/*
+ * lttng.h
+ *
+ * Linux Trace Toolkit Control Library Header File
+ *
* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; only
+ * version 2.1 of the License.
+ *
+ * This library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#ifndef _LIBLTTNGCTL_H
-#define _LIBLTTNGCTL_H
+#ifndef _LTTNG_H
+#define _LTTNG_H
#include <limits.h>
#include <stdint.h>
-#include <uuid/uuid.h>
+#include <sys/types.h>
+
+/* Default unix group name for tracing. */
+#define LTTNG_DEFAULT_TRACING_GROUP "tracing"
-/* Default unix group name for tracing.
+/* Environment variable to set session daemon binary path. */
+#define LTTNG_SESSIOND_PATH_ENV "LTTNG_SESSIOND_PATH"
+
+/* Default trace output directory name */
+#define LTTNG_DEFAULT_TRACE_DIR_NAME "lttng-traces"
+
+/*
+ * Event symbol length. Copied from LTTng kernel ABI.
*/
-#define DEFAULT_TRACING_GROUP "tracing"
+#define LTTNG_SYMBOL_NAME_LEN 128
-/* Environment variable to set session daemon
- * binary path.
+/*
+ * Every lttng_event_* structure both apply to kernel event and user-space
+ * event.
*/
-#define LTTNG_SESSIOND_PATH_ENV "LTTNG_SESSIOND_PATH"
-/* UUID string length (including \0) */
-#define UUID_STR_LEN 37
-/* UUID short string version length (including \0) */
-#define UUID_SHORT_STR_LEN 9
+/*
+ * Domain type are the different possible tracers.
+ */
+enum lttng_domain_type {
+ LTTNG_DOMAIN_KERNEL = 1,
+ LTTNG_DOMAIN_UST = 2,
+ LTTNG_DOMAIN_UST_EXEC_NAME = 3,
+ LTTNG_DOMAIN_UST_PID = 4,
+ LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
+};
-/* Trace type for lttng_trace.
+/*
+ * Instrumentation type of tracing event.
*/
-enum lttng_trace_type {
- KERNEL, USERSPACE,
+enum lttng_event_type {
+ LTTNG_EVENT_ALL = -1,
+ LTTNG_EVENT_TRACEPOINT = 0,
+ LTTNG_EVENT_PROBE = 1,
+ LTTNG_EVENT_FUNCTION = 2,
+ LTTNG_EVENT_FUNCTION_ENTRY = 3,
+ LTTNG_EVENT_NOOP = 4,
+ LTTNG_EVENT_SYSCALL = 5,
};
-/* Simple structure representing a session.
+/*
+ * LTTng consumer mode
*/
-struct lttng_session {
+enum lttng_event_output {
+ LTTNG_EVENT_SPLICE = 0,
+ LTTNG_EVENT_MMAP = 1,
+};
+
+/* Event context possible type */
+enum lttng_event_context_type {
+ LTTNG_EVENT_CONTEXT_PID = 0,
+ LTTNG_EVENT_CONTEXT_PERF_COUNTER = 1,
+ LTTNG_EVENT_CONTEXT_COMM = 2,
+ LTTNG_EVENT_CONTEXT_PRIO = 3,
+ LTTNG_EVENT_CONTEXT_NICE = 4,
+ LTTNG_EVENT_CONTEXT_VPID = 5,
+ LTTNG_EVENT_CONTEXT_TID = 6,
+ LTTNG_EVENT_CONTEXT_VTID = 7,
+ LTTNG_EVENT_CONTEXT_PPID = 8,
+ LTTNG_EVENT_CONTEXT_VPPID = 9,
+};
+
+enum lttng_calibrate_type {
+ LTTNG_CALIBRATE_FUNCTION = 0,
+};
+
+struct lttng_domain {
+ enum lttng_domain_type type;
+ union {
+ pid_t pid;
+ char exec_name[NAME_MAX];
+ } attr;
+};
+
+/* Perf counter attributes */
+struct lttng_event_perf_counter_ctx {
+ uint32_t type;
+ uint64_t config;
+ char name[LTTNG_SYMBOL_NAME_LEN];
+};
+
+/* Event/Channel context */
+struct lttng_event_context {
+ enum lttng_event_context_type ctx;
+ union {
+ struct lttng_event_perf_counter_ctx perf_counter;
+ } u;
+};
+
+/*
+ * Event probe.
+ *
+ * Either addr is used or symbol_name and offset.
