rv/include: Add deterministic automata monitor definition via C macros
authorDaniel Bristot de Oliveira <bristot@kernel.org>
Fri, 29 Jul 2022 09:38:43 +0000 (11:38 +0200)
committerSteven Rostedt (Google) <rostedt@goodmis.org>
Sat, 30 Jul 2022 18:01:28 +0000 (14:01 -0400)
In Linux terms, the runtime verification monitors are encapsulated
inside the "RV monitor" abstraction. The "RV monitor" includes a set
of instances of the monitor (per-cpu monitor, per-task monitor, and
so on), the helper functions that glue the monitor to the system
reference model, and the trace output as a reaction for event parsing
and exceptions, as depicted below:

Linux  +----- RV Monitor ----------------------------------+ Formal
 Realm |                                                   |  Realm
 +-------------------+     +----------------+     +-----------------+
 |   Linux kernel    |     |     Monitor    |     |     Reference   |
 |     Tracing       |  -> |   Instance(s)  | <-  |       Model     |
 | (instrumentation) |     | (verification) |     | (specification) |
 +-------------------+     +----------------+     +-----------------+
        |                          |                       |
        |                          V                       |
        |                     +----------+                 |
        |                     | Reaction |                 |
        |                     +--+--+--+-+                 |
        |                        |  |  |                   |
        |                        |  |  +-> trace output ?  |
        +------------------------|--|----------------------+
                                 |  +----> panic ?
                                 +-------> <user-specified>

Add the rv/da_monitor.h, enabling automatic code generation for the
*Monitor Instance(s)* using C macros, and code to support it.

The benefits of the usage of macro for monitor synthesis are 3-fold as it:

- Reduces the code duplication;
- Facilitates the bug fix/improvement;
- Avoids the case of developers changing the core of the monitor code
  to manipulate the model in a (let's say) non-standard way.

This initial implementation presents three different types of monitor
instances:

- DECLARE_DA_MON_GLOBAL(name, type)
- DECLARE_DA_MON_PER_CPU(name, type)
- DECLARE_DA_MON_PER_TASK(name, type)

The first declares the functions for a global deterministic automata monitor,
the second for monitors with per-cpu instances, and the third with per-task
instances.

Link: https://lkml.kernel.org/r/51b0bf425a281e226dfeba7401d2115d6091f84e.1659052063.git.bristot@kernel.org
Cc: Wim Van Sebroeck <wim@linux-watchdog.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Gabriele Paoloni <gpaoloni@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Tao Zhou <tao.zhou@linux.dev>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
include/linux/rv.h
include/rv/da_monitor.h [new file with mode: 0644]
include/trace/events/rv.h [new file with mode: 0644]
kernel/fork.c
kernel/trace/rv/Kconfig
kernel/trace/rv/rv.c

index dcce569..8883b41 100644 (file)
@@ -7,7 +7,16 @@
 #ifndef _LINUX_RV_H
 #define _LINUX_RV_H
 
+#define MAX_DA_NAME_LEN        24
+
 #ifdef CONFIG_RV
+/*
+ * Deterministic automaton per-object variables.
+ */
+struct da_monitor {
+       bool            monitoring;
+       unsigned int    curr_state;
+};
 
 /*
  * Per-task RV monitors count. Nowadays fixed in RV_PER_TASK_MONITORS.
@@ -22,6 +31,7 @@
  * Futher monitor types are expected, so make this a union.
  */
 union rv_task_monitor {
+       struct da_monitor da_mon;
 };
 
