mirror of
https://github.com/torvalds/linux.git
synced 2024-11-29 23:51:37 +00:00
d57aff2479
Add the da_monitor_synthesis.rst introduces some concepts behind the Deterministic Automata (DA) monitor synthesis and interface. Link: https://lkml.kernel.org/r/7873bdb7b2e5d2bc0b2eb6ca0b324af9a0ba27a0.1659052063.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>
545 lines
17 KiB
C
545 lines
17 KiB
C
/* 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/
|
|
*
|
|
* 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 \
|
|
*/ \
|
|
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)
|