--- /dev/null
+/*
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * LTTng UST ABI
+ *
+ * Mimic system calls for:
+ * - session creation, returns an object descriptor or failure.
+ * - channel creation, returns an object descriptor or failure.
+ * - Operates on a session object descriptor
+ * - Takes all channel options as parameters.
+ * - stream get, returns an object descriptor or failure.
+ * - Operates on a channel object descriptor.
+ * - stream notifier get, returns an object descriptor or failure.
+ * - Operates on a channel object descriptor.
+ * - event creation, returns an object descriptor or failure.
+ * - Operates on a channel object descriptor
+ * - Takes an event name as parameter
+ * - Takes an instrumentation source as parameter
+ * - e.g. tracepoints, dynamic_probes...
+ * - Takes instrumentation source specific arguments.
+ */
+
+#define _LGPL_SOURCE
+#include <fcntl.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#include <urcu/compiler.h>
+#include <urcu/list.h>
+
+#include <lttng/tracepoint.h>
+#include <lttng/ust-abi.h>
+#include <lttng/ust-error.h>
+#include <lttng/ust-events.h>
+#include <lttng/ust-version.h>
+
+#include "common/ust-fd.h"
+#include "common/logging.h"
+
+#include "common/ringbuffer/frontend_types.h"
+#include "common/ringbuffer/frontend.h"
+#include "common/ringbuffer/shm.h"
+#include "common/counter/counter.h"
+#include "tracepoint-internal.h"
+#include "lttng-tracer.h"
+#include "string-utils.h"
+#include "ust-events-internal.h"
+#include "context-internal.h"
+#include "common/macros.h"
+
+#define OBJ_NAME_LEN 16
+
+static int lttng_ust_abi_close_in_progress;
+
+static
+int lttng_abi_tracepoint_list(void *owner);
+static
+int lttng_abi_tracepoint_field_list(void *owner);
+
+/*
+ * Object descriptor table. Should be protected from concurrent access
+ * by the caller.
+ */
+
+struct lttng_ust_abi_obj {
+ union {
+ struct {
+ void *private_data;
+ const struct lttng_ust_abi_objd_ops *ops;
+ int f_count;
+ int owner_ref; /* has ref from owner */
+ void *owner;
+ char name[OBJ_NAME_LEN];
+ } s;
+ int freelist_next; /* offset freelist. end is -1. */
+ } u;
+};
+
+struct lttng_ust_abi_objd_table {
+ struct lttng_ust_abi_obj *array;
+ unsigned int len, allocated_len;
+ int freelist_head; /* offset freelist head. end is -1 */
+};
+
+static struct lttng_ust_abi_objd_table objd_table = {
+ .freelist_head = -1,
+};
+
+static
+int objd_alloc(void *private_data, const struct lttng_ust_abi_objd_ops *ops,
+ void *owner, const char *name)
+{
+ struct lttng_ust_abi_obj *obj;
+
+ if (objd_table.freelist_head != -1) {
+ obj = &objd_table.array[objd_table.freelist_head];
+ objd_table.freelist_head = obj->u.freelist_next;
+ goto end;
+ }
+
+ if (objd_table.len >= objd_table.allocated_len) {
+ unsigned int new_allocated_len, old_allocated_len;
+ struct lttng_ust_abi_obj *new_table, *old_table;
+
+ old_allocated_len = objd_table.allocated_len;
+ old_table = objd_table.array;
+ if (!old_allocated_len)
+ new_allocated_len = 1;
+ else
+ new_allocated_len = old_allocated_len << 1;
+ new_table = zmalloc(sizeof(struct lttng_ust_abi_obj) * new_allocated_len);
+ if (!new_table)
+ return -ENOMEM;
+ memcpy(new_table, old_table,
+ sizeof(struct lttng_ust_abi_obj) * old_allocated_len);
+ free(old_table);
+ objd_table.array = new_table;
+ objd_table.allocated_len = new_allocated_len;
+ }
+ obj = &objd_table.array[objd_table.len];
+ objd_table.len++;
+end:
+ obj->u.s.private_data = private_data;
+ obj->u.s.ops = ops;
+ obj->u.s.f_count = 2; /* count == 1 : object is allocated */
+ /* count == 2 : allocated + hold ref */
+ obj->u.s.owner_ref = 1; /* One owner reference */
+ obj->u.s.owner = owner;
+ strncpy(obj->u.s.name, name, OBJ_NAME_LEN);
+ obj->u.s.name[OBJ_NAME_LEN - 1] = '\0';
+ return obj - objd_table.array;
+}
+
+static
+struct lttng_ust_abi_obj *_objd_get(int id)
+{
+ if (id >= objd_table.len)
+ return NULL;
+ if (!objd_table.array[id].u.s.f_count)
+ return NULL;
+ return &objd_table.array[id];
+}
+
+static
+void *objd_private(int id)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+ assert(obj);
+ return obj->u.s.private_data;
+}
+
+static
+void objd_set_private(int id, void *private_data)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+ assert(obj);
+ obj->u.s.private_data = private_data;
+}
+
+const struct lttng_ust_abi_objd_ops *lttng_ust_abi_objd_ops(int id)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+
