#define _GNU_SOURCE
#include <errno.h>
+#include <inttypes.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <urcu/compiler.h>
#include <lttng/ust-error.h>
+#include <signal.h>
#include <common/common.h>
#include <common/sessiond-comm/sessiond-comm.h>
+#include "buffer-registry.h"
#include "fd-limit.h"
#include "health.h"
#include "ust-app.h"
/* Next available channel key. */
static unsigned long next_channel_key;
+static unsigned long next_session_id;
/*
* Return the atomically incremented value of next_channel_key.
}
/*
- * Return the consumer socket from the given consumer output with the right
- * bitness. On error, returns NULL.
- *
- * The caller MUST acquire a rcu read side lock and keep it until the socket
- * object reference is not needed anymore.
+ * Return the atomically incremented value of next_session_id.
*/
-static struct consumer_socket *find_consumer_socket_by_bitness(int bits,
- struct consumer_output *consumer)
+static inline unsigned long get_next_session_id(void)
{
- int consumer_fd;
- struct consumer_socket *socket = NULL;
-
- switch (bits) {
- case 64:
- consumer_fd = uatomic_read(&ust_consumerd64_fd);
- break;
- case 32:
- consumer_fd = uatomic_read(&ust_consumerd32_fd);
- break;
- default:
- assert(0);
- goto end;
- }
-
- socket = consumer_find_socket(consumer_fd, consumer);
+ return uatomic_add_return(&next_session_id, 1);
+}
-end:
- return socket;
+static void copy_channel_attr_to_ustctl(
+ struct ustctl_consumer_channel_attr *attr,
+ struct lttng_ust_channel_attr *uattr)
+{
+ /* Copy event attributes since the layout is different. */
+ attr->subbuf_size = uattr->subbuf_size;
+ attr->num_subbuf = uattr->num_subbuf;
+ attr->overwrite = uattr->overwrite;
+ attr->switch_timer_interval = uattr->switch_timer_interval;
+ attr->read_timer_interval = uattr->read_timer_interval;
+ attr->output = uattr->output;
}
/*
assert(node_ptr == &event->node.node);
}
+/*
+ * Close the notify socket from the given RCU head object. This MUST be called
+ * through a call_rcu().
+ */
+static void close_notify_sock_rcu(struct rcu_head *head)
+{
+ int ret;
+ struct ust_app_notify_sock_obj *obj =
+ caa_container_of(head, struct ust_app_notify_sock_obj, head);
+
+ /* Must have a valid fd here. */
+ assert(obj->fd >= 0);
+
+ ret = close(obj->fd);
+ if (ret) {
+ ERR("close notify sock %d RCU", obj->fd);
+ }
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+
+ free(obj);
+}
+
+/*
+ * Return the session registry according to the buffer type of the given
+ * session.
+ *
+ * A registry per UID object MUST exists before calling this function or else
+ * it assert() if not found. RCU read side lock must be acquired.
+ */
+static struct ust_registry_session *get_session_registry(
+ struct ust_app_session *ua_sess)
+{
+ struct ust_registry_session *registry = NULL;
+
+ assert(ua_sess);
+
+ switch (ua_sess->buffer_type) {
+ case LTTNG_BUFFER_PER_PID:
+ {
+ struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
+ if (!reg_pid) {
+ goto error;
+ }
+ registry = reg_pid->registry->reg.ust;
+ break;
+ }
+ case LTTNG_BUFFER_PER_UID:
+ {
+ struct buffer_reg_uid *reg_uid = buffer_reg_uid_find(
+ ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid);
+ if (!reg_uid) {
+ goto error;
+ }
+ registry = reg_uid->registry->reg.ust;
+ break;
+ }
+ default:
+ assert(0);
+ };
+
+error:
+ return registry;
+}
+
/*
* Delete ust context safely. RCU read lock must be held before calling
* this function.
}
/*
- * Delete ust app stream safely. RCU read lock must be held before calling
- * this function.
+ * Release ust data object of the given stream.
+ *
+ * Return 0 on success or else a negative value.
*/
-static
-void delete_ust_app_stream(int sock, struct ust_app_stream *stream)
+static int release_ust_app_stream(int sock, struct ust_app_stream *stream)
{
- int ret;
+ int ret = 0;
assert(stream);
lttng_fd_put(LTTNG_FD_APPS, 2);
free(stream->obj);
}
+
+ return ret;
+}
+
+/*
+ * Delete ust app stream safely. RCU read lock must be held before calling
+ * this function.
+ */
+static
+void delete_ust_app_stream(int sock, struct ust_app_stream *stream)
+{
+ assert(stream);
+
+ (void) release_ust_app_stream(sock, stream);
free(stream);
}
struct ust_app_event *ua_event;
struct ust_app_ctx *ua_ctx;
struct ust_app_stream *stream, *stmp;
+ struct ust_registry_session *registry;
assert(ua_chan);
}
lttng_ht_destroy(ua_chan->events);
- /* Wipe and free registry. */
- ust_registry_channel_destroy(&ua_chan->session->registry, &ua_chan->registry);
+ /* Wipe and free registry from session registry. */
+ registry = get_session_registry(ua_chan->session);
+ if (registry) {
+ ust_registry_channel_del_free(registry, ua_chan->key);
+ }
if (ua_chan->obj != NULL) {
/* Remove channel from application UST object descriptor. */
ERR("UST app sock %d release channel obj failed with ret %d",
sock, ret);
}
- lttng_fd_put(LTTNG_FD_APPS, 2);
+ lttng_fd_put(LTTNG_FD_APPS, 1);
free(ua_chan->obj);
}
free(ua_chan);
}
+/*
+ * Push metadata to consumer socket. The socket lock MUST be acquired.
+ *
+ * On success, return the len of metadata pushed or else a negative value.
+ */
+ssize_t ust_app_push_metadata(struct ust_registry_session *registry,
+ struct consumer_socket *socket, int send_zero_data)
+{
+ int ret;
+ char *metadata_str = NULL;
+ size_t len, offset;
+ ssize_t ret_val;
+
+ assert(registry);
+ assert(socket);
+ /* Should never be 0 which is the initial state. */
+ assert(registry->metadata_key);
+
+ pthread_mutex_lock(®istry->lock);
+
+ offset = registry->metadata_len_sent;
+ len = registry->metadata_len - registry->metadata_len_sent;
+ if (len == 0) {
+ DBG3("No metadata to push for metadata key %" PRIu64,
+ registry->metadata_key);
+ ret_val = len;
+ if (send_zero_data) {
+ DBG("No metadata to push");
+ goto push_data;
+ }
+ goto end;
+ }
+
+ /* Allocate only what we have to send. */
+ metadata_str = zmalloc(len);
+ if (!metadata_str) {
+ PERROR("zmalloc ust app metadata string");
+ ret_val = -ENOMEM;
+ goto error;
+ }
+ /* Copy what we haven't send out. */
+ memcpy(metadata_str, registry->metadata + offset, len);
+ registry->metadata_len_sent += len;
+
+push_data:
+ pthread_mutex_unlock(®istry->lock);
+ ret = consumer_push_metadata(socket, registry->metadata_key,
+ metadata_str, len, offset);
+ if (ret < 0) {
+ ret_val = ret;
+ goto error_push;
+ }
+
+ free(metadata_str);
+ return len;
+
+end:
+error:
+ pthread_mutex_unlock(®istry->lock);
+error_push:
+ free(metadata_str);
+ return ret_val;
+}
+
+/*
+ * For a given application and session, push metadata to consumer. The session
+ * lock MUST be acquired here before calling this.
+ * Either sock or consumer is required : if sock is NULL, the default
+ * socket to send the metadata is retrieved from consumer, if sock
+ * is not NULL we use it to send the metadata.
+ *
+ * Return 0 on success else a negative error.
+ */
+static int push_metadata(struct ust_registry_session *registry,
+ struct consumer_output *consumer)
+{
+ int ret_val;
+ ssize_t ret;
+ struct consumer_socket *socket;
+
+ assert(registry);
+ assert(consumer);
+
+ rcu_read_lock();
+
+ /*
+ * Means that no metadata was assigned to the session. This can happens if
+ * no start has been done previously.