 #ifdef CONFIG_RV_REACTORS
diff --git a/include/rv/da_monitor.h b/include/rv/da_monitor.h
new file mode 100644 (file)
index 0000000..001bc29
--- /dev/null
@@ -0,0 +1,541 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019-2022 Red Hat, Inc. Daniel Bristot de Oliveira <bristot@kernel.org>
+ *
+ * Deterministic automata (DA) monitor functions, to be used together
+ * with automata models in C generated by the dot2k tool.
+ *
+ * The dot2k tool is available at tools/verification/dot2k/
+ */
+
+#include <rv/automata.h>
+#include <linux/rv.h>
+#include <linux/bug.h>
+
+#ifdef CONFIG_RV_REACTORS
+
+#define DECLARE_RV_REACTING_HELPERS(name, type)                                                        \
+static char REACT_MSG_##name[1024];                                                            \
+                                                                                               \
+static inline char *format_react_msg_##name(type curr_state, type event)                       \
+{                                                                                              \
+       snprintf(REACT_MSG_##name, 1024,                                                        \
+                "rv: monitor %s does not allow event %s on state %s\n",                        \
+                #name,                                                                         \
+                model_get_event_name_##name(event),                                            \
+                model_get_state_name_##name(curr_state));                                      \
+       return REACT_MSG_##name;                                                                \
+}                                                                                              \
+                                                                                               \
+static void cond_react_##name(char *msg)                                                       \
+{                                                                                              \
+       if (rv_##name.react)                                                                    \
+               rv_##name.react(msg);                                                           \
+}                                                                                              \
+                                                                                               \
+static bool rv_reacting_on_##name(void)                                                                \
+{                                                                                              \
+       return rv_reacting_on();                                                                \
+}
+
+#else /* CONFIG_RV_REACTOR */
+
+#define DECLARE_RV_REACTING_HELPERS(name, type)                                                        \
+static inline char *format_react_msg_##name(type curr_state, type event)                       \
+{                                                                                              \
+       return NULL;                                                                            \
+}                                                                                              \
+                                                                                               \
+static void cond_react_##name(char *msg)                                                       \
+{                                                                                              \
+       return;                                                                                 \
+}                                                                                              \
+                                                                                               \
+static bool rv_reacting_on_##name(void)                                                                \
+{                                                                                              \
+       return 0;                                                                               \
+}
+#endif
+
+/*
+ * Generic helpers for all types of deterministic automata monitors.
+ */
+#define DECLARE_DA_MON_GENERIC_HELPERS(name, type)                                             \
+                                                                                               \
+DECLARE_RV_REACTING_HELPERS(name, type)                                                                \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_reset_##name - reset a monitor and setting it to init state                      \
+ */                                                                                            \
+static inline void da_monitor_reset_##name(struct da_monitor *da_mon)                          \
+{                                                                                              \
+       da_mon->monitoring = 0;                                                                 \
+       da_mon->curr_state = model_get_initial_state_##name();                                  \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_curr_state_##name - return the current state                                     \
+ */                                                                                            \
+static inline type da_monitor_curr_state_##name(struct da_monitor *da_mon)                     \
+{                                                                                              \
+       return da_mon->curr_state;                                                              \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_set_state_##name - set the new current state                                     \
+ */                                                                                            \
+static inline void                                                                             \
+da_monitor_set_state_##name(struct da_monitor *da_mon, enum states_##name state)               \
+{                                                                                              \
+       da_mon->curr_state = state;                                                             \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_start_##name - start monitoring                                                  \
+ *                                                                                             \
+ * The monitor will ignore all events until monitoring is set to true. This                    \
+ * function needs to be called to tell the monitor to start monitoring.                                \
+ */                                                                                            \
+static inline void da_monitor_start_##name(struct da_monitor *da_mon)                          \
+{                                                                                              \
+       da_mon->curr_state = model_get_initial_state_##name();                                  \
+       da_mon->monitoring = 1;                                                                 \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitoring_##name - returns true if the monitor is processing events                     \
+ */                                                                                            \
+static inline bool da_monitoring_##name(struct da_monitor *da_mon)                             \
+{                                                                                              \
