#ifndef _LTT_UST_APP_H
#define _LTT_UST_APP_H
-#include "session.hpp"
+#include "trace-class.hpp"
#include "trace-ust.hpp"
-#include "ust-field-convert.hpp"
-#include "ust-registry-session.hpp"
-#include "ust-registry.hpp"
+#include "ust-field-quirks.hpp"
#include <common/format.hpp>
#include <common/index-allocator.hpp>
+#include <common/reference.hpp>
+#include <common/scope-exit.hpp>
#include <common/uuid.hpp>
+#include <list>
#include <stdint.h>
#define UST_APP_EVENT_LIST_SIZE 32
struct lttng_bytecode;
struct lttng_ust_filter_bytecode;
+namespace lttng {
+namespace sessiond {
+namespace ust {
+class registry_session;
+} /* namespace ust */
+} /* namespace sessiond */
+} /* namespace lttng */
+
extern int the_ust_consumerd64_fd, the_ust_consumerd32_fd;
/*
const char *name;
const struct lttng_bytecode *filter;
enum lttng_ust_abi_loglevel_type loglevel_type;
+ int loglevel_value;
const struct lttng_event_exclusion *exclusion;
};
};
struct ust_app_session {
- /*
- * Lock protecting this session's ust app interaction. Held
- * across command send/recv to/from app. Never nests within the
- * session registry lock.
- */
- pthread_mutex_t lock;
+private:
+ static void _session_unlock(ust_app_session *session)
+ {
+ _const_session_unlock(session);
+ }
- bool enabled;
+ static void _const_session_unlock(const ust_app_session *session)
+ {
+ pthread_mutex_unlock(&session->_lock);
+ }
+
+public:
+ using locked_weak_ref = lttng::non_copyable_reference<
+ ust_app_session,
+ lttng::memory::create_deleter_class<ust_app_session,
+ ust_app_session::_session_unlock>::deleter>;
+ using const_locked_weak_ref = lttng::non_copyable_reference<
+ const ust_app_session,
+ lttng::memory::create_deleter_class<const ust_app_session,
+ ust_app_session::_const_session_unlock>::deleter>;
+
+ static locked_weak_ref make_locked_weak_ref(ust_app_session& ua_session)
+ {
+ return lttng::make_non_copyable_reference<locked_weak_ref::referenced_type,
+ locked_weak_ref::deleter>(ua_session);
+ }
+
+ static const_locked_weak_ref make_locked_weak_ref(const ust_app_session& ua_session)
+ {
+ return lttng::make_non_copyable_reference<const_locked_weak_ref::referenced_type,
+ const_locked_weak_ref::deleter>(
+ ua_session);
+ }
+
+ ust_app_session::const_locked_weak_ref lock() const noexcept
+ {
+ pthread_mutex_lock(&_lock);
+ return ust_app_session::make_locked_weak_ref(*this);
+ }
+
+ ust_app_session::locked_weak_ref lock() noexcept
+ {
+ pthread_mutex_lock(&_lock);
+ return ust_app_session::make_locked_weak_ref(*this);
+ }
+
+ struct identifier {
+ enum class application_abi : std::uint8_t { ABI_32 = 32, ABI_64 = 64 };
+ enum class buffer_allocation_policy : std::uint8_t { PER_PID, PER_UID };
+
+ /* Unique identifier of the ust_app_session. */
+ std::uint64_t id;
+ /* Unique identifier of the ltt_session. */
+ std::uint64_t session_id;
+ /* Credentials of the application which owns the ust_app_session. */
+ lttng_credentials app_credentials;
+ application_abi abi;
+ buffer_allocation_policy allocation_policy;
+ };
+
+ identifier get_identifier() const noexcept
+ {
+ /*
+ * To work around synchro design issues, this method allows the sampling
+ * of a ust_app_session's identifying properties without taking its lock.
+ *
+ * Since those properties are immutable, it is safe to sample them without
+ * holding the lock (as long as the existence of the instance is somehow
+ * guaranteed).
+ *
+ * The locking issue that motivates this method is that the application
+ * notitication handling thread needs to access the registry_session in response to
+ * a message from the application. The ust_app_session's ID is needed to look-up the
+ * registry session.
+ *
+ * The application's message can be emited in response to a command from the
+ * session daemon that is emited by the client thread.
+ *
+ * During that command, the client thread holds the ust_app_session lock until
+ * the application replies to the command. This causes the notification thread
+ * to block when it attempts to sample the ust_app_session's ID properties.
+ */
+ LTTNG_ASSERT(bits_per_long == 32 || bits_per_long == 64);
+ LTTNG_ASSERT(buffer_type == LTTNG_BUFFER_PER_PID ||
+ buffer_type == LTTNG_BUFFER_PER_UID);
+
+ return { .id = id,
+ .session_id = tracing_id,
+ .app_credentials = real_credentials,
+ .abi = bits_per_long == 32 ? identifier::application_abi::ABI_32 :
+ identifier::application_abi::ABI_64,
+ .allocation_policy = buffer_type == LTTNG_BUFFER_PER_PID ?
