Implement capturing payload on event notifier

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

diff --git a/src/lttng-events.c b/src/lttng-events.c
index 9b78ac56f5d43b0fcae0e3d60a38c18965419d04..75a193045b1d381a3bf531542e763d741b095d8a 100644 (file)
--- a/src/lttng-events.c
+++ b/src/lttng-events.c
@@ -1048,11 +1048,13 @@ struct lttng_event_notifier *_lttng_event_notifier_create(
 
        event_notifier->group = event_notifier_group;
        event_notifier->user_token = token;
+       event_notifier->num_captures = 0;
        event_notifier->filter = filter;
        event_notifier->instrumentation = itype;
        event_notifier->evtype = LTTNG_TYPE_EVENT;
        event_notifier->send_notification = lttng_event_notifier_notification_send;
        INIT_LIST_HEAD(&event_notifier->filter_bytecode_runtime_head);
+       INIT_LIST_HEAD(&event_notifier->capture_bytecode_runtime_head);
        INIT_LIST_HEAD(&event_notifier->enablers_ref_head);
 
        switch (itype) {
@@ -2120,6 +2122,13 @@ int lttng_event_notifier_enabler_ref_event_notifiers(
                lttng_enabler_link_bytecode(event_notifier->desc,
                        lttng_static_ctx, &event_notifier->filter_bytecode_runtime_head,
                        &lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->filter_bytecode_head);
+
+               /* Link capture bytecodes if not linked yet. */
+               lttng_enabler_link_bytecode(event_notifier->desc,
+                       lttng_static_ctx, &event_notifier->capture_bytecode_runtime_head,
+                       &event_notifier_enabler->capture_bytecode_head);
+
+               event_notifier->num_captures = event_notifier_enabler->num_captures;
        }
        return 0;
 }
@@ -2318,6 +2327,9 @@ struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
 
        event_notifier_enabler->base.format_type = format_type;
        INIT_LIST_HEAD(&event_notifier_enabler->base.filter_bytecode_head);
+       INIT_LIST_HEAD(&event_notifier_enabler->capture_bytecode_head);
+
+       event_notifier_enabler->num_captures = 0;
 
        memcpy(&event_notifier_enabler->base.event_param, &event_notifier_param->event,
                sizeof(event_notifier_enabler->base.event_param));
@@ -2375,6 +2387,48 @@ error:
        return ret;
 }
 
+int lttng_event_notifier_enabler_attach_capture_bytecode(
+               struct lttng_event_notifier_enabler *event_notifier_enabler,
+               struct lttng_kernel_capture_bytecode __user *bytecode)
+{
+       struct lttng_bytecode_node *bytecode_node;
+       struct lttng_enabler *enabler =
+                       lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
+       uint32_t bytecode_len;
+       int ret;
+
+       ret = get_user(bytecode_len, &bytecode->len);
+       if (ret)
+               return ret;
+
+       bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
+                       GFP_KERNEL);
+       if (!bytecode_node)
+               return -ENOMEM;
+
+       ret = copy_from_user(&bytecode_node->bc, bytecode,
+               sizeof(*bytecode) + bytecode_len);
+       if (ret)
+               goto error_free;
+
+       bytecode_node->type = LTTNG_BYTECODE_NODE_TYPE_CAPTURE;
+       bytecode_node->enabler = enabler;
+
+       /* Enforce length based on allocated size */
+       bytecode_node->bc.len = bytecode_len;
+       list_add_tail(&bytecode_node->node, &event_notifier_enabler->capture_bytecode_head);
+
+       event_notifier_enabler->num_captures++;
+
+       lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
+       goto end;
+
+error_free:
+       lttng_kvfree(bytecode_node);
+end:
+       return ret;
+}
+
 int lttng_event_notifier_add_callsite(struct lttng_event_notifier *event_notifier,
                struct lttng_kernel_event_callsite __user *callsite)
 {
@@ -2565,6 +2619,11 @@ void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group
                list_for_each_entry(runtime,
                                &event_notifier->filter_bytecode_runtime_head, node)
                        lttng_bytecode_filter_sync_state(runtime);
+
+               /* Enable captures */
+               list_for_each_entry(runtime,
+                               &event_notifier->capture_bytecode_runtime_head, node)
+                       lttng_bytecode_capture_sync_state(runtime);
        }
 }