Extract callbacks and enabled state to non-packed structure

[libside.git] / include / side / trace.h

diff --git a/include/side/trace.h b/include/side/trace.h
index f7bf90122cf5c4a4fffe5fedc99a9062c530d41e..8e0604d1c54c52b0838cd309304cfce11a5c2d30 100644 (file)
--- a/include/side/trace.h
+++ b/include/side/trace.h
@@ -650,19 +650,27 @@ struct side_tracer_dynamic_struct_visitor_ctx {
        void *priv;             /* Private tracer context. */
 } SIDE_PACKED;
 
+/*
+ * This structure is _not_ packed to allow atomic operations on its
+ * fields.
+ */
+struct side_event_state {
+       uintptr_t enabled;
+       const struct side_callback *callbacks;
+       uint32_t nr_callbacks;
+};
+
 struct side_event_description {
-       uintptr_t *enabled;
+       struct side_event_state *state;
        const char *provider_name;
        const char *event_name;
        const struct side_event_field *fields;
        const struct side_attr *attr;
-       const struct side_callback *callbacks;
        uint64_t flags;
        uint32_t version;
        uint32_t loglevel;      /* enum side_loglevel */
        uint32_t nr_fields;
        uint32_t nr_attr;
-       uint32_t nr_callbacks;
 } SIDE_PACKED;
 
 /* Event and type attributes */
@@ -1756,7 +1764,7 @@ struct side_event_description {
 #define side_arg_list(...)     __VA_ARGS__
 
 #define side_event_cond(_identifier) \
-       if (side_unlikely(__atomic_load_n(&side_event_enable__##_identifier, \
+       if (side_unlikely(__atomic_load_n(&side_event_state__##_identifier.enabled, \
                                        __ATOMIC_RELAXED)))
 
 #define side_event_call(_identifier, _sav) \
@@ -1795,21 +1803,24 @@ struct side_event_description {
                side_event_call_variadic(_identifier, SIDE_PARAM(_sav), SIDE_PARAM(_var), SIDE_PARAM_SELECT_ARG1(_, ##_attr, side_attr_list()))
 
 #define _side_define_event(_linkage, _identifier, _provider, _event, _loglevel, _fields, _flags, _attr...) \
-       _linkage uintptr_t side_event_enable__##_identifier __attribute__((section("side_event_enable"))); \
+       _linkage struct side_event_state __attribute__((section("side_event_state"))) \
+                       side_event_state__##_identifier = { \
+               .enabled = 0, \
+               .callbacks = &side_empty_callback, \
+               .nr_callbacks = 0, \
+       }; \
        _linkage struct side_event_description __attribute__((section("side_event_description"))) \
                        _identifier = { \
-               .enabled = &(side_event_enable__##_identifier), \
+               .state = &(side_event_state__##_identifier), \
                .provider_name = _provider, \
                .event_name = _event, \
                .fields = _fields, \
                .attr = SIDE_PARAM_SELECT_ARG1(_, ##_attr, side_attr_list()), \
-               .callbacks = &side_empty_callback, \
                .flags = (_flags), \
                .version = 0, \
                .loglevel = _loglevel, \
                .nr_fields = SIDE_ARRAY_SIZE(SIDE_PARAM(_fields)), \
                .nr_attr = SIDE_ARRAY_SIZE(SIDE_PARAM_SELECT_ARG1(_, ##_attr, side_attr_list())), \
-               .nr_callbacks = 0, \
        }; \
        static const struct side_event_description *side_event_ptr__##_identifier \
                __attribute__((section("side_event_description_ptr"), used)) = &(_identifier);
@@ -1839,7 +1850,7 @@ struct side_event_description {
                        _loglevel, SIDE_PARAM(_fields), SIDE_EVENT_FLAG_VARIADIC, SIDE_PARAM_SELECT_ARG1(_, ##_attr, side_attr_list()))
 
 #define side_declare_event(_identifier) \
-       extern uintptr_t side_event_enable_##_identifier; \
+       extern struct side_event_state side_event_state_##_identifier; \
        extern struct side_event_description _identifier
 
 #ifdef __cplusplus