Separate session info from channel info in notification thread

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/include/Makefile.am b/include/Makefile.am
index 7a3535b3049d21e730d7205ad1c543cf35be1767..ab4665d5ba6f0d370dbed46fef9391a2c3e3faff 100644 (file)
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -112,4 +112,5 @@ noinst_HEADERS = \
        lttng/endpoint-internal.h \
        lttng/notification/channel-internal.h \
        lttng/channel-internal.h \
        lttng/endpoint-internal.h \
        lttng/notification/channel-internal.h \
        lttng/channel-internal.h \

-       lttng/rotate-internal.h
+       lttng/rotate-internal.h \
+       lttng/ref-internal.h

diff --git a/include/lttng/ref-internal.h b/include/lttng/ref-internal.h
new file mode 100644 (file)
index 0000000..4ecb2e2
--- /dev/null
+++ b/include/lttng/ref-internal.h
@@ -0,0 +1,62 @@
+#ifndef LTTNG_REF_INTERNAL_H
+#define LTTNG_REF_INTERNAL_H
+
+/*
+ * LTTng - Non thread-safe reference counting
+ *
+ * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <assert.h>
+
+typedef void (*lttng_release_func)(void *);
+
+struct lttng_ref {
+       unsigned long count;
+       lttng_release_func release;
+};
+
+static inline
+void lttng_ref_init(struct lttng_ref *ref, lttng_release_func release)
+{
+       assert(ref);
+       ref->count = 1;
+       ref->release = release;
+}
+
+static inline
+void lttng_ref_get(struct lttng_ref *ref)
+{
+       assert(ref);
+       ref->count++;
+       /* Overflow check. */
+       assert(ref->count);
+}
+
+static inline
+void lttng_ref_put(struct lttng_ref *ref)
+{
+       assert(ref);
+       /* Underflow check. */
+       assert(ref->count);
+       if (caa_unlikely((--ref->count) == 0)) {
+               ref->release(ref);
+       }
+}
+
+#endif /* LTTNG_REF_INTERNAL_H */

diff --git a/src/bin/lttng-sessiond/Makefile.am b/src/bin/lttng-sessiond/Makefile.am
index 4da4e6bab15cff2ef5cb467a4ad2a50f9fa5825b..f256aadb2477903cbc32f2aa3f1eeaa92289dd8d 100644 (file)
--- a/src/bin/lttng-sessiond/Makefile.am
+++ b/src/bin/lttng-sessiond/Makefile.am
@@ -33,6 +33,7 @@ lttng_sessiond_SOURCES = utils.c utils.h \
                        load-session-thread.h load-session-thread.c \
                        syscall.h syscall.c \
                        notification-thread.h notification-thread.c \
                        load-session-thread.h load-session-thread.c \
                        syscall.h syscall.c \
                        notification-thread.h notification-thread.c \

+                       notification-thread-internal.h \

                        notification-thread-commands.h notification-thread-commands.c \
                        notification-thread-events.h notification-thread-events.c \
                        sessiond-config.h sessiond-config.c \
                        notification-thread-commands.h notification-thread-commands.c \
                        notification-thread-events.h notification-thread-events.c \
                        sessiond-config.h sessiond-config.c \

diff --git a/src/bin/lttng-sessiond/notification-thread-commands.c b/src/bin/lttng-sessiond/notification-thread-commands.c
index cca667476b2efffd32ac520ba1e764198a538328..c142e849b3e234703b9dc6102f37f4a01e904ee9 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-commands.c
+++ b/src/bin/lttng-sessiond/notification-thread-commands.c
@@ -123,13 +123,13 @@ enum lttng_error_code notification_thread_command_add_channel(
        init_notification_thread_command(&cmd);
 
        cmd.type = NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL;
        init_notification_thread_command(&cmd);
 
        cmd.type = NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL;