+ */
+ if (!registry->metadata_key) {
+ ret_val = 0;
+ goto error_rcu_unlock;
+ }
+
+ /* Get consumer socket to use to push the metadata.*/
+ socket = consumer_find_socket_by_bitness(registry->bits_per_long,
+ consumer);
+ if (!socket) {
+ ret_val = -1;
+ goto error_rcu_unlock;
+ }
+
+ /*
+ * TODO: Currently, we hold the socket lock around sampling of the next
+ * metadata segment to ensure we send metadata over the consumer socket in
+ * the correct order. This makes the registry lock nest inside the socket
+ * lock.
+ *
+ * Please note that this is a temporary measure: we should move this lock
+ * back into ust_consumer_push_metadata() when the consumer gets the
+ * ability to reorder the metadata it receives.
+ */
+ pthread_mutex_lock(socket->lock);
+ ret = ust_app_push_metadata(registry, socket, 0);
+ pthread_mutex_unlock(socket->lock);
+ if (ret < 0) {
+ ret_val = ret;
+ goto error_rcu_unlock;
+ }
+
+ rcu_read_unlock();
+ return 0;
+
+error_rcu_unlock:
+ rcu_read_unlock();
+ return ret_val;
+}
+
+/*
+ * Send to the consumer a close metadata command for the given session. Once
+ * done, the metadata channel is deleted and the session metadata pointer is
+ * nullified. The session lock MUST be acquired here unless the application is
+ * in the destroy path.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int close_metadata(struct ust_registry_session *registry,
+ struct consumer_output *consumer)
+{
+ int ret;
+ struct consumer_socket *socket;
+
+ assert(registry);
+ assert(consumer);
+
+ rcu_read_lock();
+
+ if (!registry->metadata_key || registry->metadata_closed) {
+ ret = 0;
+ goto error;
+ }
+
+ /* Get consumer socket to use to push the metadata.*/
+ socket = consumer_find_socket_by_bitness(registry->bits_per_long,
+ consumer);
+ if (!socket) {
+ ret = -1;
+ goto error;
+ }
+
+ ret = consumer_close_metadata(socket, registry->metadata_key);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* Metadata successfully closed. Flag the registry. */
+ registry->metadata_closed = 1;
+
+error:
+ rcu_read_unlock();
+ return ret;
+}
+
/*
* Delete ust app session safely. RCU read lock must be held before calling
* this function.
int ret;
struct lttng_ht_iter iter;
struct ust_app_channel *ua_chan;
+ struct ust_registry_session *registry;
+
+ assert(ua_sess);
+
+ registry = get_session_registry(ua_sess);
+ if (registry) {
+ /* Push metadata for application before freeing the application. */
+ (void) push_metadata(registry, ua_sess->consumer);
- if (ua_sess->metadata) {
- delete_ust_app_channel(sock, ua_sess->metadata, app);
+ /*
+ * Don't ask to close metadata for global per UID buffers. Close
+ * metadata only on destroy trace session in this case.
+ */
+ if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
+ /* And ask to close it for this session registry. */
+ (void) close_metadata(registry, ua_sess->consumer);
+ }
}
cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
}
lttng_ht_destroy(ua_sess->channels);
- ust_registry_session_destroy(&ua_sess->registry);
+ /* In case of per PID, the registry is kept in the session. */
+ if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
+ struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
+ if (reg_pid) {
+ buffer_reg_pid_remove(reg_pid);
+ buffer_reg_pid_destroy(reg_pid);
+ }
+ }
if (ua_sess->handle != -1) {
ret = ustctl_release_handle(sock, ua_sess->handle);
/* Free every object in the session and the session. */
delete_ust_app_session(sock, ua_sess, app);
}
+ lttng_ht_destroy(app->ust_objd);
/*
* Wait until we have deleted the application from the sock hash table
ua_sess->handle = -1;
ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
pthread_mutex_init(&ua_sess->lock, NULL);
- if (ust_registry_session_init(&ua_sess->registry, app,
- app->bits_per_long,
- app->uint8_t_alignment,
- app->uint16_t_alignment,
- app->uint32_t_alignment,
- app->uint64_t_alignment,
- app->long_alignment,
- app->byte_order)) {
- goto error;
- }
return ua_sess;
-error:
- free(ua_sess);
error_free:
return NULL;
}
ua_chan->enabled = 1;
ua_chan->handle = -1;
+ ua_chan->session = ua_sess;
ua_chan->key = get_next_channel_key();
ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
- /* Initialize UST registry. */
- ust_registry_channel_init(&ua_sess->registry, &ua_chan->registry);
-
/* Copy attributes */
if (attr) {
/* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
}
/*
- * Create the specified channel onto the UST tracer for a UST session.
- * Called with UST app session lock held.
+ * Send channel and stream buffer to application.
*
* Return 0 on success. On error, a negative value is returned.
*/
-static int create_ust_channel(struct ust_app *app,
- struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
- struct consumer_output *consumer)
+static int send_channel_pid_to_ust(struct ust_app *app,
+ struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
{
int ret;
- unsigned int nb_fd = 0;
- struct consumer_socket *socket;
struct ust_app_stream *stream, *stmp;
assert(app);
assert(ua_sess);
assert(ua_chan);
- assert(consumer);
-
- health_code_update();
-
- /* Get the right consumer socket for the application. */
- socket = find_consumer_socket_by_bitness(app->bits_per_long, consumer);
- if (!socket) {
- ret = -1;
- goto error;
- }
-
- health_code_update();
-
- /*
- * Ask consumer to create channel. The consumer will return the number of
- * stream we have to expect.
- */
- ret = ust_consumer_ask_channel(ua_sess, ua_chan, consumer, socket);
- if (ret < 0) {
- goto error;
- }
-
- /*
- * Compute the number of fd needed before receiving them. It must be 2 per
- * stream.
- */
- nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
-
- /* Reserve the amount of file descriptor we need. */
- ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
- if (ret < 0) {
- ERR("Exhausted number of available FD upon create channel");
- goto error_fd_get;
- }
health_code_update();
- /*
- * Now get the channel from the consumer. This call wil populate the stream
- * list of that channel and set the ust object.
- */
- ret = ust_consumer_get_channel(socket, ua_chan);
- if (ret < 0) {
- goto error_destroy;
- }
+ DBG("UST app sending channel %s to UST app sock %d", ua_chan->name,
+ app->sock);
/* Send channel to the application. */
ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
goto error;
}
+ health_code_update();
+
/* Send all streams to application. */
cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
cds_list_del(&stream->list);
delete_ust_app_stream(-1, stream);
}
-
/* Flag the channel that it is sent to the application. */
ua_chan->is_sent = 1;
- /* Assign session to channel. */
- ua_chan->session = ua_sess;
- /* Initialize ust objd object using the received handle and add it. */
- lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
- lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
-
- health_code_update();
- /* If channel is not enabled, disable it on the tracer */
- if (!ua_chan->enabled) {
- ret = disable_ust_channel(app, ua_sess, ua_chan);
- if (ret < 0) {
- goto error;
- }
- }
-
- return 0;
-
-error_destroy:
- lttng_fd_put(LTTNG_FD_APPS, nb_fd);
-error_fd_get:
- /*
- * Initiate a destroy channel on the consumer since we had an error
- * handling it on our side. The return value is of no importance since we
- * already have a ret value set by the previous error that we need to
- * return.
