X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Ftrace-chunk.cpp;h=eed3d558b0181d269501fb485e7ec63298a8f8d5;hp=f38a93b90930b3abd357574a34f009d1807f17b1;hb=HEAD;hpb=e665dfbce25215d5ec77ff03a279c7163b337db1

diff --git a/src/common/trace-chunk.cpp b/src/common/trace-chunk.cpp
index f38a93b90..5da16a613 100644
--- a/src/common/trace-chunk.cpp
+++ b/src/common/trace-chunk.cpp
@@ -21,6 +21,7 @@
 #include <common/time.hpp>
 #include <common/trace-chunk-registry.hpp>
 #include <common/trace-chunk.hpp>
+#include <common/urcu.hpp>
 #include <common/utils.hpp>
 
 #include <lttng/constant.h>
@@ -188,7 +189,7 @@ static struct fs_handle *fs_handle_untracked_create(struct lttng_directory_handl
 						    const char *path,
 						    int fd)
 {
-	struct fs_handle_untracked *handle = NULL;
+	struct fs_handle_untracked *handle = nullptr;
 	bool reference_acquired;
 	char *path_copy = strdup(path);
 
@@ -217,10 +218,10 @@ static struct fs_handle *fs_handle_untracked_create(struct lttng_directory_handl
 	handle->location.directory_handle = directory_handle;
 	/* Ownership is transferred. */
 	handle->location.path = path_copy;
-	path_copy = NULL;
+	path_copy = nullptr;
 end:
 	free(path_copy);
-	return handle ? &handle->parent : NULL;
+	return handle ? &handle->parent : nullptr;
 }
 
 static int fs_handle_untracked_get_fd(struct fs_handle *_handle)
@@ -305,7 +306,7 @@ static char *
 generate_chunk_name(uint64_t chunk_id, time_t creation_timestamp, const time_t *close_timestamp)
 {
 	int ret = 0;
-	char *new_name = NULL;
+	char *new_name = nullptr;
 	char start_datetime[ISO8601_STR_LEN] = {};
 	/* Add 1 for a '-' prefix. */
 	char end_datetime_suffix[ISO8601_STR_LEN + 1] = {};
@@ -343,13 +344,13 @@ generate_chunk_name(uint64_t chunk_id, time_t creation_timestamp, const time_t *
 	return new_name;
 error:
 	free(new_name);
-	return NULL;
+	return nullptr;
 }
 
 static void lttng_trace_chunk_init(struct lttng_trace_chunk *chunk)
 {
 	urcu_ref_init(&chunk->ref);
-	pthread_mutex_init(&chunk->lock, NULL);
+	pthread_mutex_init(&chunk->lock, nullptr);
 	lttng_dynamic_pointer_array_init(&chunk->top_level_directories, free);
 	lttng_dynamic_pointer_array_init(&chunk->files, free);
 }
@@ -358,24 +359,24 @@ static void lttng_trace_chunk_fini(struct lttng_trace_chunk *chunk)
 {
 	if (chunk->session_output_directory) {
 		lttng_directory_handle_put(chunk->session_output_directory);
-		chunk->session_output_directory = NULL;
+		chunk->session_output_directory = nullptr;
 	}
 	if (chunk->chunk_directory) {
 		lttng_directory_handle_put(chunk->chunk_directory);
-		chunk->chunk_directory = NULL;
+		chunk->chunk_directory = nullptr;
 	}
 	free(chunk->name);
-	chunk->name = NULL;
+	chunk->name = nullptr;
 	free(chunk->path);
-	chunk->path = NULL;
+	chunk->path = nullptr;
 	lttng_dynamic_pointer_array_reset(&chunk->top_level_directories);
 	lttng_dynamic_pointer_array_reset(&chunk->files);
 	pthread_mutex_destroy(&chunk->lock);
 }
 
-static struct lttng_trace_chunk *lttng_trace_chunk_allocate(void)
+static struct lttng_trace_chunk *lttng_trace_chunk_allocate()
 {
-	struct lttng_trace_chunk *chunk = NULL;
+	struct lttng_trace_chunk *chunk = nullptr;
 
 	chunk = zmalloc<lttng_trace_chunk>();
 	if (!chunk) {
@@ -387,7 +388,7 @@ end:
 	return chunk;
 }
 
