*
*/
+#include "ctf2-trace-class-visitor.hpp"
+#include "field.hpp"
+#include "lttng-sessiond.hpp"
+#include "notification-thread-commands.hpp"
+#include "session.hpp"
+#include "trace-class.hpp"
+#include "tsdl-trace-class-visitor.hpp"
+#include "ust-app.hpp"
+#include "ust-field-convert.hpp"
#include "ust-registry.hpp"
#include <common/compat/directory-handle.hpp>
#include <common/error.hpp>
#include <common/exception.hpp>
+#include <common/format.hpp>
+#include <common/hashtable/utils.hpp>
#include <common/macros.hpp>
+#include <common/make-unique.hpp>
#include <common/pthread-lock.hpp>
#include <common/runas.hpp>
+#include <common/time.hpp>
+#include <common/urcu.hpp>
#include <fcntl.h>
+#include <functional>
+#include <initializer_list>
+#include <mutex>
#include <sstream>
#include <string>
-ust_registry_session::ust_registry_session(uint32_t bits_per_long,
- uint32_t uint8_t_alignment,
- uint32_t uint16_t_alignment,
- uint32_t uint32_t_alignment,
- uint32_t uint64_t_alignment,
- uint32_t long_alignment,
- int byte_order,
- uint32_t major,
- uint32_t minor,
- const char *root_shm_path,
- const char *shm_path,
- uid_t euid,
- gid_t egid,
- uint64_t tracing_id) :
- _bits_per_long{bits_per_long},
- _uint8_t_alignment{uint8_t_alignment},
- _uint16_t_alignment{uint16_t_alignment},
- _uint32_t_alignment{uint32_t_alignment},
- _uint64_t_alignment{uint64_t_alignment},
- _long_alignment{long_alignment},
- _byte_order{byte_order},
- _uid{euid},
- _gid{egid},
- _app_tracer_version_major{major},
- _app_tracer_version_minor{minor},
- _tracing_id{tracing_id}
-{
- pthread_mutex_init(&_lock, NULL);
- strncpy(_root_shm_path, root_shm_path, sizeof(_root_shm_path));
- _root_shm_path[sizeof(_root_shm_path) - 1] = '\0';
- if (shm_path[0]) {
- strncpy(_shm_path, shm_path, sizeof(_shm_path));
- _shm_path[sizeof(_shm_path) - 1] = '\0';
- strncpy(_metadata_path, shm_path, sizeof(_metadata_path));
- _metadata_path[sizeof(_metadata_path) - 1] = '\0';
- strncat(_metadata_path, "/metadata",
- sizeof(_metadata_path) - strlen(_metadata_path) - 1);
- }
-
- if (_shm_path[0]) {
- if (run_as_mkdir_recursive(_shm_path, S_IRWXU | S_IRWXG, euid, egid)) {
+namespace ls = lttng::sessiond;
+namespace lst = lttng::sessiond::trace;
+namespace lsu = lttng::sessiond::ust;
+
+namespace {
+lttng_uuid generate_uuid_or_throw()
+{
+ lttng_uuid new_uuid;
+
+ if (lttng_uuid_generate(new_uuid)) {
+ LTTNG_THROW_POSIX("Failed to generate UST uuid", errno);
+ }
+
+ return new_uuid;
+}
+
+int get_count_order(unsigned int count)
+{
+ int order;
+
+ order = lttng_fls(count) - 1;
+ if (count & (count - 1)) {
+ order++;
+ }
+
+ LTTNG_ASSERT(order >= 0);
+ return order;
+}
+
+void clear_metadata_file(int fd)
+{
+ const auto lseek_ret = lseek(fd, 0, SEEK_SET);
+ if (lseek_ret < 0) {
+ LTTNG_THROW_POSIX(
+ "Failed to seek to the beginning of the metadata file while clearing it",
+ errno);
+ }
+
+ const auto ret = ftruncate(fd, 0);
+ if (ret < 0) {
+ LTTNG_THROW_POSIX("Failed to truncate the metadata file while clearing it", errno);
+ }
+}
+
+/*
+ * Validate that the id has reached the maximum allowed or not.
