X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=lttng-events.c;h=ffb605106ab6f775f467a7409f507947a1cdbc95;hb=4edd719c79048fdc30c5fa9238225f390ff7ad5a;hp=f4337397c1e83ab4dcd788e7d9ae43de48f82272;hpb=c74b9c6f7641042f907ad527f92c2f4155940e8c;p=lttng-modules.git

diff --git a/lttng-events.c b/lttng-events.c
index f4337397..ffb60510 100644
--- a/lttng-events.c
+++ b/lttng-events.c
@@ -329,8 +329,23 @@ int lttng_event_enable(struct lttng_event *event)
 		ret = -EEXIST;
 		goto end;
 	}
-	ACCESS_ONCE(event->enabled) = 1;
-	lttng_session_sync_enablers(event->chan->session);
+	switch (event->instrumentation) {
+	case LTTNG_KERNEL_TRACEPOINT:
+	case LTTNG_KERNEL_SYSCALL:
+		ret = -EINVAL;
+		break;
+	case LTTNG_KERNEL_KPROBE:
+	case LTTNG_KERNEL_FUNCTION:
+	case LTTNG_KERNEL_NOOP:
+		ACCESS_ONCE(event->enabled) = 1;
+		break;
+	case LTTNG_KERNEL_KRETPROBE:
+		ret = lttng_kretprobes_event_enable_state(event, 1);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		ret = -EINVAL;
+	}
 end:
 	mutex_unlock(&sessions_mutex);
 	return ret;
@@ -349,8 +364,23 @@ int lttng_event_disable(struct lttng_event *event)
 		ret = -EEXIST;
 		goto end;
 	}
-	ACCESS_ONCE(event->enabled) = 0;
-	lttng_session_sync_enablers(event->chan->session);
+	switch (event->instrumentation) {
+	case LTTNG_KERNEL_TRACEPOINT:
+	case LTTNG_KERNEL_SYSCALL:
+		ret = -EINVAL;
+		break;
+	case LTTNG_KERNEL_KPROBE:
+	case LTTNG_KERNEL_FUNCTION:
+	case LTTNG_KERNEL_NOOP:
+		ACCESS_ONCE(event->enabled) = 0;
+		break;
+	case LTTNG_KERNEL_KRETPROBE:
+		ret = lttng_kretprobes_event_enable_state(event, 0);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		ret = -EINVAL;
+	}
 end:
 	mutex_unlock(&sessions_mutex);
 	return ret;
@@ -538,7 +568,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 		smp_wmb();
 		break;
 	case LTTNG_KERNEL_KPROBE:
-		event->enabled = 1;
+		/*
+		 * 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
@@ -562,7 +596,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 		struct lttng_event *event_return;
 
 		/* kretprobe defines 2 events */
-		event->enabled = 1;
+		/*
+		 * Needs to be explicitly enabled after creation, since
+		 * we may want to apply filters.
+		 */
+		event->enabled = 0;
 		event->registered = 1;
 		event_return =
 			kmem_cache_zalloc(event_cache, GFP_KERNEL);
@@ -573,7 +611,7 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 		event_return->chan = chan;
 		event_return->filter = filter;
 		event_return->id = chan->free_event_id++;
-		event_return->enabled = 1;
+		event_return->enabled = 0;
 		event_return->registered = 1;
 		event_return->instrumentation = itype;
 		/*
@@ -608,7 +646,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 		break;
 	}
 	case LTTNG_KERNEL_FUNCTION:
-		event->enabled = 1;
+		/*
+		 * 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
@@ -626,7 +668,11 @@ struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 		break;
 	case LTTNG_KERNEL_NOOP:
 	case LTTNG_KERNEL_SYSCALL:
-		event->enabled = 1;
+		/*
+		 * Needs to be explicitly enabled after creation, since
+		 * we may want to apply filters.
+		 */
+		event->enabled = 0;
 		event->registered = 0;
 		event->desc = event_desc;
 		if (!event->desc) {
@@ -997,17 +1043,22 @@ 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) {
+		goto refcount_error;
+	}
 	ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file);
 	if (ret < 0)
 		goto open_error;
 	m = tracker_pids_list_file->private_data;
 	m->private = session;
 	fd_install(file_fd, tracker_pids_list_file);
-	atomic_long_inc(&session->file->f_count);
 
 	return file_fd;
 
 open_error:
+	atomic_long_dec(&session->file->f_count);
+refcount_error:
 	fput(tracker_pids_list_file);
 file_error:
 	put_unused_fd(file_fd);
@@ -1909,11 +1960,14 @@ int _lttng_event_header_declare(struct lttng_session *session)
  * taken at start of trace.
  * Yes, this is only an approximation. Yes, we can (and will) do better
  * in future versions.
+ * Return 0 if offset is negative. It may happen if the system sets
+ * the REALTIME clock to 0 after boot.
  */
 static
 uint64_t measure_clock_offset(void)
 {
-	uint64_t offset, monotonic[2], realtime;
+	uint64_t monotonic_avg, monotonic[2], realtime;
+	int64_t offset;
 	struct timespec rts = { 0, 0 };
 	unsigned long flags;
 
@@ -1924,10 +1978,12 @@ uint64_t measure_clock_offset(void)
 	monotonic[1] = trace_clock_read64();
 	local_irq_restore(flags);
 
-	offset = (monotonic[0] + monotonic[1]) >> 1;
+	monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
 	realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC;
 	realtime += rts.tv_nsec;
-	offset = realtime - offset;
+	offset = (int64_t) realtime - monotonic_avg;
+	if (offset < 0)
+		return 0;
 	return offset;
 }
 
@@ -2139,6 +2195,9 @@ static int __init lttng_events_init(void)
 	if (ret)
 		return ret;
 	ret = wrapper_get_pfnblock_flags_mask_init();
+	if (ret)
+		return ret;
+	ret = wrapper_get_pageblock_flags_mask_init();
 	if (ret)
 		return ret;
 	ret = lttng_context_init();