+ if (!obj)
+ return NULL;
+ return obj->u.s.ops;
+}
+
+static
+void objd_free(int id)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+
+ assert(obj);
+ obj->u.freelist_next = objd_table.freelist_head;
+ objd_table.freelist_head = obj - objd_table.array;
+ assert(obj->u.s.f_count == 1);
+ obj->u.s.f_count = 0; /* deallocated */
+}
+
+static
+void objd_ref(int id)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+ assert(obj != NULL);
+ obj->u.s.f_count++;
+}
+
+int lttng_ust_abi_objd_unref(int id, int is_owner)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+
+ if (!obj)
+ return -EINVAL;
+ if (obj->u.s.f_count == 1) {
+ ERR("Reference counting error\n");
+ return -EINVAL;
+ }
+ if (is_owner) {
+ if (!obj->u.s.owner_ref) {
+ ERR("Error decrementing owner reference");
+ return -EINVAL;
+ }
+ obj->u.s.owner_ref--;
+ }
+ if ((--obj->u.s.f_count) == 1) {
+ const struct lttng_ust_abi_objd_ops *ops = lttng_ust_abi_objd_ops(id);
+
+ if (ops->release)
+ ops->release(id);
+ objd_free(id);
+ }
+ return 0;
+}
+
+static
+void objd_table_destroy(void)
+{
+ int i;
+
+ for (i = 0; i < objd_table.allocated_len; i++) {
+ struct lttng_ust_abi_obj *obj;
+
+ obj = _objd_get(i);
+ if (!obj)
+ continue;
+ if (!obj->u.s.owner_ref)
+ continue; /* only unref owner ref. */
+ (void) lttng_ust_abi_objd_unref(i, 1);
+ }
+ free(objd_table.array);
+ objd_table.array = NULL;
+ objd_table.len = 0;
+ objd_table.allocated_len = 0;
+ objd_table.freelist_head = -1;
+}
+
+const char *lttng_ust_obj_get_name(int id)
+{
+ struct lttng_ust_abi_obj *obj = _objd_get(id);
+
+ if (!obj)
+ return NULL;
+ return obj->u.s.name;
+}
+
+void lttng_ust_abi_objd_table_owner_cleanup(void *owner)
+{
+ int i;
+
+ for (i = 0; i < objd_table.allocated_len; i++) {
+ struct lttng_ust_abi_obj *obj;
+
+ obj = _objd_get(i);
+ if (!obj)
+ continue;
+ if (!obj->u.s.owner)
+ continue; /* skip root handles */
+ if (!obj->u.s.owner_ref)
+ continue; /* only unref owner ref. */
+ if (obj->u.s.owner == owner)
+ (void) lttng_ust_abi_objd_unref(i, 1);
+ }
+}
+
+/*
+ * This is LTTng's own personal way to create an ABI for sessiond.
+ * We send commands over a socket.
+ */
+
+static const struct lttng_ust_abi_objd_ops lttng_ops;
+static const struct lttng_ust_abi_objd_ops lttng_event_notifier_group_ops;
+static const struct lttng_ust_abi_objd_ops lttng_session_ops;
+static const struct lttng_ust_abi_objd_ops lttng_channel_ops;
+static const struct lttng_ust_abi_objd_ops lttng_event_enabler_ops;
+static const struct lttng_ust_abi_objd_ops lttng_event_notifier_enabler_ops;
+static const struct lttng_ust_abi_objd_ops lttng_tracepoint_list_ops;
+static const struct lttng_ust_abi_objd_ops lttng_tracepoint_field_list_ops;
+
+int lttng_abi_create_root_handle(void)
+{
+ int root_handle;
+
+ /* root handles have NULL owners */
+ root_handle = objd_alloc(NULL, <tng_ops, NULL, "root");
+ return root_handle;
+}
+
+static
+int lttng_is_channel_ready(struct lttng_ust_channel_buffer *lttng_chan)
+{
+ struct lttng_ust_lib_ring_buffer_channel *chan;
+ unsigned int nr_streams, exp_streams;
+
+ chan = lttng_chan->priv->rb_chan;
+ nr_streams = channel_handle_get_nr_streams(lttng_chan->priv->rb_chan->handle);
+ exp_streams = chan->nr_streams;
+ return nr_streams == exp_streams;
+}
+
+static
+int lttng_abi_create_session(void *owner)
+{
+ struct lttng_ust_session *session;
+ int session_objd, ret;
+
+ session = lttng_session_create();
+ if (!session)
+ return -ENOMEM;
+ session_objd = objd_alloc(session, <tng_session_ops, owner, "session");
+ if (session_objd < 0) {
+ ret = session_objd;
+ goto objd_error;
+ }
+ session->priv->objd = session_objd;
+ session->priv->owner = owner;
+ return session_objd;
+
+objd_error:
+ lttng_session_destroy(session);
+ return ret;
+}
+
+static
+long lttng_abi_tracer_version(int objd __attribute__((unused)),
+ struct lttng_ust_abi_tracer_version *v)
+{
+ v->major = LTTNG_UST_MAJOR_VERSION;
+ v->minor = LTTNG_UST_MINOR_VERSION;
+ v->patchlevel = LTTNG_UST_PATCHLEVEL_VERSION;
+ return 0;
+}
+
+static
+int lttng_abi_event_notifier_send_fd(void *owner, int *event_notifier_notif_fd)
+{
+ struct lttng_event_notifier_group *event_notifier_group;
+ int event_notifier_group_objd, ret, fd_flag;
+
+ event_notifier_group = lttng_event_notifier_group_create();
+ if (!event_notifier_group)
+ return -ENOMEM;
+
+ /*
+ * Set this file descriptor as NON-BLOCKING.