+       return da_mon->monitoring;                                                              \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_enabled_##name - checks if the monitor is enabled                                        \
+ */                                                                                            \
+static inline bool da_monitor_enabled_##name(void)                                             \
+{                                                                                              \
+       /* global switch */                                                                     \
+       if (unlikely(!rv_monitoring_on()))                                                      \
+               return 0;                                                                       \
+                                                                                               \
+       /* monitor enabled */                                                                   \
+       if (unlikely(!rv_##name.enabled))                                                       \
+               return 0;                                                                       \
+                                                                                               \
+       return 1;                                                                               \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_handling_event_##name - checks if the monitor is ready to handle events          \
+ */                                                                                            \
+static inline bool da_monitor_handling_event_##name(struct da_monitor *da_mon)                 \
+{                                                                                              \
+                                                                                               \
+       if (!da_monitor_enabled_##name())                                                       \
+               return 0;                                                                       \
+                                                                                               \
+       /* monitor is actually monitoring */                                                    \
+       if (unlikely(!da_monitoring_##name(da_mon)))                                            \
+               return 0;                                                                       \
+                                                                                               \
+       return 1;                                                                               \
+}
+
+/*
+ * Event handler for implicit monitors. Implicit monitor is the one which the
+ * handler does not need to specify which da_monitor to manipulate. Examples
+ * of implicit monitor are the per_cpu or the global ones.
+ */
+#define DECLARE_DA_MON_MODEL_HANDLER_IMPLICIT(name, type)                                      \
+                                                                                               \
+static inline bool                                                                             \
+da_event_##name(struct da_monitor *da_mon, enum events_##name event)                           \
+{                                                                                              \
+       type curr_state = da_monitor_curr_state_##name(da_mon);                                 \
+       type next_state = model_get_next_state_##name(curr_state, event);                       \
+                                                                                               \
+       if (next_state != INVALID_STATE) {                                                      \
+               da_monitor_set_state_##name(da_mon, next_state);                                \
+                                                                                               \
+               trace_event_##name(model_get_state_name_##name(curr_state),                     \
+                                  model_get_event_name_##name(event),                          \
+                                  model_get_state_name_##name(next_state),                     \
+                                  model_is_final_state_##name(next_state));                    \
+                                                                                               \
+               return true;                                                                    \
+       }                                                                                       \
+                                                                                               \
+       if (rv_reacting_on_##name())                                                            \
+               cond_react_##name(format_react_msg_##name(curr_state, event));                  \
+                                                                                               \
+       trace_error_##name(model_get_state_name_##name(curr_state),                             \
+                          model_get_event_name_##name(event));                                 \
+                                                                                               \
+       return false;                                                                           \
+}                                                                                              \
+
+/*
+ * Event handler for per_task monitors.
+ */
+#define DECLARE_DA_MON_MODEL_HANDLER_PER_TASK(name, type)                                      \
+                                                                                               \
+static inline bool da_event_##name(struct da_monitor *da_mon, struct task_struct *tsk,         \
+                                  enum events_##name event)                                    \
+{                                                                                              \
+       type curr_state = da_monitor_curr_state_##name(da_mon);                                 \
+       type next_state = model_get_next_state_##name(curr_state, event);                       \
+                                                                                               \
+       if (next_state != INVALID_STATE) {                                                      \
+               da_monitor_set_state_##name(da_mon, next_state);                                \
+                                                                                               \
+               trace_event_##name(tsk->pid,                                                    \
+                                  model_get_state_name_##name(curr_state),                     \
+                                  model_get_event_name_##name(event),                          \
+                                  model_get_state_name_##name(next_state),                     \
+                                  model_is_final_state_##name(next_state));                    \
+                                                                                               \
+               return true;                                                                    \
+       }                                                                                       \
+                                                                                               \
+       if (rv_reacting_on_##name())                                                            \
+               cond_react_##name(format_react_msg_##name(curr_state, event));                  \
