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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/scripts/stackdelta
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/scripts/stackdelta')
-rwxr-xr-xkernel/scripts/stackdelta59
1 files changed, 59 insertions, 0 deletions
diff --git a/kernel/scripts/stackdelta b/kernel/scripts/stackdelta
new file mode 100755
index 000000000..48eabf2f4
--- /dev/null
+++ b/kernel/scripts/stackdelta
@@ -0,0 +1,59 @@
+#!/usr/bin/perl
+
+# Read two files produced by the stackusage script, and show the
+# delta between them.
+#
+# Currently, only shows changes for functions listed in both files. We
+# could add an option to show also functions which have vanished or
+# appeared (which would often be due to gcc making other inlining
+# decisions).
+#
+# Another possible option would be a minimum absolute value for the
+# delta.
+#
+# A third possibility is for sorting by delta, but that can be
+# achieved by piping to sort -k5,5g.
+
+sub read_stack_usage_file {
+ my %su;
+ my $f = shift;
+ open(my $fh, '<', $f)
+ or die "cannot open $f: $!";
+ while (<$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;
+ }
+}