-struct lttng_trace_chunk *lttng_trace_chunk_create_anonymous(void)
+struct lttng_trace_chunk *lttng_trace_chunk_create_anonymous()
 {
 	DBG("Creating anonymous trace chunk");
 	return lttng_trace_chunk_allocate();
@@ -426,7 +427,7 @@ lttng_trace_chunk_create(uint64_t chunk_id, time_t chunk_creation_time, const ch
 	LTTNG_OPTIONAL_SET(&chunk->id, chunk_id);
 	LTTNG_OPTIONAL_SET(&chunk->timestamp_creation, chunk_creation_time);
 	if (chunk_id != 0) {
-		chunk->name = generate_chunk_name(chunk_id, chunk_creation_time, NULL);
+		chunk->name = generate_chunk_name(chunk_id, chunk_creation_time, nullptr);
 		if (!chunk->name) {
 			ERR("Failed to allocate trace chunk name storage");
 			goto error;
@@ -451,7 +452,7 @@ end:
 	return chunk;
 error:
 	lttng_trace_chunk_put(chunk);
-	return NULL;
+	return nullptr;
 }
 
 void lttng_trace_chunk_set_fd_tracker(struct lttng_trace_chunk *chunk,
@@ -526,7 +527,7 @@ end:
 error_unlock:
 	pthread_mutex_unlock(&source_chunk->lock);
 	lttng_trace_chunk_put(new_chunk);
-	return NULL;
+	return nullptr;
 }
 
 enum lttng_trace_chunk_status lttng_trace_chunk_get_id(struct lttng_trace_chunk *chunk,
@@ -718,7 +719,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 
 {
 	enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
-	struct lttng_directory_handle *rename_directory = NULL;
+	struct lttng_directory_handle *rename_directory = nullptr;
 	char *new_path, *old_path;
 	int ret;
 
@@ -763,7 +764,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 			chunk->session_output_directory,
 			path,
 			LTTNG_OPTIONAL_GET(chunk->credentials).use_current_user ?
-				NULL :
+				nullptr :
 				&chunk->credentials.value.user);
 		if (ret) {
 			PERROR("Failed to move trace chunk directory \"%s\" to \"%s\"",
@@ -790,7 +791,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 		 * handle.
 		 */
 		chunk->chunk_directory = rename_directory;
-		rename_directory = NULL;
+		rename_directory = nullptr;
 	} else if (old_path && old_path[0] == '\0') {
 		size_t i,
 			count = lttng_dynamic_pointer_array_get_count(
@@ -801,7 +802,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 			path,
 			DIR_CREATION_MODE,
 			LTTNG_OPTIONAL_GET(chunk->credentials).use_current_user ?
-				NULL :
+				nullptr :
 				&chunk->credentials.value.user);
 		if (ret) {
 			PERROR("Failed to create trace chunk rename directory \"%s\"", path);
@@ -829,7 +830,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 				rename_directory,
 				top_level_name,
 				LTTNG_OPTIONAL_GET(chunk->credentials).use_current_user ?
-					NULL :
+					nullptr :
 					&chunk->credentials.value.user);
 			if (ret) {
 				PERROR("Failed to move \"%s\" to trace chunk rename directory",
@@ -845,7 +846,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 		 * handle.
 		 */
 		chunk->chunk_directory = rename_directory;
-		rename_directory = NULL;
+		rename_directory = nullptr;
 	} else if (old_path) {
 		size_t i,
 			count = lttng_dynamic_pointer_array_get_count(
@@ -868,7 +869,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 				rename_directory,
 				top_level_name,
 				LTTNG_OPTIONAL_GET(chunk->credentials).use_current_user ?
-					NULL :
+					nullptr :
 					&chunk->credentials.value.user);
 			if (ret) {
 				PERROR("Failed to move \"%s\" to trace chunk rename directory",
@@ -884,7 +885,7 @@ lttng_trace_chunk_rename_path_no_lock(struct lttng_trace_chunk *chunk, const cha
 		 * handle.
 		 */
 		chunk->chunk_directory = rename_directory;
-		rename_directory = NULL;
+		rename_directory = nullptr;
 
