--- /dev/null
+#!/bin/bash
+#
+# Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com>
+#
+# SPDX-License-Identifier: LGPL-2.1-only
+
+CURDIR=$(dirname "$0")/
+TESTDIR=$CURDIR/../../../
+
+TMPDIR=$(mktemp -d)
+
+TESTAPP_PATH="$TESTDIR/utils/testapp"
+TESTAPP_NAME="gen-ust-events"
+TESTAPP_BIN="$TESTAPP_PATH/$TESTAPP_NAME/$TESTAPP_NAME"
+
+TESTPOINT_BASE_PATH=$(readlink -f "$TMPDIR/lttng.t_p_n")
+TESTPOINT_PIPE_PATH=$(mktemp -u "${TESTPOINT_BASE_PATH}.XXXXXX")
+TESTPOINT=$(readlink -f "${CURDIR}/.libs/libpause_sessiond.so")
+
+SH_TAP=1
+
+# shellcheck source=../../../utils/utils.sh
+source "$TESTDIR/utils/utils.sh"
+# shellcheck source=./util_event_generator.sh
+source "$CURDIR/util_event_generator.sh"
+
+FULL_LTTNG_BIN="${TESTDIR}/../src/bin/lttng/${LTTNG_BIN}"
+FULL_LTTNG_SESSIOND_BIN="${TESTDIR}/../src/bin/lttng-sessiond/lttng-sessiond"
+
+UST_NUM_TESTS=16
+KERNEL_NUM_TESTS=15
+NUM_TESTS=$(($UST_NUM_TESTS + $KERNEL_NUM_TESTS))
+
+plan_tests $NUM_TESTS
+
+function test_kernel_notifier_discarded_count
+{
+ local sessiond_pipe=()
+ local trigger_name="my_trigger"
+ local list_triggers_stdout=$(mktemp -t list_triggers_stdout.XXXXXX)
+
+ # Used on sessiond launch.
+ LTTNG_SESSIOND_ENV_VARS="LTTNG_TESTPOINT_ENABLE=1 \
+ NOTIFIER_PAUSE_PIPE_PATH=${TESTPOINT_PIPE_PATH} \
+ LD_PRELOAD=${TESTPOINT}"
+
+ diag "Kernel event notifer error counter"
+
+ start_lttng_sessiond_notap
+
+ # This is needed since the testpoint create a pipe with the sessiond
+ # type suffixed.
+ for f in "$TESTPOINT_BASE_PATH"*; do
+ sessiond_pipe+=("$f")
+ done
+
+ lttng_add_trigger_ok "$trigger_name" \
+ --condition on-event --kernel lttng_test_filter_event \
+ --action notify
+
+ "$FULL_LTTNG_BIN" list-triggers > "$list_triggers_stdout"
+
+ # Confirm that the discarded notification line is present.
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded: 0"
+ ok $? "No discarded tracer notification"
+
+ # Stop consumption of notifier tracer notifications.
+ echo -n 1 > $sessiond_pipe
+
+ # The notifier ring buffer configuration is currently made of 16 4096
+ # bytes subbuffers. Each kernel notification is at least 42 bytes long.
+ # To fill it, we need to generate (16 * 4096)/42 = 1561 notifications.
+ # That number is a bit larger than what we need since some of the space
+ # is lost in subbuffer boundaries.
+ echo -n "200000" > /proc/lttng-test-filter-event
+
+ "$FULL_LTTNG_BIN" list-triggers > "$list_triggers_stdout"
+
+ # Confirm that the discarded notification line is present. To avoid
+ # false positive.
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded"
+ ok $? "Tracer notification discarded line printed"
+
+ # Confirm that the number of tracer notifications discarded is not zero.
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded: 0"
+ isnt $? 0 "Discarded tracer notification number non-zero as expected"
+
+ lttng_remove_trigger_ok "$trigger_name"
+
+ # Confirm that no notifier is enabled.
+ list_triggers_line_count=$("$FULL_LTTNG_BIN" list-triggers | wc -l)
+ is "$list_triggers_line_count" "0" "No \`on-event\` kernel notifier enabled as expected"
+
+ # Enable another notifier and list it to confirm the counter was cleared.
+ lttng_add_trigger_ok "$trigger_name" \
+ --condition on-event --kernel lttng_test_filter_event \
+ --action notify
+
+ # Confirm that the discarded notification line is present.