-       cmd.parameters.add_channel.session_name = session_name;
-       cmd.parameters.add_channel.uid = uid;
-       cmd.parameters.add_channel.gid = gid;
-       cmd.parameters.add_channel.channel_name = channel_name;
-       cmd.parameters.add_channel.key.key = key;
-       cmd.parameters.add_channel.key.domain = domain;
-       cmd.parameters.add_channel.capacity = capacity;
+       cmd.parameters.add_channel.session.name = session_name;
+       cmd.parameters.add_channel.session.uid = uid;
+       cmd.parameters.add_channel.session.gid = gid;
+       cmd.parameters.add_channel.channel.name = channel_name;
+       cmd.parameters.add_channel.channel.key = key;
+       cmd.parameters.add_channel.channel.domain = domain;
+       cmd.parameters.add_channel.channel.capacity = capacity;

 
        ret = run_command_wait(handle, &cmd);
        if (ret) {
 
        ret = run_command_wait(handle, &cmd);
        if (ret) {

diff --git a/src/bin/lttng-sessiond/notification-thread-commands.h b/src/bin/lttng-sessiond/notification-thread-commands.h
index 8885d4faf57d639965b3f5326c50d81a9ba7099d..5c6441542ac091a742197b337807429386ecf4cf 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-commands.h
+++ b/src/bin/lttng-sessiond/notification-thread-commands.h
@@ -22,6 +22,8 @@
 #include <lttng/lttng-error.h>
 #include <urcu/rculfhash.h>
 #include "notification-thread.h"
 #include <lttng/lttng-error.h>
 #include <urcu/rculfhash.h>
 #include "notification-thread.h"

+#include "notification-thread-internal.h"
+#include "notification-thread-events.h"

 #include <common/waiter.h>
 
 struct notification_thread_data;
 #include <common/waiter.h>
 
 struct notification_thread_data;


@@ -35,21 +37,6 @@ enum notification_thread_command_type {
        NOTIFICATION_COMMAND_TYPE_QUIT,
 };
 
        NOTIFICATION_COMMAND_TYPE_QUIT,
 };
 

-struct channel_key {
-       uint64_t key;
-       enum lttng_domain_type domain;
-};
-
-struct channel_info {
-       struct channel_key key;
-       char *session_name;
-       uid_t uid;
-       gid_t gid;
-       char *channel_name;
-       uint64_t capacity;
-       struct cds_lfht_node channels_ht_node;
-};
-

 struct notification_thread_command {
        struct cds_list_head cmd_list_node;
 
 struct notification_thread_command {
        struct cds_list_head cmd_list_node;
 


@@ -58,7 +45,19 @@ struct notification_thread_command {
                /* Register/Unregister trigger. */
                struct lttng_trigger *trigger;
                /* Add channel. */
                /* Register/Unregister trigger. */
                struct lttng_trigger *trigger;
                /* Add channel. */

-               struct channel_info add_channel;
+               struct {
+                       struct {
+                               const char *name;
+                               uid_t uid;
+                               gid_t gid;
+                       } session;
+                       struct {
+                               const char *name;
+                               enum lttng_domain_type domain;
+                               uint64_t key;
+                               uint64_t capacity;
+                       } channel;
+               } add_channel;

                /* Remove channel. */
                struct {
                        uint64_t key;
                /* Remove channel. */
                struct {
                        uint64_t key;

diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c
index 6d5e625fc12f1dc5aa0544fab19dd7f0425e117d..254aa5396e5d30c102e771545773645ad766311c 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread-events.c
+++ b/src/bin/lttng-sessiond/notification-thread-events.c
@@ -168,6 +168,23 @@ int send_evaluation_to_clients(struct lttng_trigger *trigger,
                struct notification_thread_state *state,
                uid_t channel_uid, gid_t channel_gid);
 
                struct notification_thread_state *state,
                uid_t channel_uid, gid_t channel_gid);
 

+
+static
+void session_info_destroy(void *_data);
+static
+void session_info_get(struct session_info *session_info);
+static
+void session_info_put(struct session_info *session_info);
+static
+struct session_info *session_info_create(const char *name,
+               uid_t uid, gid_t gid);
+static
+void session_info_add_channel(struct session_info *session_info,
+               struct channel_info *channel_info);
+static
+void session_info_remove_channel(struct session_info *session_info,
+               struct channel_info *channel_info);
+

 static
 int match_client(struct cds_lfht_node *node, const void *key)
 {
 static
 int match_client(struct cds_lfht_node *node, const void *key)
 {