+ */
+bool is_max_channel_id(uint32_t id)
+{
+ return id == UINT32_MAX;
+}
+
+void destroy_channel_rcu(struct rcu_head *head)
+{
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ lsu::registry_channel *chan =
+ lttng::utils::container_of(head, &lsu::registry_channel::_rcu_head);
+ DIAGNOSTIC_POP
+
+ delete chan;
+}
+
+/*
+ * Destroy every element of the registry and free the memory. This does NOT
+ * free the registry pointer since it might not have been allocated before so
+ * it's the caller responsability.
+ *
+ * Called from ~registry_session(), must not throw.
+ */
+void destroy_channel(lsu::registry_channel *chan, bool notify) noexcept
+{
+ struct lttng_ht_iter iter;
+ lttng::sessiond::ust::registry_event *event;
+ enum lttng_error_code cmd_ret;
+
+ LTTNG_ASSERT(chan);
+
+ if (notify) {
+ cmd_ret = notification_thread_command_remove_channel(
+ the_notification_thread_handle, chan->_consumer_key, LTTNG_DOMAIN_UST);
+ if (cmd_ret != LTTNG_OK) {
+ ERR("Failed to remove channel from notification thread");
+ }
+ }
+
+ if (chan->_events) {
+ lttng::urcu::read_lock_guard read_lock_guard;
+
+ /* Destroy all event associated with this registry. */
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ cds_lfht_for_each_entry (chan->_events->ht, &iter.iter, event, _node) {
+ /* Delete the node from the ht and free it. */
+ ust_registry_channel_destroy_event(chan, event);
+ }
+ DIAGNOSTIC_POP
+ }
+
+ call_rcu(&chan->_rcu_head, destroy_channel_rcu);
+}
+
+void destroy_enum(lsu::registry_enum *reg_enum)
+{
+ if (!reg_enum) {
+ return;
+ }
+
+ delete reg_enum;
+}
+
+void destroy_enum_rcu(struct rcu_head *head)
+{
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ lsu::registry_enum *reg_enum =
+ lttng::utils::container_of(head, &lsu::registry_enum::rcu_head);
+ DIAGNOSTIC_POP
+
+ destroy_enum(reg_enum);
+}
+
+/*
+ * Hash table match function for enumerations in the session. Match is
+ * performed on enumeration name, and confirmed by comparing the enum
+ * entries.
+ */
+int ht_match_enum(struct cds_lfht_node *node, const void *_key)
+{
+ lsu::registry_enum *_enum;
+ const lsu::registry_enum *key;
+
+ LTTNG_ASSERT(node);
+ LTTNG_ASSERT(_key);
+
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ _enum = caa_container_of(node, lsu::registry_enum, node.node);
+ DIAGNOSTIC_POP
+
+ LTTNG_ASSERT(_enum);
+ key = (lsu::registry_enum *) _key;
+
+ return *_enum == *key;
+}
+
+/*
+ * Hash table match function for enumerations in the session. Match is
+ * performed by enumeration ID.
+ */
+int ht_match_enum_id(struct cds_lfht_node *node, const void *_key)
+{
+ lsu::registry_enum *_enum;
+ const lsu::registry_enum *key = (lsu::registry_enum *) _key;
+
+ LTTNG_ASSERT(node);
+ LTTNG_ASSERT(_key);
+
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ _enum = caa_container_of(node, lsu::registry_enum, node.node);
+ DIAGNOSTIC_POP
+
+ LTTNG_ASSERT(_enum);
+
+ if (_enum->id != key->id) {
+ goto no_match;
+ }
+
+ /* Match. */
+ return 1;
+
+no_match:
+ return 0;
+}
+
+/*
+ * Hash table hash function for enumerations in the session. The
+ * enumeration name is used for hashing.
