[PATCH tip/core/rcu 10/18] torture: Make --kcsan argument also create a summary

[paulmck]

From: "Paul E. McKenney" <paulmck@xxxxxxxxxx>

The KCSAN tool emits a great many warnings for current kernels, for
example, a one-hour run of the full set of rcutorture scenarios results
in no fewer than 3252 such warnings, many of which are duplicates
or are otherwise closely related.  This commit therefore introduces
a kcsan-collapse.sh script that maps these warnings down to a set of
function pairs (22 of them given the 3252 individual warnings), placing
the resulting list in decreasing order of frequency of occurrence into
a kcsan.sum file.  If any KCSAN warnings were produced, the pathname of
this file is emitted at the end of the summary of the rcutorture runs.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
 .../selftests/rcutorture/bin/kcsan-collapse.sh     | 22 ++++++++++++++++++++++
 .../selftests/rcutorture/bin/kvm-recheck.sh        |  9 +++++++++
 tools/testing/selftests/rcutorture/bin/kvm.sh      |  1 +
 3 files changed, 32 insertions(+)
 create mode 100755 tools/testing/selftests/rcutorture/bin/kcsan-collapse.sh

diff --git a/tools/testing/selftests/rcutorture/bin/kcsan-collapse.sh b/tools/testing/selftests/rcutorture/bin/kcsan-collapse.sh
new file mode 100755
index 0000000..e5cc6b2
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/bin/kcsan-collapse.sh
@@ -0,0 +1,22 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# If this was a KCSAN run, collapse the reports in the various console.log
+# files onto pairs of functions.
+#
+# Usage: kcsan-collapse.sh resultsdir
+#
+# Copyright (C) 2020 Facebook, Inc.
+#
+# Authors: Paul E. McKenney <paulmck@xxxxxxxxxx>
+
+if test -z "$TORTURE_KCONFIG_KCSAN_ARG"
+then
+	exit 0
+fi
+cat $1/*/console.log |
+	grep "BUG: KCSAN: " |
+	sed -e 's/^\[[^]]*] //' |
+	sort |
+	uniq -c |
+	sort -k1nr > $1/kcsan.sum
diff --git a/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh b/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh
index 0326f4a..736f047 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm-recheck.sh
@@ -70,6 +70,15 @@ do
 			fi
 		fi
 	done
+	if test -f "$rd/kcsan.sum"
+	then
+		if test -s "$rd/kcsan.sum"
+		then
+			echo KCSAN summary in $rd/kcsan.sum
+		else
+			echo Clean KCSAN run in $rd
+		fi
+	fi
 done
 EDITOR=echo kvm-find-errors.sh "${@: -1}" > $T 2>&1
 ret=$?
diff --git a/tools/testing/selftests/rcutorture/bin/kvm.sh b/tools/testing/selftests/rcutorture/bin/kvm.sh
index 34b368d..75ae8e3 100755
--- a/tools/testing/selftests/rcutorture/bin/kvm.sh
+++ b/tools/testing/selftests/rcutorture/bin/kvm.sh
@@ -472,6 +472,7 @@ echo
 echo
 echo " --- `date` Test summary:"
 echo Results directory: $resdir/$ds
+kcsan-collapse.sh $resdir/$ds
 kvm-recheck.sh $resdir/$ds
 ___EOF___
 
-- 
2.9.5