check: check dmesg log after each test

Check kernel BUG, WARNING etc. in dmesg log after each test and fail the
test if something is found. dmesg log can be found at result dir.

This check now depends on the logging of running tests in dmesg, so this
check can be done without clearing dmesg buffer nor dumping all dmesg to
a file, which can potentially eat all free space on testing host.

Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

check

@@ -397,6 +397,32 @@ _check_filesystems()
 	fi
 }
 
+_check_dmesg()
+{
+	if [ ! -f ${RESULT_DIR}/check_dmesg ]; then
+		return
+	fi
+	rm -f ${RESULT_DIR}/check_dmesg
+
+	# search the dmesg log of last run of $seqnum for possible failures
+	# use sed \cregexpc address type, since $seqnum contains "/"
+	dmesg | tac | sed -ne "0,\#run fstests $seqnum at $date_time#p" | \
+		tac >$seqres.dmesg
+	grep -q -e "kernel BUG at" \
+	     -e "WARNING:" \
+	     -e "BUG:" \
+	     -e "Oops:" \
+	     -e "possible recursive locking detected" \
+	     $seqres.dmesg
+	if [ $? -eq 0 ]; then
+		echo "_check_dmesg: something found in dmesg (see $seqres.dmesg)"
+		err=true
+	else
+		rm -f $seqres.dmesg
+	fi
+}
+
+
 _prepare_test_list
 
 if $OPTIONS_HAVE_SECTIONS; then
@@ -564,6 +590,8 @@ for section in $HOST_OPTIONS_SECTIONS; do
 		if [ -w /dev/kmsg ]; then
 			date_time=`date +"%F %T"`
 			echo "run fstests $seqnum at $date_time" > /dev/kmsg
+			# _check_dmesg depends on this log in dmesg
+			touch ${RESULT_DIR}/check_dmesg
 		fi
 		./$seq >$tmp.rawout 2>&1
 		sts=$?
@@ -630,6 +658,7 @@ for section in $HOST_OPTIONS_SECTIONS; do
 		    try="$try $seqnum"
 		    n_try=`expr $n_try + 1`
 		    _check_filesystems
+		    _check_dmesg
 		fi
 
 	    fi