4 files changed, 175 insertions, 0 deletions
diff --git a/kernel/trace/rv/monitors/snep/Kconfig b/kernel/trace/rv/monitors/snep/Kconfig
new file mode 100644
index 000000000000..77527f971232
--- /dev/null
+++ b/kernel/trace/rv/monitors/snep/Kconfig
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+config RV_MON_SNEP
+	depends on RV
+	depends on PREEMPT_TRACER
+	depends on RV_MON_SCHED
+	default y
+	select DA_MON_EVENTS_IMPLICIT
+	bool "snep monitor"
+	help
+	  Monitor to ensure schedule does not enable preempt.
+	  This monitor is part of the sched monitors collection.
+
+	  For further information, see:
+	    Documentation/trace/rv/monitor_sched.rst
diff --git a/kernel/trace/rv/monitors/snep/snep.c b/kernel/trace/rv/monitors/snep/snep.c
new file mode 100644
index 000000000000..0076ba6d7ea4
--- /dev/null
+++ b/kernel/trace/rv/monitors/snep/snep.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/ftrace.h>
+#include <linux/tracepoint.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rv.h>
+#include <rv/instrumentation.h>
+#include <rv/da_monitor.h>
+
+#define MODULE_NAME "snep"
+
+#include <trace/events/sched.h>
+#include <trace/events/preemptirq.h>
+#include <rv_trace.h>
+#include <monitors/sched/sched.h>
+
+#include "snep.h"
+
+static struct rv_monitor rv_snep;
+DECLARE_DA_MON_PER_CPU(snep, unsigned char);
+
+static void handle_preempt_disable(void *data, unsigned long ip, unsigned long parent_ip)
+{
+	da_handle_start_event_snep(preempt_disable_snep);
+}
+
+static void handle_preempt_enable(void *data, unsigned long ip, unsigned long parent_ip)
+{
+	da_handle_start_event_snep(preempt_enable_snep);
+}
+
+static void handle_schedule_entry(void *data, bool preempt, unsigned long ip)
+{
+	da_handle_event_snep(schedule_entry_snep);
+}
+
+static void handle_schedule_exit(void *data, bool is_switch, unsigned long ip)
+{
+	da_handle_start_event_snep(schedule_exit_snep);
+}
+
+static int enable_snep(void)
+{
+	int retval;
+
+	retval = da_monitor_init_snep();
+	if (retval)
+		return retval;
+
+	rv_attach_trace_probe("snep", preempt_disable, handle_preempt_disable);
+	rv_attach_trace_probe("snep", preempt_enable, handle_preempt_enable);
+	rv_attach_trace_probe("snep", sched_entry_tp, handle_schedule_entry);
+	rv_attach_trace_probe("snep", sched_exit_tp, handle_schedule_exit);
+
+	return 0;
+}
+
+static void disable_snep(void)
+{
+	rv_snep.enabled = 0;
+
+	rv_detach_trace_probe("snep", preempt_disable, handle_preempt_disable);
+	rv_detach_trace_probe("snep", preempt_enable, handle_preempt_enable);
+	rv_detach_trace_probe("snep", sched_entry_tp, handle_schedule_entry);
+	rv_detach_trace_probe("snep", sched_exit_tp, handle_schedule_exit);
+
+	da_monitor_destroy_snep();
+}
+
+static struct rv_monitor rv_snep = {
+	.name = "snep",
+	.description = "schedule does not enable preempt.",
+	.enable = enable_snep,
+	.disable = disable_snep,
+	.reset = da_monitor_reset_all_snep,
+	.enabled = 0,
+};
+
+static int __init register_snep(void)
+{
+	rv_register_monitor(&rv_snep, &rv_sched);
+	return 0;
+}
+
+static void __exit unregister_snep(void)
+{
+	rv_unregister_monitor(&rv_snep);
+}
+
+module_init(register_snep);
+module_exit(unregister_snep);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Gabriele Monaco <gmonaco@redhat.com>");
+MODULE_DESCRIPTION("snep: schedule does not enable preempt.");
diff --git a/kernel/trace/rv/monitors/snep/snep.h b/kernel/trace/rv/monitors/snep/snep.h
new file mode 100644
index 000000000000..6d16b9ad931e
--- /dev/null
+++ b/kernel/trace/rv/monitors/snep/snep.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Automatically generated C representation of snep automaton
+ * For further information about this format, see kernel documentation:
+ *   Documentation/trace/rv/deterministic_automata.rst
+ */
+
+enum states_snep {
+	non_scheduling_context_snep = 0,
+	scheduling_contex_snep,
+	state_max_snep
+};
+
+#define INVALID_STATE state_max_snep
+
+enum events_snep {
+	preempt_disable_snep = 0,
+	preempt_enable_snep,
+	schedule_entry_snep,
+	schedule_exit_snep,
+	event_max_snep
+};
+
+struct automaton_snep {
+	char *state_names[state_max_snep];
+	char *event_names[event_max_snep];
+	unsigned char function[state_max_snep][event_max_snep];
+	unsigned char initial_state;
+	bool final_states[state_max_snep];
+};
+
+static const struct automaton_snep automaton_snep = {
+	.state_names = {
+		"non_scheduling_context",
+		"scheduling_contex"
+	},
+	.event_names = {
+		"preempt_disable",
+		"preempt_enable",
+		"schedule_entry",
+		"schedule_exit"
+	},
+	.function = {
+		{ non_scheduling_context_snep, non_scheduling_context_snep, scheduling_contex_snep,               INVALID_STATE },
+		{               INVALID_STATE,               INVALID_STATE,          INVALID_STATE, non_scheduling_context_snep },
+	},
+	.initial_state = non_scheduling_context_snep,
+	.final_states = { 1, 0 },
+};
diff --git a/kernel/trace/rv/monitors/snep/snep_trace.h b/kernel/trace/rv/monitors/snep/snep_trace.h
new file mode 100644
index 000000000000..01aad49a949a
--- /dev/null
+++ b/kernel/trace/rv/monitors/snep/snep_trace.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Snippet to be included in rv_trace.h
+ */
+
+#ifdef CONFIG_RV_MON_SNEP
+DEFINE_EVENT(event_da_monitor, event_snep,
+	     TP_PROTO(char *state, char *event, char *next_state, bool final_state),
+	     TP_ARGS(state, event, next_state, final_state));
+
+DEFINE_EVENT(error_da_monitor, error_snep,
+	     TP_PROTO(char *state, char *event),
+	     TP_ARGS(state, event));
+#endif /* CONFIG_RV_MON_SNEP */