@@ -339,45 +356,136 @@ void channel_info_destroy(struct channel_info *channel_info)
                return;
        }
 
                return;
        }
 

-       if (channel_info->session_name) {
-               free(channel_info->session_name);
+       if (channel_info->session_info) {
+               session_info_remove_channel(channel_info->session_info,
+                               channel_info);
+               session_info_put(channel_info->session_info);

        }
        }

-       if (channel_info->channel_name) {
-               free(channel_info->channel_name);
+       if (channel_info->name) {
+               free(channel_info->name);

        }
        free(channel_info);
 }
 
        }
        free(channel_info);
 }
 

+/* Don't call directly, use the ref-counting mechanism. */

 static
 static

-struct channel_info *channel_info_copy(struct channel_info *channel_info)
+void session_info_destroy(void *_data)

 {
 {

-       struct channel_info *copy = zmalloc(sizeof(*channel_info));
+       struct session_info *session_info = _data;

 
 

-       assert(channel_info);
-       assert(channel_info->session_name);
-       assert(channel_info->channel_name);
+       assert(session_info);
+       if (session_info->channel_infos_ht) {
+               cds_lfht_destroy(session_info->channel_infos_ht, NULL);
+       }
+       free(session_info->name);
+       free(session_info);
+}

 
 

-       if (!copy) {
-               goto end;
+static
+void session_info_get(struct session_info *session_info)
+{
+       if (!session_info) {
+               return;
+       }
+       lttng_ref_get(&session_info->ref);
+}
+
+static
+void session_info_put(struct session_info *session_info)
+{
+       if (!session_info) {
+               return;

        }
        }

+       lttng_ref_put(&session_info->ref);
+}
+
+static
+struct session_info *session_info_create(const char *name, uid_t uid, gid_t gid)
+{
+       struct session_info *session_info;

 
 

-       memcpy(copy, channel_info, sizeof(*channel_info));
-       copy->session_name = NULL;
-       copy->channel_name = NULL;
+       assert(name);

 
 

-       copy->session_name = strdup(channel_info->session_name);
-       if (!copy->session_name) {
+       session_info = zmalloc(sizeof(*session_info));
+       if (!session_info) {
+               goto end;
+       }
+       lttng_ref_init(&session_info->ref, session_info_destroy);
+
+       session_info->channel_infos_ht = cds_lfht_new(DEFAULT_HT_SIZE,
+                       1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+       if (!session_info->channel_infos_ht) {

                goto error;
        }
                goto error;
        }

-       copy->channel_name = strdup(channel_info->channel_name);
-       if (!copy->channel_name) {
+
+       cds_lfht_node_init(&session_info->sessions_ht_node);
+       session_info->name = strdup(name);
+       if (!session_info->name) {

                goto error;
        }
                goto error;
        }

+       session_info->uid = uid;
+       session_info->gid = gid;
+end:
+       return session_info;
+error:
+       session_info_put(session_info);
+       return NULL;
+}
+
+static
+void session_info_add_channel(struct session_info *session_info,
+               struct channel_info *channel_info)
+{
+       rcu_read_lock();
+       cds_lfht_add(session_info->channel_infos_ht,
+                       hash_channel_key(&channel_info->key),
+                       &channel_info->session_info_channels_ht_node);
+       rcu_read_unlock();
+}
+
+static
+void session_info_remove_channel(struct session_info *session_info,
+               struct channel_info *channel_info)
+{
+       rcu_read_lock();
+       cds_lfht_del(session_info->channel_infos_ht,
+                       &channel_info->session_info_channels_ht_node);
+       rcu_read_unlock();
+}
+
+static
+struct channel_info *channel_info_create(const char *channel_name,
+               struct channel_key *channel_key, uint64_t channel_capacity,
+               struct session_info *session_info)
+{
+       struct channel_info *channel_info = zmalloc(sizeof(*channel_info));
+
+       if (!channel_info) {
+               goto end;
+       }
+

        cds_lfht_node_init(&channel_info->channels_ht_node);
        cds_lfht_node_init(&channel_info->channels_ht_node);