- */
- (void) ust_consumer_destroy_channel(socket, ua_chan);
error:
health_code_update();
return ret;
*/
ua_chan->enabled = uchan->enabled;
+ ua_chan->tracing_channel_id = uchan->id;
cds_lfht_for_each_entry(uchan->ctx->ht, &iter.iter, uctx, node.node) {
ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
DBG2("Shadow copy of session handle %d", ua_sess->handle);
- ua_sess->id = usess->id;
- ua_sess->uid = usess->uid;
- ua_sess->gid = usess->gid;
-
- ret = snprintf(ua_sess->path, PATH_MAX, "%s-%d-%s/", app->name, app->pid,
- datetime);
+ ua_sess->tracing_id = usess->id;
+ ua_sess->id = get_next_session_id();
+ ua_sess->uid = app->uid;
+ ua_sess->gid = app->gid;
+ ua_sess->euid = usess->uid;
+ ua_sess->egid = usess->gid;
+ ua_sess->buffer_type = usess->buffer_type;
+ ua_sess->bits_per_long = app->bits_per_long;
+ /* There is only one consumer object per session possible. */
+ ua_sess->consumer = usess->consumer;
+
+ switch (ua_sess->buffer_type) {
+ case LTTNG_BUFFER_PER_PID:
+ ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
+ DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s/", app->name, app->pid,
+ datetime);
+ break;
+ case LTTNG_BUFFER_PER_UID:
+ ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
+ DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long);
+ break;
+ default:
+ assert(0);
+ goto error;
+ }
if (ret < 0) {
PERROR("asprintf UST shadow copy session");
- /* TODO: We cannot return an error from here.. */
assert(0);
+ goto error;
}
- /* TODO: support all UST domain */
-
/* Iterate over all channels in global domain. */
cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
uchan, node.node) {
lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
}
+
+error:
+ return;
}
/*
return NULL;
}
+/*
+ * Setup buffer registry per PID for the given session and application. If none
+ * is found, a new one is created, added to the global registry and
+ * initialized. If regp is valid, it's set with the newly created object.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int setup_buffer_reg_pid(struct ust_app_session *ua_sess,
+ struct ust_app *app, struct buffer_reg_pid **regp)
+{
+ int ret = 0;
+ struct buffer_reg_pid *reg_pid;
+
+ assert(ua_sess);
+ assert(app);
+
+ rcu_read_lock();
+
+ reg_pid = buffer_reg_pid_find(ua_sess->id);
+ if (!reg_pid) {
+ /*
+ * This is the create channel path meaning that if there is NO
+ * registry available, we have to create one for this session.
+ */
+ ret = buffer_reg_pid_create(ua_sess->id, ®_pid);
+ if (ret < 0) {
+ goto error;
+ }
+ buffer_reg_pid_add(reg_pid);
+ } else {
+ goto end;
+ }
+
+ /* Initialize registry. */
+ ret = ust_registry_session_init(®_pid->registry->reg.ust, app,
+ app->bits_per_long, app->uint8_t_alignment,
+ app->uint16_t_alignment, app->uint32_t_alignment,
+ app->uint64_t_alignment, app->long_alignment, app->byte_order);
+ if (ret < 0) {
+ goto error;
+ }
+
+ DBG3("UST app buffer registry per PID created successfully");
+
+end:
+ if (regp) {
+ *regp = reg_pid;
+ }
+error:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Setup buffer registry per UID for the given session and application. If none
+ * is found, a new one is created, added to the global registry and
+ * initialized. If regp is valid, it's set with the newly created object.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int setup_buffer_reg_uid(struct ltt_ust_session *usess,
+ struct ust_app *app, struct buffer_reg_uid **regp)
+{
+ int ret = 0;
+ struct buffer_reg_uid *reg_uid;
+
+ assert(usess);
+ assert(app);
+
+ rcu_read_lock();
+
+ reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
+ if (!reg_uid) {
+ /*
+ * This is the create channel path meaning that if there is NO
+ * registry available, we have to create one for this session.
+ */
+ ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid,
+ LTTNG_DOMAIN_UST, ®_uid);
+ if (ret < 0) {
+ goto error;
+ }
+ buffer_reg_uid_add(reg_uid);
+ } else {
+ goto end;
+ }
+
+ /* Initialize registry. */
+ ret = ust_registry_session_init(®_uid->registry->reg.ust, app,
+ app->bits_per_long, app->uint8_t_alignment,
+ app->uint16_t_alignment, app->uint32_t_alignment,
+ app->uint64_t_alignment, app->long_alignment, app->byte_order);
+ if (ret < 0) {
+ goto error;
+ }
+ /* Add node to teardown list of the session. */
+ cds_list_add(®_uid->lnode, &usess->buffer_reg_uid_list);
+
+ DBG3("UST app buffer registry per UID created successfully");
+
+end:
+ if (regp) {
+ *regp = reg_uid;
+ }
+error:
+ rcu_read_unlock();
+ return ret;
+}
+
/*
* Create a session on the tracer side for the given app.
*
created = 1;
}
+ switch (usess->buffer_type) {
+ case LTTNG_BUFFER_PER_PID:
+ /* Init local registry. */
+ ret = setup_buffer_reg_pid(ua_sess, app, NULL);
+ if (ret < 0) {
+ goto error;
+ }
+ break;
+ case LTTNG_BUFFER_PER_UID:
+ /* Look for a global registry. If none exists, create one. */
+ ret = setup_buffer_reg_uid(usess, app, NULL);
+ if (ret < 0) {
+ goto error;
+ }
+ break;
+ default:
+ assert(0);
+ ret = -EINVAL;
+ goto error;
+ }
+
health_code_update();
if (ua_sess->handle == -1) {
ua_sess->handle = ret;
/* Add ust app session to app's HT */
- lttng_ht_node_init_ulong(&ua_sess->node, (unsigned long) ua_sess->id);
+ lttng_ht_node_init_ulong(&ua_sess->node,
+ (unsigned long) ua_sess->tracing_id);
lttng_ht_add_unique_ulong(app->sessions, &ua_sess->node);
DBG2("UST app session created successfully with handle %d", ret);
if (is_created) {
*is_created = created;
}
+
/* Everything went well. */
ret = 0;
/*
* Create a context for the channel on the tracer.
*
- * Called with UST app session lock held.
+ * Called with UST app session lock held and a RCU read side lock.
*/
static
int create_ust_app_channel_context(struct ust_app_session *ua_sess,
{
int ret;
- ret = disable_ust_event(app, ua_sess, ua_event);
+ ret = disable_ust_event(app, ua_sess, ua_event);
+ if (ret < 0) {
+ goto error;
+ }
+
+ ua_event->enabled = 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Lookup ust app channel for session and disable it on the tracer side.
+ */
+static
+int disable_ust_app_channel(struct ust_app_session *ua_sess,
+ struct ust_app_channel *ua_chan, struct ust_app *app)
+{
+ int ret;
+
+ ret = disable_ust_channel(app, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ ua_chan->enabled = 0;
+
+error:
+ return ret;
+}
+
+/*
+ * Lookup ust app channel for session and enable it on the tracer side. This
+ * MUST be called with a RCU read side lock acquired.
+ */
+static int enable_ust_app_channel(struct ust_app_session *ua_sess,
+ struct ltt_ust_channel *uchan, struct ust_app *app)
+{
+ int ret = 0;
+ struct lttng_ht_iter iter;
+ struct lttng_ht_node_str *ua_chan_node;
+ struct ust_app_channel *ua_chan;
+
+ lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
+ ua_chan_node = lttng_ht_iter_get_node_str(&iter);
+ if (ua_chan_node == NULL) {
+ DBG2("Unable to find channel %s in ust session id %u",
+ uchan->name, ua_sess->tracing_id);
+ goto error;
+ }
+
+ ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
+
+ ret = enable_ust_channel(app, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Ask the consumer to create a channel and get it if successful.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int do_consumer_create_channel(struct ltt_ust_session *usess,
+ struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
+ int bitness, struct ust_registry_session *registry)
+{
+ int ret;
+ unsigned int nb_fd = 0;
+ struct consumer_socket *socket;
+
+ assert(usess);
+ assert(ua_sess);
+ assert(ua_chan);
+ assert(registry);
+
+ rcu_read_lock();
+ health_code_update();
+
+ /* Get the right consumer socket for the application. */
+ socket = consumer_find_socket_by_bitness(bitness, usess->consumer);
+ if (!socket) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ health_code_update();
+
+ /* Need one fd for the channel. */
+ ret = lttng_fd_get(LTTNG_FD_APPS, 1);
+ if (ret < 0) {
+ ERR("Exhausted number of available FD upon create channel");
+ goto error;
+ }
+
+ /*
+ * Ask consumer to create channel. The consumer will return the number of
+ * stream we have to expect.
