Keep event description registry instead of just name callback mapping

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

diff --git a/ltt-events.c b/ltt-events.c
index c2a6a9206304f6e5a06b4b30e55a465d0f70f589..a5ca1abaa798c83489fc604705a0ea966141ffa4 100644 (file)
--- a/ltt-events.c
+++ b/ltt-events.c
@@ -11,7 +11,7 @@
 #include <linux/mutex.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
-#include <linux/vmalloc.h>     /* For vmalloc_sync_all */
+#include "wrapper/vmalloc.h"   /* for wrapper_vmalloc_sync_all() */
 #include "ltt-events.h"
 
 static LIST_HEAD(sessions);
@@ -49,7 +49,7 @@ void ltt_session_destroy(struct ltt_session *session)
        int ret;
 
        mutex_lock(&sessions_mutex);
-       session->active = 0;
+       ACCESS_ONCE(session->active) = 0;
        list_for_each_entry(event, &session->events, list) {
                ret = _ltt_event_unregister(event);
                WARN_ON(ret);
@@ -73,7 +73,7 @@ int ltt_session_start(struct ltt_session *session)
                ret = -EBUSY;
                goto end;
        }
-       session->active = 1;
+       ACCESS_ONCE(session->active) = 1;
        synchronize_trace();    /* Wait for in-flight events to complete */
 end:
        mutex_unlock(&sessions_mutex);
@@ -89,14 +89,14 @@ int ltt_session_stop(struct ltt_session *session)
                ret = -EBUSY;
                goto end;
        }
-       session->active = 0;
+       ACCESS_ONCE(session->active) = 0;
        synchronize_trace();    /* Wait for in-flight events to complete */
 end:
        mutex_unlock(&sessions_mutex);
        return ret;
 }
 
-static struct ltt_transport *ltt_transport_find(char *name)
+static struct ltt_transport *ltt_transport_find(const char *name)
 {
        struct ltt_transport *transport;
 
@@ -108,21 +108,20 @@ static struct ltt_transport *ltt_transport_find(char *name)
 }
 
 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
-                                      int overwrite, void *buf_addr,
+                                      const char *transport_name,
+                                      void *buf_addr,
                                       size_t subbuf_size, size_t num_subbuf,
                                       unsigned int switch_timer_interval,
                                       unsigned int read_timer_interval)
 {
        struct ltt_channel *chan;
        struct ltt_transport *transport;
-       char *transport_name;
 
        mutex_lock(&sessions_mutex);
        if (session->active) {
                printk(KERN_WARNING "LTTng refusing to add channel to active session\n");
                goto active;    /* Refuse to add channel to active session */
        }
-       transport_name = overwrite ? "relay-overwrite" : "relay-discard";
        transport = ltt_transport_find(transport_name);
        if (!transport) {
                printk(KERN_WARNING "LTTng transport %s not found\n",
@@ -168,7 +167,8 @@ void _ltt_channel_destroy(struct ltt_channel *chan)
  */
 struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
                                   enum instrum_type itype,
-                                  void *probe, void *filter)
+                                  const struct lttng_event_desc *event_desc,
+                                  void *filter)
 {
        struct ltt_event *event;
        int ret;
@@ -181,17 +181,13 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
         * creation). Might require a hash if we have lots of events.
         */
        list_for_each_entry(event, &chan->session->events, list)
-               if (!strcmp(event->name, name))
+               if (!strcmp(event->desc->name, name))
                        goto exist;
        event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
        if (!event)
                goto cache_error;
-       event->name = kmalloc(strlen(name) + 1, GFP_KERNEL);
-       if (!event->name)
-               goto name_error;
-       strcpy(event->name, name);
        event->chan = chan;
-       event->probe = probe;
+       event->desc = event_desc;
        event->filter = filter;
        event->id = chan->free_event_id++;
        event->itype = itype;
@@ -199,7 +195,8 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
        smp_wmb();
        switch (itype) {
        case INSTRUM_TRACEPOINTS:
-               ret = tracepoint_probe_register(name, probe, event);
+               ret = tracepoint_probe_register(name, event_desc->probe_callback,
+                                               event);
                if (ret)
                        goto register_error;
                break;
@@ -211,8 +208,6 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name,
        return event;
 
 register_error:
-       kfree(event->name);
-name_error:
        kmem_cache_free(event_cache, event);
 cache_error:
 exist:
@@ -230,7 +225,8 @@ int _ltt_event_unregister(struct ltt_event *event)
 
        switch (event->itype) {
        case INSTRUM_TRACEPOINTS:
-               ret = tracepoint_probe_unregister(event->name, event->probe,
+               ret = tracepoint_probe_unregister(event->desc->name,
+                                                 event->desc->probe_callback,
                                                  event);
                if (ret)
                        return ret;
@@ -246,7 +242,7 @@ int _ltt_event_unregister(struct ltt_event *event)
  */
 void _ltt_event_destroy(struct ltt_event *event)
 {
-       kfree(event->name);
+       ltt_event_put(event->desc);
        list_del(&event->list);
        kmem_cache_free(event_cache, event);
 }
@@ -270,7 +266,7 @@ void ltt_transport_register(struct ltt_transport *transport)
         * registered. We deal with this here so we don't have to call
         * vmalloc_sync_all() in each module's init.
         */
-       vmalloc_sync_all();
+       wrapper_vmalloc_sync_all();
 
        mutex_lock(&sessions_mutex);
        list_add_tail(&transport->node, &ltt_transport_list);
@@ -298,16 +294,11 @@ static int __init ltt_events_init(void)
        event_cache = KMEM_CACHE(ltt_event, 0);
        if (!event_cache)
                return -ENOMEM;
-       ret = ltt_probes_init();
-       if (ret)
-               goto error;
        ret = ltt_debugfs_abi_init();
        if (ret)
                goto error_abi;
        return 0;
 error_abi:
-       ltt_probes_exit();
-error:
        kmem_cache_destroy(event_cache);
        return ret;
 }
@@ -319,7 +310,6 @@ static void __exit ltt_events_exit(void)
        struct ltt_session *session, *tmpsession;
 
        ltt_debugfs_abi_exit();
-       ltt_probes_exit();
        list_for_each_entry_safe(session, tmpsession, &sessions, list)
                ltt_session_destroy(session);
        kmem_cache_destroy(event_cache);