+       cds_lfht_node_init(&channel_info->session_info_channels_ht_node);
+       memcpy(&channel_info->key, channel_key, sizeof(*channel_key));
+       channel_info->capacity = channel_capacity;
+
+       channel_info->name = strdup(channel_name);
+       if (!channel_info->name) {
+               goto error;
+       }
+
+       /*
+        * Set the references between session and channel infos:
+        *   - channel_info holds a strong reference to session_info
+        *   - session_info holds a weak reference to channel_info
+        */
+       session_info_get(session_info);
+       session_info_add_channel(session_info, channel_info);
+       channel_info->session_info = session_info;

 end:
 end:

-       return copy;
+       return channel_info;

 error:
 error:

-       channel_info_destroy(copy);
+       channel_info_destroy(channel_info);

        return NULL;
 }
 
        return NULL;
 }
 


@@ -495,7 +603,8 @@ int evaluate_condition_for_client(struct lttng_trigger *trigger,
        /* Send evaluation result to the newly-subscribed client. */
        DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
        ret = send_evaluation_to_clients(trigger, evaluation, &client_list,
        /* Send evaluation result to the newly-subscribed client. */
        DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
        ret = send_evaluation_to_clients(trigger, evaluation, &client_list,

-                       state, channel_info->uid, channel_info->gid);
+                       state, channel_info->session_info->uid,
+                       channel_info->session_info->gid);

 
 end:
        return ret;
 
 end:
        return ret;


@@ -736,7 +845,7 @@ end:
 
 static
 bool trigger_applies_to_channel(struct lttng_trigger *trigger,
 
 static
 bool trigger_applies_to_channel(struct lttng_trigger *trigger,

-               struct channel_info *info)
+               struct channel_info *channel_info)

 {
        enum lttng_condition_status status;
        struct lttng_condition *condition;
 {
        enum lttng_condition_status status;
        struct lttng_condition *condition;


@@ -760,7 +869,7 @@ bool trigger_applies_to_channel(struct lttng_trigger *trigger,
        status = lttng_condition_buffer_usage_get_domain_type(condition,
                        &trigger_domain);
        assert(status == LTTNG_CONDITION_STATUS_OK);
        status = lttng_condition_buffer_usage_get_domain_type(condition,
                        &trigger_domain);
        assert(status == LTTNG_CONDITION_STATUS_OK);

-       if (info->key.domain != trigger_domain) {
+       if (channel_info->key.domain != trigger_domain) {

                goto fail;
        }
 
                goto fail;
        }
 


@@ -772,10 +881,10 @@ bool trigger_applies_to_channel(struct lttng_trigger *trigger,
                        condition, &trigger_channel_name);
        assert((status == LTTNG_CONDITION_STATUS_OK) && trigger_channel_name);
 
                        condition, &trigger_channel_name);
        assert((status == LTTNG_CONDITION_STATUS_OK) && trigger_channel_name);
 

-       if (strcmp(info->session_name, trigger_session_name)) {
+       if (strcmp(channel_info->session_info->name, trigger_session_name)) {

                goto fail;
        }
                goto fail;
        }

-       if (strcmp(info->channel_name, trigger_channel_name)) {
+       if (strcmp(channel_info->name, trigger_channel_name)) {

                goto fail;
        }
 
                goto fail;
        }
 


@@ -803,32 +912,91 @@ bool trigger_applies_to_client(struct lttng_trigger *trigger,
        return applies;
 }
 