+ */
+ fd_flag = fcntl(*event_notifier_notif_fd, F_GETFL);
+
+ fd_flag |= O_NONBLOCK;
+
+ ret = fcntl(*event_notifier_notif_fd, F_SETFL, fd_flag);
+ if (ret) {
+ ret = -errno;
+ goto fd_error;
+ }
+
+ event_notifier_group_objd = objd_alloc(event_notifier_group,
+ <tng_event_notifier_group_ops, owner, "event_notifier_group");
+ if (event_notifier_group_objd < 0) {
+ ret = event_notifier_group_objd;
+ goto objd_error;
+ }
+
+ event_notifier_group->objd = event_notifier_group_objd;
+ event_notifier_group->owner = owner;
+ event_notifier_group->notification_fd = *event_notifier_notif_fd;
+ /* Object descriptor takes ownership of notification fd. */
+ *event_notifier_notif_fd = -1;
+
+ return event_notifier_group_objd;
+
+objd_error:
+ lttng_event_notifier_group_destroy(event_notifier_group);
+fd_error:
+ return ret;
+}
+
+static
+long lttng_abi_add_context(int objd __attribute__((unused)),
+ struct lttng_ust_abi_context *context_param,
+ union lttng_ust_abi_args *uargs,
+ struct lttng_ust_ctx **ctx, struct lttng_ust_session *session)
+{
+ return lttng_attach_context(context_param, uargs, ctx, session);
+}
+
+/**
+ * lttng_cmd - lttng control through socket commands
+ *
+ * @objd: the object descriptor
+ * @cmd: the command
+ * @arg: command arg
+ * @uargs: UST arguments (internal)
+ * @owner: objd owner
+ *
+ * This descriptor implements lttng commands:
+ * LTTNG_UST_ABI_SESSION
+ * Returns a LTTng trace session object descriptor
+ * LTTNG_UST_ABI_TRACER_VERSION
+ * Returns the LTTng kernel tracer version
+ * LTTNG_UST_ABI_TRACEPOINT_LIST
+ * Returns a file descriptor listing available tracepoints
+ * LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST
+ * Returns a file descriptor listing available tracepoint fields
+ * LTTNG_UST_ABI_WAIT_QUIESCENT
+ * Returns after all previously running probes have completed
+ *
+ * The returned session will be deleted when its file descriptor is closed.
+ */
+static
+long lttng_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs, void *owner)
+{
+ switch (cmd) {
+ case LTTNG_UST_ABI_SESSION:
+ return lttng_abi_create_session(owner);
+ case LTTNG_UST_ABI_TRACER_VERSION:
+ return lttng_abi_tracer_version(objd,
+ (struct lttng_ust_abi_tracer_version *) arg);
+ case LTTNG_UST_ABI_TRACEPOINT_LIST:
+ return lttng_abi_tracepoint_list(owner);
+ case LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST:
+ return lttng_abi_tracepoint_field_list(owner);
+ case LTTNG_UST_ABI_WAIT_QUIESCENT:
+ lttng_ust_urcu_synchronize_rcu();
+ return 0;
+ case LTTNG_UST_ABI_EVENT_NOTIFIER_GROUP_CREATE:
+ return lttng_abi_event_notifier_send_fd(owner,
+ &uargs->event_notifier_handle.event_notifier_notif_fd);
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_ops = {
+ .cmd = lttng_cmd,
+};
+
+static
+int lttng_abi_map_channel(int session_objd,
+ struct lttng_ust_abi_channel *ust_chan,
+ union lttng_ust_abi_args *uargs,
+ void *owner)
+{
+ struct lttng_ust_session *session = objd_private(session_objd);
+ const char *transport_name;
+ struct lttng_transport *transport;
+ const char *chan_name;
+ int chan_objd;
+ struct lttng_ust_shm_handle *channel_handle;
+ struct lttng_ust_abi_channel_config *lttng_chan_config;
+ struct lttng_ust_channel_buffer *lttng_chan_buf;
+ struct lttng_ust_lib_ring_buffer_channel *chan;
+ struct lttng_ust_lib_ring_buffer_config *config;
+ void *chan_data;
+ int wakeup_fd;
+ uint64_t len;
+ int ret;
+ enum lttng_ust_abi_chan_type type;
+
+ chan_data = uargs->channel.chan_data;
+ wakeup_fd = uargs->channel.wakeup_fd;
+ len = ust_chan->len;
+ type = ust_chan->type;
+
+ switch (type) {
+ case LTTNG_UST_ABI_CHAN_PER_CPU:
+ break;
+ default:
+ ret = -EINVAL;
+ goto invalid;
+ }
+
+ if (session->priv->been_active) {
+ ret = -EBUSY;
+ goto active; /* Refuse to add channel to active session */
+ }
+
+ lttng_chan_buf = lttng_ust_alloc_channel_buffer();
+ if (!lttng_chan_buf) {
+ ret = -ENOMEM;
+ goto lttng_chan_buf_error;
+ }
+
+ channel_handle = channel_handle_create(chan_data, len, wakeup_fd);
+ if (!channel_handle) {
+ ret = -EINVAL;
+ goto handle_error;
+ }
+
+ /* Ownership of chan_data and wakeup_fd taken by channel handle. */
+ uargs->channel.chan_data = NULL;
+ uargs->channel.wakeup_fd = -1;
+
+ chan = shmp(channel_handle, channel_handle->chan);
+ assert(chan);
+ chan->handle = channel_handle;
