X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;ds=sidebyside;f=src%2Fbin%2Flttng-sessiond%2Fkernel.c;h=32c40531d21b3e50f4d7b1851594b2ad1090ea4f;hb=0525e9ae15d215943d8187e7f190d5a45e723085;hp=00172e80170c3089a9160bcd49ce8d72357107c0;hpb=601d5acf42ebdb05ff8aa19f12fd9bdad3602781;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c
index 00172e801..32c40531d 100644
--- a/src/bin/lttng-sessiond/kernel.c
+++ b/src/bin/lttng-sessiond/kernel.c
@@ -40,6 +40,9 @@ int kernel_add_channel_context(struct ltt_kernel_channel *chan,
 {
 	int ret;
 
+	assert(chan);
+	assert(ctx);
+
 	DBG("Adding context to channel %s", chan->channel->name);
 	ret = kernctl_add_context(chan->fd, ctx);
 	if (ret < 0) {
@@ -75,6 +78,8 @@ int kernel_create_session(struct ltt_session *session, int tracer_fd)
 	int ret;
 	struct ltt_kernel_session *lks;
 
+	assert(session);
+
 	/* Allocate data structure */
 	lks = trace_kernel_create_session(session->path);
 	if (lks == NULL) {
@@ -118,6 +123,10 @@ int kernel_create_channel(struct ltt_kernel_session *session,
 	int ret;
 	struct ltt_kernel_channel *lkc;
 
+	assert(session);
+	assert(chan);
+	assert(path);
+
 	/* Allocate kernel channel */
 	lkc = trace_kernel_create_channel(chan, path);
 	if (lkc == NULL) {
@@ -148,6 +157,7 @@ int kernel_create_channel(struct ltt_kernel_session *session,
 	/* Add channel to session */
 	cds_list_add(&lkc->list, &session->channel_list.head);
 	session->channel_count++;
+	lkc->session = session;
 
 	DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd);
 
@@ -167,6 +177,9 @@ int kernel_create_event(struct lttng_event *ev,
 	int ret;
 	struct ltt_kernel_event *event;
 
+	assert(ev);
+	assert(channel);
+
 	event = trace_kernel_create_event(ev);
 	if (event == NULL) {
 		ret = -1;
@@ -230,6 +243,8 @@ int kernel_disable_channel(struct ltt_kernel_channel *chan)
 {
 	int ret;
 
+	assert(chan);
+
 	ret = kernctl_disable(chan->fd);
 	if (ret < 0) {
 		PERROR("disable chan ioctl");
@@ -253,6 +268,8 @@ int kernel_enable_channel(struct ltt_kernel_channel *chan)
 {
 	int ret;
 
+	assert(chan);
+
 	ret = kernctl_enable(chan->fd);
 	if (ret < 0 && errno != EEXIST) {
 		PERROR("Enable kernel chan");
@@ -275,6 +292,8 @@ int kernel_enable_event(struct ltt_kernel_event *event)
 {
 	int ret;
 
+	assert(event);
+
 	ret = kernctl_enable(event->fd);
 	if (ret < 0) {
 		switch (errno) {
@@ -304,6 +323,8 @@ int kernel_disable_event(struct ltt_kernel_event *event)
 {
 	int ret;
 
+	assert(event);
+
 	ret = kernctl_disable(event->fd);
 	if (ret < 0) {
 		switch (errno) {
@@ -335,6 +356,8 @@ int kernel_open_metadata(struct ltt_kernel_session *session)
 	int ret;
 	struct ltt_kernel_metadata *lkm;
 
+	assert(session);
+
 	/* Allocate kernel metadata */
 	lkm = trace_kernel_create_metadata();
 	if (lkm == NULL) {
@@ -371,6 +394,8 @@ int kernel_start_session(struct ltt_kernel_session *session)
 {
 	int ret;
 
+	assert(session);
+
 	ret = kernctl_start_session(session->fd);
 	if (ret < 0) {
 		PERROR("ioctl start session");
@@ -408,6 +433,8 @@ int kernel_calibrate(int fd, struct lttng_kernel_calibrate *calibrate)
 {
 	int ret;
 
+	assert(calibrate);
+
 	ret = kernctl_calibrate(fd, calibrate);
 	if (ret < 0) {
 		PERROR("calibrate ioctl");
@@ -441,6 +468,8 @@ int kernel_flush_buffer(struct ltt_kernel_channel *channel)
 	int ret;
 	struct ltt_kernel_stream *stream;
 
+	assert(channel);
+
 	DBG("Flush buffer for channel %s", channel->channel->name);
 
 	cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
@@ -463,6 +492,8 @@ int kernel_stop_session(struct ltt_kernel_session *session)
 {
 	int ret;
 
+	assert(session);
+
 	ret = kernctl_stop_session(session->fd);
 	if (ret < 0) {
 		goto error;
@@ -487,6 +518,8 @@ int kernel_open_channel_stream(struct ltt_kernel_channel *channel)
 	int ret, count = 0;
 	struct ltt_kernel_stream *lks;
 
+	assert(channel);
+
 	while ((ret = kernctl_create_stream(channel->fd)) >= 0) {
 		lks = trace_kernel_create_stream(channel->channel->name, count);
 		if (lks == NULL) {
@@ -528,6 +561,8 @@ int kernel_open_metadata_stream(struct ltt_kernel_session *session)
 {
 	int ret;
 
+	assert(session);
+
 	ret = kernctl_create_stream(session->metadata->fd);
 	if (ret < 0) {
 		PERROR("kernel create metadata stream");
@@ -556,10 +591,11 @@ ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events)
 	int fd, pos, ret;
 	char *event;
 	size_t nbmem, count = 0;
-	ssize_t size;
 	FILE *fp;
 	struct lttng_event *elist;
 
+	assert(events);
+
 	fd = kernctl_tracepoint_list(tracer_fd);
 	if (fd < 0) {
 		PERROR("kernel tracepoint list");
@@ -584,7 +620,7 @@ ssize_t kernel_list_events(int tracer_fd, struct lttng_event **events)
 		goto end;
 	}
 
-	while ((size = fscanf(fp, "event { name = %m[^;]; };%n\n", &event, &pos)) == 1) {
+	while (fscanf(fp, "event { name = %m[^;]; };%n\n", &event, &pos) == 1) {
 		if (count >= nbmem) {
 			struct lttng_event *new_elist;
 
@@ -709,3 +745,33 @@ void kernel_destroy_session(struct ltt_kernel_session *ksess)
 
 	trace_kernel_destroy_session(ksess);
 }
+
+/*
+ * Destroy a kernel channel object. It does not do anything on the tracer side.
+ */
+void kernel_destroy_channel(struct ltt_kernel_channel *kchan)
+{
+	struct ltt_kernel_session *ksess = NULL;
+
+	assert(kchan);
+	assert(kchan->channel);
+
+	DBG3("Kernel destroy channel %s", kchan->channel->name);
+
+	/* Update channel count of associated session. */
+	if (kchan->session) {
+		/* Keep pointer reference so we can update it after the destroy. */
+		ksess = kchan->session;
+	}
+
+	trace_kernel_destroy_channel(kchan);
+
+	/*
+	 * At this point the kernel channel is not visible anymore. This is safe
+	 * since in order to work on a visible kernel session, the tracing session
+	 * lock (ltt_session.lock) MUST be acquired.
+	 */
+	if (ksess) {
+		ksess->channel_count--;
+	}
+}