X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fcmd.c;h=cf30b8ebfbf88feda7cfa84617bf4ff4dae79b25;hb=09a88287202e1cb7bcc984f65237bee33e6c5b93;hp=21422a57deb7c674295f37545ccfba35d1ed2f64;hpb=8ee609c81c5be3880cc48b863227320763733356;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/cmd.c b/src/bin/lttng-sessiond/cmd.c
index 21422a57d..cf30b8ebf 100644
--- a/src/bin/lttng-sessiond/cmd.c
+++ b/src/bin/lttng-sessiond/cmd.c
@@ -41,6 +41,7 @@
 #include "syscall.h"
 #include "agent.h"
 #include "buffer-registry.h"
+#include "agent-thread.h"
 
 #include "cmd.h"
 
@@ -235,11 +236,11 @@ end:
 /*
  * Fill lttng_channel array of all channels.
  */
-static void list_lttng_channels(enum lttng_domain_type domain,
+static ssize_t list_lttng_channels(enum lttng_domain_type domain,
 		struct ltt_session *session, struct lttng_channel *channels,
 		struct lttcomm_channel_extended *chan_exts)
 {
-	int i = 0, ret;
+	int i = 0, ret = 0;
 	struct ltt_kernel_channel *kchan;
 
 	DBG("Listing channels for session %s", session->name);
@@ -325,7 +326,11 @@ static void list_lttng_channels(enum lttng_domain_type domain,
 	}
 
 end:
-	return;
+	if (ret < 0) {
+		return -LTTNG_ERR_FATAL;
+	} else {
+		return LTTNG_OK;
+	}
 }
 
 static void increment_extended_len(const char *filter_expression,
@@ -852,8 +857,11 @@ static int create_connect_relayd(struct lttng_uri *uri,
 
 		/* Check relayd version */
 		ret = relayd_version_check(rsock);
-		if (ret < 0) {
-			ret = LTTNG_ERR_RELAYD_VERSION_FAIL;
+		if (ret == LTTNG_ERR_RELAYD_VERSION_FAIL) {
+			goto close_sock;
+		} else if (ret < 0) {
+			ERR("Unable to reach lttng-relayd");
+			ret = LTTNG_ERR_RELAYD_CONNECT_FAIL;
 			goto close_sock;
 		}
 		consumer->relay_major_version = rsock->major;
@@ -882,6 +890,8 @@ error:
 
 /*
  * Connect to the relayd using URI and send the socket to the right consumer.
+ *
+ * The consumer socket lock must be held by the caller.
  */
 static int send_consumer_relayd_socket(enum lttng_domain_type domain,
 		unsigned int session_id, struct lttng_uri *relayd_uri,
@@ -895,7 +905,7 @@ static int send_consumer_relayd_socket(enum lttng_domain_type domain,
 	/* Connect to relayd and make version check if uri is the control. */
 	ret = create_connect_relayd(relayd_uri, &rsock, consumer);
 	if (ret != LTTNG_OK) {
-		goto error;
+		goto relayd_comm_error;
 	}
 	assert(rsock);
 
@@ -935,10 +945,6 @@ static int send_consumer_relayd_socket(enum lttng_domain_type domain,
 	 */
 
 close_sock:
-	(void) relayd_close(rsock);
-	free(rsock);
-
-error:
 	if (ret != LTTNG_OK) {
 		/*
 		 * The consumer output for this session should not be used anymore
@@ -947,6 +953,10 @@ error:
 		 */
 		consumer->enabled = 0;
 	}
+	(void) relayd_close(rsock);
+	free(rsock);
+
+relayd_comm_error:
 	return ret;
 }
 
@@ -954,6 +964,8 @@ error:
  * Send both relayd sockets to a specific consumer and domain.  This is a
  * helper function to facilitate sending the information to the consumer for a
  * session.
+ *
+ * The consumer socket lock must be held by the caller.
  */
 static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
 		unsigned int session_id, struct consumer_output *consumer,
@@ -1333,14 +1345,19 @@ int cmd_enable_channel(struct ltt_session *session,
 		attr->attr.switch_timer_interval = 0;
 	}
 