+ config = &chan->backend.config;
+ lttng_chan_config = channel_get_private_config(chan);
+ if (!lttng_chan_config) {
+ ret = -EINVAL;
+ goto alloc_error;
+ }
+
+ if (lttng_ust_session_uuid_validate(session, lttng_chan_config->uuid)) {
+ ret = -EINVAL;
+ goto uuid_error;
+ }
+
+ /* Lookup transport name */
+ switch (type) {
+ case LTTNG_UST_ABI_CHAN_PER_CPU:
+ if (config->output == RING_BUFFER_MMAP) {
+ if (config->mode == RING_BUFFER_OVERWRITE) {
+ if (config->wakeup == RING_BUFFER_WAKEUP_BY_WRITER) {
+ transport_name = "relay-overwrite-mmap";
+ } else {
+ transport_name = "relay-overwrite-rt-mmap";
+ }
+ } else {
+ if (config->wakeup == RING_BUFFER_WAKEUP_BY_WRITER) {
+ transport_name = "relay-discard-mmap";
+ } else {
+ transport_name = "relay-discard-rt-mmap";
+ }
+ }
+ } else {
+ ret = -EINVAL;
+ goto notransport;
+ }
+ chan_name = "channel";
+ break;
+ default:
+ ret = -EINVAL;
+ goto notransport;
+ }
+ transport = lttng_ust_transport_find(transport_name);
+ if (!transport) {
+ DBG("LTTng transport %s not found\n",
+ transport_name);
+ ret = -EINVAL;
+ goto notransport;
+ }
+
+ chan_objd = objd_alloc(NULL, <tng_channel_ops, owner, chan_name);
+ if (chan_objd < 0) {
+ ret = chan_objd;
+ goto objd_error;
+ }
+
+ /* Initialize our lttng chan */
+ lttng_chan_buf->parent->enabled = 1;
+ lttng_chan_buf->parent->session = session;
+
+ lttng_chan_buf->priv->parent.tstate = 1;
+ lttng_chan_buf->priv->ctx = NULL;
+ lttng_chan_buf->priv->rb_chan = chan;
+
+ lttng_chan_buf->ops = &transport->ops;
+
+ memcpy(&chan->backend.config,
+ transport->client_config,
+ sizeof(chan->backend.config));
+ cds_list_add(<tng_chan_buf->priv->node, &session->priv->chan_head);
+ lttng_chan_buf->priv->header_type = 0;
+ lttng_chan_buf->priv->type = type;
+ /* Copy fields from lttng ust chan config. */
+ lttng_chan_buf->priv->id = lttng_chan_config->id;
+ memcpy(lttng_chan_buf->priv->uuid, lttng_chan_config->uuid, LTTNG_UST_UUID_LEN);
+ channel_set_private(chan, lttng_chan_buf);
+
+ /*
+ * We tolerate no failure path after channel creation. It will stay
+ * invariant for the rest of the session.
+ */
+ objd_set_private(chan_objd, lttng_chan_buf);
+ lttng_chan_buf->priv->parent.objd = chan_objd;
+ /* The channel created holds a reference on the session */
+ objd_ref(session_objd);
+ return chan_objd;
+
+ /* error path after channel was created */
+objd_error:
+notransport:
+uuid_error:
+alloc_error:
+ channel_destroy(chan, channel_handle, 0);
+ lttng_ust_free_channel_common(lttng_chan_buf->parent);
+ return ret;
+
+handle_error:
+ lttng_ust_free_channel_common(lttng_chan_buf->parent);
+lttng_chan_buf_error:
+active:
+invalid:
+ return ret;
+}
+
+/**
+ * lttng_session_cmd - lttng session object command
+ *
+ * @obj: the object
+ * @cmd: the command
+ * @arg: command arg
+ * @uargs: UST arguments (internal)
+ * @owner: objd owner
+ *
+ * This descriptor implements lttng commands:
+ * LTTNG_UST_ABI_CHANNEL
+ * Returns a LTTng channel object descriptor
+ * LTTNG_UST_ABI_ENABLE
+ * Enables tracing for a session (weak enable)
+ * LTTNG_UST_ABI_DISABLE
+ * Disables tracing for a session (strong disable)
+ *
+ * The returned channel will be deleted when its file descriptor is closed.
+ */
+static
+long lttng_session_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs, void *owner)
+{
+ struct lttng_ust_session *session = objd_private(objd);
+
+ switch (cmd) {
+ case LTTNG_UST_ABI_CHANNEL:
+ return lttng_abi_map_channel(objd,
+ (struct lttng_ust_abi_channel *) arg,
+ uargs, owner);
+ case LTTNG_UST_ABI_SESSION_START:
+ case LTTNG_UST_ABI_ENABLE:
+ return lttng_session_enable(session);
+ case LTTNG_UST_ABI_SESSION_STOP:
+ case LTTNG_UST_ABI_DISABLE:
+ return lttng_session_disable(session);
+ case LTTNG_UST_ABI_SESSION_STATEDUMP:
+ return lttng_session_statedump(session);
+ case LTTNG_UST_ABI_COUNTER:
+ case LTTNG_UST_ABI_COUNTER_GLOBAL:
+ case LTTNG_UST_ABI_COUNTER_CPU:
+ /* Not implemented yet. */
+ return -EINVAL;
+ default:
+ return -EINVAL;
+ }
+}
+
+/*
+ * Called when the last file reference is dropped.
+ *
+ * Big fat note: channels and events are invariant for the whole session after
+ * their creation. So this session destruction also destroys all channel and
+ * event structures specific to this session (they are not destroyed when their
+ * individual file is released).