+ */
+unsigned long ht_hash_enum(void *_key, unsigned long seed)
+{
+ lsu::registry_enum *key = (lsu::registry_enum *) _key;
+
+ LTTNG_ASSERT(key);
+ return hash_key_str(key->name.c_str(), seed);
+}
+} /* namespace */
+
+void lsu::details::locked_registry_session_release(lsu::registry_session *session)
+{
+ pthread_mutex_unlock(&session->_lock);
+}
+
+lsu::registry_session::registry_session(const struct lst::abi& in_abi,
+ uint32_t major,
+ uint32_t minor,
+ const char *root_shm_path,
+ const char *shm_path,
+ uid_t euid,
+ gid_t egid,
+ uint64_t tracing_id) :
+ lst::trace_class(in_abi, generate_uuid_or_throw()),
+ _root_shm_path{ root_shm_path ? root_shm_path : "" },
+ _shm_path{ shm_path ? shm_path : "" },
+ _metadata_path{ _shm_path.size() > 0 ? lttng::format("{}/metadata", _shm_path) :
+ std::string("") },
+ _uid{ euid },
+ _gid{ egid },
+ _app_tracer_version{ .major = major, .minor = minor },
+ _tracing_id{ tracing_id },
+ _clock{ lttng::make_unique<lsu::clock_class>() },
+ _metadata_generating_visitor{ lttng::make_unique<ls::tsdl::trace_class_visitor>(
+ abi,
+ [this](const std::string& fragment) { _append_metadata_fragment(fragment); }) },
+ _packet_header{ _create_packet_header() }
+{
+ pthread_mutex_init(&_lock, nullptr);
+ if (_shm_path.size() > 0) {
+ if (run_as_mkdir_recursive(_shm_path.c_str(), S_IRWXU | S_IRWXG, euid, egid)) {
LTTNG_THROW_POSIX("run_as_mkdir_recursive", errno);
}
}
- if (_metadata_path[0]) {
+ if (_metadata_path.size() > 0) {
/* Create metadata file. */
- const int ret = run_as_open(_metadata_path, O_WRONLY | O_CREAT | O_EXCL,
- S_IRUSR | S_IWUSR, euid, egid);
-
+ const int ret = run_as_open(_metadata_path.c_str(),
+ O_WRONLY | O_CREAT | O_EXCL,
+ S_IRUSR | S_IWUSR,
+ euid,
+ egid);
if (ret < 0) {
- std::stringstream ss;
-
- ss << "Opening metadata file '" << _metadata_path << "'";
- LTTNG_THROW_POSIX(ss.str(), errno);
+ LTTNG_THROW_POSIX(
+ lttng::format(
+ "Failed to open metadata file during registry session creation: path = {}",
+ _metadata_path),
+ errno);
}
_metadata_fd = ret;
}
/* hash/match functions are specified at call site. */
- _enums->match_fct = NULL;
- _enums->hash_fct = NULL;
+ _enums->match_fct = nullptr;
+ _enums->hash_fct = nullptr;
_channels.reset(lttng_ht_new(0, LTTNG_HT_TYPE_U64));
if (!_channels) {
LTTNG_THROW_POSIX("Failed to create channels hash table", ENOMEM);
}
+}
- if (lttng_uuid_generate(_uuid)) {
- LTTNG_THROW_POSIX("Failed to generate UST uuid", errno);
- }
+lst::type::cuptr lsu::registry_session::_create_packet_header() const
+{
+ lst::structure_type::fields packet_header_fields;
+
+ /* uint32_t magic */
+ packet_header_fields.emplace_back(lttng::make_unique<lst::field>(
+ "magic",
+ lttng::make_unique<lst::integer_type>(
+ abi.uint32_t_alignment,
+ abi.byte_order,
+ 32,
+ lst::integer_type::signedness::UNSIGNED,
+ lst::integer_type::base::HEXADECIMAL,
+ std::initializer_list<lst::integer_type::role>(
+ { lst::integer_type::role::PACKET_MAGIC_NUMBER }))));
+
+ /* uuid */
+ packet_header_fields.emplace_back(lttng::make_unique<lst::field>(
+ "uuid",
+ lttng::make_unique<lst::static_length_blob_type>(
+ 0,
+ 16,
+ std::initializer_list<lst::static_length_blob_type::role>(
+ { lst::static_length_blob_type::role::METADATA_STREAM_UUID }))));
+
+ /* uint32_t stream_id */
+ packet_header_fields.emplace_back(lttng::make_unique<lst::field>(
+ "stream_id",
+ lttng::make_unique<lst::integer_type>(
+ abi.uint32_t_alignment,
+ abi.byte_order,
