Implement state dump

[lttng-modules.git] / probes / lttng-events.h

diff --git a/probes/lttng-events.h b/probes/lttng-events.h
index d269490ec2a8ab9fb0c466f004b270bfa21d9250..cc65656d522844c45ab58bb5bc50635d7e405a9c 100644 (file)
--- a/probes/lttng-events.h
+++ b/probes/lttng-events.h
@@ -592,6 +592,17 @@ __assign_##dest##_2:                                                       \
 #undef TP_fast_assign
 #define TP_fast_assign(args...) args
 
+/*
+ * For state dump, check that "session" argument (mandatory) matches the
+ * session this event belongs to. Ensures that we write state dump data only
+ * into the started session, not into all sessions.
+ */
+#ifdef TP_SESSION_CHECK
+#define _TP_SESSION_CHECK(session, csession)   (session == csession)
+#else /* TP_SESSION_CHECK */
+#define _TP_SESSION_CHECK(session, csession)   1
+#endif /* TP_SESSION_CHECK */
+
 #undef DECLARE_EVENT_CLASS
 #define DECLARE_EVENT_CLASS(_name, _proto, _args, _tstruct, _assign, _print)  \
 static void __event_probe__##_name(void *__data, _proto)                     \
@@ -605,8 +616,12 @@ static void __event_probe__##_name(void *__data, _proto)                 \
        struct __event_typemap__##_name __typemap;                            \
        int __ret;                                                            \
                                                                              \
-       if (0)                                                                \
+       if (0) {                                                              \
                (void) __dynamic_len_idx;       /* don't warn if unused */    \
+               (void) __typemap;               /* don't warn if unused */    \
+       }                                                                     \
+       if (!_TP_SESSION_CHECK(session, __chan->session))                     \
+               return;                                                       \
        if (unlikely(!ACCESS_ONCE(__chan->session->active)))                  \
                return;                                                       \
        if (unlikely(!ACCESS_ONCE(__chan->enabled)))                          \
@@ -638,6 +653,8 @@ static void __event_probe__##_name(void *__data)                          \
        size_t __event_len, __event_align;                                    \
        int __ret;                                                            \
                                                                              \
+       if (!_TP_SESSION_CHECK(session, __chan->session))                     \
+               return;                                                       \
        if (unlikely(!ACCESS_ONCE(__chan->session->active)))                  \
                return;                                                       \
        if (unlikely(!ACCESS_ONCE(__chan->enabled)))                          \