+ */
+static
+int lttng_release_session(int objd)
+{
+ struct lttng_ust_session *session = objd_private(objd);
+
+ if (session) {
+ lttng_session_destroy(session);
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_session_ops = {
+ .release = lttng_release_session,
+ .cmd = lttng_session_cmd,
+};
+
+static int lttng_ust_event_notifier_enabler_create(int event_notifier_group_obj,
+ void *owner, struct lttng_ust_abi_event_notifier *event_notifier_param,
+ enum lttng_enabler_format_type type)
+{
+ struct lttng_event_notifier_group *event_notifier_group =
+ objd_private(event_notifier_group_obj);
+ struct lttng_event_notifier_enabler *event_notifier_enabler;
+ int event_notifier_objd, ret;
+
+ event_notifier_param->event.name[LTTNG_UST_ABI_SYM_NAME_LEN - 1] = '\0';
+ event_notifier_objd = objd_alloc(NULL, <tng_event_notifier_enabler_ops, owner,
+ "event_notifier enabler");
+ if (event_notifier_objd < 0) {
+ ret = event_notifier_objd;
+ goto objd_error;
+ }
+
+ event_notifier_enabler = lttng_event_notifier_enabler_create(
+ event_notifier_group, type, event_notifier_param);
+ if (!event_notifier_enabler) {
+ ret = -ENOMEM;
+ goto event_notifier_error;
+ }
+
+ objd_set_private(event_notifier_objd, event_notifier_enabler);
+ /* The event_notifier holds a reference on the event_notifier group. */
+ objd_ref(event_notifier_enabler->group->objd);
+
+ return event_notifier_objd;
+
+event_notifier_error:
+ {
+ int err;
+
+ err = lttng_ust_abi_objd_unref(event_notifier_objd, 1);
+ assert(!err);
+ }
+objd_error:
+ return ret;
+}
+
+static
+long lttng_event_notifier_enabler_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs __attribute__((unused)),
+ void *owner __attribute__((unused)))
+{
+ struct lttng_event_notifier_enabler *event_notifier_enabler = objd_private(objd);
+ switch (cmd) {
+ case LTTNG_UST_ABI_FILTER:
+ return lttng_event_notifier_enabler_attach_filter_bytecode(
+ event_notifier_enabler,
+ (struct lttng_ust_bytecode_node **) arg);
+ case LTTNG_UST_ABI_EXCLUSION:
+ return lttng_event_notifier_enabler_attach_exclusion(event_notifier_enabler,
+ (struct lttng_ust_excluder_node **) arg);
+ case LTTNG_UST_ABI_CAPTURE:
+ return lttng_event_notifier_enabler_attach_capture_bytecode(
+ event_notifier_enabler,
+ (struct lttng_ust_bytecode_node **) arg);
+ case LTTNG_UST_ABI_ENABLE:
+ return lttng_event_notifier_enabler_enable(event_notifier_enabler);
+ case LTTNG_UST_ABI_DISABLE:
+ return lttng_event_notifier_enabler_disable(event_notifier_enabler);
+ default:
+ return -EINVAL;
+ }
+}
+
+/**
+ * lttng_event_notifier_group_error_counter_cmd - lttng event_notifier group error counter object command
+ *
+ * @obj: the object
+ * @cmd: the command
+ * @arg: command arg
+ * @uargs: UST arguments (internal)
+ * @owner: objd owner
+ *
+ * This descriptor implements lttng commands:
+ * LTTNG_UST_ABI_COUNTER_GLOBAL
+ * Return negative error code on error, 0 on success.
+ * LTTNG_UST_ABI_COUNTER_CPU
+ * Return negative error code on error, 0 on success.
+ */
+static
+long lttng_event_notifier_group_error_counter_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs, void *owner __attribute__((unused)))
+{
+ int ret;
+ struct lttng_counter *counter = objd_private(objd);
+
+ switch (cmd) {
+ case LTTNG_UST_ABI_COUNTER_GLOBAL:
+ ret = -EINVAL; /* Unimplemented. */
+ break;
+ case LTTNG_UST_ABI_COUNTER_CPU:
+ {
+ struct lttng_ust_abi_counter_cpu *counter_cpu =
+ (struct lttng_ust_abi_counter_cpu *)arg;
+
+ ret = lttng_counter_set_cpu_shm(counter->counter,
+ counter_cpu->cpu_nr, uargs->counter_shm.shm_fd);
+ if (!ret) {
+ /* Take ownership of the shm_fd. */
+ uargs->counter_shm.shm_fd = -1;
+ }
+ break;
+ }
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+int lttng_release_event_notifier_group_error_counter(int objd)
+ __attribute__((visibility("hidden")));
+int lttng_release_event_notifier_group_error_counter(int objd)
+{
+ struct lttng_counter *counter = objd_private(objd);
+
+ if (counter) {
+ return lttng_ust_abi_objd_unref(counter->event_notifier_group->objd, 0);
+ } else {
+ return -EINVAL;
+ }
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_event_notifier_group_error_counter_ops = {
+ .release = lttng_release_event_notifier_group_error_counter,
+ .cmd = lttng_event_notifier_group_error_counter_cmd,
+};
+
+static
+int lttng_ust_event_notifier_group_create_error_counter(int event_notifier_group_objd, void *owner,
+ struct lttng_ust_abi_counter_conf *error_counter_conf)
+{
+ const char *counter_transport_name;
+ struct lttng_event_notifier_group *event_notifier_group =
+ objd_private(event_notifier_group_objd);
+ struct lttng_counter *counter;
+ int counter_objd, ret;
+ struct lttng_counter_dimension dimensions[1];
+ size_t counter_len;
+
+ if (event_notifier_group->error_counter)
+ return -EBUSY;
+
+ if (error_counter_conf->arithmetic != LTTNG_UST_ABI_COUNTER_ARITHMETIC_MODULAR)
+ return -EINVAL;
+
+ if (error_counter_conf->number_dimensions != 1)
+ return -EINVAL;
+
+ switch (error_counter_conf->bitness) {
+ case LTTNG_UST_ABI_COUNTER_BITNESS_64:
+ counter_transport_name = "counter-per-cpu-64-modular";
+ break;
+ case LTTNG_UST_ABI_COUNTER_BITNESS_32:
+ counter_transport_name = "counter-per-cpu-32-modular";
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ counter_objd = objd_alloc(NULL, <tng_event_notifier_group_error_counter_ops, owner,
+ "event_notifier group error counter");
+ if (counter_objd < 0) {
+ ret = counter_objd;
+ goto objd_error;
+ }
+
+ counter_len = error_counter_conf->dimensions[0].size;
+ dimensions[0].size = counter_len;
+ dimensions[0].underflow_index = 0;
+ dimensions[0].overflow_index = 0;
+ dimensions[0].has_underflow = 0;
+ dimensions[0].has_overflow = 0;
+
+ counter = lttng_ust_counter_create(counter_transport_name, 1, dimensions);
+ if (!counter) {
+ ret = -EINVAL;
+ goto create_error;
+ }
+
+ event_notifier_group->error_counter_len = counter_len;
+ /*
+ * store-release to publish error counter matches load-acquire
+ * in record_error. Ensures the counter is created and the
+ * error_counter_len is set before they are used.
