SoW-2020-0002: Trace Hit Counters: trigger error reporting integration
[lttng-tools.git] / src / bin / lttng-sessiond / notification-thread.c
index 92ac597fa00a58e7720f6710579df372c22cd6a6..5a7c0075aa1f24ae72592a1ce7adac61fa9b68e1 100644 (file)
@@ -1,18 +1,8 @@
 /*
- * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * 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.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * 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.
  */
 
 #define _LGPL_SOURCE
 #include "notification-thread-commands.h"
 #include "lttng-sessiond.h"
 #include "health-sessiond.h"
+#include "thread.h"
+#include "testpoint.h"
+
+#include "kernel.h"
+#include <common/kernel-ctl/kernel-ctl.h>
 
 #include <urcu.h>
 #include <urcu/list.h>
 #include <urcu/rculfhash.h>
 
+
+int trigger_consumption_paused;
 /*
  * Destroy the thread data previously created by the init function.
  */
@@ -56,6 +53,7 @@ void notification_thread_handle_destroy(
 
        assert(cds_list_empty(&handle->cmd_queue.list));
        pthread_mutex_destroy(&handle->cmd_queue.lock);
+       sem_destroy(&handle->ready);
 
        if (handle->cmd_queue.event_pipe) {
                lttng_pipe_destroy(handle->cmd_queue.event_pipe);
@@ -78,14 +76,21 @@ void notification_thread_handle_destroy(
                        PERROR("close kernel consumer channel monitoring pipe");
                }
        }
+
 end:
        free(handle);
 }
 
+/*
+ * TODO: refactor this if needed. Lifetime of the kernel notification event source.
+ * The kernel_notification_monitor_fd ownwership remain to the main thread.
+ * This is because we need to close this fd before removing the modules.
+ */
 struct notification_thread_handle *notification_thread_handle_create(
                struct lttng_pipe *ust32_channel_monitor_pipe,
                struct lttng_pipe *ust64_channel_monitor_pipe,
-               struct lttng_pipe *kernel_channel_monitor_pipe)
+               struct lttng_pipe *kernel_channel_monitor_pipe,
+               int kernel_notification_monitor_fd)
 {
        int ret;
        struct notification_thread_handle *handle;
@@ -96,6 +101,8 @@ struct notification_thread_handle *notification_thread_handle_create(
                goto end;
        }
 
+       sem_init(&handle->ready, 0, 0);
+
        event_pipe = lttng_pipe_open(FD_CLOEXEC);
        if (!event_pipe) {
                ERR("event_pipe creation");
@@ -141,6 +148,12 @@ struct notification_thread_handle *notification_thread_handle_create(
        } else {
                handle->channel_monitoring_pipes.kernel_consumer = -1;
        }
+
+       CDS_INIT_LIST_HEAD(&handle->event_trigger_sources.list);
+       ret = pthread_mutex_init(&handle->event_trigger_sources.lock, NULL);
+       if (ret) {
+               goto error;
+       }
 end:
        return handle;
 error:
@@ -168,7 +181,7 @@ char *get_notification_channel_sock_path(void)
                        goto error;
                }
        } else {
-               char *home_path = utils_get_home_dir();
+               const char *home_path = utils_get_home_dir();
 
                if (!home_path) {
                        ERR("Can't get HOME directory for socket creation");
@@ -235,8 +248,16 @@ int notification_channel_socket_create(void)
        }
 
        if (getuid() == 0) {
-               ret = chown(sock_path, 0,
-                               utils_get_group_id(config.tracing_group_name.value));
+               gid_t gid;
+
+               ret =  utils_get_group_id(config.tracing_group_name.value, true,
+                               &gid);
+               if (ret) {
+                       /* Default to root group. */
+                       gid = 0;
+               }
+
+               ret = chown(sock_path, 0, gid);
                if (ret) {
                        ERR("Failed to set the notification channel socket's group");
                        ret = -1;
@@ -303,7 +324,7 @@ int init_poll_set(struct lttng_poll_event *poll_set,
                goto error;
        }
        if (handle->channel_monitoring_pipes.kernel_consumer < 0) {
-               goto end;
+               goto skip_kernel_consumer;
        }
        ret = lttng_poll_add(poll_set,
                        handle->channel_monitoring_pipes.kernel_consumer,
@@ -312,6 +333,8 @@ int init_poll_set(struct lttng_poll_event *poll_set,
                ERR("[notification-thread] Failed to add kernel channel monitoring pipe fd to pollset");
                goto error;
        }
+
+skip_kernel_consumer:
 end:
        return ret;
 error:
@@ -330,6 +353,10 @@ void fini_thread_state(struct notification_thread_state *state)
                ret = cds_lfht_destroy(state->client_socket_ht, NULL);
                assert(!ret);
        }
+       if (state->client_id_ht) {
+               ret = cds_lfht_destroy(state->client_id_ht, NULL);
+               assert(!ret);
+       }
        if (state->triggers_ht) {
                ret = handle_notification_thread_trigger_unregister_all(state);
                assert(!ret);
@@ -350,18 +377,54 @@ void fini_thread_state(struct notification_thread_state *state)
                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);
+       }
+       if (state->triggers_by_name_uid_ht) {
+               ret = cds_lfht_destroy(state->triggers_by_name_uid_ht, NULL);
+               assert(!ret);
+       }
+       if (state->trigger_tokens_ht) {
+               ret = cds_lfht_destroy(state->trigger_tokens_ht, NULL);
+               assert(!ret);
+       }
+       /*
+        * Must be destroyed after all channels have been destroyed.
+        * See comment in struct lttng_session_trigger_list.
+        */
+       if (state->session_triggers_ht) {
+               ret = cds_lfht_destroy(state->session_triggers_ht, NULL);
                assert(!ret);
        }
-
        if (state->notification_channel_socket >= 0) {
                notification_channel_socket_destroy(
                                state->notification_channel_socket);
        }
+       if (state->executor) {
+               action_executor_destroy(state->executor);
+       }
        lttng_poll_clean(&state->events);
 }
 
