Fix RCU-related hangs: incorrect lttng_ht_destroy use

[lttng-tools.git] / src / bin / lttng-sessiond / trace-kernel.c

diff --git a/src/bin/lttng-sessiond/trace-kernel.c b/src/bin/lttng-sessiond/trace-kernel.c
index 7748b891faef7b35add6d9c6e8e2da2e52f24f96..d889b6ab6582570587c9c4a66cdcf51fad30943a 100644 (file)
--- a/src/bin/lttng-sessiond/trace-kernel.c
+++ b/src/bin/lttng-sessiond/trace-kernel.c
@@ -35,10 +35,8 @@ struct ltt_kernel_channel *trace_kernel_get_channel_by_name(
 {
        struct ltt_kernel_channel *chan;
 
-       if (session == NULL) {
-               ERR("Undefine session");
-               goto error;
-       }
+       assert(session);
+       assert(name);
 
        DBG("Trying to find channel %s", name);
 
@@ -49,7 +47,6 @@ struct ltt_kernel_channel *trace_kernel_get_channel_by_name(
                }
        }
 
-error:
        return NULL;
 }
 
@@ -61,10 +58,8 @@ struct ltt_kernel_event *trace_kernel_get_event_by_name(
 {
        struct ltt_kernel_event *ev;
 
-       if (channel == NULL) {
-               ERR("Undefine channel");
-               goto error;
-       }
+       assert(name);
+       assert(channel);
 
        cds_list_for_each_entry(ev, &channel->events_list.head, list) {
                if (strcmp(name, ev->event->name) == 0) {
@@ -74,7 +69,6 @@ struct ltt_kernel_event *trace_kernel_get_event_by_name(
                }
        }
 
-error:
        return NULL;
 }
 
@@ -83,9 +77,8 @@ error:
  *
  * Return pointer to structure or NULL.
  */
-struct ltt_kernel_session *trace_kernel_create_session(char *path)
+struct ltt_kernel_session *trace_kernel_create_session(void)
 {
-       int ret;
        struct ltt_kernel_session *lks = NULL;
 
        /* Allocate a new ltt kernel session */
@@ -116,23 +109,6 @@ struct ltt_kernel_session *trace_kernel_create_session(char *path)
         */
        lks->tmp_consumer = NULL;
 
-       if (path && strlen(path) > 0) {
-               /* Use the default consumer output which is the tracing session path. */
-               ret = snprintf(lks->consumer->dst.trace_path, PATH_MAX,
-                               "%s" DEFAULT_KERNEL_TRACE_DIR, path);
-               if (ret < 0) {
-                       PERROR("snprintf consumer trace path");
-                       goto error;
-               }
-
-               /* Set session path */
-               ret = asprintf(&lks->trace_path, "%s" DEFAULT_KERNEL_TRACE_DIR, path);
-               if (ret < 0) {
-                       PERROR("asprintf kernel traces path");
-                       goto error;
-               }
-       }
-
        return lks;
 
 error:
@@ -148,10 +124,12 @@ alloc_error:
  * Return pointer to structure or NULL.
  */
 struct ltt_kernel_channel *trace_kernel_create_channel(
-               struct lttng_channel *chan, char *path)
+               struct lttng_channel *chan)
 {
        struct ltt_kernel_channel *lkc;
 
+       assert(chan);
+
        lkc = zmalloc(sizeof(struct ltt_kernel_channel));
        if (lkc == NULL) {
                PERROR("ltt_kernel_channel zmalloc");
@@ -161,6 +139,7 @@ struct ltt_kernel_channel *trace_kernel_create_channel(
        lkc->channel = zmalloc(sizeof(struct lttng_channel));
        if (lkc->channel == NULL) {
                PERROR("lttng_channel zmalloc");
+               free(lkc);
                goto error;
        }
        memcpy(lkc->channel, chan, sizeof(struct lttng_channel));
@@ -190,6 +169,8 @@ struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev)
        struct ltt_kernel_event *lke;
        struct lttng_kernel_event *attr;
 