+                                                                                               \
+       trace_error_##name(tsk->pid,                                                            \
+                          model_get_state_name_##name(curr_state),                             \
+                          model_get_event_name_##name(event));                                 \
+                                                                                               \
+       return false;                                                                           \
+}
+
+/*
+ * Functions to define, init and get a global monitor.
+ */
+#define DECLARE_DA_MON_INIT_GLOBAL(name, type)                                                 \
+                                                                                               \
+/*                                                                                             \
+ * global monitor (a single variable)                                                          \
+ */                                                                                            \
+static struct da_monitor da_mon_##name;                                                                \
+                                                                                               \
+/*                                                                                             \
+ * da_get_monitor_##name - return the global monitor address                                   \
+ */                                                                                            \
+static struct da_monitor *da_get_monitor_##name(void)                                          \
+{                                                                                              \
+       return &da_mon_##name;                                                                  \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_reset_all_##name - reset the single monitor                                      \
+ */                                                                                            \
+static void da_monitor_reset_all_##name(void)                                                  \
+{                                                                                              \
+       da_monitor_reset_##name(da_get_monitor_##name());                                       \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_init_##name - initialize a monitor                                               \
+ */                                                                                            \
+static inline int da_monitor_init_##name(void)                                                 \
+{                                                                                              \
+       da_monitor_reset_all_##name();                                                          \
+       return 0;                                                                               \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_destroy_##name - destroy the monitor                                             \
+ */                                                                                            \
+static inline void da_monitor_destroy_##name(void)                                             \
+{                                                                                              \
+       return;                                                                                 \
+}
+
+/*
+ * Functions to define, init and get a per-cpu monitor.
+ */
+#define DECLARE_DA_MON_INIT_PER_CPU(name, type)                                                        \
+                                                                                               \
+/*                                                                                             \
+ * per-cpu monitor variables                                                                   \
+ */                                                                                            \
+DEFINE_PER_CPU(struct da_monitor, da_mon_##name);                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_get_monitor_##name - return current CPU monitor address                                  \
+ */                                                                                            \
+static struct da_monitor *da_get_monitor_##name(void)                                          \
+{                                                                                              \
+       return this_cpu_ptr(&da_mon_##name);                                                    \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_reset_all_##name - reset all CPUs' monitor                                       \
+ */                                                                                            \
+static void da_monitor_reset_all_##name(void)                                                  \
+{                                                                                              \
+       struct da_monitor *da_mon;                                                              \
+       int cpu;                                                                                \
+       for_each_cpu(cpu, cpu_online_mask) {                                                    \
+               da_mon = per_cpu_ptr(&da_mon_##name, cpu);                                      \
+               da_monitor_reset_##name(da_mon);                                                \
+       }                                                                                       \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_init_##name - initialize all CPUs' monitor                                       \
+ */                                                                                            \
+static inline int da_monitor_init_##name(void)                                                 \
+{                                                                                              \
+       da_monitor_reset_all_##name();                                                          \
+       return 0;                                                                               \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_destroy_##name - destroy the monitor                                             \
+ */                                                                                            \
+static inline void da_monitor_destroy_##name(void)                                             \
+{                                                                                              \
+       return;                                                                                 \
+}
+
+/*
+ * Functions to define, init and get a per-task monitor.
+ */
+#define DECLARE_DA_MON_INIT_PER_TASK(name, type)                                               \
+                                                                                               \
+/*                                                                                             \
+ * The per-task monitor is stored a vector in the task struct. This variable                   \
+ * stores the position on the vector reserved for this monitor.                                        \
+ */                                                                                            \
+static int task_mon_slot_##name = RV_PER_TASK_MONITOR_INIT;                                    \
+                                                                                               \
