rv: Pass va_list to reactors

The only thing the reactors can do with the passed in varargs is to
convert it into a va_list. Do that in a central helper instead.
It simplifies the reactors, removes some hairy macro-generated code
and introduces a convenient hook point to modify reactor behavior.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://lore.kernel.org/r/20251014-rv-lockdep-v1-1-0b9e51919ea8@linutronix.de
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>

diff --git a/include/linux/rv.h b/include/linux/rv.h
index 9520aab34bcbe36c730bc6ab20bed71c8eee52bf..b567b0191e67f7dfab74e2aad6de3ed63d94058d 100644 (file)
--- a/include/linux/rv.h
+++ b/include/linux/rv.h
@@ -88,7 +88,7 @@ union rv_task_monitor {
 struct rv_reactor {
        const char              *name;
        const char              *description;
-       __printf(1, 2) void     (*react)(const char *msg, ...);
+       __printf(1, 0) void     (*react)(const char *msg, va_list args);
        struct list_head        list;
 };
 #endif
@@ -102,7 +102,7 @@ struct rv_monitor {
        void                    (*reset)(void);
 #ifdef CONFIG_RV_REACTORS
        struct rv_reactor       *reactor;
-       __printf(1, 2) void     (*react)(const char *msg, ...);
+       __printf(1, 0) void     (*react)(const char *msg, va_list args);
 #endif
        struct list_head        list;
        struct rv_monitor       *parent;
@@ -119,11 +119,18 @@ void rv_put_task_monitor_slot(int slot);
 bool rv_reacting_on(void);
 int rv_unregister_reactor(struct rv_reactor *reactor);
 int rv_register_reactor(struct rv_reactor *reactor);
+__printf(2, 3)
+void rv_react(struct rv_monitor *monitor, const char *msg, ...);
 #else
 static inline bool rv_reacting_on(void)
 {
        return false;
 }
+
+__printf(2, 3)
+static inline void rv_react(struct rv_monitor *monitor, const char *msg, ...)
+{
+}
 #endif /* CONFIG_RV_REACTORS */
 
 #endif /* CONFIG_RV */

diff --git a/include/rv/da_monitor.h b/include/rv/da_monitor.h
index 17fa4f6e5ea63fad29fd4349c54720944a179e38..0cef64366538c90dab8f76fbf5d2aaacdd61e2e7 100644 (file)
--- a/include/rv/da_monitor.h
+++ b/include/rv/da_monitor.h
@@ -16,34 +16,19 @@
 #include <linux/bug.h>
 #include <linux/sched.h>
 
-#ifdef CONFIG_RV_REACTORS
-
-#define DECLARE_RV_REACTING_HELPERS(name, type)                                                        \
-static void cond_react_##name(type curr_state, type event)                                     \
-{                                                                                              \
-       if (!rv_reacting_on() || !rv_##name.react)                                              \
-               return;                                                                         \
-       rv_##name.react("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));                               \
-}
-
-#else /* CONFIG_RV_REACTOR */
-
-#define DECLARE_RV_REACTING_HELPERS(name, type)                                                        \
-static void cond_react_##name(type curr_state, type event)                                     \
-{                                                                                              \
-       return;                                                                                 \
-}
-#endif
-
 /*
  * Generic helpers for all types of deterministic automata monitors.
  */
 #define DECLARE_DA_MON_GENERIC_HELPERS(name, type)                                             \
                                                                                                \
-DECLARE_RV_REACTING_HELPERS(name, type)                                                                \
+static void react_##name(type curr_state, type event)                                          \
+{                                                                                              \
+       rv_react(&rv_##name,                                                                    \
+                "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));                                      \
+}                                                                                              \
                                                                                                \
 /*                                                                                             \
  * da_monitor_reset_##name - reset a monitor and setting it to init state                      \
@@ -126,7 +111,7 @@ da_event_##name(struct da_monitor *da_mon, enum events_##name event)                                \
        for (int i = 0; i < MAX_DA_RETRY_RACING_EVENTS; i++) {                                  \
                next_state = model_get_next_state_##name(curr_state, event);                    \
                if (next_state == INVALID_STATE) {                                              \
-                       cond_react_##name(curr_state, event);                                   \
+                       react_##name(curr_state, event);                                        \
                        trace_error_##name(model_get_state_name_##name(curr_state),             \
                                           model_get_event_name_##name(event));                 \
                        return false;                                                           \
@@ -165,7 +150,7 @@ static inline bool da_event_##name(struct da_monitor *da_mon, struct task_struct
        for (int i = 0; i < MAX_DA_RETRY_RACING_EVENTS; i++) {                                  \
                next_state = model_get_next_state_##name(curr_state, event);                    \
                if (next_state == INVALID_STATE) {                                              \
-                       cond_react_##name(curr_state, event);                                   \
+                       react_##name(curr_state, event);                                        \
                        trace_error_##name(tsk->pid,                                            \
                                           model_get_state_name_##name(curr_state),             \
                                           model_get_event_name_##name(event));                 \

diff --git a/include/rv/ltl_monitor.h b/include/rv/ltl_monitor.h
index 5368cf5fd623e74a5739d2e0b3fc2c27c4bad597..00c42b36f961a00ee473aa58f14b015308523eb0 100644 (file)
--- a/include/rv/ltl_monitor.h
+++ b/include/rv/ltl_monitor.h
@@ -16,21 +16,12 @@
 #error "Please include $(MODEL_NAME).h generated by rvgen"
 #endif
 