        return applies;
 }
 

+static
+int match_session(struct cds_lfht_node *node, const void *key)
+{
+       const char *name = key;
+       struct session_info *session_info = caa_container_of(
+               node, struct session_info, sessions_ht_node);
+
+       return !strcmp(session_info->name, name);
+}
+
+static
+struct session_info *find_or_create_session_info(
+               struct notification_thread_state *state,
+               const char *name, uid_t uid, gid_t gid)
+{
+       struct session_info *session = NULL;
+       struct cds_lfht_node *node;
+       struct cds_lfht_iter iter;
+
+       rcu_read_lock();
+       cds_lfht_lookup(state->sessions_ht,
+                       hash_key_str(name, lttng_ht_seed),
+                       match_session,
+                       name,
+                       &iter);
+       node = cds_lfht_iter_get_node(&iter);
+       if (node) {
+               DBG("[notification-thread] Found session info of session \"%s\" (uid = %i, gid = %i)",
+                               name, uid, gid);
+               session = caa_container_of(node, struct session_info,
+                               sessions_ht_node);
+               assert(session->uid == uid);
+               assert(session->gid == gid);
+               goto end;
+       }
+
+       session = session_info_create(name, uid, gid);
+       if (!session) {
+               ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
+                               name, uid, gid);
+               goto end;
+       }
+end:
+       rcu_read_unlock();
+       return session;
+}
+

 static
 int handle_notification_thread_command_add_channel(
 static
 int handle_notification_thread_command_add_channel(

-       struct notification_thread_state *state,
-       struct channel_info *channel_info,
-       enum lttng_error_code *cmd_result)
+               struct notification_thread_state *state,
+               const char *session_name, uid_t session_uid, gid_t session_gid,
+               const char *channel_name, enum lttng_domain_type channel_domain,
+               uint64_t channel_key_int, uint64_t channel_capacity,
+               enum lttng_error_code *cmd_result)

 {
        struct cds_list_head trigger_list;
 {
        struct cds_list_head trigger_list;

-       struct channel_info *new_channel_info;
-       struct channel_key *channel_key;
+       struct channel_info *new_channel_info = NULL;
+       struct channel_key channel_key = {
+               .key = channel_key_int,
+               .domain = channel_domain,
+       };

        struct lttng_channel_trigger_list *channel_trigger_list = NULL;
        struct lttng_trigger_ht_element *trigger_ht_element = NULL;
        int trigger_count = 0;
        struct cds_lfht_iter iter;
        struct lttng_channel_trigger_list *channel_trigger_list = NULL;
        struct lttng_trigger_ht_element *trigger_ht_element = NULL;
        int trigger_count = 0;
        struct cds_lfht_iter iter;

+       struct session_info *session_info = NULL;

 
        DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64 " in %s domain",
 
        DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64 " in %s domain",

-                       channel_info->channel_name, channel_info->session_name,
-                       channel_info->key.key, channel_info->key.domain == LTTNG_DOMAIN_KERNEL ? "kernel" : "user space");
+                       channel_name, session_name, channel_key_int,
+                       channel_domain == LTTNG_DOMAIN_KERNEL ? "kernel" : "user space");

 
        CDS_INIT_LIST_HEAD(&trigger_list);
 
 
        CDS_INIT_LIST_HEAD(&trigger_list);
 

-       new_channel_info = channel_info_copy(channel_info);
-       if (!new_channel_info) {
+       session_info = find_or_create_session_info(state, session_name,
+                       session_uid, session_gid);
+       if (!session_info) {
+               /* Allocation error or an internal error occured. */

                goto error;
        }
 
                goto error;
        }
 

-       channel_key = &new_channel_info->key;
+       new_channel_info = channel_info_create(channel_name, &channel_key,
+                       channel_capacity, session_info);
+       if (!new_channel_info) {
+               goto error;
+       }

 
        /* Build a list of all triggers applying to the new channel. */
        cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element,
 
        /* Build a list of all triggers applying to the new channel. */
        cds_lfht_for_each_entry(state->triggers_ht, &iter, trigger_ht_element,


@@ -836,7 +1004,7 @@ int handle_notification_thread_command_add_channel(
                struct lttng_trigger_list_element *new_element;
 
                if (!trigger_applies_to_channel(trigger_ht_element->trigger,
                struct lttng_trigger_list_element *new_element;
 
                if (!trigger_applies_to_channel(trigger_ht_element->trigger,

-                               channel_info)) {
+                               new_channel_info)) {