+ 32,
+ lst::integer_type::signedness::UNSIGNED,
+ lst::integer_type::base::DECIMAL,
+ std::initializer_list<lst::integer_type::role>(
+ { lst::integer_type::role::DATA_STREAM_CLASS_ID }))));
+
+ /* uint64_t stream_instance_id */
+ packet_header_fields.emplace_back(lttng::make_unique<lst::field>(
+ "stream_instance_id",
+ lttng::make_unique<lst::integer_type>(
+ abi.uint64_t_alignment,
+ abi.byte_order,
+ 64,
+ lst::integer_type::signedness::UNSIGNED,
+ lst::integer_type::base::DECIMAL,
+ std::initializer_list<lst::integer_type::role>(
+ { lst::integer_type::role::DATA_STREAM_ID }))));
+
+ return lttng::make_unique<lst::structure_type>(0, std::move(packet_header_fields));
+}
+
+const lst::type *lsu::registry_session::packet_header() const noexcept
+{
+ return _packet_header.get();
}
-ust_registry_session::~ust_registry_session()
+/*
+ * For a given enumeration in a registry, delete the entry and destroy
+ * the enumeration.
+ *
+ * Note that this is used by ~registry_session() and must not throw.
+ */
+void lsu::registry_session::_destroy_enum(lsu::registry_enum *reg_enum) noexcept
{
int ret;
+ lttng::urcu::read_lock_guard read_lock_guard;
+
+ LTTNG_ASSERT(reg_enum);
+ ASSERT_RCU_READ_LOCKED();
+
+ /* Delete the node first. */
struct lttng_ht_iter iter;
- struct ust_registry_channel *chan;
- struct ust_registry_enum *reg_enum;
+ iter.iter.node = ®_enum->node.node;
+ ret = lttng_ht_del(_enums.get(), &iter);
+ LTTNG_ASSERT(!ret);
+ call_rcu(®_enum->rcu_head, destroy_enum_rcu);
+}
+
+lsu::registry_session::~registry_session()
+{
+ int ret;
+ struct lttng_ht_iter iter;
+ lsu::registry_channel *chan;
+ lsu::registry_enum *reg_enum;
/* On error, EBUSY can be returned if lock. Code flow error. */
ret = pthread_mutex_destroy(&_lock);
LTTNG_ASSERT(!ret);
if (_channels) {
- rcu_read_lock();
+ lttng::urcu::read_lock_guard read_lock_guard;
+
/* Destroy all event associated with this registry. */
- cds_lfht_for_each_entry (_channels->ht, &iter.iter, chan, node.node) {
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ cds_lfht_for_each_entry (_channels->ht, &iter.iter, chan, _node.node) {
/* Delete the node from the ht and free it. */
ret = lttng_ht_del(_channels.get(), &iter);
LTTNG_ASSERT(!ret);
- ust_registry_channel_destroy(chan, true);
+ destroy_channel(chan, true);
}
-
- rcu_read_unlock();
+ DIAGNOSTIC_POP
}
free(_metadata);
PERROR("close");
}
- ret = run_as_unlink(_metadata_path, _uid, _gid);
+ ret = run_as_unlink(_metadata_path.c_str(), _uid, _gid);
if (ret) {
PERROR("unlink");
}
if (_root_shm_path[0]) {
/* Try to delete the directory hierarchy. */
- (void) run_as_rmdir_recursive(_root_shm_path, _uid, _gid,
- LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG);
+ (void) run_as_rmdir_recursive(_root_shm_path.c_str(),
+ _uid,
+ _gid,
+ LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG);
}
/* Destroy the enum hash table */
if (_enums) {
- rcu_read_lock();
+ lttng::urcu::read_lock_guard read_lock_guard;
+
/* Destroy all enum entries associated with this registry. */
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
cds_lfht_for_each_entry (_enums->ht, &iter.iter, reg_enum, node.node) {
- ust_registry_destroy_enum(this, reg_enum);
+ _destroy_enum(reg_enum);
+ }
+ DIAGNOSTIC_POP
+ }
+}
+
+lsu::registry_session::locked_ptr lsu::registry_session::lock() noexcept
+{
+ pthread_mutex_lock(&_lock);
+ return locked_ptr(this);
+}
+
+/*
+ * Initialize registry with default values.