+/*                                                                                             \
+ * da_get_monitor_##name - return the monitor in the allocated slot for tsk                    \
+ */                                                                                            \
+static inline struct da_monitor *da_get_monitor_##name(struct task_struct *tsk)                        \
+{                                                                                              \
+       return &tsk->rv[task_mon_slot_##name].da_mon;                                           \
+}                                                                                              \
+                                                                                               \
+static void da_monitor_reset_all_##name(void)                                                  \
+{                                                                                              \
+       struct task_struct *g, *p;                                                              \
+                                                                                               \
+       read_lock(&tasklist_lock);                                                              \
+       for_each_process_thread(g, p)                                                           \
+               da_monitor_reset_##name(da_get_monitor_##name(p));                              \
+       read_unlock(&tasklist_lock);                                                            \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_init_##name - initialize the per-task monitor                                    \
+ *                                                                                             \
+ * Try to allocate a slot in the task's vector of monitors. If there                           \
+ * is an available slot, use it and reset all task's monitor.                                  \
+ */                                                                                            \
+static int da_monitor_init_##name(void)                                                                \
+{                                                                                              \
+       int slot;                                                                               \
+                                                                                               \
+       slot = rv_get_task_monitor_slot();                                                      \
+       if (slot < 0 || slot >= RV_PER_TASK_MONITOR_INIT)                                       \
+               return slot;                                                                    \
+                                                                                               \
+       task_mon_slot_##name = slot;                                                            \
+                                                                                               \
+       da_monitor_reset_all_##name();                                                          \
+       return 0;                                                                               \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_monitor_destroy_##name - return the allocated slot                                       \
+ */                                                                                            \
+static inline void da_monitor_destroy_##name(void)                                             \
+{                                                                                              \
+       if (task_mon_slot_##name == RV_PER_TASK_MONITOR_INIT) {                                 \
+               WARN_ONCE(1, "Disabling a disabled monitor: " #name);                           \
+               return;                                                                         \
+       }                                                                                       \
+       rv_put_task_monitor_slot(task_mon_slot_##name);                                         \
+       task_mon_slot_##name = RV_PER_TASK_MONITOR_INIT;                                        \
+       return;                                                                                 \
+}
+
+/*
+ * Handle event for implicit monitor: da_get_monitor_##name() will figure out
+ * the monitor.
+ */
+#define DECLARE_DA_MON_MONITOR_HANDLER_IMPLICIT(name, type)                                    \
+                                                                                               \
+static inline void __da_handle_event_##name(struct da_monitor *da_mon,                         \
+                                           enum events_##name event)                           \
+{                                                                                              \
+       bool retval;                                                                            \
+                                                                                               \
+       retval = da_event_##name(da_mon, event);                                                \
+       if (!retval)                                                                            \
+               da_monitor_reset_##name(da_mon);                                                \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_handle_event_##name - handle an event                                                    \
+ */                                                                                            \
+static inline void da_handle_event_##name(enum events_##name event)                            \
+{                                                                                              \
+       struct da_monitor *da_mon = da_get_monitor_##name();                                    \
+       bool retval;                                                                            \
+                                                                                               \
+       retval = da_monitor_handling_event_##name(da_mon);                                      \
+       if (!retval)                                                                            \
+               return;                                                                         \
+                                                                                               \
+       __da_handle_event_##name(da_mon, event);                                                \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_handle_start_event_##name - start monitoring or handle event                             \
+ *                                                                                             \
+ * This function is used to notify the monitor that the system is returning                    \
+ * to the initial state, so the monitor can start monitoring in the next event.                        \
+ * Thus:                                                                                       \
+ *                                                                                             \
+ * If the monitor already started, handle the event.                                           \
+ * If the monitor did not start yet, start the monitor but skip the event.                     \
+ */                                                                                            \
+static inline bool da_handle_start_event_##name(enum events_##name event)                      \