+ */
+ ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket,
+ registry);
+ if (ret < 0) {
+ goto error_ask;
+ }
+
+ /*
+ * Compute the number of fd needed before receiving them. It must be 2 per
+ * stream (2 being the default value here).
+ */
+ nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
+
+ /* Reserve the amount of file descriptor we need. */
+ ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
+ if (ret < 0) {
+ ERR("Exhausted number of available FD upon create channel");
+ goto error_fd_get_stream;
+ }
+
+ health_code_update();
+
+ /*
+ * Now get the channel from the consumer. This call wil populate the stream
+ * list of that channel and set the ust objects.
+ */
+ ret = ust_consumer_get_channel(socket, ua_chan);
+ if (ret < 0) {
+ goto error_destroy;
+ }
+
+ rcu_read_unlock();
+ return 0;
+
+error_destroy:
+ lttng_fd_put(LTTNG_FD_APPS, nb_fd);
+error_fd_get_stream:
+ /*
+ * Initiate a destroy channel on the consumer since we had an error
+ * handling it on our side. The return value is of no importance since we
+ * already have a ret value set by the previous error that we need to
+ * return.
+ */
+ (void) ust_consumer_destroy_channel(socket, ua_chan);
+error_ask:
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+error:
+ health_code_update();
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Duplicate the ust data object of the ust app stream and save it in the
+ * buffer registry stream.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int duplicate_stream_object(struct buffer_reg_stream *reg_stream,
+ struct ust_app_stream *stream)
+{
+ int ret;
+
+ assert(reg_stream);
+ assert(stream);
+
+ /* Reserve the amount of file descriptor we need. */
+ ret = lttng_fd_get(LTTNG_FD_APPS, 2);
+ if (ret < 0) {
+ ERR("Exhausted number of available FD upon duplicate stream");
+ goto error;
+ }
+
+ /* Duplicate object for stream once the original is in the registry. */
+ ret = ustctl_duplicate_ust_object_data(&stream->obj,
+ reg_stream->obj.ust);
+ if (ret < 0) {
+ ERR("Duplicate stream obj from %p to %p failed with ret %d",
+ reg_stream->obj.ust, stream->obj, ret);
+ lttng_fd_put(LTTNG_FD_APPS, 2);
+ goto error;
+ }
+ stream->handle = stream->obj->handle;
+
+error:
+ return ret;
+}
+
+/*
+ * Duplicate the ust data object of the ust app. channel and save it in the
+ * buffer registry channel.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int duplicate_channel_object(struct buffer_reg_channel *reg_chan,
+ struct ust_app_channel *ua_chan)
+{
+ int ret;
+
+ assert(reg_chan);
+ assert(ua_chan);
+
+ /* Need two fds for the channel. */
+ ret = lttng_fd_get(LTTNG_FD_APPS, 1);
+ if (ret < 0) {
+ ERR("Exhausted number of available FD upon duplicate channel");
+ goto error_fd_get;
+ }
+
+ /* Duplicate object for stream once the original is in the registry. */
+ ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust);
+ if (ret < 0) {
+ ERR("Duplicate channel obj from %p to %p failed with ret: %d",
+ reg_chan->obj.ust, ua_chan->obj, ret);
+ goto error;
+ }
+ ua_chan->handle = ua_chan->obj->handle;
+
+ return 0;
+
+error:
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+error_fd_get:
+ return ret;
+}
+
+/*
+ * For a given channel buffer registry, setup all streams of the given ust
+ * application channel.
+ *
+ * Return 0 on success or else a negative value.
+ */
+static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan,
+ struct ust_app_channel *ua_chan)
+{
+ int ret = 0;
+ struct ust_app_stream *stream, *stmp;
+
+ assert(reg_chan);
+ assert(ua_chan);
+
+ DBG2("UST app setup buffer registry stream");
+
+ /* Send all streams to application. */
+ cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
+ struct buffer_reg_stream *reg_stream;
+
+ ret = buffer_reg_stream_create(®_stream);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /*
+ * Keep original pointer and nullify it in the stream so the delete
+ * stream call does not release the object.
+ */
+ reg_stream->obj.ust = stream->obj;
+ stream->obj = NULL;
+ buffer_reg_stream_add(reg_stream, reg_chan);
+
+ /* We don't need the streams anymore. */
+ cds_list_del(&stream->list);
+ delete_ust_app_stream(-1, stream);
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Create a buffer registry channel for the given session registry and
+ * application channel object. If regp pointer is valid, it's set with the
+ * created object. Important, the created object is NOT added to the session
+ * registry hash table.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess,
+ struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp)
+{
+ int ret;
+ struct buffer_reg_channel *reg_chan = NULL;
+
+ assert(reg_sess);
+ assert(ua_chan);
+
+ DBG2("UST app creating buffer registry channel for %s", ua_chan->name);
+
+ /* Create buffer registry channel. */
+ ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, ®_chan);
+ if (ret < 0) {
+ goto error_create;
+ }
+ assert(reg_chan);
+ reg_chan->consumer_key = ua_chan->key;
+
+ /* Create and add a channel registry to session. */
+ ret = ust_registry_channel_add(reg_sess->reg.ust,
+ ua_chan->tracing_channel_id);
+ if (ret < 0) {
+ goto error;
+ }
+ buffer_reg_channel_add(reg_sess, reg_chan);
+
+ if (regp) {
+ *regp = reg_chan;
+ }
+
+ return 0;
+
+error:
+ /* Safe because the registry channel object was not added to any HT. */
+ buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
+error_create:
+ return ret;
+}
+
+/*
+ * Setup buffer registry channel for the given session registry and application
+ * channel object. If regp pointer is valid, it's set with the created object.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess,
+ struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan)
+{
+ int ret;
+
+ assert(reg_sess);
+ assert(reg_chan);
+ assert(ua_chan);
+ assert(ua_chan->obj);
+
+ DBG2("UST app setup buffer registry channel for %s", ua_chan->name);
+
+ /* Setup all streams for the registry. */
+ ret = setup_buffer_reg_streams(reg_chan, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ reg_chan->obj.ust = ua_chan->obj;
+ ua_chan->obj = NULL;
+
+ return 0;
+
+error:
+ buffer_reg_channel_remove(reg_sess, reg_chan);
+ buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
+ return ret;
+}
+
+/*
+ * Send buffer registry channel to the application.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan,
+ struct ust_app *app, struct ust_app_session *ua_sess,
+ struct ust_app_channel *ua_chan)
+{
+ int ret;
+ struct buffer_reg_stream *reg_stream;
+
+ assert(reg_chan);
+ assert(app);
+ assert(ua_sess);
+ assert(ua_chan);
+
+ DBG("UST app sending buffer registry channel to ust sock %d", app->sock);
+
+ ret = duplicate_channel_object(reg_chan, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* Send channel to the application. */
+ ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ health_code_update();
+
+ /* Send all streams to application. */
+ pthread_mutex_lock(®_chan->stream_list_lock);
+ cds_list_for_each_entry(reg_stream, ®_chan->streams, lnode) {
+ struct ust_app_stream stream;
+
+ ret = duplicate_stream_object(reg_stream, &stream);
+ if (ret < 0) {
+ goto error_stream_unlock;
+ }
+
+ ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream);
+ if (ret < 0) {
+ goto error_stream_unlock;
+ }
+
+ /*
+ * The return value is not important here. This function will output an
+ * error if needed.