+       assert(ev);
+
        lke = zmalloc(sizeof(struct ltt_kernel_event));
        attr = zmalloc(sizeof(struct lttng_kernel_event));
        if (lke == NULL || attr == NULL) {
@@ -243,7 +224,6 @@ struct ltt_kernel_event *trace_kernel_create_event(struct lttng_event *ev)
        lke->fd = -1;
        lke->event = attr;
        lke->enabled = 1;
-       lke->ctx = NULL;
 
        return lke;
 
@@ -272,10 +252,10 @@ struct ltt_kernel_metadata *trace_kernel_create_metadata(void)
 
        /* Set default attributes */
        chan->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
-       chan->attr.subbuf_size = DEFAULT_METADATA_SUBBUF_SIZE;
+       chan->attr.subbuf_size = default_get_metadata_subbuf_size();
        chan->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
-       chan->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
-       chan->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
+       chan->attr.switch_timer_interval = DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER;
+       chan->attr.read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER;
        chan->attr.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
 
        /* Init metadata */
@@ -302,6 +282,8 @@ struct ltt_kernel_stream *trace_kernel_create_stream(const char *name,
        int ret;
        struct ltt_kernel_stream *lks;
 
+       assert(name);
+
        lks = zmalloc(sizeof(struct ltt_kernel_stream));
        if (lks == NULL) {
                PERROR("kernel stream zmalloc");
@@ -319,6 +301,7 @@ struct ltt_kernel_stream *trace_kernel_create_stream(const char *name,
        /* Init stream */
        lks->fd = -1;
        lks->state = 0;
+       lks->cpu = count;
 
        return lks;
 
@@ -331,11 +314,13 @@ error:
  */
 void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream)
 {
-       int ret;
+       assert(stream);
 
        DBG("[trace] Closing stream fd %d", stream->fd);
        /* Close kernel fd */
        if (stream->fd >= 0) {
+               int ret;
+
                ret = close(stream->fd);
                if (ret) {
                        PERROR("close");
@@ -352,9 +337,11 @@ void trace_kernel_destroy_stream(struct ltt_kernel_stream *stream)
  */
 void trace_kernel_destroy_event(struct ltt_kernel_event *event)
 {
-       int ret;
+       assert(event);
 
        if (event->fd >= 0) {
+               int ret;
+
                DBG("[trace] Closing event fd %d", event->fd);
                /* Close kernel fd */
                ret = close(event->fd);
@@ -369,7 +356,6 @@ void trace_kernel_destroy_event(struct ltt_kernel_event *event)
        cds_list_del(&event->list);
 
        free(event->event);
-       free(event->ctx);
        free(event);
 }
 
@@ -382,6 +368,8 @@ void trace_kernel_destroy_channel(struct ltt_kernel_channel *channel)
        struct ltt_kernel_event *event, *etmp;
        int ret;
 
+       assert(channel);
+
        DBG("[trace] Closing channel fd %d", channel->fd);
        /* Close kernel fd */
        if (channel->fd >= 0) {
@@ -414,11 +402,13 @@ void trace_kernel_destroy_channel(struct ltt_kernel_channel *channel)
  */
 void trace_kernel_destroy_metadata(struct ltt_kernel_metadata *metadata)
 {
-       int ret;
+       assert(metadata);
 
        DBG("[trace] Closing metadata fd %d", metadata->fd);
        /* Close kernel fd */
        if (metadata->fd >= 0) {
+               int ret;
+
                ret = close(metadata->fd);
                if (ret) {
                        PERROR("close");
@@ -431,12 +421,16 @@ void trace_kernel_destroy_metadata(struct ltt_kernel_metadata *metadata)
 
 /*
  * Cleanup kernel session structure
+ *
+ * Should *NOT* be called with RCU read-side lock held.
  */
 void trace_kernel_destroy_session(struct ltt_kernel_session *session)
 {
        struct ltt_kernel_channel *channel, *ctmp;
        int ret;
 
+       assert(session);
+
        DBG("[trace] Closing session fd %d", session->fd);
        /* Close kernel fds */
        if (session->fd >= 0) {
@@ -466,6 +460,5 @@ void trace_kernel_destroy_session(struct ltt_kernel_session *session)
        consumer_destroy_output(session->consumer);
        consumer_destroy_output(session->tmp_consumer);
 
-       free(session->trace_path);
        free(session);
 }