+ * Currently a full memory barrier is used, which could be
+ * turned into acquire-release barriers.
+ */
+ cmm_smp_mb();
+ CMM_STORE_SHARED(event_notifier_group->error_counter, counter);
+
+ counter->objd = counter_objd;
+ counter->event_notifier_group = event_notifier_group; /* owner */
+
+ objd_set_private(counter_objd, counter);
+ /* The error counter holds a reference on the event_notifier group. */
+ objd_ref(event_notifier_group->objd);
+
+ return counter_objd;
+
+create_error:
+ {
+ int err;
+
+ err = lttng_ust_abi_objd_unref(counter_objd, 1);
+ assert(!err);
+ }
+objd_error:
+ return ret;
+}
+
+static
+long lttng_event_notifier_group_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs, void *owner)
+{
+ switch (cmd) {
+ case LTTNG_UST_ABI_EVENT_NOTIFIER_CREATE:
+ {
+ struct lttng_ust_abi_event_notifier *event_notifier_param =
+ (struct lttng_ust_abi_event_notifier *) arg;
+ if (strutils_is_star_glob_pattern(event_notifier_param->event.name)) {
+ /*
+ * If the event name is a star globbing pattern,
+ * we create the special star globbing enabler.
+ */
+ return lttng_ust_event_notifier_enabler_create(objd,
+ owner, event_notifier_param,
+ LTTNG_ENABLER_FORMAT_STAR_GLOB);
+ } else {
+ return lttng_ust_event_notifier_enabler_create(objd,
+ owner, event_notifier_param,
+ LTTNG_ENABLER_FORMAT_EVENT);
+ }
+ }
+ case LTTNG_UST_ABI_COUNTER:
+ {
+ struct lttng_ust_abi_counter_conf *counter_conf =
+ (struct lttng_ust_abi_counter_conf *) uargs->counter.counter_data;
+ return lttng_ust_event_notifier_group_create_error_counter(
+ objd, owner, counter_conf);
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int lttng_event_notifier_enabler_release(int objd)
+{
+ struct lttng_event_notifier_enabler *event_notifier_enabler = objd_private(objd);
+
+ if (event_notifier_enabler)
+ return lttng_ust_abi_objd_unref(event_notifier_enabler->group->objd, 0);
+ return 0;
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_event_notifier_enabler_ops = {
+ .release = lttng_event_notifier_enabler_release,
+ .cmd = lttng_event_notifier_enabler_cmd,
+};
+
+static
+int lttng_release_event_notifier_group(int objd)
+{
+ struct lttng_event_notifier_group *event_notifier_group = objd_private(objd);
+
+ if (event_notifier_group) {
+ lttng_event_notifier_group_destroy(event_notifier_group);
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_event_notifier_group_ops = {
+ .release = lttng_release_event_notifier_group,
+ .cmd = lttng_event_notifier_group_cmd,
+};
+
+static
+long lttng_tracepoint_list_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs __attribute__((unused)),
+ void *owner __attribute__((unused)))
+{
+ struct lttng_ust_tracepoint_list *list = objd_private(objd);
+ struct lttng_ust_abi_tracepoint_iter *tp =
+ (struct lttng_ust_abi_tracepoint_iter *) arg;
+ struct lttng_ust_abi_tracepoint_iter *iter;
+
+ switch (cmd) {
+ case LTTNG_UST_ABI_TRACEPOINT_LIST_GET:
+ {
+ iter = lttng_ust_tracepoint_list_get_iter_next(list);
+ if (!iter)
+ return -LTTNG_UST_ERR_NOENT;
+ memcpy(tp, iter, sizeof(*tp));
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int lttng_abi_tracepoint_list(void *owner)
+{
+ int list_objd, ret;
+ struct lttng_ust_tracepoint_list *list;
+
+ list_objd = objd_alloc(NULL, <tng_tracepoint_list_ops, owner, "tp_list");
+ if (list_objd < 0) {
+ ret = list_objd;
+ goto objd_error;
+ }
+ list = zmalloc(sizeof(*list));
+ if (!list) {
+ ret = -ENOMEM;
+ goto alloc_error;
+ }
+ objd_set_private(list_objd, list);
+
+ /* populate list by walking on all registered probes. */
+ ret = lttng_probes_get_event_list(list);
+ if (ret) {
+ goto list_error;
+ }
+ return list_objd;
+
+list_error:
+ free(list);
+alloc_error:
+ {
+ int err;
+
+ err = lttng_ust_abi_objd_unref(list_objd, 1);
+ assert(!err);
+ }
+objd_error:
+ return ret;
+}
+
+static
+int lttng_release_tracepoint_list(int objd)
+{
+ struct lttng_ust_tracepoint_list *list = objd_private(objd);
+
+ if (list) {
+ lttng_probes_prune_event_list(list);
+ free(list);