+ */
+ (void) release_ust_app_stream(-1, &stream);
+ }
+ ua_chan->is_sent = 1;
+
+error_stream_unlock:
+ pthread_mutex_unlock(®_chan->stream_list_lock);
+error:
+ return ret;
+}
+
+/*
+ * Create and send to the application the created buffers with per UID buffers.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int create_channel_per_uid(struct ust_app *app,
+ struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
+ struct ust_app_channel *ua_chan)
+{
+ int ret;
+ struct buffer_reg_uid *reg_uid;
+ struct buffer_reg_channel *reg_chan;
+
+ assert(app);
+ assert(usess);
+ assert(ua_sess);
+ assert(ua_chan);
+
+ DBG("UST app creating channel %s with per UID buffers", ua_chan->name);
+
+ reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
+ /*
+ * The session creation handles the creation of this global registry
+ * object. If none can be find, there is a code flow problem or a
+ * teardown race.
+ */
+ assert(reg_uid);
+
+ reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id,
+ reg_uid);
+ if (!reg_chan) {
+ /* Create the buffer registry channel object. */
+ ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, ®_chan);
+ if (ret < 0) {
+ goto error;
+ }
+ assert(reg_chan);
+
+ /*
+ * Create the buffers on the consumer side. This call populates the
+ * ust app channel object with all streams and data object.
+ */
+ ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
+ app->bits_per_long, reg_uid->registry->reg.ust);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /*
+ * Setup the streams and add it to the session registry.
+ */
+ ret = setup_buffer_reg_channel(reg_uid->registry, ua_chan, reg_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+ }
+
+ /* Send buffers to the application. */
+ ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Create and send to the application the created buffers with per PID buffers.
+ *
+ * Return 0 on success else a negative value.
+ */
+static int create_channel_per_pid(struct ust_app *app,
+ struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
+ struct ust_app_channel *ua_chan)
+{
+ int ret;
+ struct ust_registry_session *registry;
+
+ assert(app);
+ assert(usess);
+ assert(ua_sess);
+ assert(ua_chan);
+
+ DBG("UST app creating channel %s with per PID buffers", ua_chan->name);
+
+ rcu_read_lock();
+
+ registry = get_session_registry(ua_sess);
+ assert(registry);
+
+ /* Create and add a new channel registry to session. */
+ ret = ust_registry_channel_add(registry, ua_chan->key);
+ if (ret < 0) {
+ goto error;
+ }
+
+ /* Create and get channel on the consumer side. */
+ ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
+ app->bits_per_long, registry);
if (ret < 0) {
goto error;
}
- ua_event->enabled = 0;
-
-error:
- return ret;
-}
-
-/*
- * Lookup ust app channel for session and disable it on the tracer side.
- */
-static
-int disable_ust_app_channel(struct ust_app_session *ua_sess,
- struct ust_app_channel *ua_chan, struct ust_app *app)
-{
- int ret;
-
- ret = disable_ust_channel(app, ua_sess, ua_chan);
+ ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
if (ret < 0) {
goto error;
}
- ua_chan->enabled = 0;
-
error:
+ rcu_read_unlock();
return ret;
}
/*
- * Lookup ust app channel for session and enable it on the tracer side.
+ * From an already allocated ust app channel, create the channel buffers if
+ * need and send it to the application. This MUST be called with a RCU read
+ * side lock acquired.
+ *
+ * Return 0 on success or else a negative value.
*/
-static int enable_ust_app_channel(struct ust_app_session *ua_sess,
- struct ltt_ust_channel *uchan, struct ust_app *app)
+static int do_create_channel(struct ust_app *app,
+ struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
+ struct ust_app_channel *ua_chan)
{
- int ret = 0;
- struct lttng_ht_iter iter;
- struct lttng_ht_node_str *ua_chan_node;
- struct ust_app_channel *ua_chan;
+ int ret;
- lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
- ua_chan_node = lttng_ht_iter_get_node_str(&iter);
- if (ua_chan_node == NULL) {
- DBG2("Unable to find channel %s in ust session id %u",
- uchan->name, ua_sess->id);
+ assert(app);
+ assert(usess);
+ assert(ua_sess);
+ assert(ua_chan);
+
+ /* Handle buffer type before sending the channel to the application. */
+ switch (usess->buffer_type) {
+ case LTTNG_BUFFER_PER_UID:
+ {
+ ret = create_channel_per_uid(app, usess, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+ break;
+ }
+ case LTTNG_BUFFER_PER_PID:
+ {
+ ret = create_channel_per_pid(app, usess, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
+ break;
+ }
+ default:
+ assert(0);
+ ret = -EINVAL;
goto error;
}
- ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
+ /* Initialize ust objd object using the received handle and add it. */
+ lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
+ lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
- ret = enable_ust_channel(app, ua_sess, ua_chan);
- if (ret < 0) {
- goto error;
+ /* If channel is not enabled, disable it on the tracer */
+ if (!ua_chan->enabled) {
+ ret = disable_ust_channel(app, ua_sess, ua_chan);
+ if (ret < 0) {
+ goto error;
+ }
}
error:
* newly created channel if not NULL.
*
* Called with UST app session lock held.
+ *
+ * Return 0 on success or else a negative value.
*/
static int create_ust_app_channel(struct ust_app_session *ua_sess,
struct ltt_ust_channel *uchan, struct ust_app *app,
- struct consumer_output *consumer, enum lttng_ust_chan_type type,
+ enum lttng_ust_chan_type type, struct ltt_ust_session *usess,
struct ust_app_channel **ua_chanp)
{
int ret = 0;
/* Set channel type. */
ua_chan->attr.type = type;
- ret = create_ust_channel(app, ua_sess, ua_chan, consumer);
+ ret = do_create_channel(app, usess, ua_sess, ua_chan);
if (ret < 0) {
goto error;
}
/*
* Create UST metadata and open it on the tracer side.
*
- * Called with UST app session lock held.
+ * Called with UST app session lock held and RCU read side lock.
*/
static int create_ust_app_metadata(struct ust_app_session *ua_sess,
- struct ust_app *app, struct consumer_output *consumer)
+ struct ust_app *app, struct consumer_output *consumer,
+ struct ustctl_consumer_channel_attr *attr)
{
int ret = 0;
struct ust_app_channel *metadata;
+ struct consumer_socket *socket;
+ struct ust_registry_session *registry;
assert(ua_sess);
assert(app);
+ assert(consumer);
- if (ua_sess->metadata) {
- /* Already exist. Return success. */
- goto end;
+ registry = get_session_registry(ua_sess);
+ assert(registry);
+
+ /* Metadata already exists for this registry. */
+ if (registry->metadata_key) {
+ ret = 0;
+ goto error;
}
/* Allocate UST metadata */
goto error;
}
- /* Set default attributes for metadata. */
- metadata->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
- metadata->attr.subbuf_size = default_get_metadata_subbuf_size();
- metadata->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
- metadata->attr.switch_timer_interval = DEFAULT_CHANNEL_SWITCH_TIMER;
- metadata->attr.read_timer_interval = DEFAULT_CHANNEL_READ_TIMER;
- metadata->attr.output = LTTNG_UST_MMAP;
- metadata->attr.type = LTTNG_UST_CHAN_METADATA;
+ if (!attr) {
+ /* Set default attributes for metadata. */
+ metadata->attr.overwrite = DEFAULT_CHANNEL_OVERWRITE;
+ metadata->attr.subbuf_size = default_get_metadata_subbuf_size();
+ metadata->attr.num_subbuf = DEFAULT_METADATA_SUBBUF_NUM;
+ metadata->attr.switch_timer_interval = DEFAULT_UST_CHANNEL_SWITCH_TIMER;
+ metadata->attr.read_timer_interval = DEFAULT_UST_CHANNEL_READ_TIMER;
+ metadata->attr.output = LTTNG_UST_MMAP;
+ metadata->attr.type = LTTNG_UST_CHAN_METADATA;
+ } else {
+ memcpy(&metadata->attr, attr, sizeof(metadata->attr));
+ metadata->attr.output = LTTNG_UST_MMAP;
+ metadata->attr.type = LTTNG_UST_CHAN_METADATA;
+ }
+
+ /* Get the right consumer socket for the application. */
+ socket = consumer_find_socket_by_bitness(app->bits_per_long, consumer);
+ if (!socket) {
+ ret = -EINVAL;
+ goto error_consumer;
+ }
- ret = create_ust_channel(app, ua_sess, metadata, consumer);
+ /* Need one fd for the channel. */
+ ret = lttng_fd_get(LTTNG_FD_APPS, 1);
if (ret < 0) {
- goto error_create;
+ ERR("Exhausted number of available FD upon create metadata");
+ goto error;
}
- ua_sess->metadata = metadata;
+ /*
+ * Keep metadata key so we can identify it on the consumer side. Assign it
+ * to the registry *before* we ask the consumer so we avoid the race of the
+ * consumer requesting the metadata and the ask_channel call on our side
+ * did not returned yet.
