X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fchannel.c;h=049c784b379102b36e2b362cc5ab69e05b47f78b;hp=5aa0cd82b60884782e7a60644c0715e9b8e10176;hb=ac1889bfdcb77622bbc818352d65634209d9829f;hpb=491d15395b58df09f8a3e7ba7404eb1f46392b79

diff --git a/src/bin/lttng-sessiond/channel.c b/src/bin/lttng-sessiond/channel.c
index 5aa0cd82b..049c784b3 100644
--- a/src/bin/lttng-sessiond/channel.c
+++ b/src/bin/lttng-sessiond/channel.c
@@ -1,19 +1,9 @@
 /*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
 #define _LGPL_SOURCE
@@ -28,7 +18,8 @@
 #include "channel.h"
 #include "lttng-sessiond.h"
 #include "kernel.h"
-#include "ust-ctl.h"
+#include "lttng-ust-ctl.h"
+#include "lttng-ust-error.h"
 #include "utils.h"
 #include "ust-app.h"
 #include "agent.h"
@@ -259,11 +250,6 @@ int channel_kernel_create(struct ltt_kernel_session *ksession,
 		attr->attr.overwrite = !!ksession->snapshot_mode;
 	}
 
-	/* Enforce mmap output for snapshot sessions. */
-	if (ksession->snapshot_mode) {
-		attr->attr.output = LTTNG_EVENT_MMAP;
-	}
-
 	/* Validate common channel properties. */
 	if (channel_validate(attr) < 0) {
 		ret = LTTNG_ERR_INVALID;
@@ -311,6 +297,18 @@ int channel_ust_enable(struct ltt_ust_session *usess,
 		DBG3("Channel %s already enabled. Skipping", uchan->name);
 		ret = LTTNG_ERR_UST_CHAN_EXIST;
 		goto end;
+	} else {
+		uchan->enabled = 1;
+		DBG2("Channel %s enabled successfully", uchan->name);
+	}
+
+	if (!usess->active) {
+		/*
+		 * The channel will be activated against the apps
+		 * when the session is started as part of the
+		 * application channel "synchronize" operation.
+		 */
+		goto end;
 	}
 
 	DBG2("Channel %s being enabled in UST domain", uchan->name);
@@ -325,8 +323,6 @@ int channel_ust_enable(struct ltt_ust_session *usess,
 	 */
 	(void) ust_app_enable_channel_glb(usess, uchan);
 
-	uchan->enabled = 1;
-	DBG2("Channel %s enabled successfully", uchan->name);
 
 end:
 	return ret;
@@ -342,6 +338,7 @@ int channel_ust_create(struct ltt_ust_session *usess,
 	struct ltt_ust_channel *uchan = NULL;
 	struct lttng_channel *defattr = NULL;
 	enum lttng_domain_type domain = LTTNG_DOMAIN_UST;
+	bool chan_published = false;
 
 	assert(usess);
 
@@ -464,18 +461,12 @@ int channel_ust_create(struct ltt_ust_session *usess,
 		goto error_free_chan;
 	}
 
-	/* Enable channel for global domain */
-	ret = ust_app_create_channel_glb(usess, uchan);
-	if (ret < 0 && ret != -LTTNG_UST_ERR_EXIST) {
-		ret = LTTNG_ERR_UST_CHAN_FAIL;
-		goto error_free_chan;
-	}
-
 	/* Adding the channel to the channel hash table. */
 	rcu_read_lock();
 	if (strncmp(uchan->name, DEFAULT_METADATA_NAME,
 				sizeof(uchan->name))) {
 		lttng_ht_add_unique_str(usess->domain_global.channels, &uchan->node);
+		chan_published = true;
 	} else {
 		/*
 		 * Copy channel attribute to session if this is metadata so if NO
@@ -495,7 +486,7 @@ int channel_ust_create(struct ltt_ust_session *usess,
 			agt = agent_create(domain);
 			if (!agt) {
 				ret = LTTNG_ERR_NOMEM;
-				goto error_free_chan;
+				goto error_remove_chan;
 			}
 			agent_add(agt, usess->agents);
 		}
@@ -504,11 +495,11 @@ int channel_ust_create(struct ltt_ust_session *usess,
 	channel_attr_destroy(defattr);
 	return LTTNG_OK;
 
+error_remove_chan:
+	if (chan_published) {
+		trace_ust_delete_channel(usess->domain_global.channels, uchan);
+	}
 error_free_chan:
-	/*
-	 * No need to remove the channel from the hash table because at this point
-	 * it was not added hence the direct call and no call_rcu().
-	 */
 	trace_ust_destroy_channel(uchan);
 error:
 	channel_attr_destroy(defattr);
@@ -531,6 +522,9 @@ int channel_ust_disable(struct ltt_ust_session *usess,
 		DBG2("Channel UST %s already disabled", uchan->name);
 		goto end;
 	}
+	if (!usess->active) {
+		goto end;
+	}
 
 	DBG2("Channel %s being disabled in UST global domain", uchan->name);
 	/* Disable channel for global domain */