+ */
+void lsu::registry_session::add_channel(uint64_t key)
+{
+ lttng::pthread::lock_guard session_lock_guard(_lock);
+
+ /*
+ * Assign a channel ID right now since the event notification comes
+ * *before* the channel notify so the ID needs to be set at this point so
+ * the metadata can be dumped for that event.
+ */
+ if (is_max_channel_id(_used_channel_id)) {
+ LTTNG_THROW_ERROR(lttng::format(
+ "Failed to allocate unique id for channel under session while adding channel"));
+ }
+
+ auto chan = new lsu::registry_channel(
+ _get_next_channel_id(),
+ abi,
+ _clock->name,
+ /* Registered channel listener. */
+ [this](const lsu::registry_channel& registered_channel) {
+ /*
+ * Channel registration completed, serialize it's layout's
+ * description.
+ */
+ registered_channel.accept(*_metadata_generating_visitor);
+ },
+ /* Added event listener. */
+ [this](const lsu::registry_channel& channel,
+ const lsu::registry_event& added_event) {
+ /*
+ * The channel and its event classes will be dumped at once when
+ * it is registered. This check prevents event classes from being
+ * declared before their stream class.
+ */
+ if (channel.is_registered()) {
+ added_event.accept(*_metadata_generating_visitor);
+ }
+ });
+
+ lttng::urcu::read_lock_guard rcu_read_lock_guard;
+ lttng_ht_node_init_u64(&chan->_node, key);
+ lttng_ht_add_unique_u64(_channels.get(), &chan->_node);
+}
+
+lttng::sessiond::ust::registry_channel& lsu::registry_session::channel(uint64_t channel_key) const
+{
+ lttng::urcu::read_lock_guard read_lock_guard;
+ struct lttng_ht_node_u64 *node;
+ struct lttng_ht_iter iter;
+
+ ASSERT_LOCKED(_lock);
+
+ lttng_ht_lookup(_channels.get(), &channel_key, &iter);
+ node = lttng_ht_iter_get_node_u64(&iter);
+ if (!node) {
+ LTTNG_THROW_INVALID_ARGUMENT_ERROR(lttng::format(
+ "Invalid channel key provided: channel key = {}", channel_key));
+ }
+
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ auto chan = lttng::utils::container_of(node, &lsu::registry_channel::_node);
+ DIAGNOSTIC_POP
+ return *chan;
+}
+
+void lsu::registry_session::remove_channel(uint64_t channel_key, bool notify)
+{
+ struct lttng_ht_iter iter;
+ int ret;
+ lttng::urcu::read_lock_guard read_lock_guard;
+
+ ASSERT_LOCKED(_lock);
+ auto& channel_to_remove = channel(channel_key);
+
+ iter.iter.node = &channel_to_remove._node.node;
+ ret = lttng_ht_del(_channels.get(), &iter);
+ LTTNG_ASSERT(!ret);
+ destroy_channel(&channel_to_remove, notify);
+}
+
+void lsu::registry_session::accept(
+ lttng::sessiond::trace::trace_class_environment_visitor& visitor) const
+{
+ ASSERT_LOCKED(_lock);
+
+ visitor.visit(lst::environment_field<const char *>("domain", "ust"));
+ visitor.visit(lst::environment_field<const char *>("tracer_name", "lttng-ust"));
+ visitor.visit(lst::environment_field<int64_t>("tracer_major", _app_tracer_version.major));
+ visitor.visit(lst::environment_field<int64_t>("tracer_minor", _app_tracer_version.minor));
+ visitor.visit(lst::environment_field<const char *>(
+ "tracer_buffering_scheme",
+ buffering_scheme() == LTTNG_BUFFER_PER_PID ? "pid" : "uid"));
+ visitor.visit(lst::environment_field<int64_t>("architecture_bit_width", abi.bits_per_long));