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_tracepoint_list_ops = {
+ .release = lttng_release_tracepoint_list,
+ .cmd = lttng_tracepoint_list_cmd,
+};
+
+static
+long lttng_tracepoint_field_list_cmd(int objd, unsigned int cmd,
+ unsigned long arg __attribute__((unused)), union lttng_ust_abi_args *uargs,
+ void *owner __attribute__((unused)))
+{
+ struct lttng_ust_field_list *list = objd_private(objd);
+ struct lttng_ust_abi_field_iter *tp = &uargs->field_list.entry;
+ struct lttng_ust_abi_field_iter *iter;
+
+ switch (cmd) {
+ case LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST_GET:
+ {
+ iter = lttng_ust_field_list_get_iter_next(list);
+ if (!iter)
+ return -LTTNG_UST_ERR_NOENT;
+ memcpy(tp, iter, sizeof(*tp));
+ return 0;
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int lttng_abi_tracepoint_field_list(void *owner)
+{
+ int list_objd, ret;
+ struct lttng_ust_field_list *list;
+
+ list_objd = objd_alloc(NULL, <tng_tracepoint_field_list_ops, owner,
+ "tp_field_list");
+ if (list_objd < 0) {
+ ret = list_objd;
+ goto objd_error;
+ }
+ list = zmalloc(sizeof(*list));
+ if (!list) {
+ ret = -ENOMEM;
+ goto alloc_error;
+ }
+ objd_set_private(list_objd, list);
+
+ /* populate list by walking on all registered probes. */
+ ret = lttng_probes_get_field_list(list);
+ if (ret) {
+ goto list_error;
+ }
+ return list_objd;
+
+list_error:
+ free(list);
+alloc_error:
+ {
+ int err;
+
+ err = lttng_ust_abi_objd_unref(list_objd, 1);
+ assert(!err);
+ }
+objd_error:
+ return ret;
+}
+
+static
+int lttng_release_tracepoint_field_list(int objd)
+{
+ struct lttng_ust_field_list *list = objd_private(objd);
+
+ if (list) {
+ lttng_probes_prune_field_list(list);
+ free(list);
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_tracepoint_field_list_ops = {
+ .release = lttng_release_tracepoint_field_list,
+ .cmd = lttng_tracepoint_field_list_cmd,
+};
+
+static
+int lttng_abi_map_stream(int channel_objd, struct lttng_ust_abi_stream *info,
+ union lttng_ust_abi_args *uargs, void *owner __attribute__((unused)))
+{
+ struct lttng_ust_channel_buffer *lttng_chan_buf = objd_private(channel_objd);
+ int ret;
+
+ ret = channel_handle_add_stream(lttng_chan_buf->priv->rb_chan->handle,
+ uargs->stream.shm_fd, uargs->stream.wakeup_fd,
+ info->stream_nr, info->len);
+ if (ret)
+ goto error_add_stream;
+ /* Take ownership of shm_fd and wakeup_fd. */
+ uargs->stream.shm_fd = -1;
+ uargs->stream.wakeup_fd = -1;
+
+ return 0;
+
+error_add_stream:
+ return ret;
+}
+
+static
+int lttng_abi_create_event_enabler(int channel_objd,
+ struct lttng_ust_abi_event *event_param,
+ void *owner,
+ enum lttng_enabler_format_type format_type)
+{
+ struct lttng_ust_channel_buffer *channel = objd_private(channel_objd);
+ struct lttng_event_enabler *enabler;
+ int event_objd, ret;
+
+ event_param->name[LTTNG_UST_ABI_SYM_NAME_LEN - 1] = '\0';
+ event_objd = objd_alloc(NULL, <tng_event_enabler_ops, owner,
+ "event enabler");
+ if (event_objd < 0) {
+ ret = event_objd;
+ goto objd_error;
+ }
+ /*
+ * We tolerate no failure path after event creation. It will stay
+ * invariant for the rest of the session.
+ */
+ enabler = lttng_event_enabler_create(format_type, event_param, channel);
+ if (!enabler) {
+ ret = -ENOMEM;
+ goto event_error;
+ }
+ objd_set_private(event_objd, enabler);
+ /* The event holds a reference on the channel */
+ objd_ref(channel_objd);
+ return event_objd;
+
+event_error:
+ {
+ int err;
+
+ err = lttng_ust_abi_objd_unref(event_objd, 1);
+ assert(!err);
+ }
+objd_error:
+ return ret;
+}
+
+/**
+ * lttng_channel_cmd - lttng control through object descriptors
+ *
+ * @objd: the object descriptor
+ * @cmd: the command
+ * @arg: command arg
+ * @uargs: UST arguments (internal)
+ * @owner: objd owner
+ *
+ * This object descriptor implements lttng commands:
+ * LTTNG_UST_ABI_STREAM
+ * Returns an event stream object descriptor or failure.
+ * (typically, one event stream records events from one CPU)
+ * LTTNG_UST_ABI_EVENT
+ * Returns an event object descriptor or failure.