-	/*
-	 * The ringbuffer (both in user space and kernel) behave badly in overwrite
-	 * mode and with less than 2 subbuf so block it right away and send back an
-	 * invalid attribute error.
-	 */
-	if (attr->attr.overwrite && attr->attr.num_subbuf < 2) {
-		ret = LTTNG_ERR_INVALID;
-		goto error;
+	/* Check for feature support */
+	switch (domain->type) {
+	case LTTNG_DOMAIN_JUL:
+	case LTTNG_DOMAIN_LOG4J:
+	case LTTNG_DOMAIN_PYTHON:
+		if (!agent_tracing_is_enabled()) {
+			DBG("Attempted to enable a channel in an agent domain but the agent thread is not running");
+			ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
+			goto error;
+		}
+		break;
+	default:
+		break;
 	}
 
 	switch (domain->type) {
@@ -1615,6 +1632,16 @@ int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
 	int ret, chan_kern_created = 0, chan_ust_created = 0;
 	char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
 
+	/*
+	 * Don't try to add a context if the session has been started at
+	 * some point in time before. The tracer does not allow it and would
+	 * result in a corrupted trace.
+	 */
+	if (session->has_been_started) {
+		ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+		goto end;
+	}
+
 	if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
 		app_ctx_provider_name = ctx->u.app_ctx.provider_name;
 		app_ctx_name = ctx->u.app_ctx.ctx_name;
@@ -2066,6 +2093,12 @@ static int _cmd_enable_event(struct ltt_session *session,
 
 		assert(usess);
 
+		if (!agent_tracing_is_enabled()) {
+			DBG("Attempted to enable an event in an agent domain but the agent thread is not running");
+			ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
+			goto error;
+		}
+
 		agt = trace_ust_find_agent(usess, domain->type);
 		if (!agt) {
 			agt = agent_create(domain->type);
@@ -2447,7 +2480,15 @@ int cmd_stop_trace(struct ltt_session *session)
 	if (ksession && ksession->active) {
 		DBG("Stop kernel tracing");
 
-		/* Flush metadata if exist */
+		ret = kernel_stop_session(ksession);
+		if (ret < 0) {
+			ret = LTTNG_ERR_KERN_STOP_FAIL;
+			goto error;
+		}
+
+		kernel_wait_quiescent(kernel_tracer_fd);
+
+		/* Flush metadata after stopping (if exists) */
 		if (ksession->metadata_stream_fd >= 0) {
 			ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
 			if (ret < 0) {
@@ -2455,7 +2496,7 @@ int cmd_stop_trace(struct ltt_session *session)
 			}
 		}
 
-		/* Flush all buffers before stopping */
+		/* Flush all buffers after stopping */
 		cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
 			ret = kernel_flush_buffer(kchan);
 			if (ret < 0) {
@@ -2463,14 +2504,6 @@ int cmd_stop_trace(struct ltt_session *session)
 			}
 		}
 
-		ret = kernel_stop_session(ksession);
-		if (ret < 0) {
-			ret = LTTNG_ERR_KERN_STOP_FAIL;
-			goto error;
-		}
-
-		kernel_wait_quiescent(kernel_tracer_fd);
-
 		ksession->active = 0;
 	}
 
@@ -2758,64 +2791,6 @@ int cmd_destroy_session(struct ltt_session *session, int wpipe)
 	return ret;
 }
 
-/*
- * Command LTTNG_CALIBRATE processed by the client thread.
- */
-int cmd_calibrate(enum lttng_domain_type domain,
-		struct lttng_calibrate *calibrate)
-{
-	int ret;
-
-	switch (domain) {
-	case LTTNG_DOMAIN_KERNEL:
-	{
-		struct lttng_kernel_calibrate kcalibrate;
-
-		switch (calibrate->type) {
-		case LTTNG_CALIBRATE_FUNCTION:
-		default:
-			/* Default and only possible calibrate option. */
-			kcalibrate.type = LTTNG_KERNEL_CALIBRATE_KRETPROBE;
-			break;
-		}
-
-		ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
-		if (ret < 0) {
-			ret = LTTNG_ERR_KERN_ENABLE_FAIL;
-			goto error;
-		}
-		break;
-	}
-	case LTTNG_DOMAIN_UST:
-	{
-		struct lttng_ust_calibrate ucalibrate;
-
-		switch (calibrate->type) {
-		case LTTNG_CALIBRATE_FUNCTION:
-		default:
-			/* Default and only possible calibrate option. */
-			ucalibrate.type = LTTNG_UST_CALIBRATE_TRACEPOINT;
-			break;
-		}
-
-		ret = ust_app_calibrate_glb(&ucalibrate);
-		if (ret < 0) {
-			ret = LTTNG_ERR_UST_CALIBRATE_FAIL;
-			goto error;
-		}
-		break;
-	}
-	default:
-		ret = LTTNG_ERR_UND;
-		goto error;
-	}
-
-	ret = LTTNG_OK;
-
-error:
-	return ret;
-}
-
 /*
  * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
  */
@@ -3020,7 +2995,12 @@ ssize_t cmd_list_channels(enum lttng_domain_type domain,
 
