kbuild: export-symbol usage report generator

#!/usr/bin/perl -w

#

# (C) Copyright IBM Corporation 2006.

#	Released under GPL v2.

#	Author : Ram Pai (linuxram@us.ibm.com)

#

# Usage: export_report.pl -k Module.symvers [-o report_file ] -f *.mod.c

#

use Getopt::Std;

use strict;

sub numerically {

	my $no1 = (split /\s+/, $a)[1];

	my $no2 = (split /\s+/, $b)[1];

	return $no1 <=> $no2;

}

sub alphabetically {

	my ($module1, $value1) = @{$a};

	my ($module2, $value2) = @{$b};

	return $value1 <=> $value2 || $module2 cmp $module1;

}

sub print_depends_on {

	my ($href) = @_;

	print "\n";

	while (my ($mod, $list) = each %$href) {

		print "\t$mod:\n";

		foreach my $sym (sort numerically @{$list}) {

			my ($symbol, $no) = split /\s+/, $sym;

			printf("\t\t%-25s\t%-25d\n", $symbol, $no);

		}

		print "\n";

	}

	print "\n";

	print "~"x80 , "\n";

}

sub usage {

        print "Usage: @_ -h -k Module.symvers  [ -o outputfile ] \n",

	      "\t-f: treat all the non-option argument as .mod.c files. ",

	      "Recommend using this as the last option\n",

	      "\t-h: print detailed help\n",

	      "\t-k: the path to Module.symvers file. By default uses ",

	      "the file from the current directory\n",

	      "\t-o outputfile: output the report to outputfile\n";

	exit 0;

}

sub collectcfiles {

        my @file = `cat .tmp_versions/*.mod | grep '.*\.ko\$'`;

        @file = grep {s/\.ko/.mod.c/} @file;

	chomp @file;

        return @file;

}

my (%SYMBOL, %MODULE, %opt, @allcfiles);

if (not getopts('hk:o:f',\%opt) or defined $opt{'h'}) {

        usage($0);

}

if (defined $opt{'f'}) {

	@allcfiles = @ARGV;

} else {

	@allcfiles = collectcfiles();

}

if (not defined $opt{'k'}) {

	$opt{'k'} = "Module.symvers";

}

unless (open(MODULE_SYMVERS, $opt{'k'})) {

	die "Sorry, cannot open $opt{'k'}: $!\n";

}

if (defined $opt{'o'}) {

	unless (open(OUTPUT_HANDLE, ">$opt{'o'}")) {

		die "Sorry, cannot open $opt{'o'} $!\n";

	}

	select OUTPUT_HANDLE;

}

#

# collect all the symbols and their attributes from the

# Module.symvers file

#

while ( <MODULE_SYMVERS> ) {

	chomp;

	my (undef, $symbol, $module, $gpl) = split;

	$SYMBOL { $symbol } =  [ $module , "0" , $symbol, $gpl];

}

close(MODULE_SYMVERS);

#

# collect the usage count of each symbol.

#

foreach my $thismod (@allcfiles) {

	unless (open(MODULE_MODULE, $thismod)) {

		print "Sorry, cannot open $thismod: $!\n";

		next;

	}

	my $state=0;

	while ( <MODULE_MODULE> ) {

		chomp;

		if ($state eq 0) {

			$state = 1 if ($_ =~ /static const struct modversion_info/);

			next;

		}

		if ($state eq 1) {

			$state = 2 if ($_ =~ /__attribute__\(\(section\("__versions"\)\)\)/);

			next;

		}

		if ($state eq 2) {

			if ( $_ !~ /0x[0-9a-f]{7,8},/ ) {

				next;

			}

			my $sym = (split /([,"])/,)[4];

			my ($module, $value, $symbol, $gpl) = @{$SYMBOL{$sym}};

			$SYMBOL{ $sym } =  [ $module, $value+1, $symbol, $gpl];

			push(@{$MODULE{$thismod}} , $sym);

		}

	}

	if ($state ne 2) {

		print "WARNING:$thismod is not built with CONFIG_MODVERSION enabled\n";

	}

	close(MODULE_MODULE);

}

print "\tThis file reports the exported symbols usage patterns by in-tree\n",

	"\t\t\t\tmodules\n";

printf("%s\n\n\n","x"x80);

printf("\t\t\t\tINDEX\n\n\n");

printf("SECTION 1: Usage counts of all exported symbols\n");

printf("SECTION 2: List of modules and the exported symbols they use\n");

printf("%s\n\n\n","x"x80);

printf("SECTION 1:\tThe exported symbols and their usage count\n\n");

printf("%-25s\t%-25s\t%-5s\t%-25s\n", "Symbol", "Module", "Usage count",

	"export type");

#

# print the list of unused exported symbols

#

foreach my $list (sort alphabetically values(%SYMBOL)) {

	my ($module, $value, $symbol, $gpl) = @{$list};

	printf("%-25s\t%-25s\t%-10s\t", $symbol, $module, $value);

	if (defined $gpl) {

		printf("%-25s\n",$gpl);

	} else {

		printf("\n");

	}

}

printf("%s\n\n\n","x"x80);

printf("SECTION 2:\n\tThis section reports export-symbol-usage of in-kernel

modules. Each module lists the modules, and the symbols from that module that

it uses.  Each listed symbol reports the number of modules using it\n");

print "~"x80 , "\n";

while (my ($thismod, $list) = each %MODULE) {

	my %depends;

	$thismod =~ s/\.mod\.c/.ko/;

	print "\t\t\t$thismod\n";

	foreach my $symbol (@{$list}) {

		my ($module, $value, undef, $gpl) = @{$SYMBOL{$symbol}};

		push (@{$depends{"$module"}}, "$symbol $value");

	}

	print_depends_on(\%depends);

}