+ */
+struct lttng_event_probe_attr {
+ uint64_t addr;
+
+ uint64_t offset;
+ char symbol_name[LTTNG_SYMBOL_NAME_LEN];
+};
+
+/*
+ * Function tracer
+ */
+struct lttng_event_function_attr {
+ char symbol_name[LTTNG_SYMBOL_NAME_LEN];
+};
+
+/*
+ * Generic lttng event
+ */
+struct lttng_event {
+ char name[LTTNG_SYMBOL_NAME_LEN];
+ enum lttng_event_type type;
+ uint32_t enabled;
+ pid_t pid;
+ /* Per event type configuration */
+ union {
+ struct lttng_event_probe_attr probe;
+ struct lttng_event_function_attr ftrace;
+ } attr;
+};
+
+/*
+ * Tracer channel attributes. For both kernel and user-space.
+ */
+struct lttng_channel_attr {
+ int overwrite; /* 1: overwrite, 0: discard */
+ uint64_t subbuf_size; /* bytes */
+ uint64_t num_subbuf; /* power of 2 */
+ unsigned int switch_timer_interval; /* usec */
+ unsigned int read_timer_interval; /* usec */
+ enum lttng_event_output output; /* splice, mmap */
+};
+
+/*
+ * Channel information structure. For both kernel and user-space.
+ */
+struct lttng_channel {
char name[NAME_MAX];
- uuid_t uuid;
+ uint32_t enabled;
+ struct lttng_channel_attr attr;
};
-/* Simple trace representation.
+struct lttng_calibrate {
+ enum lttng_calibrate_type type;
+};
+
+/*
+ * Basic session information.
+ *
+ * This is an 'output data' meaning that it only comes *from* the session
+ * daemon *to* the lttng client. It's basically a 'human' representation of
+ * tracing entities (here a session).
*/
-struct lttng_trace {
+struct lttng_session {
char name[NAME_MAX];
- pid_t pid;
- enum lttng_trace_type type;
+ /* The path where traces are written */
+ char path[PATH_MAX];
+ uint32_t enabled; /* enabled/started: 1, disabled/stopped: 0 */
};
-extern int lttng_create_session(char *name);
-extern int lttng_destroy_session(uuid_t *uuid);
-extern int lttng_connect_sessiond(void);
-extern int lttng_disconnect_sessiond(void);
-extern int lttng_set_tracing_group(const char *name);
-extern int lttng_check_session_daemon(void);
-extern const char *lttng_get_readable_code(int code);
-extern int lttng_ust_list_apps(pid_t **pids);
+/*
+ * Handle used as a context for commands.
+ */
+struct lttng_handle {
+ char session_name[NAME_MAX];
+ struct lttng_domain domain;
+};
+
+/*
+ * Public LTTng control API
+ *
+ * For functions having a lttng domain type as parameter, if a bad value is
+ * given, NO default is applied and an error is returned.
+ *
+ * On success, all functions of the API return 0 or the size of the allocated
+ * array.
+ *
+ * On error, a negative value is returned being a specific lttng-tools error
+ * code which can be humanly interpreted with lttng_strerror(err).
+ */
+
+/*
+ * Create an handle used as a context for every request made to the library.
+ *
+ * This handle contains the session name and lttng domain on which the command
+ * will be executed on.
+ */
+extern struct lttng_handle *lttng_create_handle(const char *session_name,
+ struct lttng_domain *domain);
+
+/*
+ * Destroy an handle. This will simply free(3) the data pointer returned by
+ * lttng_create_handle() and rendering it unsuable.
+ */
+extern void lttng_destroy_handle(struct lttng_handle *handle);
+
+/*
+ * Create tracing session using a name and a path where trace will be written.
+ */
+extern int lttng_create_session(const char *name, const char *path);
+
+/*
+ * Destroy tracing session.
+ *
+ * The session will not be useable anymore, tracing will stopped for all
+ * registered trace and tracing buffers will be flushed.
+ */
+extern int lttng_destroy_session(struct lttng_handle *handle);
+
+/*
+ * List all tracing sessions.
+ *
+ * Return the size of the "lttng_session" array. Caller must free(3).
+ */
extern int lttng_list_sessions(struct lttng_session **sessions);
-extern int lttng_list_traces(uuid_t *uuid, struct lttng_trace **traces);
-extern void lttng_set_current_session_uuid(uuid_t *uuid);
-extern int lttng_ust_create_trace(pid_t pid);
-extern int lttng_ust_start_trace(pid_t pid);
-extern int lttng_ust_stop_trace(pid_t pid);
/*
- * Kernel tracer control
+ * List registered domain(s) of a session.