 		/* Remove old directory. */
 		status = (lttng_trace_chunk_status) lttng_directory_handle_remove_subdirectory(
@@ -994,7 +995,7 @@ lttng_trace_chunk_set_as_owner(struct lttng_trace_chunk *chunk,
 {
 	int ret;
 	enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
-	struct lttng_directory_handle *chunk_directory_handle = NULL;
+	struct lttng_directory_handle *chunk_directory_handle = nullptr;
 	bool reference_acquired;
 
 	pthread_mutex_lock(&chunk->lock);
@@ -1018,7 +1019,7 @@ lttng_trace_chunk_set_as_owner(struct lttng_trace_chunk *chunk,
 			DIR_CREATION_MODE,
 			!chunk->credentials.value.use_current_user ?
 				&chunk->credentials.value.user :
-				NULL);
+				nullptr);
 		if (ret) {
 			PERROR("Failed to create chunk output directory \"%s\"", chunk->path);
 			status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
@@ -1045,7 +1046,7 @@ lttng_trace_chunk_set_as_owner(struct lttng_trace_chunk *chunk,
 		chunk_directory_handle = session_output_directory;
 	}
 	chunk->chunk_directory = chunk_directory_handle;
-	chunk_directory_handle = NULL;
+	chunk_directory_handle = nullptr;
 	reference_acquired = lttng_directory_handle_get(session_output_directory);
 	LTTNG_ASSERT(reference_acquired);
 	chunk->session_output_directory = session_output_directory;
@@ -1090,7 +1091,7 @@ lttng_trace_chunk_get_session_output_directory_handle(struct lttng_trace_chunk *
 	pthread_mutex_lock(&chunk->lock);
 	if (!chunk->session_output_directory) {
 		status = LTTNG_TRACE_CHUNK_STATUS_NONE;
-		*handle = NULL;
+		*handle = nullptr;
 		goto end;
 	} else {
 		const bool reference_acquired =
@@ -1207,7 +1208,8 @@ enum lttng_trace_chunk_status lttng_trace_chunk_create_subdirectory(struct lttng
 		chunk->chunk_directory,
 		path,
 		DIR_CREATION_MODE,
-		chunk->credentials.value.use_current_user ? NULL : &chunk->credentials.value.user);
+		chunk->credentials.value.use_current_user ? nullptr :
+							    &chunk->credentials.value.user);
 	if (ret) {
 		PERROR("Failed to create trace chunk subdirectory \"%s\"", path);
 		status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
@@ -1252,7 +1254,7 @@ static enum lttng_trace_chunk_status lttng_trace_chunk_add_file(struct lttng_tra
 	int ret;
 	enum lttng_trace_chunk_status status = LTTNG_TRACE_CHUNK_STATUS_OK;
 
-	if (lttng_trace_chunk_find_file(chunk, path, NULL)) {
+	if (lttng_trace_chunk_find_file(chunk, path, nullptr)) {
 		return LTTNG_TRACE_CHUNK_STATUS_OK;
 	}
 	DBG("Adding new file \"%s\" to trace chunk \"%s\"", path, chunk->name ?: "(unnamed)");
@@ -1330,7 +1332,7 @@ _lttng_trace_chunk_open_fs_handle_locked(struct lttng_trace_chunk *chunk,
 			file_path,
 			flags,
 			mode,
-			chunk->credentials.value.use_current_user ? NULL :
+			chunk->credentials.value.use_current_user ? nullptr :
 								    &chunk->credentials.value.user);
 		if (ret >= 0) {
 			*out_handle =
@@ -1429,10 +1431,11 @@ int lttng_trace_chunk_unlink_file(struct lttng_trace_chunk *chunk, const char *f
 		status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
 		goto end;
 	}
-	ret = lttng_directory_handle_unlink_file_as_user(
-		chunk->chunk_directory,
-		file_path,
-		chunk->credentials.value.use_current_user ? NULL : &chunk->credentials.value.user);
+	ret = lttng_directory_handle_unlink_file_as_user(chunk->chunk_directory,
+							 file_path,
+							 chunk->credentials.value.use_current_user ?
+								 nullptr :
+								 &chunk->credentials.value.user);
 	if (ret < 0) {
 		status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
 		goto end;
@@ -1470,7 +1473,8 @@ static int lttng_trace_chunk_remove_subdirectory_recursive(struct lttng_trace_ch
 	ret = lttng_directory_handle_remove_subdirectory_recursive_as_user(
 		chunk->chunk_directory,
 		path,
-		chunk->credentials.value.use_current_user ? NULL : &chunk->credentials.value.user,
+		chunk->credentials.value.use_current_user ? nullptr :
+							    &chunk->credentials.value.user,
 		LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG);
 	if (ret < 0) {
 		status = LTTNG_TRACE_CHUNK_STATUS_ERROR;
@@ -1484,11 +1488,11 @@ end:
 static int lttng_trace_chunk_move_to_completed_post_release(struct lttng_trace_chunk *trace_chunk)
 {
 	int ret = 0;
-	char *archived_chunk_name = NULL;
+	char *archived_chunk_name = nullptr;
 	const uint64_t chunk_id = LTTNG_OPTIONAL_GET(trace_chunk->id);
 	const time_t creation_timestamp = LTTNG_OPTIONAL_GET(trace_chunk->timestamp_creation);
 	const time_t close_timestamp = LTTNG_OPTIONAL_GET(trace_chunk->timestamp_close);
-	struct lttng_directory_handle *archived_chunks_directory = NULL;
+	struct lttng_directory_handle *archived_chunks_directory = nullptr;
 	enum lttng_trace_chunk_status status;
 