-#ifdef CONFIG_RV_REACTORS
 #define RV_MONITOR_NAME CONCATENATE(rv_, MONITOR_NAME)
-static struct rv_monitor RV_MONITOR_NAME;
 
-static void rv_cond_react(struct task_struct *task)
-{
-       if (!rv_reacting_on() || !RV_MONITOR_NAME.react)
-               return;
-       RV_MONITOR_NAME.react("rv: "__stringify(MONITOR_NAME)": %s[%d]: violation detected\n",
-                             task->comm, task->pid);
-}
+#ifdef CONFIG_RV_REACTORS
+static struct rv_monitor RV_MONITOR_NAME;
 #else
-static void rv_cond_react(struct task_struct *task)
-{
-}
+extern struct rv_monitor RV_MONITOR_NAME;
 #endif
 
 static int ltl_monitor_slot = RV_PER_TASK_MONITOR_INIT;
@@ -98,7 +89,8 @@ static void ltl_monitor_destroy(void)
 static void ltl_illegal_state(struct task_struct *task, struct ltl_monitor *mon)
 {
        CONCATENATE(trace_error_, MONITOR_NAME)(task);
-       rv_cond_react(task);
+       rv_react(&RV_MONITOR_NAME, "rv: "__stringify(MONITOR_NAME)": %s[%d]: violation detected\n",
+                task->comm, task->pid);
 }
 
 static void ltl_attempt_start(struct task_struct *task, struct ltl_monitor *mon)

diff --git a/kernel/trace/rv/reactor_panic.c b/kernel/trace/rv/reactor_panic.c
index 74c6bcc2c7494408770881dda2b0de885c5eb88c..76537b8a4343cbd0d715f60db3cc8868e71c1c0b 100644 (file)
--- a/kernel/trace/rv/reactor_panic.c
+++ b/kernel/trace/rv/reactor_panic.c
@@ -13,13 +13,9 @@
 #include <linux/init.h>
 #include <linux/rv.h>
 
-__printf(1, 2) static void rv_panic_reaction(const char *msg, ...)
+__printf(1, 0) static void rv_panic_reaction(const char *msg, va_list args)
 {
-       va_list args;
-
-       va_start(args, msg);
        vpanic(msg, args);
-       va_end(args);
 }
 
 static struct rv_reactor rv_panic = {

diff --git a/kernel/trace/rv/reactor_printk.c b/kernel/trace/rv/reactor_printk.c
index 2dae2916c05fd17397195e37d9b42d24cea24b9c..48c934e315b31c14d3a5b4fa3ec334ef71f9e390 100644 (file)
--- a/kernel/trace/rv/reactor_printk.c
+++ b/kernel/trace/rv/reactor_printk.c
@@ -12,13 +12,9 @@
 #include <linux/init.h>
 #include <linux/rv.h>
 
-__printf(1, 2) static void rv_printk_reaction(const char *msg, ...)
+__printf(1, 0) static void rv_printk_reaction(const char *msg, va_list args)
 {
-       va_list args;
-
-       va_start(args, msg);
        vprintk_deferred(msg, args);
-       va_end(args);
 }
 
 static struct rv_reactor rv_printk = {

diff --git a/kernel/trace/rv/rv_reactors.c b/kernel/trace/rv/rv_reactors.c
index d32859fec238371b5721e08cf6558f0805565f7b..cb1a5968055abb22439a066b4e25dad98f078389 100644 (file)
--- a/kernel/trace/rv/rv_reactors.c
+++ b/kernel/trace/rv/rv_reactors.c
@@ -438,7 +438,7 @@ int reactor_populate_monitor(struct rv_monitor *mon)
 /*
  * Nop reactor register
  */
-__printf(1, 2) static void rv_nop_reaction(const char *msg, ...)
+__printf(1, 0) static void rv_nop_reaction(const char *msg, va_list args)
 {
 }
 
@@ -477,3 +477,17 @@ int init_rv_reactors(struct dentry *root_dir)
 out_err:
        return -ENOMEM;
 }
+
+void rv_react(struct rv_monitor *monitor, const char *msg, ...)
+{
+       va_list args;
+
+       if (!rv_reacting_on() || !monitor->react)
+               return;
+
+       va_start(args, msg);
+
+       monitor->react(msg, args);
+
+       va_end(args);
+}