scripts/stackdelta

Source file repositories/reference/linux-study-clean/scripts/stackdelta

File Facts

System
Linux kernel
Corpus path
scripts/stackdelta
Extension
[no extension]
Size
1887 bytes
Lines
61
Domain
Support Tooling And Documentation
Bucket
scripts
Inferred role
Support Tooling And Documentation: scripts
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

while (<$fh>) {
	chomp;
	my ($file, $func, $size, $type) = split;
	# Old versions of gcc (at least 4.7) have an annoying quirk in
	# that a (static) function whose name has been changed into
	# for example ext4_find_unwritten_pgoff.isra.11 will show up
	# in the .su file with a name of just "11". Since such a
	# numeric suffix is likely to change across different
	# commits/compilers/.configs or whatever else we're trying to
	# tweak, we can't really track those functions, so we just
	# silently skip them.
	#
	# Newer gcc (at least 5.0) report the full name, so again,
	# since the suffix is likely to change, we strip it.
	next if $func =~ m/^[0-9]+$/;
	$func =~ s/\..*$//;
	# Line numbers are likely to change; strip those.
	$file =~ s/:[0-9]+$//;
	$su{"${file}\t${func}"} = {size => $size, type => $type};
    }
    close($fh);
    return \%su;
}

@ARGV == 2
    or die "usage: $0 <old> <new>";

my $old = read_stack_usage_file($ARGV[0]);
my $new = read_stack_usage_file($ARGV[1]);
my @common = sort grep {exists $new->{$_}} keys %$old;
for (@common) {
    my $x = $old->{$_}{size};
    my $y = $new->{$_}{size};
    my $delta = $y - $x;
    if ($delta) {
	printf "%s\t%d\t%d\t%+d\n", $_, $x, $y, $delta;
    }
}

Annotation

Implementation Notes