Remove debugfs file (keep only proc file)

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

diff --git a/ltt-events.c b/ltt-events.c
index 3532dee5a1c8d46e246fa14c8e6c07a1257f26c7..03dbb2036af923e3c60841783bca3f46ac528c00 100644 (file)
--- a/ltt-events.c
+++ b/ltt-events.c
@@ -66,6 +66,10 @@ void ltt_session_destroy(struct ltt_session *session)
 
        mutex_lock(&sessions_mutex);
        ACCESS_ONCE(session->active) = 0;
+       list_for_each_entry(chan, &session->chan, list) {
+               ret = lttng_syscalls_unregister(chan);
+               WARN_ON(ret);
+       }
        list_for_each_entry(event, &session->events, list) {
                ret = _ltt_event_unregister(event);
                WARN_ON(ret);
@@ -262,7 +266,8 @@ void _ltt_channel_destroy(struct ltt_channel *chan)
  */
 struct ltt_event *ltt_event_create(struct ltt_channel *chan,
                                   struct lttng_kernel_event *event_param,
-                                  void *filter)
+                                  void *filter,
+                                  const struct lttng_event_desc *internal_desc)
 {
        struct ltt_event *event;
        int ret;
@@ -309,6 +314,49 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan,
                ret = try_module_get(event->desc->owner);
                WARN_ON_ONCE(!ret);
                break;
+       case LTTNG_KERNEL_KRETPROBE:
+       {
+               struct ltt_event *event_return;
+
+               /* kretprobe defines 2 events */
+               event_return =
+                       kmem_cache_zalloc(event_cache, GFP_KERNEL);
+               if (!event_return)
+                       goto register_error;
+               event_return->chan = chan;
+               event_return->filter = filter;
+               event_return->id = chan->free_event_id++;
+               event_return->enabled = 1;
+               event_return->instrumentation = event_param->instrumentation;
+               /*
+                * Populate ltt_event structure before kretprobe registration.
+                */
+               smp_wmb();
+               ret = lttng_kretprobes_register(event_param->name,
+                               event_param->u.kretprobe.symbol_name,
+                               event_param->u.kretprobe.offset,
+                               event_param->u.kretprobe.addr,
+                               event, event_return);
+               if (ret) {
+                       kmem_cache_free(event_cache, event_return);
+                       goto register_error;
+               }
+               /* Take 2 refs on the module: one per event. */
+               ret = try_module_get(event->desc->owner);
+               WARN_ON_ONCE(!ret);
+               ret = try_module_get(event->desc->owner);
+               WARN_ON_ONCE(!ret);
+               ret = _ltt_event_metadata_statedump(chan->session, chan,
+                                                   event_return);
+               if (ret) {
+                       kmem_cache_free(event_cache, event_return);
+                       module_put(event->desc->owner);
+                       module_put(event->desc->owner);
+                       goto statedump_error;
+               }
+               list_add(&event_return->list, &chan->session->events);
+               break;
+       }
        case LTTNG_KERNEL_FUNCTION:
                ret = lttng_ftrace_register(event_param->name,
                                event_param->u.ftrace.symbol_name,
@@ -318,6 +366,11 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan,
                ret = try_module_get(event->desc->owner);
                WARN_ON_ONCE(!ret);
                break;
+       case LTTNG_KERNEL_NOOP:
+               event->desc = internal_desc;
+               if (!event->desc)
+                       goto register_error;
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -329,10 +382,7 @@ struct ltt_event *ltt_event_create(struct ltt_channel *chan,
        return event;
 