+ */
+ registry->metadata_key = metadata->key;
- DBG2("UST metadata opened for app pid %d", app->pid);
+ /*
+ * Ask the metadata channel creation to the consumer. The metadata object
+ * will be created by the consumer and kept their. However, the stream is
+ * never added or monitored until we do a first push metadata to the
+ * consumer.
+ */
+ ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket,
+ registry);
+ if (ret < 0) {
+ /*
+ * Safe because the metadata obj pointer is not set so the delete below
+ * will not put a FD back again.
+ */
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+ goto error_consumer;
+ }
-end:
- return 0;
-error_create:
- delete_ust_app_channel(metadata->is_sent ? app->sock : -1, metadata, app);
+ /*
+ * The setup command will make the metadata stream be sent to the relayd,
+ * if applicable, and the thread managing the metadatas. This is important
+ * because after this point, if an error occurs, the only way the stream
+ * can be deleted is to be monitored in the consumer.
+ */
+ ret = consumer_setup_metadata(socket, metadata->key);
+ if (ret < 0) {
+ /*
+ * Safe because the metadata obj pointer is not set so the delete below
+ * will not put a FD back again.
+ */
+ lttng_fd_put(LTTNG_FD_APPS, 1);
+ goto error_consumer;
+ }
+
+ DBG2("UST metadata with key %" PRIu64 " created for app pid %d",
+ metadata->key, app->pid);
+
+error_consumer:
+ delete_ust_app_channel(-1, metadata, app);
error:
return ret;
}
}
/*
- * Return ust app pointer or NULL if not found.
+ * Return ust app pointer or NULL if not found. RCU read side lock MUST be
+ * acquired before calling this function.
*/
struct ust_app *ust_app_find_by_pid(pid_t pid)
{
+ struct ust_app *app = NULL;
struct lttng_ht_node_ulong *node;
struct lttng_ht_iter iter;
DBG2("Found UST app by pid %d", pid);
- return caa_container_of(node, struct ust_app, pid_n);
+ app = caa_container_of(node, struct ust_app, pid_n);
error:
- rcu_read_unlock();
- return NULL;
+ return app;
}
+/*
+ * Allocate and init an UST app object using the registration information and
+ * the command socket. This is called when the command socket connects to the
+ * session daemon.
+ *
+ * The object is returned on success or else NULL.
+ */
struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
{
struct ust_app *lta = NULL;
lta->ppid = msg->ppid;
lta->uid = msg->uid;
lta->gid = msg->gid;
- lta->compatible = 0; /* Not compatible until proven */
lta->bits_per_long = msg->bits_per_long;
lta->uint8_t_alignment = msg->uint8_t_alignment;
lta->v_major = msg->major;
lta->v_minor = msg->minor;
- strncpy(lta->name, msg->name, sizeof(lta->name));
- lta->name[LTTNG_UST_ABI_PROCNAME_LEN] = '\0';
lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
lta->notify_sock = -1;
+
+ /* Copy name and make sure it's NULL terminated. */
+ strncpy(lta->name, msg->name, sizeof(lta->name));
+ lta->name[UST_APP_PROCNAME_LEN] = '\0';
+
+ /*
+ * Before this can be called, when receiving the registration information,
+ * the application compatibility is checked. So, at this point, the
+ * application can work with this session daemon.
+ */
lta->compatible = 1;
lta->pid = msg->pid;
return lta;
}
+/*
+ * For a given application object, add it to every hash table.
+ */
void ust_app_add(struct ust_app *app)
{
assert(app);
lttng_ht_add_unique_ulong(ust_app_ht_by_notify_sock, &app->notify_sock_n);
DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s "
- "(version %d.%d)", app->pid, app->ppid, app->uid, app->gid,
- app->sock, app->name, app->v_major, app->v_minor);
+ "notify_sock:%d (version %d.%d)", app->pid, app->ppid, app->uid,
+ app->gid, app->sock, app->name, app->notify_sock, app->v_major,
+ app->v_minor);
rcu_read_unlock();
}
+/*
+ * Set the application version into the object.
+ *
+ * Return 0 on success else a negative value either an errno code or a
+ * LTTng-UST error code.
+ */
int ust_app_version(struct ust_app *app)
{
+ int ret;
+
assert(app);
- return ustctl_tracer_version(app->sock, &app->version);
+
+ ret = ustctl_tracer_version(app->sock, &app->version);
+ if (ret < 0) {
+ if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
+ ERR("UST app %d verson failed with ret %d", app->sock, ret);
+ } else {
+ DBG3("UST app %d verion failed. Application is dead", app->sock);
+ }
+ }
+
+ return ret;
}
/*
ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
assert(!ret);
- /* Remove application from notify hash table */
+ /*
+ * Remove application from notify hash table. The thread handling the
+ * notify socket could have deleted the node so ignore on error because
+ * either way it's valid. The close of that socket is handled by the other
+ * thread.
+ */
iter.iter.node = <a->notify_sock_n.node;
- ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
+ (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
/*
* Ignore return value since the node might have been removed before by an
/* Remove sessions so they are not visible during deletion.*/
cds_lfht_for_each_entry(lta->sessions->ht, &iter.iter, ua_sess,
node.node) {
+ struct ust_registry_session *registry;
+
ret = lttng_ht_del(lta->sessions, &iter);
if (ret) {
/* The session was already removed so scheduled for teardown. */
* Add session to list for teardown. This is safe since at this point we
* are the only one using this list.
*/
+ pthread_mutex_lock(&ua_sess->lock);
+
+ /*
+ * Normally, this is done in the delete session process which is
+ * executed in the call rcu below. However, upon registration we can't
+ * afford to wait for the grace period before pushing data or else the
+ * data pending feature can race between the unregistration and stop
+ * command where the data pending command is sent *before* the grace
+ * period ended.
+ *
+ * The close metadata below nullifies the metadata pointer in the
+ * session so the delete session will NOT push/close a second time.
+ */
+ registry = get_session_registry(ua_sess);
+ if (registry) {
+ /* Push metadata for application before freeing the application. */
+ (void) push_metadata(registry, ua_sess->consumer);
+
+ /*
+ * Don't ask to close metadata for global per UID buffers. Close
+ * metadata only on destroy trace session in this case.