                        continue;
                }
 
                        continue;
                }
 


@@ -856,7 +1024,7 @@ int handle_notification_thread_command_add_channel(
        if (!channel_trigger_list) {
                goto error;
        }
        if (!channel_trigger_list) {
                goto error;
        }

-       channel_trigger_list->channel_key = *channel_key;
+       channel_trigger_list->channel_key = new_channel_info->key;

        CDS_INIT_LIST_HEAD(&channel_trigger_list->list);
        cds_lfht_node_init(&channel_trigger_list->channel_triggers_ht_node);
        cds_list_splice(&trigger_list, &channel_trigger_list->list);
        CDS_INIT_LIST_HEAD(&channel_trigger_list->list);
        cds_lfht_node_init(&channel_trigger_list->channel_triggers_ht_node);
        cds_list_splice(&trigger_list, &channel_trigger_list->list);


@@ -864,21 +1032,21 @@ int handle_notification_thread_command_add_channel(
        rcu_read_lock();
        /* Add channel to the channel_ht which owns the channel_infos. */
        cds_lfht_add(state->channels_ht,
        rcu_read_lock();
        /* Add channel to the channel_ht which owns the channel_infos. */
        cds_lfht_add(state->channels_ht,

-                       hash_channel_key(channel_key),
+                       hash_channel_key(&new_channel_info->key),

                        &new_channel_info->channels_ht_node);
        /*
         * Add the list of triggers associated with this channel to the
         * channel_triggers_ht.
         */
        cds_lfht_add(state->channel_triggers_ht,
                        &new_channel_info->channels_ht_node);
        /*
         * Add the list of triggers associated with this channel to the
         * channel_triggers_ht.
         */
        cds_lfht_add(state->channel_triggers_ht,

-                       hash_channel_key(channel_key),
+                       hash_channel_key(&new_channel_info->key),

                        &channel_trigger_list->channel_triggers_ht_node);
        rcu_read_unlock();
        *cmd_result = LTTNG_OK;
        return 0;
 error:
                        &channel_trigger_list->channel_triggers_ht_node);
        rcu_read_unlock();
        *cmd_result = LTTNG_OK;
        return 0;
 error:

-       /* Empty trigger list */

        channel_info_destroy(new_channel_info);
        channel_info_destroy(new_channel_info);

+       session_info_put(session_info);

        return 1;
 }
 
        return 1;
 }
 


@@ -1021,9 +1189,9 @@ end:
  */
 static
 int handle_notification_thread_command_register_trigger(
  */
 static
 int handle_notification_thread_command_register_trigger(

-       struct notification_thread_state *state,
-       struct lttng_trigger *trigger,
-       enum lttng_error_code *cmd_result)
+               struct notification_thread_state *state,
+               struct lttng_trigger *trigger,
+               enum lttng_error_code *cmd_result)

 {
        int ret = 0;
        struct lttng_condition *condition;
 {
        int ret = 0;
        struct lttng_condition *condition;


@@ -1320,8 +1488,9 @@ int handle_notification_thread_command(
        uint64_t counter;
        struct notification_thread_command *cmd;
 
        uint64_t counter;
        struct notification_thread_command *cmd;
 

-       /* Read event_fd to put it back into a quiescent state. */
-       ret = read(lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), &counter, sizeof(counter));
+       /* Read the event pipe to put it back into a quiescent state. */
+       ret = read(lttng_pipe_get_readfd(handle->cmd_queue.event_pipe), &counter,
+                       sizeof(counter));

        if (ret == -1) {
                goto error;
        }
        if (ret == -1) {
                goto error;
        }


@@ -1345,7 +1514,14 @@ int handle_notification_thread_command(
        case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL:
                DBG("[notification-thread] Received add channel command");
                ret = handle_notification_thread_command_add_channel(
        case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL:
                DBG("[notification-thread] Received add channel command");
                ret = handle_notification_thread_command_add_channel(