 		channel_exts = ((void *) *channels) +
 				(nb_chan * sizeof(struct lttng_channel));
-		list_lttng_channels(domain, session, *channels, channel_exts);
+		ret = list_lttng_channels(domain, session, *channels, channel_exts);
+		if (ret != LTTNG_OK) {
+			free(*channels);
+			*channels = NULL;
+			goto end;
+		}
 	} else {
 		*channels = NULL;
 	}
@@ -3217,11 +3197,10 @@ int cmd_snapshot_add_output(struct ltt_session *session,
 	DBG("Cmd snapshot add output for session %s", session->name);
 
 	/*
-	 * Permission denied to create an output if the session is not
-	 * set in no output mode.
+	 * Can't create an output if the session is not set in no-output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
 		goto error;
 	}
 
@@ -3285,7 +3264,7 @@ int cmd_snapshot_del_output(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
 		goto error;
 	}
 
@@ -3337,19 +3316,19 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = -LTTNG_ERR_EPERM;
-		goto error;
+		ret = -LTTNG_ERR_NOT_SNAPSHOT_SESSION;
+		goto end;
 	}
 
 	if (session->snapshot.nb_output == 0) {
 		ret = 0;
-		goto error;
+		goto end;
 	}
 
 	list = zmalloc(session->snapshot.nb_output * sizeof(*list));
 	if (!list) {
 		ret = -LTTNG_ERR_NOMEM;
-		goto error;
+		goto end;
 	}
 
 	/* Copy list from session to the new list object. */
@@ -3395,8 +3374,9 @@ ssize_t cmd_snapshot_list_outputs(struct ltt_session *session,
 	list = NULL;
 	ret = session->snapshot.nb_output;
 error:
-	free(list);
 	rcu_read_unlock();
+	free(list);
+end:
 	return ret;
 }
 
@@ -3407,7 +3387,7 @@ error:
  * Return 0 if the metadata can be generated, a LTTNG_ERR code otherwise.
  */
 static
-int check_metadata_regenerate_support(struct ltt_session *session)
+int check_regenerate_metadata_support(struct ltt_session *session)
 {
 	int ret;
 
@@ -3446,7 +3426,30 @@ end:
 }
 
 static
-int ust_metadata_regenerate(struct ltt_ust_session *usess)
+int clear_metadata_file(int fd)
+{
+	int ret;
+	off_t lseek_ret;
+
+	lseek_ret = lseek(fd, 0, SEEK_SET);
+	if (lseek_ret < 0) {
+		PERROR("lseek");
+		ret = -1;
+		goto end;
+	}
+
+	ret = ftruncate(fd, 0);
+	if (ret < 0) {
+		PERROR("ftruncate");
+		goto end;
+	}
+
+end:
+	return ret;
+}
+
+static
+int ust_regenerate_metadata(struct ltt_ust_session *usess)
 {
 	int ret = 0;
 	struct buffer_reg_uid *uid_reg = NULL;
@@ -3466,6 +3469,15 @@ int ust_metadata_regenerate(struct ltt_ust_session *usess)
 		memset(registry->metadata, 0, registry->metadata_alloc_len);
 		registry->metadata_len = 0;
 		registry->metadata_version++;
+		if (registry->metadata_fd > 0) {
+			/* Clear the metadata file's content. */
+			ret = clear_metadata_file(registry->metadata_fd);
+			if (ret) {
+				pthread_mutex_unlock(&registry->lock);
+				goto end;
+			}
+		}
+
 		ret = ust_metadata_session_statedump(registry, NULL,
 				registry->major, registry->minor);
 		if (ret) {
@@ -3507,7 +3519,7 @@ end:
 }
 
