Introduce LTTNG_KERNEL_SESSION_SET_CREATION_TIME

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

diff --git a/lttng-events.c b/lttng-events.c
index 48e1760174569e449a330c766a7c3fca3ecba206..25c616ee82a8aecdc017695036c57445635d0e63 100644 (file)
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -76,7 +76,12 @@ int _lttng_field_statedump(struct lttng_session *session,
 
 void synchronize_trace(void)
 {
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,1,0))
+       synchronize_rcu();
+#else
        synchronize_sched();
+#endif
+
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
 #ifdef CONFIG_PREEMPT_RT_FULL
        synchronize_rcu();
@@ -395,6 +400,7 @@ int lttng_event_enable(struct lttng_event *event)
                break;
        case LTTNG_KERNEL_KPROBE:
        case LTTNG_KERNEL_FUNCTION:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_NOOP:
                WRITE_ONCE(event->enabled, 1);
                break;
@@ -430,6 +436,7 @@ int lttng_event_disable(struct lttng_event *event)
                break;
        case LTTNG_KERNEL_KPROBE:
        case LTTNG_KERNEL_FUNCTION:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_NOOP:
                WRITE_ONCE(event->enabled, 0);
                break;
@@ -576,6 +583,7 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                event_name = event_desc->name;
                break;
        case LTTNG_KERNEL_KPROBE:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_KRETPROBE:
        case LTTNG_KERNEL_FUNCTION:
        case LTTNG_KERNEL_NOOP:
@@ -739,6 +747,28 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
                        goto register_error;
                }
                break;
+       case LTTNG_KERNEL_UPROBE:
+               /*
+                * Needs to be explicitly enabled after creation, since
+                * we may want to apply filters.
+                */
+               event->enabled = 0;
+               event->registered = 1;
+
+               /*
+                * Populate lttng_event structure before event
+                * registration.
+                */
+               smp_wmb();
+
+               ret = lttng_uprobes_register(event_param->name,
+                               event_param->u.uprobe.fd,
+                               event);
+               if (ret)
+                       goto register_error;
+               ret = try_module_get(event->desc->owner);
+               WARN_ON_ONCE(!ret);
+               break;
        default:
                WARN_ON_ONCE(1);
                ret = -EINVAL;
@@ -801,6 +831,7 @@ void register_event(struct lttng_event *event)
                        desc->name);
                break;
        case LTTNG_KERNEL_KPROBE:
+       case LTTNG_KERNEL_UPROBE:
        case LTTNG_KERNEL_KRETPROBE:
        case LTTNG_KERNEL_FUNCTION:
        case LTTNG_KERNEL_NOOP:
@@ -850,6 +881,10 @@ int _lttng_event_unregister(struct lttng_event *event)
        case LTTNG_KERNEL_NOOP:
                ret = 0;
                break;
+       case LTTNG_KERNEL_UPROBE:
+               lttng_uprobes_unregister(event);
+               ret = 0;
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -883,6 +918,10 @@ void _lttng_event_destroy(struct lttng_event *event)
        case LTTNG_KERNEL_NOOP:
        case LTTNG_KERNEL_SYSCALL:
                break;
+       case LTTNG_KERNEL_UPROBE:
+               module_put(event->desc->owner);
+               lttng_uprobes_destroy_private(event);
+               break;
        default:
                WARN_ON_ONCE(1);
        }
@@ -1102,8 +1141,8 @@ int lttng_session_list_tracker_pids(struct lttng_session *session)
                ret = PTR_ERR(tracker_pids_list_file);
                goto file_error;
        }
-       if (atomic_long_add_unless(&session->file->f_count,
-               1, INT_MAX) == INT_MAX) {
+       if (!atomic_long_add_unless(&session->file->f_count, 1, LONG_MAX)) {
+               ret = -EOVERFLOW;
                goto refcount_error;
        }
        ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file);
@@ -1432,6 +1471,18 @@ error_free:
        return ret;
 }
 
+int lttng_event_add_callsite(struct lttng_event *event,
+               struct lttng_kernel_event_callsite __user *callsite)
+{
+
+       switch (event->instrumentation) {
+       case LTTNG_KERNEL_UPROBE:
+               return lttng_uprobes_add_callsite(event, callsite);
+       default:
+               return -EINVAL;
+       }
+}
+
 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
                struct lttng_kernel_context *context_param)
 {
@@ -2428,6 +2479,61 @@ int64_t measure_clock_offset(void)
        return offset;
 }
 
+static
+int print_escaped_ctf_string(struct lttng_session *session, const char *string)
+{
+       int ret;
+       size_t i;
+       char cur;
+
+       i = 0;
+       cur = string[i];
+       while (cur != '\0') {
+               switch (cur) {
+               case '\n':
+                       ret = lttng_metadata_printf(session, "%s", "\\n");
+                       break;
+               case '\\':
+               case '"':
+                       ret = lttng_metadata_printf(session, "%c", '\\');
+                       if (ret)
+                               goto error;
+                       /* We still print the current char */
+                       /* Fallthrough */
+               default:
+                       ret = lttng_metadata_printf(session, "%c", cur);
+                       break;
+               }
+
+               if (ret)
+                       goto error;
+
+               cur = string[++i];
+       }
+error:
+       return ret;
+}
+
+static
+int print_metadata_escaped_field(struct lttng_session *session, const char *field,
+               const char *field_value)
+{
+       int ret;
+
+       ret = lttng_metadata_printf(session, "  %s = \"", field);
+       if (ret)
+               goto error;
+
+       ret = print_escaped_ctf_string(session, field_value);
+       if (ret)
+               goto error;
+
+       ret = lttng_metadata_printf(session, "\";\n");
+
+error:
+       return ret;
+}
+
 /*
  * Output metadata into this session's metadata buffers.
  * Must be called with sessions_mutex held.
@@ -2503,7 +2609,7 @@ int _lttng_session_metadata_statedump(struct lttng_session *session)
                "       tracer_major = %d;\n"
                "       tracer_minor = %d;\n"
                "       tracer_patchlevel = %d;\n"
-               "};\n\n",
+               "       trace_buffering_scheme = \"global\";\n",
                current->nsproxy->uts_ns->name.nodename,
                utsname()->sysname,
                utsname()->release,
@@ -2515,6 +2621,19 @@ int _lttng_session_metadata_statedump(struct lttng_session *session)
        if (ret)
                goto end;
 
+       ret = print_metadata_escaped_field(session, "trace_name", session->name);
+       if (ret)
+               goto end;
+       ret = print_metadata_escaped_field(session, "trace_creation_datetime",
+                       session->creation_time);
+       if (ret)
+               goto end;
+
+       /* Close env */
+       ret = lttng_metadata_printf(session, "};\n\n");
+       if (ret)
+               goto end;
+
        ret = lttng_metadata_printf(session,
                "clock {\n"
                "       name = \"%s\";\n",