-                               state, &cmd->parameters.add_channel,
+                               state,
+                               cmd->parameters.add_channel.session.name,
+                               cmd->parameters.add_channel.session.uid,
+                               cmd->parameters.add_channel.session.gid,
+                               cmd->parameters.add_channel.channel.name,
+                               cmd->parameters.add_channel.channel.domain,
+                               cmd->parameters.add_channel.channel.key,
+                               cmd->parameters.add_channel.channel.capacity,

                                &cmd->reply_code);
                break;
        case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL:
                                &cmd->reply_code);
                break;
        case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL:


@@ -2244,9 +2420,9 @@ int handle_notification_thread_channel_sample(
        channel_info = caa_container_of(node, struct channel_info,
                        channels_ht_node);
        DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64 ") in session %s (highest usage = %" PRIu64 ", lowest usage = %" PRIu64")",
        channel_info = caa_container_of(node, struct channel_info,
                        channels_ht_node);
        DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64 ") in session %s (highest usage = %" PRIu64 ", lowest usage = %" PRIu64")",

-                       channel_info->channel_name,
+                       channel_info->name,

                        latest_sample.key.key,
                        latest_sample.key.key,

-                       channel_info->session_name,
+                       channel_info->session_info->name,

                        latest_sample.highest_usage,
                        latest_sample.lowest_usage);
 
                        latest_sample.highest_usage,
                        latest_sample.lowest_usage);
 


@@ -2356,7 +2532,9 @@ int handle_notification_thread_channel_sample(
                /* Dispatch evaluation result to all clients. */
                ret = send_evaluation_to_clients(trigger_list_element->trigger,
                                evaluation, client_list, state,
                /* Dispatch evaluation result to all clients. */
                ret = send_evaluation_to_clients(trigger_list_element->trigger,
                                evaluation, client_list, state,

-                               channel_info->uid, channel_info->gid);
+                               channel_info->session_info->uid,
+                               channel_info->session_info->gid);
+               lttng_evaluation_destroy(evaluation);

                if (ret) {
                        goto end_unlock;
                }
                if (ret) {
                        goto end_unlock;
                }

diff --git a/src/bin/lttng-sessiond/notification-thread-internal.h b/src/bin/lttng-sessiond/notification-thread-internal.h
new file mode 100644 (file)
index 0000000..8149e2c
--- /dev/null
+++ b/src/bin/lttng-sessiond/notification-thread-internal.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License, version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef NOTIFICATION_THREAD_INTERNAL_H
+#define NOTIFICATION_THREAD_INTERNAL_H
+
+#include <lttng/ref-internal.h>
+#include <urcu/rculfhash.h>
+#include <unistd.h>
+
+struct channel_key {
+       uint64_t key;
+       enum lttng_domain_type domain;
+};
+
+struct session_info {
+       struct lttng_ref ref;
+       char *name;
+       uid_t uid;
+       gid_t gid;
+       /*
+        * Back-ref (weak) to all channels in this session.
+        * The hashtable's key is a hash of (struct channel_key) and
+        * the value is of type (struct channel_info *).
+        */
+       struct cds_lfht *channel_infos_ht;
+       /* Node in the notification thread state's sessions_ht. */
+       struct cds_lfht_node sessions_ht_node;
+};
+
+struct channel_info {
+       struct channel_key key;
+       char *name;
+       uint64_t capacity;
+       /*
+        * A channel info holds a reference (lttng_ref) on session_info.
+        * session_info, in return, holds a weak reference to the channel.
+        */
+       struct session_info *session_info;
+       /* Node in the notification thread state's channels_ht. */
+       struct cds_lfht_node channels_ht_node;
+       /* Node in the session_info's channels_ht. */
+       struct cds_lfht_node session_info_channels_ht_node;
+};
+
+#endif /* NOTIFICATION_THREAD_INTERNAL_H */

diff --git a/src/bin/lttng-sessiond/notification-thread.c b/src/bin/lttng-sessiond/notification-thread.c
index 92ac597fa00a58e7720f6710579df372c22cd6a6..62d47ee54182cfc3da2a27d3dbf4ba37638a67f4 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread.c
+++ b/src/bin/lttng-sessiond/notification-thread.c
@@ -350,11 +350,13 @@ void fini_thread_state(struct notification_thread_state *state)
                assert(!ret);
        }
        if (state->channels_ht) {
                assert(!ret);
        }
        if (state->channels_ht) {