 	if (!trace_chunk->mode.is_set || trace_chunk->mode.value != TRACE_CHUNK_MODE_OWNER ||
@@ -1517,7 +1521,7 @@ static int lttng_trace_chunk_move_to_completed_post_release(struct lttng_trace_c
 		DIR_CREATION_MODE,
 		!trace_chunk->credentials.value.use_current_user ?
 			&trace_chunk->credentials.value.user :
-			NULL);
+			nullptr);
 	if (ret) {
 		PERROR("Failed to create \"" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY
 		       "\" directory for archived trace chunks");
@@ -1542,7 +1546,7 @@ static int lttng_trace_chunk_move_to_completed_post_release(struct lttng_trace_c
 	 * the creation of the next chunk. This happens if a rotation is
 	 * performed while tracing is stopped.
 	 */
-	if (!trace_chunk->path || strcmp(trace_chunk->path, DEFAULT_CHUNK_TMP_OLD_DIRECTORY)) {
+	if (!trace_chunk->path || strcmp(trace_chunk->path, DEFAULT_CHUNK_TMP_OLD_DIRECTORY) != 0) {
 		status = lttng_trace_chunk_rename_path_no_lock(trace_chunk,
 							       DEFAULT_CHUNK_TMP_OLD_DIRECTORY);
 		if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
@@ -1558,7 +1562,7 @@ static int lttng_trace_chunk_move_to_completed_post_release(struct lttng_trace_c
 		archived_chunks_directory,
 		archived_chunk_name,
 		LTTNG_OPTIONAL_GET(trace_chunk->credentials).use_current_user ?
-			NULL :
+			nullptr :
 			&trace_chunk->credentials.value.user);
 	if (ret) {
 		PERROR("Failed to rename folder \"%s\" to \"%s\"",
@@ -1639,7 +1643,7 @@ static int lttng_trace_chunk_delete_post_release_owner(struct lttng_trace_chunk
 	}
 	if (!ret) {
 		lttng_directory_handle_put(trace_chunk->chunk_directory);
-		trace_chunk->chunk_directory = NULL;
+		trace_chunk->chunk_directory = nullptr;
 
 		if (trace_chunk->path && trace_chunk->path[0] != '\0') {
 			status = (lttng_trace_chunk_status)
@@ -1653,7 +1657,7 @@ static int lttng_trace_chunk_delete_post_release_owner(struct lttng_trace_chunk
 		}
 	}
 	free(trace_chunk->path);
-	trace_chunk->path = NULL;
+	trace_chunk->path = nullptr;
 end:
 	return ret;
 }
@@ -1824,9 +1828,8 @@ static void lttng_trace_chunk_release(struct urcu_ref *ref)
 		element = lttng::utils::container_of(chunk,
 						     &lttng_trace_chunk_registry_element::chunk);
 		if (element->registry) {
-			rcu_read_lock();
+			lttng::urcu::read_lock_guard read_lock;
 			cds_lfht_del(element->registry->ht, &element->trace_chunk_registry_ht_node);
-			rcu_read_unlock();
 			call_rcu(&element->rcu_node, free_lttng_trace_chunk_registry_element);
 		} else {
 			/* Never published, can be free'd immediately. */
@@ -1848,7 +1851,7 @@ void lttng_trace_chunk_put(struct lttng_trace_chunk *chunk)
 	urcu_ref_put(&chunk->ref, lttng_trace_chunk_release);
 }
 
-struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create(void)
+struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create()
 {
 	struct lttng_trace_chunk_registry *registry;
 