+
+ {
+ /* The caller already holds the session and session list locks. */
+ ASSERT_SESSION_LIST_LOCKED();
+ const auto session = lttng::sessiond::find_session_by_id(_tracing_id);
+
+ LTTNG_ASSERT(session);
+ ASSERT_LOCKED(session->lock);
+
+ visitor.visit(lst::environment_field<const char *>(
+ "trace_name",
+ session->has_auto_generated_name ? DEFAULT_SESSION_NAME : session->name));
+ visitor.visit(lst::environment_field<std::string>(
+ "trace_creation_datetime",
+ lttng::utils::time_to_iso8601_str(session->creation_time)));
+ visitor.visit(lst::environment_field<const char *>("hostname", session->hostname));
+ }
+}
+
+void lsu::registry_session::_accept_on_clock_classes(lst::trace_class_visitor& visitor) const
+{
+ ASSERT_LOCKED(_lock);
+ _clock->accept(visitor);
+}
+
+void lsu::registry_session::_accept_on_stream_classes(lst::trace_class_visitor& visitor) const
+{
+ ASSERT_LOCKED(_lock);
+
+ std::vector<const lttng::sessiond::ust::registry_channel *> sorted_stream_classes;
+
+ {
+ lttng::urcu::read_lock_guard rcu_lock_guard;
+ const lsu::registry_channel *channel;
+ lttng_ht_iter channel_it;
+
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ cds_lfht_for_each_entry (_channels->ht, &channel_it.iter, channel, _node.node) {
+ sorted_stream_classes.emplace_back(channel);
}
+ DIAGNOSTIC_POP
+ }
- rcu_read_unlock();
+ std::sort(sorted_stream_classes.begin(),
+ sorted_stream_classes.end(),
+ [](const lttng::sessiond::ust::registry_channel *a,
+ const lttng::sessiond::ust::registry_channel *b) { return a->id < b->id; });
+
+ for (const auto stream_class : sorted_stream_classes) {
+ stream_class->accept(visitor);
}
}
-void ust_registry_session::statedump()
+/*
+ * Return next available channel id and increment the used counter. The
+ * is_max_channel_id function MUST be called before in order to validate
+ * if the maximum number of IDs have been reached. If not, it is safe to call
+ * this function.
+ *
+ * Return a unique channel ID. If max is reached, the used_channel_id counter
+ * is returned.
+ */
+uint32_t lsu::registry_session::_get_next_channel_id()
{
- lttng::pthread::lock_guard registry_lock(_lock);
+ if (is_max_channel_id(_used_channel_id)) {
+ return _used_channel_id;
+ }
+
+ _used_channel_id++;
+ return _next_channel_id++;
+}
- const int ret = ust_metadata_session_statedump(this);
- if (ret) {
+void lsu::registry_session::_increase_metadata_size(size_t reservation_length)
+{
+ const auto new_len = _metadata_len + reservation_length;
+ auto new_alloc_len = new_len;
+ const auto old_alloc_len = _metadata_alloc_len;
+
+ /* Rounding the new allocation length to the next power of 2 would overflow. */
+ if (new_alloc_len > (UINT32_MAX >> 1)) {
+ LTTNG_THROW_ERROR(
+ "Failed to reserve trace metadata storage as the new size would overflow");
+ }
+
+ /* The current allocation length is already the largest we can afford. */
+ if ((old_alloc_len << 1) > (UINT32_MAX >> 1)) {
LTTNG_THROW_ERROR(
- "Failed to generate session metadata during registry session creation");
+ "Failed to reserve trace metadata storage as the max size was already reached");
+ }
+
+ if (new_alloc_len > old_alloc_len) {
+ new_alloc_len =