+{                                                                                              \
+       struct da_monitor *da_mon;                                                              \
+                                                                                               \
+       if (!da_monitor_enabled_##name())                                                       \
+               return 0;                                                                       \
+                                                                                               \
+       da_mon = da_get_monitor_##name();                                                       \
+                                                                                               \
+       if (unlikely(!da_monitoring_##name(da_mon))) {                                          \
+               da_monitor_start_##name(da_mon);                                                \
+               return 0;                                                                       \
+       }                                                                                       \
+                                                                                               \
+       __da_handle_event_##name(da_mon, event);                                                \
+                                                                                               \
+       return 1;                                                                               \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_handle_start_run_event_##name - start monitoring and handle event                                \
+ *                                                                                             \
+ * This function is used to notify the monitor that the system is in the                       \
+ * initial state, so the monitor can start monitoring and handling event.                      \
+ */                                                                                            \
+static inline bool da_handle_start_run_event_##name(enum events_##name event)                  \
+{                                                                                              \
+       struct da_monitor *da_mon;                                                              \
+                                                                                               \
+       if (!da_monitor_enabled_##name())                                                       \
+               return 0;                                                                       \
+                                                                                               \
+       da_mon = da_get_monitor_##name();                                                       \
+                                                                                               \
+       if (unlikely(!da_monitoring_##name(da_mon)))                                            \
+               da_monitor_start_##name(da_mon);                                                \
+                                                                                               \
+       __da_handle_event_##name(da_mon, event);                                                \
+                                                                                               \
+       return 1;                                                                               \
+}
+
+/*
+ * Handle event for per task.
+ */
+#define DECLARE_DA_MON_MONITOR_HANDLER_PER_TASK(name, type)                                    \
+                                                                                               \
+static inline void                                                                             \
+__da_handle_event_##name(struct da_monitor *da_mon, struct task_struct *tsk,                   \
+                        enum events_##name event)                                              \
+{                                                                                              \
+       bool retval;                                                                            \
+                                                                                               \
+       retval = da_event_##name(da_mon, tsk, event);                                           \
+       if (!retval)                                                                            \
+               da_monitor_reset_##name(da_mon);                                                \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_handle_event_##name - handle an event                                                    \
+ */                                                                                            \
+static inline void                                                                             \
+da_handle_event_##name(struct task_struct *tsk, enum events_##name event)                      \
+{                                                                                              \
+       struct da_monitor *da_mon = da_get_monitor_##name(tsk);                                 \
+       bool retval;                                                                            \
+                                                                                               \
+       retval = da_monitor_handling_event_##name(da_mon);                                      \
+       if (!retval)                                                                            \
+               return;                                                                         \
+                                                                                               \
+       __da_handle_event_##name(da_mon, tsk, event);                                           \
+}                                                                                              \
+                                                                                               \
+/*                                                                                             \
+ * da_handle_start_event_##name - start monitoring or handle event                             \
+ *                                                                                             \
+ * This function is used to notify the monitor that the system is returning                    \
+ * to the initial state, so the monitor can start monitoring in the next event.                        \
+ * Thus:                                                                                       \
+ *                                                                                             \
+ * If the monitor already started, handle the event.                                           \
+ * If the monitor did not start yet, start the monitor but skip the event.                     \
+ */                                                                                            \
+static inline bool                                                                             \
+da_handle_start_event_##name(struct task_struct *tsk, enum events_##name event)                        \
+{                                                                                              \
+       struct da_monitor *da_mon;                                                              \
+                                                                                               \
+       if (!da_monitor_enabled_##name())                                                       \
