Add kretprobe support

[deliverable/lttng-modules.git] / ltt-events.h

diff --git a/ltt-events.h b/ltt-events.h
index 8cbe8efb5c691de42d845c9442c9e5aed91c3e8d..6cc4ea3f6fed01bbcc9309dbfcdfbfb33400a21e 100644 (file)
--- a/ltt-events.h
+++ b/ltt-events.h
@@ -119,6 +119,17 @@ struct lttng_event_field {
        struct lttng_type type;
 };
 
+/*
+ * We need to keep this perf counter field separately from struct
+ * lttng_ctx_field because cpu hotplug needs fixed-location addresses.
+ */
+struct lttng_perf_counter_field {
+       struct notifier_block nb;
+       int hp_enable;
+       struct perf_event_attr *attr;
+       struct perf_event **e;  /* per-cpu array */
+};
+
 struct lttng_ctx_field {
        struct lttng_event_field event_field;
        size_t (*get_size)(size_t offset);
@@ -126,12 +137,7 @@ struct lttng_ctx_field {
                       struct lib_ring_buffer_ctx *ctx,
                       struct ltt_channel *chan);
        union {
-               struct {
-                       struct perf_event **e;  /* per-cpu array */
-                       struct notifier_block nb;
-                       int hp_enable;
-                       struct perf_event_attr *attr;
-               } perf_counter;
+               struct lttng_perf_counter_field *perf_counter;
        } u;
        void (*destroy)(struct lttng_ctx_field *field);
 };
@@ -157,6 +163,8 @@ struct lttng_probe_desc {
        struct list_head head;                  /* chain registered probes */
 };
 
+struct lttng_krp;                              /* Kretprobe handling */
+
 /*
  * ltt_event structure is referred to by the tracing fast path. It must be
  * kept small.
@@ -174,6 +182,10 @@ struct ltt_event {
                        struct kprobe kp;
                        char *symbol_name;
                } kprobe;
+               struct {
+                       struct lttng_krp *lttng_krp;
+                       char *symbol_name;
+               } kretprobe;
                struct {
                        char *symbol_name;
                } ftrace;
@@ -345,6 +357,38 @@ void lttng_kprobes_destroy_private(struct ltt_event *event)
 }
 #endif
 
+#ifdef CONFIG_KRETPROBES
+int lttng_kretprobes_register(const char *name,
+               const char *symbol_name,
+               uint64_t offset,
+               uint64_t addr,
+               struct ltt_event *event_entry,
+               struct ltt_event *event_exit);
+void lttng_kretprobes_unregister(struct ltt_event *event);
+void lttng_kretprobes_destroy_private(struct ltt_event *event);
+#else
+static inline
+int lttng_kretprobes_register(const char *name,
+               const char *symbol_name,
+               uint64_t offset,
+               uint64_t addr,
+               struct ltt_event *event_entry,
+               struct ltt_event *event_exit)
+{
+       return -ENOSYS;
+}
+
+static inline
+void lttng_kretprobes_unregister(struct ltt_event *event)
+{
+}
+
+static inline
+void lttng_kretprobes_destroy_private(struct ltt_event *event)
+{
+}
+#endif
+
 #ifdef CONFIG_DYNAMIC_FTRACE
 int lttng_ftrace_register(const char *name,
                          const char *symbol_name,