or modify it under 7# the terms of the GNU General Public License as published by the Free 8# Software Foundation; either version 3, or (at your option) any later 9# version. 10# 11# GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12# WARRANTY; without even the implied warranty of MERCHANTABILITY or 13# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14# for more details. 15# 16# You should have received a copy of the GNU General Public License 17# along with GCC; see the file COPYING3. If not see 18# <http://www.gnu.org/licenses/>. */ 19 20# Run it with perf record -b -e EVENT program ... 21# The Linux Kernel needs to support the PMU of the current CPU, and 22# It will likely not work in VMs. 23# Add --all to print for all cpus, otherwise for current cpu. 24# Add --script to generate shell script to run correct event. 25# 26# Requires internet (https) access. This may require setting up a proxy 27# with export https_proxy=... 28# 29import urllib2 30import sys 31import json 32import argparse 33import collections 34 35baseurl = "https://download.01.org/perfmon" 36 37target_events = (u'BR_INST_RETIRED.NEAR_TAKEN', 38 u'BR_INST_EXEC.TAKEN', 39 u'BR_INST_RETIRED.TAKEN_JCC', 40 u'BR_INST_TYPE_RETIRED.COND_TAKEN') 41 42ap = argparse.ArgumentParser() 43ap.add_argument('--all', '-a', help='Print for all CPUs', action='store_true') 44ap.add_argument('--script', help='Generate shell script', action='store_true') 45args = ap.parse_args() 46 47eventmap = collections.defaultdict(list) 48 49def get_cpu_str(): 50 with open('/proc/cpuinfo', 'r') as c: 51 vendor, fam, model = None, None, None 52 for j in c: 53 n = j.split() 54 if n[0] == 'vendor_id': 55 vendor = n[2] 56 elif n[0] == 'model' and n[1] == ':': 57 model = int(n[2]) 58 elif n[0] == 'cpu' and n[1] == 'family': 59 fam = int(n[3]) 60 if vendor and fam and model: 61 return "%s-%d-%X" % (vendor, fam, model), model 62 return None, None 63 64def find_event(eventurl, model): 65 print >>sys.stderr, "Downloading", eventurl 66 u = urllib2.urlopen(eventurl) 67 events = json.loads(u.read()) 68 u.close() 69 70 found = 0 71 for j in events: 72 if j[u'EventName'] in target_events: 73 event = "cpu/event=%s,umask=%s/" % (j[u'EventCode'], j[u'UMask']) 74 if u'PEBS' in j and j[u'PEBS'] > 0: 75 event += "p" 76 if args.script: 77 eventmap[event].append(model) 78 else: 79 print j[u'EventName'], "event for model", model, "is", event 80 found += 1 81 return found 82 83if not args.all: 84 cpu, model = get_cpu_str() 85 if not cpu: 86 sys.exit("Unknown CPU type") 87 88url = baseurl + "/mapfile.csv" 89print >>sys.stderr, "Downloading", url 90u = urllib2.urlopen(url) 91found = 0 92cpufound = 0 93for j in u: 94 n = j.rstrip().split(',') 95 if len(n) >= 4 and (args.all or n[0] == cpu) and n[3] == "core": 96 if args.all: 97 vendor, fam, model = n[0].split("-") 98 model = int(model, 16) 99 cpufound += 1 100 found += find_event(baseurl + n[2], model) 101u.close() 102 103if args.script: 104 print '''#!/bin/sh 105# Profile workload for gcc profile feedback (autofdo) using Linux perf. 106# Auto generated. To regenerate for new CPUs run 107# contrib/gen_autofdo_event.py --script --all in gcc source 108 109# usages: 110# gcc-auto-profile program (profile program and children) 111# gcc-auto-profile -a sleep X (profile all for X secs, may need root) 112# gcc-auto-profile -p PID sleep X (profile PID) 113# gcc-auto-profile --kernel -a sleep X (profile kernel) 114# gcc-auto-profile --all -a sleep X (profile kernel and user space) 115 116# Identify branches taken event for CPU. 117# 118 119FLAGS=u 120 121if [ "$1" = "--kernel" ] ; then 122 FLAGS=k 123 shift 124fi 125if [ "$1" = "--all" ] ; then 126 FLAGS=uk 127 shift 128fi 129 130if ! grep -q Intel /proc/cpuinfo ; then 131 echo >&2 "Only Intel CPUs supported" 132 exit 1 133fi 134 135if grep -q hypervisor /proc/cpuinfo ; then 136 echo >&2 "Warning: branch profiling may not be functional in VMs" 137fi 138 139case `egrep -q "^cpu family\s*: 6" /proc/cpuinfo && 140 egrep "^model\s*:" /proc/cpuinfo | head -n1` in''' 141 for event, mod in eventmap.iteritems(): 142 for m in mod[:-1]: 143 print "model*:\ %s|\\" % m 144 print 'model*:\ %s) E="%s$FLAGS" ;;' % (mod[-1], event) 145 print '''*) 146echo >&2 "Unknown CPU. Run contrib/gen_autofdo_event.py --all --script to update script." 147 exit 1 ;;''' 148 print "esac" 149 print 'exec perf record -e $E -b "$@"' 150 151if cpufound == 0 and not args.all: 152 sys.exit('CPU %s not found' % cpu) 153 154if found == 0: 155 sys.exit('Branch event not found') 156