Update licensing info

[lttng-modules.git] / ltt-probes.c

diff --git a/ltt-probes.c b/ltt-probes.c
index dbdb50d402a2f7bbecd06a203d03fe46a3b85300..45d2dabdef22e977fe8122deeb9a5417aa07fc21 100644 (file)
--- a/ltt-probes.c
+++ b/ltt-probes.c
@@ -4,11 +4,14 @@
  * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
  * Holds LTTng probes registry.
+ *
+ * Dual LGPL v2.1/GPL v2 license.
  */
 
 #include <linux/module.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
+#include <linux/seq_file.h>
 
 #include "ltt-events.h"
 
@@ -30,11 +33,6 @@ const struct lttng_event_desc *find_event(const char *name)
        return NULL;
 }
 
-/*
- * TODO: registration of probe descriptions in dynamically allocated memory (not
- * directly in a module memory) will require some care for refcounting: it's
- * currently done by just refcounting the module in event_get/put.
- */
 int ltt_probe_register(struct lttng_probe_desc *desc)
 {
        int ret = 0;
@@ -73,18 +71,93 @@ const struct lttng_event_desc *ltt_event_get(const char *name)
 
        mutex_lock(&probe_mutex);
        event = find_event(name);
+       mutex_unlock(&probe_mutex);
        if (!event)
-               goto end;
-       ret = try_module_get(__module_text_address((unsigned long) event));
+               return NULL;
+       ret = try_module_get(event->owner);
        WARN_ON_ONCE(!ret);
-end:
-       mutex_unlock(&probe_mutex);
        return event;
 }
 EXPORT_SYMBOL_GPL(ltt_event_get);
 
 void ltt_event_put(const struct lttng_event_desc *event)
 {
-       module_put(__module_text_address((unsigned long) event));
+       module_put(event->owner);
 }
 EXPORT_SYMBOL_GPL(ltt_event_put);
+
+static
+void *tp_list_start(struct seq_file *m, loff_t *pos)
+{
+       struct lttng_probe_desc *probe_desc;
+       int iter = 0, i;
+
+       mutex_lock(&probe_mutex);
+       list_for_each_entry(probe_desc, &probe_list, head) {
+               for (i = 0; i < probe_desc->nr_events; i++) {
+                       if (iter++ >= *pos)
+                               return (void *) &probe_desc->event_desc[i];
+               }
+       }
+       /* End of list */
+       return NULL;
+}
+
+static
+void *tp_list_next(struct seq_file *m, void *p, loff_t *ppos)
+{
+       struct lttng_probe_desc *probe_desc;
+       int iter = 0, i;
+
+       (*ppos)++;
+       list_for_each_entry(probe_desc, &probe_list, head) {
+               for (i = 0; i < probe_desc->nr_events; i++) {
+                       if (iter++ >= *ppos)
+                               return (void *) &probe_desc->event_desc[i];
+               }
+       }
+       /* End of list */
+       return NULL;
+}
+
+static
+void tp_list_stop(struct seq_file *m, void *p)
+{
+       mutex_unlock(&probe_mutex);
+}
+
+static
+int tp_list_show(struct seq_file *m, void *p)
+{
+       const struct lttng_event_desc *probe_desc = p;
+
+       /*
+        * Don't export lttng internal events (metadata).
+        */
+       if (!strncmp(probe_desc->name, "lttng_", sizeof("lttng_") - 1))
+               return 0;
+       seq_printf(m,   "event { name = %s; };\n",
+                  probe_desc->name);
+       return 0;
+}
+
+static
+const struct seq_operations lttng_tracepoint_list_seq_ops = {
+       .start = tp_list_start,
+       .next = tp_list_next,
+       .stop = tp_list_stop,
+       .show = tp_list_show,
+};
+
+static
+int lttng_tracepoint_list_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &lttng_tracepoint_list_seq_ops);
+}
+
+const struct file_operations lttng_tracepoint_list_fops = {
+       .open = lttng_tracepoint_list_open,
+       .read = seq_read,
+       .llseek = seq_lseek,
+       .release = seq_release,
+};