@@ -1858,7 +1861,7 @@ struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create(void)
 	}
 
 	registry->ht = cds_lfht_new(
-		DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+		DEFAULT_HT_SIZE, 1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, nullptr);
 	if (!registry->ht) {
 		goto error;
 	}
@@ -1866,7 +1869,7 @@ end:
 	return registry;
 error:
 	lttng_trace_chunk_registry_destroy(registry);
-	return NULL;
+	return nullptr;
 }
 
 void lttng_trace_chunk_registry_destroy(struct lttng_trace_chunk_registry *registry)
@@ -1875,7 +1878,7 @@ void lttng_trace_chunk_registry_destroy(struct lttng_trace_chunk_registry *regis
 		return;
 	}
 	if (registry->ht) {
-		int ret = cds_lfht_destroy(registry->ht, NULL);
+		int ret = cds_lfht_destroy(registry->ht, nullptr);
 		LTTNG_ASSERT(!ret);
 	}
 	free(registry);
@@ -1899,19 +1902,19 @@ lttng_trace_chunk_registry_element_create_from_chunk(struct lttng_trace_chunk *c
 	if (chunk->session_output_directory) {
 		/* Transferred ownership. */
 		element->chunk.session_output_directory = chunk->session_output_directory;
-		chunk->session_output_directory = NULL;
+		chunk->session_output_directory = nullptr;
 	}
 	if (chunk->chunk_directory) {
 		/* Transferred ownership. */
 		element->chunk.chunk_directory = chunk->chunk_directory;
-		chunk->chunk_directory = NULL;
+		chunk->chunk_directory = nullptr;
 	}
 	/*
 	 * The original chunk becomes invalid; the name and path attributes are
 	 * transferred to the new chunk instance.
 	 */
-	chunk->name = NULL;
-	chunk->path = NULL;
+	chunk->name = nullptr;
+	chunk->path = nullptr;
 	element->chunk.fd_tracker = chunk->fd_tracker;
 	element->chunk.in_registry_element = true;
 end:
@@ -1940,6 +1943,8 @@ lttng_trace_chunk_registry_publish_chunk(struct lttng_trace_chunk_registry *regi
 	pthread_mutex_lock(&chunk->lock);
 	element = lttng_trace_chunk_registry_element_create_from_chunk(chunk, session_id);
 	pthread_mutex_unlock(&chunk->lock);
+
+	lttng::urcu::read_lock_guard read_lock;
 	if (!element) {
 		goto end;
 	}
@@ -1947,11 +1952,10 @@ lttng_trace_chunk_registry_publish_chunk(struct lttng_trace_chunk_registry *regi
 	 * chunk is now invalid, the only valid operation is a 'put' from the
 	 * caller.
 	 */
-	chunk = NULL;
+	chunk = nullptr;
 	element_hash = lttng_trace_chunk_registry_element_hash(element);
 
-	rcu_read_lock();
-	while (1) {
+	while (true) {
 		struct cds_lfht_node *published_node;
 		struct lttng_trace_chunk *published_chunk;
 		struct lttng_trace_chunk_registry_element *published_element;
@@ -2002,9 +2006,8 @@ lttng_trace_chunk_registry_publish_chunk(struct lttng_trace_chunk_registry *regi
 		 * chunk.
 		 */
 	}
-	rcu_read_unlock();
 end:
-	return element ? &element->chunk : NULL;
+	return element ? &element->chunk : nullptr;
 }
 
 /*
@@ -2028,10 +2031,10 @@ static struct lttng_trace_chunk *_lttng_trace_chunk_registry_find_chunk(
 	const unsigned long element_hash = lttng_trace_chunk_registry_element_hash(&target_element);
 	struct cds_lfht_node *published_node;
 	struct lttng_trace_chunk_registry_element *published_element;
-	struct lttng_trace_chunk *published_chunk = NULL;
+	struct lttng_trace_chunk *published_chunk = nullptr;
 	struct cds_lfht_iter iter;
 
-	rcu_read_lock();
+	lttng::urcu::read_lock_guard read_lock;
 	cds_lfht_lookup(registry->ht,
 			element_hash,
 			lttng_trace_chunk_registry_element_match,
@@ -2048,7 +2051,6 @@ static struct lttng_trace_chunk *_lttng_trace_chunk_registry_find_chunk(
 		published_chunk = &published_element->chunk;
 	}
 end:
-	rcu_read_unlock();
 	return published_chunk;
 }
 