-               ret = cds_lfht_destroy(state->channels_ht,
-                               NULL);
+               ret = cds_lfht_destroy(state->channels_ht, NULL);
+               assert(!ret);
+       }
+       if (state->sessions_ht) {
+               ret = cds_lfht_destroy(state->sessions_ht, NULL);

                assert(!ret);
        }
                assert(!ret);
        }

-

        if (state->notification_channel_socket >= 0) {
                notification_channel_socket_destroy(
                                state->notification_channel_socket);
        if (state->notification_channel_socket >= 0) {
                notification_channel_socket_destroy(
                                state->notification_channel_socket);


@@ -420,7 +422,11 @@ int init_thread_state(struct notification_thread_handle *handle,
        if (!state->channels_ht) {
                goto error;
        }
        if (!state->channels_ht) {
                goto error;
        }

-
+       state->sessions_ht = cds_lfht_new(DEFAULT_HT_SIZE,
+                       1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+       if (!state->sessions_ht) {
+               goto error;
+       }

        state->triggers_ht = cds_lfht_new(DEFAULT_HT_SIZE,
                        1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
        if (!state->triggers_ht) {
        state->triggers_ht = cds_lfht_new(DEFAULT_HT_SIZE,
                        1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
        if (!state->triggers_ht) {

diff --git a/src/bin/lttng-sessiond/notification-thread.h b/src/bin/lttng-sessiond/notification-thread.h
index c2793b76aab06d5ceb43692fe90ca65989e9de7d..011ffbfaed7b71f5287e11787b4ab0014f108201 100644 (file)
--- a/src/bin/lttng-sessiond/notification-thread.h
+++ b/src/bin/lttng-sessiond/notification-thread.h
@@ -88,6 +88,12 @@ struct notification_thread_handle {
  *             associates a channel_key to a struct channel_info. The hash table
  *             holds the ownership of the struct channel_info.
  *
  *             associates a channel_key to a struct channel_info. The hash table
  *             holds the ownership of the struct channel_info.
  *

+ *   - sessions_ht:
+ *             associates a session_name (hash) to a struct session_info. The
+ *             hash table holds no ownership of the struct session_info;
+ *             the session_info structure is owned by the session's various
+ *             channels through their struct channel_info (ref-counting is used).
+ *

  *   - triggers_ht:
  *             associates a condition to a struct lttng_trigger_ht_element.
  *             The hash table holds the ownership of the
  *   - triggers_ht:
  *             associates a condition to a struct lttng_trigger_ht_element.
  *             The hash table holds the ownership of the


@@ -110,7 +116,7 @@ struct notification_thread_handle {
  * 1) Creation of a tracing channel
  *    - notification_trigger_clients_ht is traversed to identify
  *      triggers which apply to this new channel,
  * 1) Creation of a tracing channel
  *    - notification_trigger_clients_ht is traversed to identify
  *      triggers which apply to this new channel,

- *    - triggers identified are added to the channel_triggers_ht.
+ *      - triggers identified are added to the channel_triggers_ht.

  *    - add channel to channels_ht
  *
  * 2) Destruction of a tracing channel
  *    - add channel to channels_ht
  *
  * 2) Destruction of a tracing channel


@@ -171,6 +177,7 @@ struct notification_thread_state {
        struct cds_lfht *channel_state_ht;
        struct cds_lfht *notification_trigger_clients_ht;
        struct cds_lfht *channels_ht;
        struct cds_lfht *channel_state_ht;
        struct cds_lfht *notification_trigger_clients_ht;
        struct cds_lfht *channels_ht;

+       struct cds_lfht *sessions_ht;

        struct cds_lfht *triggers_ht;
 };
 
        struct cds_lfht *triggers_ht;
 };