#!/usr/bin/perl -w
#
# hotuser - sample on-CPU user-level functions and libraries.
#           Written using Perl and DTrace (Solaris 10 03/05)
#
# This samples the on-CPU function at 1001 Hertz, for a simple yet
# effective user-level profiling tool for sampling exclusive function time.
# The output will identify which function is on the CPU the most - which
# is the hottest. See Notes/ALLexclusive_notes.txt for an explanation of
# exclusive time.
#
# $Id: hotuser,v 1.1.1.1 2015/09/30 22:01:06 christos Exp $
#
# USAGE:        hotuser [-hl] { -c command | -p PID }
#
#		-h              # help
#		-l              # match libraries, not functions
#		-p PID          # examine this PID
#		-c command      # run and examine this command
#       eg,
#		hotuser -p 81   # sample user functions from PID 81
#		hotuser -lp 81  # sample user libraries from PID 81
#		hotuser -p `pgrep -n Xorg`	# sample Xorg
#
# FIELDS:
#		FUNCTION        Function name
#		LIBRARY         Library name
#		COUNT           Number of samples
#		PCNT            Percentage of total samples
#
# COPYRIGHT: Copyright (c) 2006 Brendan Gregg.
#
# CDDL HEADER START
#
#  The contents of this file are subject to the terms of the
#  Common Development and Distribution License, Version 1.0 only
#  (the "License").  You may not use this file except in compliance
#  with the License.
#
#  You can obtain a copy of the license at Docs/cddl1.txt
#  or http://www.opensolaris.org/os/licensing.
#  See the License for the specific language governing permissions
#  and limitations under the License.
#
# CDDL HEADER END
#
# Author: Brendan Gregg  [Sydney, Australia]
#
# 29-Jun-2006	Brendan Gregg	Created this.
# 29-Jun-2006	   "      "	Last update.
#

use strict;
use Getopt::Std;

#
# Command Line Arguments
#
my $args;
usage() if defined $ARGV[0] and $ARGV[0] eq "--help";
getopts('c:hlp:') or usage();
usage() if defined $main::opt_h and $main::opt_h;
my $libs = defined $main::opt_l and $main::opt_l ? 1 : 0;
if (defined $main::opt_c) {
    $args = "-c $main::opt_c";
}
elsif (defined $main::opt_p) {
    $args = "-p $main::opt_p";
}
else {
    usage();
}

#
# Cleanup on signals
#
$SIG{INT} = \&cleanupsig;    # Ctrl-C
$SIG{QUIT} = \&cleanupsig;   # Ctrl-\
$SIG{TERM} = \&cleanupsig;   # TERM

#
# Declare DTrace script
#
my $dtrace = <<END;
/usr/sbin/dtrace -n '
	#pragma D option quiet
	profile:::profile-1001hz
	/pid == \$target/ 
	{
		\@pc[arg1] = count();
	}
	dtrace:::END
	{
		printa("OUT: %A %\@d\\n", \@pc);
	}
' '$args'
END

#
# Run DTrace, process output
#
my %Count;
my $total;
open DTRACE, "$dtrace |" or die "ERROR1: Can't run dtrace (perms?): $!\n";
print "Sampling... Hit Ctrl-C to end.\n";
while (my $line = <DTRACE>) {
    next if $line =~ /^\s*$/;
    next if $line !~ /^OUT: /;
    my ($tag, $addr, $count) = split ' ', $line;
    my ($name, $offset) = split /\+/, $addr;
    next if $name eq "0x0";
    $name =~ s/\`.*// if $libs;
    $Count{$name} += $count;
    $total += $count;
}
close DTRACE;

#
# Print final report
#
printf "\n%-52s %8s %6s\n", $libs ? "LIBRARY" : "FUNCTION", "COUNT", "PCNT";
foreach my $name (sort { $Count{$a} <=> $Count{$b} } keys %Count) {
    printf "%-52s %8d %5.1f%%\n", $name, $Count{$name},
                                  100 * $Count{$name} / ($total ? $total : 1);
}

#
# Subroutines
#
sub cleanupsig {
}
sub usage {
    print STDERR "USAGE: hotuser [-hl] { -c command | -p PID }\n";
    print STDERR "   eg,\n";
    print STDERR "       hotuser -p 81     # sample user funcs for PID 81\n";
    print STDERR "       hotuser -lp 81    # sample user libs for PID 81\n";
    print STDERR "       hotuser -p `pgrep -n Xorg`     # sample Xorg\n";
    exit 1;
}