+ std::max<size_t>(1U << get_count_order(new_alloc_len), old_alloc_len << 1);
+
+ auto newptr = (char *) realloc(_metadata, new_alloc_len);
+ if (!newptr) {
+ LTTNG_THROW_POSIX("Failed to allocate trace metadata storage", errno);
+ }
+
+ _metadata = newptr;
+
+ /* We zero directly the memory from start of allocation. */
+ memset(&_metadata[old_alloc_len], 0, new_alloc_len - old_alloc_len);
+ _metadata_alloc_len = new_alloc_len;
+ }
+
+ _metadata_len += reservation_length;
+}
+
+void lsu::registry_session::_append_metadata_fragment(const std::string& fragment)
+{
+ const auto offset = _metadata_len;
+
+ _increase_metadata_size(fragment.size());
+ memcpy(&_metadata[offset], fragment.c_str(), fragment.size());
+
+ if (_metadata_fd >= 0) {
+ const auto bytes_written =
+ lttng_write(_metadata_fd, fragment.c_str(), fragment.size());
+
+ if (bytes_written != fragment.size()) {
+ LTTNG_THROW_POSIX("Failed to write trace metadata fragment to file", errno);
+ }
+ }
+}
+
+void lsu::registry_session::_reset_metadata()
+{
+ _metadata_len_sent = 0;
+ memset(_metadata, 0, _metadata_alloc_len);
+ _metadata_len = 0;
+
+ if (_metadata_fd > 0) {
+ /* Clear the metadata file's content. */
+ clear_metadata_file(_metadata_fd);
+ }
+}
+
+void lsu::registry_session::_generate_metadata()
+{
+ trace_class::accept(*_metadata_generating_visitor);
+}
+
+void lsu::registry_session::regenerate_metadata()
+{
+ lttng::pthread::lock_guard registry_lock(_lock);
+
+ /* Resample the clock */
+ _clock = lttng::make_unique<lsu::clock_class>();
+
+ _metadata_version++;
+ _reset_metadata();
+ _generate_metadata();
+}
+
+/*
+ * Lookup enumeration by enum ID.
+ *
+ * Note that there is no need to lock the registry session as this only
+ * performs an RCU-protected look-up. The function also return an rcu-protected
+ * reference, which ensures that the caller keeps the RCU read lock until it
+ * disposes of the object.
+ */
+lsu::registry_enum::const_rcu_protected_reference
+lsu::registry_session::enumeration(const char *enum_name, uint64_t enum_id) const
+{
+ lsu::registry_enum *reg_enum = nullptr;
+ struct lttng_ht_node_str *node;
+ struct lttng_ht_iter iter;
+ lttng::urcu::unique_read_lock rcu_lock;
+ /*
+ * Hack: only the name is used for hashing; the rest of the attributes
+ * can be fudged.
+ */
+ lsu::registry_signed_enum reg_enum_lookup(enum_name, nullptr, 0);
+
+ ASSERT_RCU_READ_LOCKED();
+
+ reg_enum_lookup.id = enum_id;
+ cds_lfht_lookup(_enums->ht,
+ ht_hash_enum((void *) ®_enum_lookup, lttng_ht_seed),
+ ht_match_enum_id,
+ ®_enum_lookup,
+ &iter.iter);
+ node = lttng_ht_iter_get_node_str(&iter);
+ if (!node) {
+ LTTNG_THROW_PROTOCOL_ERROR(lttng::format(
+ "Unknown enumeration referenced by application event field: enum name = `{}`, enum id = {}",
+ enum_name,
+ enum_id));
+ }
+
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ reg_enum = lttng::utils::container_of(node, &lsu::registry_enum::node);
+ DIAGNOSTIC_POP
+
+ return lsu::registry_enum::const_rcu_protected_reference{ *reg_enum, std::move(rcu_lock) };
+}
+
+/*
+ * Lookup enumeration by name and comparing enumeration entries.
+ * Needs to be called from RCU read-side critical section.