@@ -2074,7 +2076,7 @@ int lttng_trace_chunk_registry_chunk_exists(const struct lttng_trace_chunk_regis
 	struct cds_lfht_node *published_node;
 	struct cds_lfht_iter iter;
 
-	rcu_read_lock();
+	lttng::urcu::read_lock_guard read_lock;
 	cds_lfht_lookup(registry->ht,
 			element_hash,
 			lttng_trace_chunk_registry_element_match,
@@ -2088,7 +2090,6 @@ int lttng_trace_chunk_registry_chunk_exists(const struct lttng_trace_chunk_regis
 
 	*chunk_exists = !cds_lfht_is_node_deleted(published_node);
 end:
-	rcu_read_unlock();
 	return ret;
 }
 
@@ -2096,7 +2097,7 @@ struct lttng_trace_chunk *
 lttng_trace_chunk_registry_find_anonymous_chunk(const struct lttng_trace_chunk_registry *registry,
 						uint64_t session_id)
 {
-	return _lttng_trace_chunk_registry_find_chunk(registry, session_id, NULL);
+	return _lttng_trace_chunk_registry_find_chunk(registry, session_id, nullptr);
 }
 
 unsigned int
@@ -2107,37 +2108,42 @@ lttng_trace_chunk_registry_put_each_chunk(const struct lttng_trace_chunk_registr
 	unsigned int trace_chunks_left = 0;
 
 	DBG("Releasing trace chunk registry to all trace chunks");
-	rcu_read_lock();
-	cds_lfht_for_each_entry (registry->ht, &iter, chunk_element, trace_chunk_registry_ht_node) {
-		const char *chunk_id_str = "none";
-		char chunk_id_buf[MAX_INT_DEC_LEN(uint64_t)];
-
-		pthread_mutex_lock(&chunk_element->chunk.lock);
-		if (chunk_element->chunk.id.is_set) {
-			int fmt_ret;
-
-			fmt_ret = snprintf(chunk_id_buf,
-					   sizeof(chunk_id_buf),
-					   "%" PRIu64,
-					   chunk_element->chunk.id.value);
-			if (fmt_ret < 0 || fmt_ret >= sizeof(chunk_id_buf)) {
-				chunk_id_str = "formatting error";
-			} else {
-				chunk_id_str = chunk_id_buf;
+
+	{
+		lttng::urcu::read_lock_guard read_lock;
+
+		cds_lfht_for_each_entry (
+			registry->ht, &iter, chunk_element, trace_chunk_registry_ht_node) {
+			const char *chunk_id_str = "none";
+			char chunk_id_buf[MAX_INT_DEC_LEN(uint64_t)];
+
+			pthread_mutex_lock(&chunk_element->chunk.lock);
+			if (chunk_element->chunk.id.is_set) {
+				int fmt_ret;
+
+				fmt_ret = snprintf(chunk_id_buf,
+						   sizeof(chunk_id_buf),
+						   "%" PRIu64,
+						   chunk_element->chunk.id.value);
+				if (fmt_ret < 0 || fmt_ret >= sizeof(chunk_id_buf)) {
+					chunk_id_str = "formatting error";
+				} else {
+					chunk_id_str = chunk_id_buf;
+				}
 			}
+
+			DBG("Releasing reference to trace chunk: session_id = %" PRIu64
+			    "chunk_id = %s, name = \"%s\", status = %s",
+			    chunk_element->session_id,
+			    chunk_id_str,
+			    chunk_element->chunk.name ?: "none",
+			    chunk_element->chunk.close_command.is_set ? "open" : "closed");
+			pthread_mutex_unlock(&chunk_element->chunk.lock);
+			lttng_trace_chunk_put(&chunk_element->chunk);
+			trace_chunks_left++;
 		}
+	}
 
-		DBG("Releasing reference to trace chunk: session_id = %" PRIu64
-		    "chunk_id = %s, name = \"%s\", status = %s",
-		    chunk_element->session_id,
-		    chunk_id_str,
-		    chunk_element->chunk.name ?: "none",
-		    chunk_element->chunk.close_command.is_set ? "open" : "closed");
-		pthread_mutex_unlock(&chunk_element->chunk.lock);
-		lttng_trace_chunk_put(&chunk_element->chunk);
-		trace_chunks_left++;
-	}
-	rcu_read_unlock();
 	DBG("Released reference to %u trace chunks in %s()", trace_chunks_left, __FUNCTION__);
 
 	return trace_chunks_left;