 /*
- * Command LTTNG_METADATA_REGENERATE from the lttng-ctl library.
+ * Command LTTNG_REGENERATE_METADATA from the lttng-ctl library.
  *
  * Ask the consumer to truncate the existing metadata file(s) and
  * then regenerate the metadata. Live and per-pid sessions are not
@@ -3515,19 +3527,19 @@ end:
  *
  * Return 0 on success or else a LTTNG_ERR code.
  */
-int cmd_metadata_regenerate(struct ltt_session *session)
+int cmd_regenerate_metadata(struct ltt_session *session)
 {
 	int ret;
 
 	assert(session);
 
-	ret = check_metadata_regenerate_support(session);
+	ret = check_regenerate_metadata_support(session);
 	if (ret) {
 		goto end;
 	}
 
 	if (session->kernel_session) {
-		ret = kernctl_session_metadata_regenerate(
+		ret = kernctl_session_regenerate_metadata(
 				session->kernel_session->fd);
 		if (ret < 0) {
 			ERR("Failed to regenerate the kernel metadata");
@@ -3536,7 +3548,7 @@ int cmd_metadata_regenerate(struct ltt_session *session)
 	}
 
 	if (session->ust_session) {
-		ret = ust_metadata_regenerate(session->ust_session);
+		ret = ust_regenerate_metadata(session->ust_session);
 		if (ret < 0) {
 			ERR("Failed to regenerate the UST metadata");
 			goto end;
@@ -3549,6 +3561,60 @@ end:
 	return ret;
 }
 
+/*
+ * Command LTTNG_REGENERATE_STATEDUMP from the lttng-ctl library.
+ *
+ * Ask the tracer to regenerate a new statedump.
+ *
+ * Return 0 on success or else a LTTNG_ERR code.
+ */
+int cmd_regenerate_statedump(struct ltt_session *session)
+{
+	int ret;
+
+	assert(session);
+
+	if (!session->active) {
+		ret = LTTNG_ERR_SESSION_NOT_STARTED;
+		goto end;
+	}
+	ret = 0;
+
+	if (session->kernel_session) {
+		ret = kernctl_session_regenerate_statedump(
+				session->kernel_session->fd);
+		/*
+		 * Currently, the statedump in kernel can only fail if out
+		 * of memory.
+		 */
+		if (ret < 0) {
+			if (ret == -ENOMEM) {
+				ret = LTTNG_ERR_REGEN_STATEDUMP_NOMEM;
+			} else {
+				ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
+			}
+			ERR("Failed to regenerate the kernel statedump");
+			goto end;
+		}
+	}
+
+	if (session->ust_session) {
+		ret = ust_app_regenerate_statedump_all(session->ust_session);
+		/*
+		 * Currently, the statedump in UST always returns 0.
+		 */
+		if (ret < 0) {
+			ret = LTTNG_ERR_REGEN_STATEDUMP_FAIL;
+			ERR("Failed to regenerate the UST statedump");
+			goto end;
+		}
+	}
+	DBG("Cmd regenerate statedump for session %s", session->name);
+	ret = LTTNG_OK;
+
+end:
+	return ret;
+}
 
 /*
  * Send relayd sockets from snapshot output to consumer. Ignore request if the
@@ -3581,10 +3647,12 @@ static int set_relayd_for_snapshot(struct consumer_output *consumer,
 	rcu_read_lock();
 	cds_lfht_for_each_entry(snap_output->consumer->socks->ht, &iter.iter,
 			socket, node.node) {
+		pthread_mutex_lock(socket->lock);
 		ret = send_consumer_relayd_sockets(0, session->id,
 				snap_output->consumer, socket,
 				session->name, session->hostname,
 				session->live_timer);
+		pthread_mutex_unlock(socket->lock);
 		if (ret != LTTNG_OK) {
 			rcu_read_unlock();
 			goto error;
@@ -3816,7 +3884,7 @@ int cmd_snapshot_record(struct ltt_session *session,
 	 * set in no output mode.
 	 */
 	if (session->output_traces) {
-		ret = LTTNG_ERR_EPERM;
+		ret = LTTNG_ERR_NOT_SNAPSHOT_SESSION;
 		goto error;
 	}