+ */
+lsu::registry_enum *
+lsu::registry_session::_lookup_enum(const lsu::registry_enum *reg_enum_lookup) const
+{
+ lsu::registry_enum *reg_enum = nullptr;
+ struct lttng_ht_node_str *node;
+ struct lttng_ht_iter iter;
+
+ ASSERT_RCU_READ_LOCKED();
+
+ cds_lfht_lookup(_enums->ht,
+ ht_hash_enum((void *) reg_enum_lookup, lttng_ht_seed),
+ ht_match_enum,
+ reg_enum_lookup,
+ &iter.iter);
+ node = lttng_ht_iter_get_node_str(&iter);
+ if (!node) {
+ goto end;
}
+
+ DIAGNOSTIC_PUSH
+ DIAGNOSTIC_IGNORE_INVALID_OFFSETOF
+ reg_enum = lttng::utils::container_of(node, &lsu::registry_enum::node);
+ DIAGNOSTIC_POP
+
+end:
+ return reg_enum;
+}
+
+/*
+ * Create a lsu::registry_enum from the given parameters and add it to the
+ * registry hash table, or find it if already there.
+ *
+ * Should be called with session registry mutex held.
+ *
+ * We receive ownership of entries.
+ */
+void lsu::registry_session::create_or_find_enum(int session_objd,
+ const char *enum_name,
+ struct lttng_ust_ctl_enum_entry *raw_entries,
+ size_t nr_entries,
+ uint64_t *enum_id)
+{
+ struct cds_lfht_node *nodep;
+ lsu::registry_enum *reg_enum = nullptr, *old_reg_enum;
+ lttng::urcu::read_lock_guard read_lock_guard;
+ auto entries = lttng::make_unique_wrapper<lttng_ust_ctl_enum_entry, lttng::memory::free>(
+ raw_entries);
+
+ LTTNG_ASSERT(enum_name);
+
+ /*
+ * This should not happen but since it comes from the UST tracer, an
+ * external party, don't assert and simply validate values.
+ */
+ if (session_objd < 0) {
+ LTTNG_THROW_INVALID_ARGUMENT_ERROR(lttng::format(
+ "Invalid parameters used to create or look-up enumeration from registry session: session_objd = {}",
+ session_objd));
+ }
+ if (nr_entries == 0) {
+ LTTNG_THROW_INVALID_ARGUMENT_ERROR(lttng::format(
+ "Invalid parameters used to create or look-up enumeration from registry session: nr_entries = {}",
+ nr_entries));
+ }
+ if (lttng_strnlen(enum_name, LTTNG_UST_ABI_SYM_NAME_LEN) == LTTNG_UST_ABI_SYM_NAME_LEN) {
+ LTTNG_THROW_INVALID_ARGUMENT_ERROR(
+ "Invalid parameters used to create or look-up enumeration from registry session: enumeration name is not null terminated");
+ }
+
+ if (entries->start.signedness) {
+ reg_enum = new lsu::registry_signed_enum(enum_name, entries.get(), nr_entries);
+ } else {
+ reg_enum = new lsu::registry_unsigned_enum(enum_name, entries.get(), nr_entries);
+ }
+
+ old_reg_enum = _lookup_enum(reg_enum);
+ if (old_reg_enum) {
+ DBG("enum %s already in sess_objd: %u", enum_name, session_objd);
+ /* Fall through. Use prior enum. */
+ destroy_enum(reg_enum);
+ reg_enum = old_reg_enum;
+ } else {
+ DBG("UST registry creating enum: %s, sess_objd: %u", enum_name, session_objd);
+ if (_next_enum_id == -1ULL) {
+ destroy_enum(reg_enum);
+ LTTNG_THROW_ERROR(
+ "Failed to allocate unique enumeration ID as it would overflow");
+ }
+
+ reg_enum->id = _next_enum_id++;
+ nodep = cds_lfht_add_unique(_enums->ht,
+ ht_hash_enum(reg_enum, lttng_ht_seed),
+ ht_match_enum_id,
+ reg_enum,
+ ®_enum->node.node);
+ LTTNG_ASSERT(nodep == ®_enum->node.node);
+ }
+
+ DBG("UST registry reply with enum %s with id %" PRIu64 " in sess_objd: %u",
+ enum_name,
+ reg_enum->id,
+ session_objd);
+ *enum_id = reg_enum->id;
}
projects / lttng-tools.git / blobdiff