The Tor Browser: tools/trace-malloc/diffbloatdump.pl@97036ab72558 (annotated)

tools/trace-malloc/diffbloatdump.pl@97036ab72558 (annotated)

tools/trace-malloc/diffbloatdump.pl

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rwxr-xr-x

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 #!/usr/bin/perl -w
 # vim:cindent:ts=8:et:sw=4:
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 # This script produces a diff between two files that are the result of
 # calling NS_TraceMallocDumpAllocations.  Such files can be created
 # through the command-line option --shutdown-leaks=<filename> or through
 # the DOM function window.TraceMallocDumpAllocations(<filename>).  Both
 # methods will work only if --trace-malloc=<malloc-log> is also given on
 # the command line.
 use 5.004;
 use strict;
 use Getopt::Long;
 $::opt_help = 0;
 $::opt_depth = 6;
 $::opt_include_zero = 0;
 $::opt_allocation_count = 0;
 $::opt_use_address = 0;
 # XXX Change --use-address to be the default and remove the option
 # once tinderbox is no longer using it without --use-address.
 Getopt::Long::Configure("pass_through");
 Getopt::Long::GetOptions("help", "allocation-count", "depth=i",
                          "include-zero", "use-address");
 if ($::opt_help) {
     die "usage: diffbloatdump.pl [options] <dump1> <dump2>
   --help                 Display this message
   --allocation-count     Use allocation count rather than size (i.e., treat
                            all sizes as 1).
   --depth=<num>          Only display <num> frames at top of allocation stack.
   --include-zero         Display subtrees totalling zero.
   --use-address          Don't ignore the address part of the stack trace
                            (can make comparison more accurate when comparing
                            results from the same build)
   The input files (<dump1> and <dump2> above) are either trace-malloc
   memory dumps OR this script's output.  (If this script's output,
   --allocation-count and --use-address are ignored.)  If the input files
   have .gz or .bz2 extension, they are uncompressed.
 ";
 }
 my $calltree = { count => 0 }; # leave children undefined
 sub get_child($$) {
     my ($node, $frame) = @_;
     if (!defined($node->{children})) {
         $node->{children} = {};
     }
     if (!defined($node->{children}->{$frame})) {
         $node->{children}->{$frame} = { count => 0 };
     }
     return $node->{children}->{$frame};
 }
 sub add_tree_file($$$) {
     my ($infile, $firstline, $factor) = @_;
     my @nodestack;
     $nodestack[1] = $calltree;
     $firstline =~ /^(-?\d+) malloc$/;
     $calltree->{count} += $1 * $factor;
     my $lineno = 1;
     while (!eof($infile)) {
         my $line = <$infile>;
         ++$lineno;
         $line =~ /^( *)(-?\d+) (.*)$/ || die "malformed input, line $lineno";
         my $depth = length($1);
         my $count = $2;
         my $frame = $3;
         die "malformed input, line $lineno" if ($depth % 2 != 0);
         $depth /= 2;
         die "malformed input, line $lineno" if ($depth > $#nodestack);
         $#nodestack = $depth;
         my $node = get_child($nodestack[$depth], $frame);
         push @nodestack, $node;
         $node->{count} += $count * $factor;
     }
 }
 sub add_file($$) {
     # Takes (1) a reference to a file descriptor for input and (2) the
     # factor to multiply the stacks by (generally +1 or -1).
     # Returns a reference to an array representing the stack, allocation
     # site in array[0].
     sub read_stack($) {
         my ($infile) = @_;
         my $line;
         my @stack;
         # read the data at the memory location
         while ( defined($infile) && ($line = <$infile>) && substr($line,0,1) eq "\t" ) {
             # do nothing
         }
         # read the stack
         do {
             chomp($line);
             if ( ! $::opt_use_address &&
                  $line =~ /(.*)\[(.*)\]/) {
                 $line = $1;
             }
             $stack[$#stack+1] = $line;
         } while ( defined($infile) && ($line = <$infile>) && $line ne "\n" && $line ne "\r\n" );
         return \@stack;
     }
     # adds the stack given as a parameter (reference to array, $stack[0] is
     # allocator) to $calltree, with the call count multiplied by $factor
     # (typically +1 or -1).
     sub add_stack($$) {
         my @stack = @{$_[0]};
         my $factor = $_[1];
         my $i = 0;
         my $node = $calltree;
         while ($i < $#stack && $i < $::opt_depth) {
             $node->{count} += $factor;
             $node = get_child($node, $stack[$i]);
             ++$i;
         }
         $node->{count} += $factor;
     }
     my ($infile, $factor) = @_;
     if ($infile =~ /\.bz2$/) {
         # XXX This doesn't propagate errors from bzip2.
         open (INFILE, "bzip2 -cd '$infile' |") || die "Can't open input \"$infile\"";
     } elsif ($infile =~ /\.gz$/) {
         # XXX This doesn't propagate errors from gzip.
         open (INFILE, "gzip -cd '$infile' |") || die "Can't open input \"$infile\"";
     } else {
         open (INFILE, "<$infile") || die "Can't open input \"$infile\"";
     }
     my $first = 1;
     while ( ! eof(INFILE) ) {
         # read the type and address
         my $line = <INFILE>;
         if ($first) {
             $first = 0;
             if ($line =~ /^-?\d+ malloc$/) {
                 # We're capable of reading in our own output as well.
                 add_tree_file(\*INFILE, $line, $factor);
                 close INFILE;
                 return;
             }
         }
         unless ($line =~ /.*\((\d*)\)[\r|\n]/) {
             die "badly formed allocation header in $infile";
         }
         my $size;
         if ($::opt_allocation_count) {
             $size = 1;
         } else {
             $size = $1;
         }
         add_stack(read_stack(\*INFILE), $size * $factor);
     }
     close INFILE;
 }
 sub print_node_indent($$$);
 sub print_calltree() {
     sub print_indent($) {
         my ($i) = @_;
         while (--$i >= 0) {
             print "  ";
         }
     }
     sub print_node_indent($$$) {
         my ($nodename, $node, $indent) = @_;
         if (!$::opt_include_zero && $node->{count} == 0) {
             return;
         }
         print_indent($indent);
         print "$node->{count} $nodename\n";
         if (defined($node->{children})) {
             my %kids = %{$node->{children}};
             ++$indent;
             foreach my $kid (sort { $kids{$b}->{count} <=> $kids{$a}->{count} }
                                   keys (%kids)) {
                 print_node_indent($kid, $kids{$kid}, $indent);
             }
         }
     }
     print_node_indent("malloc", $calltree, 0);
 }
 add_file($ARGV[0], -1);
 add_file($ARGV[1],  1);
 print_calltree();

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tools/trace-malloc/diffbloatdump.pl@97036ab72558 (annotated)

tools/trace-malloc/diffbloatdump.pl