[RFC PATCH 19/20] tools/rv: Add selftest for rv bpf

[Gabriele Monaco <gmonaco@redhat.com>]

Add selftest cases for the rv userspace tool BPF commands and monitors,
test BPF monitors registration, unregistration and functionality,
including traces and reactors.

Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
---
 tools/verification/rv/tests/rv_bpf.t | 104 +++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 tools/verification/rv/tests/rv_bpf.t

diff --git a/tools/verification/rv/tests/rv_bpf.t b/tools/verification/rv/tests/rv_bpf.t
new file mode 100644
index 000000000000..902343f0d3f1
--- /dev/null
+++ b/tools/verification/rv/tests/rv_bpf.t
@@ -0,0 +1,104 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+source ../tests/engine.sh
+test_begin
+
+set_timeout 30s
+
+RVDIR=/sys/kernel/tracing/rv
+
+check "verify bpf subcommand help" \
+	"$RV bpf --help" 0 "manage BPF monitor registration"
+
+if $RV bpf unregister 2>&1 | grep -q "kernel does not support BPF monitors"; then
+	test_end
+	exit 0
+fi
+
+if ! mount | grep -q /sys/fs/bpf; then
+	mount -t bpf bpf /sys/fs/bpf
+fi
+
+check "nohz does not exist before register" \
+	"$RV mon nohz" 1 "monitor nohz does not exist"
+
+check "tqueue does not exist before register" \
+	"$RV mon tqueue" 1 "monitor tqueue does not exist"
+
+check "register BPF monitors" \
+	"$RV bpf register" 0 "registered [0-9]\+ BPF monitor(s)"
+
+set_expected_timeout 2s
+
+header="^[[:space:]]\+\(\([][A-Z_x<>-]\+\||\)[[:space:]]*\)\+$"
+type="\(event\|error\)[[:space:]]\+"
+genpid="[0-9]\+[[:space:]]\+"
+selfpid="\$pid[[:space:]]\+"
+cpu="\[[0-9]\{3\}\][[:space:]]\+"
+state="[a-z_]\+ "
+trace_task="${genpid}${cpu}${type}${genpid}${state}"
+trace_task_self="${genpid}${cpu}${type}${selfpid}${state}"
+trace_cpu="${genpid}${cpu}${type}${state}"
+trace_cpu_self="${selfpid}${cpu}${type}${state}"
+
+check_if_exists "run a BPF monitor without parameters" \
+	"$RV mon nohz" "$RVDIR/monitors/nohz" "" "."
+
+check_if_exists "run a per-task BPF monitor without parameters" \
+	"$RV mon tqueue" "$RVDIR/monitors/tqueue" "" "."
+
+check_if_exists "run per-task BPF monitor with tracing" \
+	"$RV mon tqueue -t" "$RVDIR/monitors/tqueue" \
+	"$header" "$trace_task_self" "\($header\|$trace_task\)"
+
+check_if_exists "run per-task BPF monitor tracing also self" \
+	"$RV mon tqueue -t -s" "$RVDIR/monitors/tqueue" \
+	"$trace_task_self" "" "\($header\|$trace_task\)"
+
+check_if_exists "run per-cpu BPF monitor with tracing" \
+	"$RV mon nohz -t" "$RVDIR/monitors/nohz" \
+	"$header" "$trace_cpu_self" "\($header\|$trace_cpu\)"
+
+# This is unstable, we may never see events from self
+#check_if_exists "run per-cpu BPF monitor tracing also self" \
+#	"$RV mon nohz -t -s" "$RVDIR/monitors/nohz" \
+#	"$trace_cpu_self" "" "\($header\|$trace_cpu\)"
+
+lines_before=$(($(dmesg | wc -l) + 1))
+check_if_exists "run a BPF monitor with a reactor" \
+	"$RV mon nohz -r printk && dmesg | tail -n +$lines_before" "$RVDIR/monitors/nohz" \
+	"rv: monitor nohz does not allow event"
+
+set_timeout 30s
+
+check "already enabled monitor returns error" \
+	"echo 1 > $RVDIR/monitors/nohz/enable; $RV mon nohz" 1 \
+	"monitor nohz (BPF) is already enabled"
+[ -n "$TEST_COUNT" ] && echo 0 > $RVDIR/monitors/nohz/enable
+
+check "already enabled monitor prevents unregistration" \
+	"echo 1 > $RVDIR/monitors/nohz/enable; $RV bpf unregister" 1 \
+	"monitor nohz is enabled, cannot unregister" \
+	"unregistered [0-9]\+ BPF monitor(s)"
+[ -n "$TEST_COUNT" ] && echo 0 > $RVDIR/monitors/nohz/enable
+
+check "unregister BPF monitors" \
+	"$RV bpf unregister" 0 "unregistered [0-9]\+ BPF monitor(s)"
+
+check "nohz does not exist after unregister" \
+	"$RV mon nohz" 1 "monitor nohz does not exist"
+
+check "tqueue does not exist after unregister" \
+	"$RV mon tqueue" 1 "monitor tqueue does not exist"
+
+check "nothing left to unregister" \
+	"$RV bpf unregister" 0 "unregistered 0 BPF monitor(s)"
+
+# Error handling tests
+check "bpf without subcommand" \
+	"$RV bpf" 1 "usage: rv bpf"
+
+check "invalid bpf subcommand" \
+	"$RV bpf invalid" 1 "usage: rv bpf"
+
+test_end
-- 
2.55.0