+ identifier::buffer_allocation_policy::PER_PID :
+ identifier::buffer_allocation_policy::PER_UID };
+ }
+
+ bool enabled = false;
/* started: has the session been in started state at any time ? */
- bool started; /* allows detection of start vs restart. */
- int handle; /* used has unique identifier for app session */
+ bool started = false; /* allows detection of start vs restart. */
+ int handle = 0; /* used has unique identifier for app session */
- bool deleted; /* Session deleted flag. Check with lock held. */
+ bool deleted = false; /* Session deleted flag. Check with lock held. */
/*
* Tracing session ID. Multiple ust app session can have the same tracing
* session id making this value NOT unique to the object.
*/
- uint64_t tracing_id;
- uint64_t id; /* Unique session identifier */
- struct lttng_ht *channels; /* Registered channels */
- struct lttng_ht_node_u64 node;
+ uint64_t tracing_id = 0;
+ uint64_t id = 0; /* Unique session identifier */
+ struct lttng_ht *channels = nullptr; /* Registered channels */
+ struct lttng_ht_node_u64 node = {};
/*
* Node indexed by UST session object descriptor (handle). Stored in the
* ust_sessions_objd hash table in the ust_app object.
*/
- struct lttng_ht_node_ulong ust_objd_node;
+ struct lttng_ht_node_ulong ust_objd_node = {};
/* Starts with 'ust'; no leading slash. */
- char path[PATH_MAX];
+ char path[PATH_MAX] = {};
/* UID/GID of the application owning the session */
- struct lttng_credentials real_credentials;
+ struct lttng_credentials real_credentials = {};
/* Effective UID and GID. Same as the tracing session. */
- struct lttng_credentials effective_credentials;
- struct cds_list_head teardown_node;
+ struct lttng_credentials effective_credentials = {};
/*
* Once at least *one* session is created onto the application, the
* corresponding consumer is set so we can use it on unregistration.
*/
- struct consumer_output *consumer;
- enum lttng_buffer_type buffer_type;
+ struct consumer_output *consumer = nullptr;
+ enum lttng_buffer_type buffer_type = LTTNG_BUFFER_PER_PID;
/* ABI of the session. Same value as the application. */
- uint32_t bits_per_long;
+ uint32_t bits_per_long = 0;
/* For delayed reclaim */
- struct rcu_head rcu_head;
+ struct rcu_head rcu_head = {};
/* If the channel's streams have to be outputed or not. */
- unsigned int output_traces;
- unsigned int live_timer_interval; /* usec */
+ unsigned int output_traces = 0;
+ unsigned int live_timer_interval = 0; /* usec */
/* Metadata channel attributes. */
- struct lttng_ust_ctl_consumer_channel_attr metadata_attr;
+ struct lttng_ust_ctl_consumer_channel_attr metadata_attr = {};
- char root_shm_path[PATH_MAX];
- char shm_path[PATH_MAX];
+ char root_shm_path[PATH_MAX] = {};
+ char shm_path[PATH_MAX] = {};
+
+private:
+ /*
+ * Lock protecting this session's ust app interaction. Held
+ * across command send/recv to/from app. Never nests within the
+ * session registry lock.
+ */
+ mutable pthread_mutex_t _lock = PTHREAD_MUTEX_INITIALIZER;
};
/*
* and a linked list is kept of all running traceable app.
*/
struct ust_app {
+ /*
+ * The lifetime of 'sock' holds a reference to the application; the
+ * application management thread will release a reference to the
+ * application if the application dies.
+ */
+ urcu_ref ref;
+
/* Traffic initiated from the session daemon to the application. */
int sock;
pthread_mutex_t sock_lock; /* Protects sock protocol. */
uint32_t v_minor; /* Version minor number */
/* Extra for the NULL byte. */
char name[UST_APP_PROCNAME_LEN + 1];
- /* Type of buffer this application uses. */
- enum lttng_buffer_type buffer_type;
+
struct lttng_ht *sessions;
struct lttng_ht_node_ulong pid_n;
struct lttng_ht_node_ulong sock_n;
* ht_del of ust_app_session associated to this app. This list is NOT used
* when a session is destroyed.
*/
- struct cds_list_head teardown_head;
+ std::list<ust_app_session *> sessions_to_teardown;
/*
* Hash table containing ust_app_channel indexed by channel objd.