+ "$FULL_LTTNG_BIN" list-triggers > "$list_triggers_stdout"
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded: 0"
+ ok $? "No discarded tracer notification"
+
+ lttng_remove_trigger_ok "$trigger_name"
+
+ stop_lttng_sessiond_notap
+
+ unset LTTNG_SESSIOND_ENV_VARS
+
+ rm -f "$list_triggers_stdout"
+}
+
+function test_kernel_notifier_discarded_count_max_bucket
+{
+ start_lttng_sessiond "" "--event-notifier-error-number-of-bucket=3"
+
+ diag "Kernel event notifer error counter bucket limit"
+ for i in $(seq 3); do
+ lttng_add_trigger_ok "$i" \
+ --condition on-event --kernel my_event_that_doesnt_need_to_really_exist_$i \
+ --action notify
+ done
+
+ for i in $(seq 4 5); do
+ lttng_add_trigger_fail "$i" \
+ --condition on-event --kernel my_event_that_doesnt_need_to_really_exist_$i \
+ --action notify
+ done
+
+ stop_lttng_sessiond_notap
+}
+
+function test_ust_notifier_discarded_count
+{
+ local sessiond_pipe=()
+ local trigger_name="my_trigger"
+ local list_triggers_stdout=$(mktemp -t list_triggers_stdout.XXXXXX)
+ local NR_ITER=2000
+ local NR_USEC_WAIT=0
+
+
+ diag "UST event notifer error counter"
+ # Used on sessiond launch.
+ LTTNG_SESSIOND_ENV_VARS="LTTNG_TESTPOINT_ENABLE=1 \
+ NOTIFIER_PAUSE_PIPE_PATH=${TESTPOINT_PIPE_PATH} \
+ LD_PRELOAD=${TESTPOINT}"
+
+ start_lttng_sessiond_notap
+
+ # This is needed since the testpoint create a pipe with the sessiond
+ # type suffixed.
+ for f in "$TESTPOINT_BASE_PATH"*; do
+ sessiond_pipe+=("$f")
+ done
+
+ lttng_add_trigger_ok "$trigger_name" \
+ --condition on-event --userspace tp:tptest \
+ --action notify
+
+ "$FULL_LTTNG_BIN" list-triggers > "$list_triggers_stdout"
+
+ # Confirm that the discarded notification line is present.
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded: 0"
+ ok $? "No discarded tracer notification"
+
+ # Stop consumption of notifier tracer notifications.
+ echo -n 1 > $sessiond_pipe
+
+ # The notifier ring buffer configuration is currently made of 16 4096
+ # bytes subbuffers. Each userspace notification is at least 42 bytes long.
+ # To fill it, we need to generate (16 * 4096)/42 = 1561 notifications.
+ # That number is a bit larger than what we need since some of the space
+ # is lost in subbuffer boundaries.
+ $TESTAPP_BIN -i $NR_ITER -w $NR_USEC_WAIT
+ ok $? "Generating $NR_ITER tracer notifications"
+
+ "$FULL_LTTNG_BIN" list-triggers > "$list_triggers_stdout"
+
+ # Confirm that the discarded notification line is present. To avoid
+ # false positive.
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded"
+ ok $? "Tracer notification discarded line printed"
+
+ # Confirm that the number of tracer notifications discarded is not zero.
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded: 0"
+ isnt $? 0 "Discarded tracer notification number non-zero as expected"
+
+ # Remove the notifier.
+ lttng_remove_trigger_ok "$trigger_name"
+
+ # Confirm that no notifier is enabled.
+ list_triggers_line_count=$("$FULL_LTTNG_BIN" list-triggers | wc -l)
+ is "$list_triggers_line_count" "0" "No \`on-event\` userspace notifier enabled as expected"
+
+ # Enable another notifier and list it to confirm the counter was cleared.
+ lttng_add_trigger_ok "$trigger_name" \
+ --condition on-event --userspace tp:tptest \
+ --action notify
+
+ # Confirm that the discarded notification line is present.
+ "$FULL_LTTNG_BIN" list-triggers > "$list_triggers_stdout"
+ cat "$list_triggers_stdout" | grep --quiet "tracer notifications discarded: 0"
+ ok $? "No discarded tracer notification"
+
+ lttng_remove_trigger_ok "$trigger_name"
+
+ stop_lttng_sessiond_notap
+
+ unset LTTNG_SESSIOND_ENV_VARS
+
+ rm -f "$list_triggers_stdout"
+}
+function test_ust_notifier_discarded_count_max_bucket
+{
+ start_lttng_sessiond "" "--event-notifier-error-number-of-bucket=3"
+
+ diag "UST event notifer error counter bucket limit"
+ for i in $(seq 3); do
+ lttng_add_trigger_ok "$i" \
+ --condition on-event --userspace my_event_that_doesnt_need_to_really_exist_$i \
+ --action notify
+ done
+
+ for i in $(seq 4 5); do
+ lttng_add_trigger_fail "$i" \
+ --condition on-event --userspace my_event_that_doesnt_need_to_really_exist_$i \
+ --action notify
+ done
+
+ stop_lttng_sessiond_notap
+}
+
+test_ust_notifier_discarded_count
+test_ust_notifier_discarded_count_max_bucket
+
+if [ "$(id -u)" == "0" ]; then
+
+ validate_lttng_modules_present
+
+ modprobe lttng-test
+
+ test_kernel_notifier_discarded_count
+
+ test_kernel_notifier_discarded_count_max_bucket
+
+ modprobe --remove lttng-test
+
+ rm -rf "${sessiond_pipe[@]}" 2> /dev/null
+else
+ # Kernel tests are skipped.
+ skip 0 "Root access is needed. Skipping all kernel notification tests." $KERNEL_NUM_TESTS
+fi
+
+rm -rf "$TMPDIR"