+ *
+ * Return the size of the "lttng_domain" array. Caller must free(3).
+ */
+extern int lttng_list_domains(struct lttng_handle *handle,
+ struct lttng_domain **domains);
+
+/*
+ * List channel(s) of a session.
+ *
+ * Return the size of the "lttng_channel" array. Caller must free(3).
+ */
+extern int lttng_list_channels(struct lttng_handle *handle,
+ struct lttng_channel **channels);
+
+/*
+ * List event(s) of a session channel.
+ *
+ * Return the size of the "lttng_event" array. Caller must free(3).
+ */
+extern int lttng_list_events(struct lttng_handle *handle,
+ const char *channel_name, struct lttng_event **events);
+
+/*
+ * List available tracepoints of a specific lttng domain.
+ *
+ * Return the size of the "lttng_event" array. Caller must free(3).
+ */
+extern int lttng_list_tracepoints(struct lttng_handle *handle,
+ struct lttng_event **events);
+
+/*
+ * Check if a session daemon is alive.
+ */
+extern int lttng_session_daemon_alive(void);
+
+/*
+ * Set tracing group for the *current* flow of execution.
+ */
+extern int lttng_set_tracing_group(const char *name);
+
+/*
+ * Return a human readable error message of a lttng-tools error code.
+ *
+ * Parameter MUST be a negative value or else you'll get a generic message.
+ */
+extern const char *lttng_strerror(int code);
+
+/*
+ * This call permits to register an "outside consumer" to a session and a lttng
+ * domain. No consumer will be spawned and all fds/commands will go through the
+ * socket path given (socket_path).
+ *
+ * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
+ * command socket. The error socket is not supported yet for roaming consumers.
+ */
+extern int lttng_register_consumer(struct lttng_handle *handle,
+ const char *socket_path);
+
+/*
+ * Start tracing for *all* registered trace (kernel and user-space).
+ */
+extern int lttng_start_tracing(struct lttng_handle *handle);
+
+/*
+ * Stop tracing for *all* registered trace (kernel and user-space).
+ */
+extern int lttng_stop_tracing(struct lttng_handle *handle);
+
+/*
+ * Add context to event for a specific channel.
+ *
+ * If event_name is NULL, the context is applied to all event of the channel.
+ * If channel_name is NULL, a lookup of the event's channel is done.
+ * If both are NULL, the context is applied on all events of all channels.
+ */
+extern int lttng_add_context(struct lttng_handle *handle,
+ struct lttng_event_context *ctx, const char *event_name,
+ const char *channel_name);
+
+/*
+ * Create or enable a kernel event.
+ *
+ * If the event you are trying to enable does not exist, it will be created,
+ * else it is enabled.
+ *
+ * If channel_name is NULL, the default channel is used (channel0).
+ */
+extern int lttng_enable_event(struct lttng_handle *handle,
+ struct lttng_event *ev, const char *channel_name);
+
+/*
+ * Create or enable a kernel channel.
+ *
+ * If name is NULL, the default channel is enabled (channel0).
+ */
+extern int lttng_enable_channel(struct lttng_handle *handle,
+ struct lttng_channel *chan);
+
+/*
+ * Disable kernel event.
+ *
+ * If channel_name is NULL, the default channel is used (channel0).
+ */
+extern int lttng_disable_event(struct lttng_handle *handle,
+ const char *name, const char *channel_name);
+
+/*
+ * Disable kernel channel.
+ *
+ * If channel_name is NULL, the default channel is disabled (channel0).
+ */
+extern int lttng_disable_channel(struct lttng_handle *handle,
+ const char *name);
+
+/*
+ * Calibrate LTTng overhead.
*/
-extern int lttng_kernel_enable_event(char *event_name);
-extern int lttng_kernel_disable_event(char *event_name);
-extern int lttng_kernel_create_session(void);
-extern int lttng_kernel_start_tracing(void);
-extern int lttng_kernel_stop_tracing(void);
-extern int lttng_kernel_create_channel(void);
+extern int lttng_calibrate(struct lttng_handle *handle,
+ struct lttng_calibrate *calibrate);
-#endif /* _LIBLTTNGCTL_H */
+#endif /* _LTTNG_H */
projects / lttng-tools.git / blobdiff