+ */
+ if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
+ /* And ask to close it for this session registry. */
+ (void) close_metadata(registry, ua_sess->consumer);
+ }
+ }
+
cds_list_add(&ua_sess->teardown_node, <a->teardown_head);
+ pthread_mutex_unlock(&ua_sess->lock);
}
/* Free memory */
assert(!ret);
}
+ /* Cleanup notify socket hash table */
+ cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
+ notify_sock_n.node) {
+ ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
+ assert(!ret);
+ }
+
/* Destroy is done only when the ht is empty */
lttng_ht_destroy(ust_app_ht);
lttng_ht_destroy(ust_app_ht_by_sock);
+ lttng_ht_destroy(ust_app_ht_by_notify_sock);
rcu_read_unlock();
}
assert(usess);
assert(uchan);
- DBG2("UST app adding channel %s to global domain for session id %d",
+ DBG2("UST app adding channel %s to UST domain for session id %d",
uchan->name, usess->id);
rcu_read_lock();
assert(ua_sess);
pthread_mutex_lock(&ua_sess->lock);
- /* Create channel onto application. We don't need the chan ref. */
- ret = create_ust_app_channel(ua_sess, uchan, app, usess->consumer,
- LTTNG_UST_CHAN_PER_CPU, NULL);
+ if (!strncmp(uchan->name, DEFAULT_METADATA_NAME,
+ sizeof(uchan->name))) {
+ struct ustctl_consumer_channel_attr attr;
+ copy_channel_attr_to_ustctl(&attr, &uchan->attr);
+ ret = create_ust_app_metadata(ua_sess, app, usess->consumer,
+ &attr);
+ } else {
+ /* Create channel onto application. We don't need the chan ref. */
+ ret = create_ust_app_channel(ua_sess, uchan, app,
+ LTTNG_UST_CHAN_PER_CPU, usess, NULL);
+ }
pthread_mutex_unlock(&ua_sess->lock);
if (ret < 0) {
if (ret == -ENOMEM) {
if (usess->consumer->type == CONSUMER_DST_LOCAL &&
strlen(usess->consumer->dst.trace_path) > 0) {
ret = run_as_mkdir_recursive(usess->consumer->dst.trace_path,
- S_IRWXU | S_IRWXG, usess->uid, usess->gid);
+ S_IRWXU | S_IRWXG, ua_sess->euid, ua_sess->egid);
if (ret < 0) {
if (ret != -EEXIST) {
ERR("Trace directory creation error");
}
}
- /* Create the metadata for the application. */
- ret = create_ust_app_metadata(ua_sess, app, usess->consumer);
+ /*
+ * Create the metadata for the application. This returns gracefully if a
+ * metadata was already set for the session.
+ */
+ ret = create_ust_app_metadata(ua_sess, app, usess->consumer, NULL);
if (ret < 0) {
goto error_unlock;
}
struct lttng_ht_iter iter;
struct ust_app_session *ua_sess;
struct ust_app_channel *ua_chan;
+ struct ust_registry_session *registry;
DBG("Stopping tracing for ust app pid %d", app->pid);
rcu_read_lock();
if (!app->compatible) {
- goto end;
+ goto end_no_session;
}
ua_sess = lookup_session_by_app(usess, app);
if (ua_sess == NULL) {
- goto end;
+ goto end_no_session;
}
+ pthread_mutex_lock(&ua_sess->lock);
+
/*
* If started = 0, it means that stop trace has been called for a session
* that was never started. It's possible since we can have a fail start
DBG3("UST app failed to flush %s. Application is dead.",
ua_chan->name);
/* No need to continue. */
- goto end;
+ break;
}
/* Continuing flushing all buffers */
continue;
health_code_update();
- assert(ua_sess->metadata->is_sent);
- /* Flush all buffers before stopping */
- ret = ustctl_sock_flush_buffer(app->sock, ua_sess->metadata->obj);
- if (ret < 0) {
- if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
- ERR("UST app PID %d metadata flush failed with ret %d", app->pid,
- ret);
- goto error_rcu_unlock;
- } else {
- DBG3("UST app failed to flush metadata. Application is dead.");
- }
- }
+ registry = get_session_registry(ua_sess);
+ assert(registry);
+ /* Push metadata for application before freeing the application. */
+ (void) push_metadata(registry, ua_sess->consumer);
-end:
+ pthread_mutex_unlock(&ua_sess->lock);
+end_no_session:
rcu_read_unlock();
health_code_update();
return 0;
error_rcu_unlock:
+ pthread_mutex_unlock(&ua_sess->lock);
rcu_read_unlock();
health_code_update();
return -1;
ERR("UST app wait quiescent failed for app pid %d ret %d",
app->pid, ret);
}
-
end:
rcu_read_unlock();
health_code_update();
rcu_read_lock();
+ /* Flush all per UID buffers associated to that session. */
+ if (usess->buffer_type == LTTNG_BUFFER_PER_UID) {
+ struct buffer_reg_uid *reg;
+ cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
+ struct buffer_reg_channel *reg_chan;
+ struct consumer_socket *socket;
+
+ /* Get consumer socket to use to push the metadata.*/
+ socket = consumer_find_socket_by_bitness(reg->bits_per_long,
+ usess->consumer);
+ if (!socket) {
+ /* Ignore request if no consumer is found for the session. */
+ continue;
+ }
+
+ cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
+ reg_chan, node.node) {
+ /*
+ * The following call will print error values so the return
+ * code is of little importance because whatever happens, we
+ * have to try them all.
+ */
+ (void) consumer_flush_channel(socket, reg_chan->consumer_key);
+ }
+ }
+ }
+
cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
ret = ust_app_stop_trace(usess, app);
if (ret < 0) {
app = find_app_by_sock(sock);
if (app == NULL) {
- ERR("Failed to find app sock %d", sock);
+ /*
+ * Application can be unregistered before so this is possible hence
+ * simply stopping the update.
+ */
+ DBG3("UST app update failed to find app sock %d", sock);
goto error;
}
*/
cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
node.node) {
- ret = create_ust_channel(app, ua_sess, ua_chan, usess->consumer);
- if (ret < 0) {
- /*
- * Stop everything. On error, the application failed, no more file
- * descriptor are available or ENOMEM so stopping here is the only
- * thing we can do for now.
- */
- goto error_unlock;
+ /*
+ * For a metadata channel, handle it differently.
+ */
+ if (!strncmp(ua_chan->name, DEFAULT_METADATA_NAME,
+ sizeof(ua_chan->name))) {
+ ret = create_ust_app_metadata(ua_sess, app, usess->consumer,
+ &ua_chan->attr);
+ if (ret < 0) {
+ goto error_unlock;
+ }
+ /* Remove it from the hash table and continue!. */
+ ret = lttng_ht_del(ua_sess->channels, &iter);
+ assert(!ret);
+ delete_ust_app_channel(-1, ua_chan, app);
+ continue;
+ } else {
+ ret = do_create_channel(app, usess, ua_sess, ua_chan);
+ if (ret < 0) {
+ /*
+ * Stop everything. On error, the application failed, no more
+ * file descriptor are available or ENOMEM so stopping here is
+ * the only thing we can do for now.
+ */
+ goto error_unlock;
+ }
}
cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter_ctx.iter, ua_ctx,
return ret;
}
+/*
+ * Return a ust app channel object using the application object and the channel
+ * object descriptor has a key. If not found, NULL is returned. A RCU read side
+ * lock MUST be acquired before calling this function.
+ */
static struct ust_app_channel *find_channel_by_objd(struct ust_app *app,
int objd)
{
return ua_chan;
}
+/*
+ * Reply to a register channel notification from an application on the notify
+ * socket. The channel metadata is also created.
+ *
+ * The session UST registry lock is acquired in this function.
+ *
+ * On success 0 is returned else a negative value.