*/
template <>
struct formatter<ust_app> : formatter<std::string> {
template <typename FormatContextType>
- typename FormatContextType::iterator format(const ust_app& app, FormatContextType& ctx)
+ typename FormatContextType::iterator format(const ust_app& app,
+ FormatContextType& ctx) const
{
return format_to(
ctx.out(),
int ust_app_register(struct ust_register_msg *msg, int sock);
int ust_app_register_done(struct ust_app *app);
int ust_app_version(struct ust_app *app);
-void ust_app_unregister(int sock);
+void ust_app_unregister_by_socket(int sock);
int ust_app_start_trace_all(struct ltt_ust_session *usess);
int ust_app_stop_trace_all(struct ltt_ust_session *usess);
int ust_app_destroy_trace_all(struct ltt_ust_session *usess);
void ust_app_add(struct ust_app *app);
struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock);
void ust_app_notify_sock_unregister(int sock);
-ssize_t ust_app_push_metadata(const lttng::sessiond::ust::registry_session::locked_ptr& registry,
- struct consumer_socket *socket,
- int send_zero_data);
-void ust_app_destroy(struct ust_app *app);
+
enum lttng_error_code ust_app_snapshot_record(const struct ltt_ust_session *usess,
const struct consumer_output *output,
uint64_t nb_packets_per_stream);
uint64_t *discarded,
uint64_t *lost);
int ust_app_regenerate_statedump_all(struct ltt_ust_session *usess);
-enum lttng_error_code ust_app_rotate_session(struct ltt_session *session);
enum lttng_error_code ust_app_create_channel_subdirectories(const struct ltt_ust_session *session);
int ust_app_release_object(struct ust_app *app, struct lttng_ust_abi_object_data *data);
-enum lttng_error_code ust_app_clear_session(struct ltt_session *session);
-enum lttng_error_code ust_app_open_packets(struct ltt_session *session);
int ust_app_setup_event_notifier_group(struct ust_app *app);
return 1;
}
+ust_app_session *ust_app_lookup_app_session(const struct ltt_ust_session *usess,
+ const struct ust_app *app);
+lttng::sessiond::ust::registry_session *
+ust_app_get_session_registry(const ust_app_session::identifier& identifier);
+
+lttng_ht *ust_app_get_all();
+
bool ust_app_supports_notifiers(const struct ust_app *app);
bool ust_app_supports_counters(const struct ust_app *app);
+bool ust_app_get(ust_app& app);
+void ust_app_put(ust_app *app);
+
+using ust_app_reference =
+ std::unique_ptr<ust_app, lttng::memory::create_deleter_class<ust_app, ust_app_put>::deleter>;
+
#else /* HAVE_LIBLTTNG_UST_CTL */
static inline int ust_app_destroy_trace_all(struct ltt_ust_session *usess __attribute__((unused)))
return -ENOSYS;
}
-static inline void ust_app_unregister(int sock __attribute__((unused)))
+static inline void ust_app_unregister_by_socket(int sock __attribute__((unused)))
{
}
{
}
-static inline ssize_t ust_app_push_metadata(lttng::sessiond::ust::registry_session *registry
- __attribute__((unused)),
- struct consumer_socket *socket __attribute__((unused)),
- int send_zero_data __attribute__((unused)))
-{
- return 0;
-}
-
-static inline void ust_app_destroy(struct ust_app *app __attribute__((unused)))
-{
- return;
-}
-
static inline enum lttng_error_code
ust_app_snapshot_record(struct ltt_ust_session *usess __attribute__((unused)),
const struct consumer_output *output __attribute__((unused)),
return 0;
}
-static inline enum lttng_error_code ust_app_rotate_session(struct ltt_session *session
- __attribute__((unused)))
+static inline enum lttng_error_code
+ust_app_create_channel_subdirectories(const struct ltt_ust_session *session __attribute__((unused)))
{
return LTTNG_ERR_UNK;
}
-static inline enum lttng_error_code
-ust_app_create_channel_subdirectories(const struct ltt_ust_session *session __attribute__((unused)))
+static inline ust_app_session *ust_app_lookup_app_session(const ltt_ust_session *, const ust_app *)
{
- return LTTNG_ERR_UNK;
+ return nullptr;
+}
+
+static inline lttng::sessiond::ust::registry_session *
+ust_app_get_session_registry(const ust_app_session::identifier&)
+{
+ return nullptr;
+}
+
+static inline lttng_ht *ust_app_get_all()
+{
+ return nullptr;
}
static inline int ust_app_release_object(struct ust_app *app __attribute__((unused)),
return 0;
}
-static inline enum lttng_error_code ust_app_clear_session(struct ltt_session *session
- __attribute__((unused)))
+static inline void ust_app_get(ust_app& app __attribute__((unused)))
{
- return LTTNG_ERR_UNK;
}
-static inline enum lttng_error_code ust_app_open_packets(struct ltt_session *session
- __attribute__((unused)))
+static inline void ust_app_put(ust_app *app __attribute__((unused)))
{
- return LTTNG_ERR_UNK;
}
#endif /* HAVE_LIBLTTNG_UST_CTL */
projects / lttng-tools.git / blobdiff