+               return 0;                                                                       \
+                                                                                               \
+       da_mon = da_get_monitor_##name(tsk);                                                    \
+                                                                                               \
+       if (unlikely(!da_monitoring_##name(da_mon))) {                                          \
+               da_monitor_start_##name(da_mon);                                                \
+               return 0;                                                                       \
+       }                                                                                       \
+                                                                                               \
+       __da_handle_event_##name(da_mon, tsk, event);                                           \
+                                                                                               \
+       return 1;                                                                               \
+}
+
+/*
+ * Entry point for the global monitor.
+ */
+#define DECLARE_DA_MON_GLOBAL(name, type)                                                      \
+                                                                                               \
+DECLARE_AUTOMATA_HELPERS(name, type)                                                           \
+DECLARE_DA_MON_GENERIC_HELPERS(name, type)                                                     \
+DECLARE_DA_MON_MODEL_HANDLER_IMPLICIT(name, type)                                              \
+DECLARE_DA_MON_INIT_GLOBAL(name, type)                                                         \
+DECLARE_DA_MON_MONITOR_HANDLER_IMPLICIT(name, type)
+
+/*
+ * Entry point for the per-cpu monitor.
+ */
+#define DECLARE_DA_MON_PER_CPU(name, type)                                                     \
+                                                                                               \
+DECLARE_AUTOMATA_HELPERS(name, type)                                                           \
+DECLARE_DA_MON_GENERIC_HELPERS(name, type)                                                     \
+DECLARE_DA_MON_MODEL_HANDLER_IMPLICIT(name, type)                                              \
+DECLARE_DA_MON_INIT_PER_CPU(name, type)                                                                \
+DECLARE_DA_MON_MONITOR_HANDLER_IMPLICIT(name, type)
+
+/*
+ * Entry point for the per-task monitor.
+ */
+#define DECLARE_DA_MON_PER_TASK(name, type)                                                    \
+                                                                                               \
+DECLARE_AUTOMATA_HELPERS(name, type)                                                           \
+DECLARE_DA_MON_GENERIC_HELPERS(name, type)                                                     \
+DECLARE_DA_MON_MODEL_HANDLER_PER_TASK(name, type)                                              \
+DECLARE_DA_MON_INIT_PER_TASK(name, type)                                                       \
+DECLARE_DA_MON_MONITOR_HANDLER_PER_TASK(name, type)
diff --git a/include/trace/events/rv.h b/include/trace/events/rv.h
new file mode 100644 (file)
index 0000000..20a2e09
--- /dev/null
@@ -0,0 +1,120 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM rv
+
+#if !defined(_TRACE_RV_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_RV_H
+
+#include <linux/rv.h>
+#include <linux/tracepoint.h>
+
+#ifdef CONFIG_DA_MON_EVENTS_IMPLICIT
+DECLARE_EVENT_CLASS(event_da_monitor,
+
+       TP_PROTO(char *state, char *event, char *next_state, bool final_state),
+
+       TP_ARGS(state, event, next_state, final_state),
+
+       TP_STRUCT__entry(
+               __array(        char,   state,          MAX_DA_NAME_LEN )
+               __array(        char,   event,          MAX_DA_NAME_LEN )
+               __array(        char,   next_state,     MAX_DA_NAME_LEN )
+               __field(        bool,   final_state                     )
+       ),
+
+       TP_fast_assign(
+               memcpy(__entry->state,          state,          MAX_DA_NAME_LEN);
+               memcpy(__entry->event,          event,          MAX_DA_NAME_LEN);
+               memcpy(__entry->next_state,     next_state,     MAX_DA_NAME_LEN);
+               __entry->final_state            = final_state;
+       ),
+
+       TP_printk("%s x %s -> %s %s",
+               __entry->state,
+               __entry->event,
+               __entry->next_state,
+               __entry->final_state ? "(final)" : "")
+);
+
+DECLARE_EVENT_CLASS(error_da_monitor,
+
+       TP_PROTO(char *state, char *event),
+
+       TP_ARGS(state, event),
+
+       TP_STRUCT__entry(
+               __array(        char,   state,          MAX_DA_NAME_LEN )
+               __array(        char,   event,          MAX_DA_NAME_LEN )
+       ),
+
+       TP_fast_assign(
+               memcpy(__entry->state,          state,          MAX_DA_NAME_LEN);
+               memcpy(__entry->event,          event,          MAX_DA_NAME_LEN);
+       ),
+
+       TP_printk("event %s not expected in the state %s",
+               __entry->event,
+               __entry->state)
+);
+#endif /* CONFIG_DA_MON_EVENTS_IMPLICIT */
+
+#ifdef CONFIG_DA_MON_EVENTS_ID
+DECLARE_EVENT_CLASS(event_da_monitor_id,
+
+       TP_PROTO(int id, char *state, char *event, char *next_state, bool final_state),
+
+       TP_ARGS(id, state, event, next_state, final_state),
+
+       TP_STRUCT__entry(
+               __field(        int,    id                              )
+               __array(        char,   state,          MAX_DA_NAME_LEN )
+               __array(        char,   event,          MAX_DA_NAME_LEN )
+               __array(        char,   next_state,     MAX_DA_NAME_LEN )
+               __field(        bool,   final_state                     )
+       ),
+
+       TP_fast_assign(
+               memcpy(__entry->state,          state,          MAX_DA_NAME_LEN);
+               memcpy(__entry->event,          event,          MAX_DA_NAME_LEN);
+               memcpy(__entry->next_state,     next_state,     MAX_DA_NAME_LEN);
+               __entry->id                     = id;
+               __entry->final_state            = final_state;
+       ),
+
+       TP_printk("%d: %s x %s -> %s %s",
+               __entry->id,
+               __entry->state,
+               __entry->event,
+               __entry->next_state,
+               __entry->final_state ? "(final)" : "")
+);
+
+DECLARE_EVENT_CLASS(error_da_monitor_id,
+
+       TP_PROTO(int id, char *state, char *event),
+
+       TP_ARGS(id, state, event),
+
+       TP_STRUCT__entry(
+               __field(        int,    id                              )
+               __array(        char,   state,          MAX_DA_NAME_LEN )
+               __array(        char,   event,          MAX_DA_NAME_LEN )
+       ),
+
+       TP_fast_assign(
+               memcpy(__entry->state,          state,          MAX_DA_NAME_LEN);
+               memcpy(__entry->event,          event,          MAX_DA_NAME_LEN);
+               __entry->id                     = id;
+       ),
+
+       TP_printk("%d: event %s not expected in the state %s",
+               __entry->id,
+               __entry->event,
+               __entry->state)
+);
+#endif /* CONFIG_DA_MON_EVENTS_ID */
+#endif /* _TRACE_RV_H */
+
+/* This part ust be outside protection */
+#undef TRACE_INCLUDE_PATH
+#include <trace/define_trace.h>
index 9d44f2d..6f1f82c 100644 (file)
@@ -1964,6 +1964,18 @@ static void copy_oom_score_adj(u64 clone_flags, struct task_struct *tsk)
        mutex_unlock(&oom_adj_mutex);
 }
 