+ */
static int reply_ust_register_channel(int sock, int sobjd, int cobjd,
size_t nr_fields, struct ustctl_field *fields)
{
int ret, ret_code = 0;
uint32_t chan_id, reg_count;
+ uint64_t chan_reg_key;
enum ustctl_channel_header type;
struct ust_app *app;
struct ust_app_channel *ua_chan;
struct ust_app_session *ua_sess;
+ struct ust_registry_session *registry;
+ struct ust_registry_channel *chan_reg;
rcu_read_lock();
/* Lookup application. If not found, there is a code flow error. */
app = find_app_by_notify_sock(sock);
- assert(app);
+ if (!app) {
+ DBG("Application socket %d is being teardown. Abort event notify",
+ sock);
+ ret = 0;
+ goto error_rcu_unlock;
+ }
/* Lookup channel by UST object descriptor. Should always be found. */
ua_chan = find_channel_by_objd(app, cobjd);
assert(ua_chan);
assert(ua_chan->session);
ua_sess = ua_chan->session;
- assert(ua_sess);
- pthread_mutex_lock(&ua_sess->registry.lock);
+ /* Get right session registry depending on the session buffer type. */
+ registry = get_session_registry(ua_sess);
+ assert(registry);
- if (ust_registry_is_max_id(ua_chan->session->registry.used_channel_id)) {
- ret_code = -1;
- chan_id = -1U;
- type = -1;
- goto reply;
- }
-
- /* Don't assign ID to metadata. */
- if (ua_chan->attr.type == LTTNG_UST_CHAN_METADATA) {
- chan_id = -1U;
+ /* Depending on the buffer type, a different channel key is used. */
+ if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
+ chan_reg_key = ua_chan->tracing_channel_id;
} else {
- chan_id = ust_registry_get_next_chan_id(&ua_chan->session->registry);
+ chan_reg_key = ua_chan->key;
}
- reg_count = ust_registry_get_event_count(&ua_chan->registry);
- if (reg_count < 31) {
- type = USTCTL_CHANNEL_HEADER_COMPACT;
+ pthread_mutex_lock(®istry->lock);
+
+ chan_reg = ust_registry_channel_find(registry, chan_reg_key);
+ assert(chan_reg);
+
+ if (!chan_reg->register_done) {
+ reg_count = ust_registry_get_event_count(chan_reg);
+ if (reg_count < 31) {
+ type = USTCTL_CHANNEL_HEADER_COMPACT;
+ } else {
+ type = USTCTL_CHANNEL_HEADER_LARGE;
+ }
+
+ chan_reg->nr_ctx_fields = nr_fields;
+ chan_reg->ctx_fields = fields;
+ chan_reg->header_type = type;
} else {
- type = USTCTL_CHANNEL_HEADER_LARGE;
+ /* Get current already assigned values. */
+ type = chan_reg->header_type;
}
-
- ua_chan->registry.nr_ctx_fields = nr_fields;
- ua_chan->registry.ctx_fields = fields;
- ua_chan->registry.chan_id = chan_id;
- ua_chan->registry.header_type = type;
+ /* Channel id is set during the object creation. */
+ chan_id = chan_reg->chan_id;
/* Append to metadata */
- if (!ret_code) {
- ret_code = ust_metadata_channel_statedump(&ua_chan->session->registry,
- &ua_chan->registry);
+ if (!chan_reg->metadata_dumped) {
+ ret_code = ust_metadata_channel_statedump(registry, chan_reg);
if (ret_code) {
ERR("Error appending channel metadata (errno = %d)", ret_code);
goto reply;
}
reply:
- DBG3("UST app replying to register channel with id %u, type: %d, ret: %d",
- chan_id, type, ret_code);
+ DBG3("UST app replying to register channel key %" PRIu64
+ " with id %u, type: %d, ret: %d", chan_reg_key, chan_id, type,
+ ret_code);
ret = ustctl_reply_register_channel(sock, chan_id, type, ret_code);
if (ret < 0) {
goto error;
}
+ /* This channel registry registration is completed. */
+ chan_reg->register_done = 1;
+
error:
- pthread_mutex_unlock(&ua_sess->registry.lock);
+ pthread_mutex_unlock(®istry->lock);
+error_rcu_unlock:
rcu_read_unlock();
return ret;
}
+/*
+ * Add event to the UST channel registry. When the event is added to the
+ * registry, the metadata is also created. Once done, this replies to the
+ * application with the appropriate error code.
+ *
+ * The session UST registry lock is acquired in the function.
+ *
+ * On success 0 is returned else a negative value.
+ */
static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name,
char *sig, size_t nr_fields, struct ustctl_field *fields, int loglevel,
char *model_emf_uri)
{
int ret, ret_code;
uint32_t event_id = 0;
+ uint64_t chan_reg_key;
struct ust_app *app;
struct ust_app_channel *ua_chan;
struct ust_app_session *ua_sess;
+ struct ust_registry_session *registry;
rcu_read_lock();
/* Lookup application. If not found, there is a code flow error. */
app = find_app_by_notify_sock(sock);
- assert(app);
+ if (!app) {
+ DBG("Application socket %d is being teardown. Abort event notify",
+ sock);
+ ret = 0;
+ goto error_rcu_unlock;
+ }
/* Lookup channel by UST object descriptor. Should always be found. */
ua_chan = find_channel_by_objd(app, cobjd);
assert(ua_chan->session);
ua_sess = ua_chan->session;
- pthread_mutex_lock(&ua_sess->registry.lock);
+ registry = get_session_registry(ua_sess);
+ assert(registry);
+
+ if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
+ chan_reg_key = ua_chan->tracing_channel_id;
+ } else {
+ chan_reg_key = ua_chan->key;
+ }
+
+ pthread_mutex_lock(®istry->lock);
- ret_code = ust_registry_create_event(&ua_sess->registry, &ua_chan->registry, sobjd, cobjd,
- name, sig, nr_fields, fields, loglevel, model_emf_uri, &event_id);
+ ret_code = ust_registry_create_event(registry, chan_reg_key,
+ sobjd, cobjd, name, sig, nr_fields, fields, loglevel,
+ model_emf_uri, ua_sess->buffer_type, &event_id);
/*
* The return value is returned to ustctl so in case of an error, the
goto error;
}
+ DBG3("UST registry event %s with id %" PRId32 " added successfully",
+ name, event_id);
+
error:
- pthread_mutex_unlock(&ua_sess->registry.lock);
+ pthread_mutex_unlock(®istry->lock);
+error_rcu_unlock:
rcu_read_unlock();
return ret;
}
+/*
+ * Handle application notification through the given notify socket.
+ *
+ * Return 0 on success or else a negative value.
+ */
int ust_app_recv_notify(int sock)
{
int ret;
error:
return ret;
}
+
+/*
+ * Once the notify socket hangs up, this is called. First, it tries to find the
+ * corresponding application. On failure, the call_rcu to close the socket is
+ * executed. If an application is found, it tries to delete it from the notify
+ * socket hash table. Whathever the result, it proceeds to the call_rcu.
+ *
+ * Note that an object needs to be allocated here so on ENOMEM failure, the
+ * call RCU is not done but the rest of the cleanup is.
+ */
+void ust_app_notify_sock_unregister(int sock)
+{
+ int err_enomem = 0;
+ struct lttng_ht_iter iter;
+ struct ust_app *app;
+ struct ust_app_notify_sock_obj *obj;
+
+ assert(sock >= 0);
+
+ rcu_read_lock();
+
+ obj = zmalloc(sizeof(*obj));
+ if (!obj) {
+ /*
+ * An ENOMEM is kind of uncool. If this strikes we continue the
+ * procedure but the call_rcu will not be called. In this case, we
+ * accept the fd leak rather than possibly creating an unsynchronized
+ * state between threads.
+ *
+ * TODO: The notify object should be created once the notify socket is
+ * registered and stored independantely from the ust app object. The
+ * tricky part is to synchronize the teardown of the application and
+ * this notify object. Let's keep that in mind so we can avoid this
+ * kind of shenanigans with ENOMEM in the teardown path.
+ */
+ err_enomem = 1;
+ } else {
+ obj->fd = sock;
+ }
+
+ DBG("UST app notify socket unregister %d", sock);
+
+ /*
+ * Lookup application by notify socket. If this fails, this means that the
+ * hash table delete has already been done by the application
+ * unregistration process so we can safely close the notify socket in a
+ * call RCU.
+ */
+ app = find_app_by_notify_sock(sock);
+ if (!app) {
+ goto close_socket;
+ }
+
+ iter.iter.node = &app->notify_sock_n.node;
+
+ /*
+ * Whatever happens here either we fail or succeed, in both cases we have
+ * to close the socket after a grace period to continue to the call RCU
+ * here. If the deletion is successful, the application is not visible
+ * anymore by other threads and is it fails it means that it was already
+ * deleted from the hash table so either way we just have to close the
+ * socket.
+ */
+ (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
+
+close_socket:
+ rcu_read_unlock();
+
+ /*
+ * Close socket after a grace period to avoid for the socket to be reused
+ * before the application object is freed creating potential race between
+ * threads trying to add unique in the global hash table.
+ */
+ if (!err_enomem) {
+ call_rcu(&obj->head, close_notify_sock_rcu);
+ }
+}
projects / lttng-tools.git / blobdiff