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authorDapeng Mi <dapeng1.mi@linux.intel.com>2026-09-17 09:52:33 +0800
committerIngo Molnar <mingo@kernel.org>2026-09-22 11:37:46 +0200
commit0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch)
tree531306c2299f9a269f0a986e29f17ba972180104 /scripts/stackdelta
downloadlinux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz
linux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.zip
perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
Diffstat (limited to 'scripts/stackdelta')
-rwxr-xr-xscripts/stackdelta60
1 files changed, 60 insertions, 0 deletions
diff --git a/scripts/stackdelta b/scripts/stackdelta
new file mode 100755
index 000000000..44d2dfd62
--- /dev/null
+++ b/scripts/stackdelta
@@ -0,0 +1,60 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+
+# 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;
+ }
+}