+#ifdef CONFIG_RV
+static void rv_task_fork(struct task_struct *p)
+{
+       int i;
+
+       for (i = 0; i < RV_PER_TASK_MONITORS; i++)
+               p->rv[i].da_mon.monitoring = false;
+}
+#else
+#define rv_task_fork(p) do {} while (0)
+#endif
+
 /*
  * This creates a new process as a copy of the old one,
  * but does not actually start it yet.
@@ -2399,6 +2411,8 @@ static __latent_entropy struct task_struct *copy_process(
         */
        copy_seccomp(p);
 
+       rv_task_fork(p);
+
        rseq_fork(p, clone_flags);
 
        /* Don't start children in a dying pid namespace */
index 3eb5d48..8714800 100644 (file)
@@ -1,5 +1,16 @@
 # SPDX-License-Identifier: GPL-2.0-only
 #
+config DA_MON_EVENTS
+       bool
+
+config DA_MON_EVENTS_IMPLICIT
+       select DA_MON_EVENTS
+       bool
+
+config DA_MON_EVENTS_ID
+       select DA_MON_EVENTS
+       bool
+
 menuconfig RV
        bool "Runtime Verification"
        depends on TRACING
index 45cf64e..df6678c 100644 (file)
 #include <linux/init.h>
 #include <linux/slab.h>
 
+#ifdef CONFIG_DA_MON_EVENTS
+#define CREATE_TRACE_POINTS
+#include <trace/events/rv.h>
+#endif
+
 #include "rv.h"
 
 DEFINE_MUTEX(rv_interface_lock);