+ * LTTNG_UST_ABI_CONTEXT
+ * Prepend a context field to each event in the channel
+ * LTTNG_UST_ABI_ENABLE
+ * Enable recording for events in this channel (weak enable)
+ * LTTNG_UST_ABI_DISABLE
+ * Disable recording for events in this channel (strong disable)
+ *
+ * Channel and event file descriptors also hold a reference on the session.
+ */
+static
+long lttng_channel_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs, void *owner)
+{
+ struct lttng_ust_channel_buffer *lttng_chan_buf = objd_private(objd);
+
+ if (cmd != LTTNG_UST_ABI_STREAM) {
+ /*
+ * Check if channel received all streams.
+ */
+ if (!lttng_is_channel_ready(lttng_chan_buf))
+ return -EPERM;
+ }
+
+ switch (cmd) {
+ case LTTNG_UST_ABI_STREAM:
+ {
+ struct lttng_ust_abi_stream *stream;
+
+ stream = (struct lttng_ust_abi_stream *) arg;
+ /* stream used as output */
+ return lttng_abi_map_stream(objd, stream, uargs, owner);
+ }
+ case LTTNG_UST_ABI_EVENT:
+ {
+ struct lttng_ust_abi_event *event_param =
+ (struct lttng_ust_abi_event *) arg;
+
+ if (strutils_is_star_glob_pattern(event_param->name)) {
+ /*
+ * If the event name is a star globbing pattern,
+ * we create the special star globbing enabler.
+ */
+ return lttng_abi_create_event_enabler(objd, event_param,
+ owner, LTTNG_ENABLER_FORMAT_STAR_GLOB);
+ } else {
+ return lttng_abi_create_event_enabler(objd, event_param,
+ owner, LTTNG_ENABLER_FORMAT_EVENT);
+ }
+ }
+ case LTTNG_UST_ABI_CONTEXT:
+ return lttng_abi_add_context(objd,
+ (struct lttng_ust_abi_context *) arg, uargs,
+ <tng_chan_buf->priv->ctx,
+ lttng_chan_buf->parent->session);
+ case LTTNG_UST_ABI_ENABLE:
+ return lttng_channel_enable(lttng_chan_buf->parent);
+ case LTTNG_UST_ABI_DISABLE:
+ return lttng_channel_disable(lttng_chan_buf->parent);
+ case LTTNG_UST_ABI_FLUSH_BUFFER:
+ return lttng_chan_buf->ops->priv->flush_buffer(lttng_chan_buf);
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int lttng_channel_release(int objd)
+{
+ struct lttng_ust_channel_buffer *lttng_chan_buf = objd_private(objd);
+
+ if (lttng_chan_buf)
+ return lttng_ust_abi_objd_unref(lttng_chan_buf->parent->session->priv->objd, 0);
+ return 0;
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_channel_ops = {
+ .release = lttng_channel_release,
+ .cmd = lttng_channel_cmd,
+};
+
+/**
+ * lttng_enabler_cmd - lttng control through object descriptors
+ *
+ * @objd: the object descriptor
+ * @cmd: the command
+ * @arg: command arg
+ * @uargs: UST arguments (internal)
+ * @owner: objd owner
+ *
+ * This object descriptor implements lttng commands:
+ * LTTNG_UST_ABI_CONTEXT
+ * Prepend a context field to each record of events of this
+ * enabler.
+ * LTTNG_UST_ABI_ENABLE
+ * Enable recording for this enabler
+ * LTTNG_UST_ABI_DISABLE
+ * Disable recording for this enabler
+ * LTTNG_UST_ABI_FILTER
+ * Attach a filter to an enabler.
+ * LTTNG_UST_ABI_EXCLUSION
+ * Attach exclusions to an enabler.
+ */
+static
+long lttng_event_enabler_cmd(int objd, unsigned int cmd, unsigned long arg,
+ union lttng_ust_abi_args *uargs __attribute__((unused)),
+ void *owner __attribute__((unused)))
+{
+ struct lttng_event_enabler *enabler = objd_private(objd);
+
+ switch (cmd) {
+ case LTTNG_UST_ABI_CONTEXT:
+ return lttng_event_enabler_attach_context(enabler,
+ (struct lttng_ust_abi_context *) arg);
+ case LTTNG_UST_ABI_ENABLE:
+ return lttng_event_enabler_enable(enabler);
+ case LTTNG_UST_ABI_DISABLE:
+ return lttng_event_enabler_disable(enabler);
+ case LTTNG_UST_ABI_FILTER:
+ {
+ int ret;
+
+ ret = lttng_event_enabler_attach_filter_bytecode(enabler,
+ (struct lttng_ust_bytecode_node **) arg);
+ if (ret)
+ return ret;
+ return 0;
+ }
+ case LTTNG_UST_ABI_EXCLUSION:
+ {
+ return lttng_event_enabler_attach_exclusion(enabler,
+ (struct lttng_ust_excluder_node **) arg);
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+static
+int lttng_event_enabler_release(int objd)
+{
+ struct lttng_event_enabler *event_enabler = objd_private(objd);
+
+ if (event_enabler)
+ return lttng_ust_abi_objd_unref(event_enabler->chan->priv->parent.objd, 0);
+
+ return 0;
+}
+
+static const struct lttng_ust_abi_objd_ops lttng_event_enabler_ops = {
+ .release = lttng_event_enabler_release,
+ .cmd = lttng_event_enabler_cmd,
+};
+
+void lttng_ust_abi_exit(void)
+{
+ lttng_ust_abi_close_in_progress = 1;
+ ust_lock_nocheck();
+ objd_table_destroy();
+ ust_unlock();
+ lttng_ust_abi_close_in_progress = 0;
+}
projects / lttng-ust.git / blobdiff