/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2019-2022 Red Hat, Inc. Daniel Bristot de Oliveira <[email protected]>
*
* 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/
*
* For further information, see:
* Documentation/trace/rv/da_monitor_synthesis.rst
*/
#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 \
*/ \
static 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)
Codebase Browser
linux