 statedump_error:
-       WARN_ON_ONCE(tracepoint_probe_unregister(event_param->name,
-                               event->desc->probe_callback,
-                               event));
-       ltt_event_put(event->desc);
+       /* If a statedump error occurs, events will not be readable. */
 register_error:
        kmem_cache_free(event_cache, event);
 cache_error:
@@ -361,10 +411,17 @@ int _ltt_event_unregister(struct ltt_event *event)
                lttng_kprobes_unregister(event);
                ret = 0;
                break;
+       case LTTNG_KERNEL_KRETPROBE:
+               lttng_kretprobes_unregister(event);
+               ret = 0;
+               break;
        case LTTNG_KERNEL_FUNCTION:
                lttng_ftrace_unregister(event);
                ret = 0;
                break;
+       case LTTNG_KERNEL_NOOP:
+               ret = 0;
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -385,10 +442,16 @@ void _ltt_event_destroy(struct ltt_event *event)
                module_put(event->desc->owner);
                lttng_kprobes_destroy_private(event);
                break;
+       case LTTNG_KERNEL_KRETPROBE:
+               module_put(event->desc->owner);
+               lttng_kretprobes_destroy_private(event);
+               break;
        case LTTNG_KERNEL_FUNCTION:
                module_put(event->desc->owner);
                lttng_ftrace_destroy_private(event);
                break;
+       case LTTNG_KERNEL_NOOP:
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -436,7 +499,7 @@ int lttng_metadata_printf(struct ltt_session *session,
                 * we need to bail out after timeout or being
                 * interrupted.
                 */
-               waitret = wait_event_interruptible_timeout(*chan->ops->get_reader_wait_queue(chan->chan),
+               waitret = wait_event_interruptible_timeout(*chan->ops->get_writer_buf_wait_queue(chan->chan, -1),
                        ({
                                ret = chan->ops->event_reserve(&ctx, 0);
                                ret != -ENOBUFS || !ret;
@@ -467,7 +530,7 @@ int _ltt_field_statedump(struct ltt_session *session,
        switch (field->type.atype) {
        case atype_integer:
                ret = lttng_metadata_printf(session,
-                       "               integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s;\n",
+                       "               integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
                        field->type.u.basic.integer.size,
                        field->type.u.basic.integer.alignment,
                        field->type.u.basic.integer.signedness,
@@ -486,7 +549,7 @@ int _ltt_field_statedump(struct ltt_session *session,
                break;
        case atype_enum:
                ret = lttng_metadata_printf(session,
-                       "               %s %s;\n",
+                       "               %s _%s;\n",
                        field->type.u.basic.enumeration.name,
                        field->name);
                break;
@@ -496,7 +559,7 @@ int _ltt_field_statedump(struct ltt_session *session,
 
                elem_type = &field->type.u.array.elem_type;
                ret = lttng_metadata_printf(session,
-                       "               integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[%u];\n",
+                       "               integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
                        elem_type->u.basic.integer.size,
                        elem_type->u.basic.integer.alignment,
                        elem_type->u.basic.integer.signedness,
@@ -542,7 +605,7 @@ int _ltt_field_statedump(struct ltt_session *session,
                        return ret;
 
                ret = lttng_metadata_printf(session,
-                       "               integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[ __%s_length ];\n",
+                       "               integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
                        elem_type->u.basic.integer.size,
                        (unsigned int) elem_type->u.basic.integer.alignment,
                        elem_type->u.basic.integer.signedness,
@@ -565,7 +628,7 @@ int _ltt_field_statedump(struct ltt_session *session,
        case atype_string:
                /* Default encoding is UTF8 */
                ret = lttng_metadata_printf(session,
-                       "               string%s %s;\n",
+                       "               string%s _%s;\n",
                        field->type.u.basic.string.encoding == lttng_encode_ASCII ?
                                " { encoding = ASCII; }" : "",
                        field->name);
@@ -918,7 +981,7 @@ static int __init ltt_events_init(void)
        event_cache = KMEM_CACHE(ltt_event, 0);
        if (!event_cache)
                return -ENOMEM;
-       ret = ltt_debugfs_abi_init();
+       ret = lttng_abi_init();
        if (ret)
                goto error_abi;
        return 0;
@@ -933,7 +996,7 @@ static void __exit ltt_events_exit(void)
 {
        struct ltt_session *session, *tmpsession;
 
-       ltt_debugfs_abi_exit();
+       lttng_abi_exit();
        list_for_each_entry_safe(session, tmpsession, &sessions, list)
                ltt_session_destroy(session);
        kmem_cache_destroy(event_cache);