+static
+void mark_thread_as_ready(struct notification_thread_handle *handle)
+{
+       DBG("Marking notification thread as ready");
+       sem_post(&handle->ready);
+}
+
+static
+void wait_until_thread_is_ready(struct notification_thread_handle *handle)
+{
+       DBG("Waiting for notification thread to be ready");
+       sem_wait(&handle->ready);
+       DBG("Notification thread is ready");
+}
+
 static
 int init_thread_state(struct notification_thread_handle *handle,
                struct notification_thread_state *state)
@@ -370,6 +433,7 @@ int init_thread_state(struct notification_thread_handle *handle,
 
        memset(state, 0, sizeof(*state));
        state->notification_channel_socket = -1;
+       state->trigger_id.token_generator = 1;
        lttng_poll_init(&state->events);
 
        ret = notification_channel_socket_create();
@@ -397,12 +461,24 @@ int init_thread_state(struct notification_thread_handle *handle,
                goto error;
        }
 
+       state->client_id_ht = cds_lfht_new(DEFAULT_HT_SIZE, 1, 0,
+                       CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+       if (!state->client_id_ht) {
+               goto error;
+       }
+
        state->channel_triggers_ht = cds_lfht_new(DEFAULT_HT_SIZE, 1, 0,
                        CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
        if (!state->channel_triggers_ht) {
                goto error;
        }
 
+       state->session_triggers_ht = cds_lfht_new(DEFAULT_HT_SIZE, 1, 0,
+                       CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+       if (!state->session_triggers_ht) {
+               goto error;
+       }
+
        state->channel_state_ht = cds_lfht_new(DEFAULT_HT_SIZE, 1, 0,
                        CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
        if (!state->channel_state_ht) {
@@ -420,12 +496,32 @@ int init_thread_state(struct notification_thread_handle *handle,
        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) {
                goto error;
        }
+       state->triggers_by_name_uid_ht = cds_lfht_new(DEFAULT_HT_SIZE,
+                       1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+       if (!state->triggers_by_name_uid_ht) {
+               goto error;
+       }
+
+       state->trigger_tokens_ht = cds_lfht_new(DEFAULT_HT_SIZE,
+                       1, 0, CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
+       if (!state->trigger_tokens_ht) {
+               goto error;
+       }
+       state->executor = action_executor_create(handle);
+       if (!state->executor) {
+               goto error;
+       }
+       mark_thread_as_ready(handle);
 end:
        return 0;
 error:
@@ -469,27 +565,86 @@ end:
        return ret;
 }
 
+static int handle_trigger_event_pipe(int fd,
+               enum lttng_domain_type domain,
+               uint32_t revents,
+               struct notification_thread_state *state)
+{
+       int ret = 0;
+
+       if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+               ret = lttng_poll_del(&state->events, fd);
+               if (ret) {
+                       ERR("[notification-thread] Failed to remove event monitoring pipe from poll set");
+               }
+               goto end;
+       }
+
+       if (testpoint(sessiond_handle_trigger_event_pipe)) {
+               ret = 0;
+               goto end;
+       }
+
+       if (caa_unlikely(trigger_consumption_paused)) {
+               DBG("Trigger consumption paused, sleeping...");
+               sleep(1);
+               goto end;
+       }
+
+       ret = handle_notification_thread_event(state, fd, domain);
+       if (ret) {
+               ERR("[notification-thread] Event sample handling error occurred for fd: %d", fd);
+               ret = -1;
+               goto end;
+       }
+
+end:
+       return ret;
+}
+
+/*
+ * Return the event source domain type via parameter.
+ */
+static bool fd_is_event_source(struct notification_thread_handle *handle, int fd, enum lttng_domain_type *domain)
+{
+       struct notification_event_trigger_source_element *source_element, *tmp;
+
+       assert(domain);
+
+       cds_list_for_each_entry_safe(source_element, tmp,
+                       &handle->event_trigger_sources.list, node) {
+               if (source_element->fd != fd) {
+                       continue;
+               }
+               *domain = source_element->domain;
+               return true;
+       }
+       return false;
+}
+
 /*
  * This thread services notification channel clients and commands received
  * from various lttng-sessiond components over a command queue.
  */
+static
 void *thread_notification(void *data)
 {
        int ret;
        struct notification_thread_handle *handle = data;
        struct notification_thread_state state;
+       enum lttng_domain_type domain;
 
        DBG("[notification-thread] Started notification thread");
 
+       health_register(health_sessiond, HEALTH_SESSIOND_TYPE_NOTIFICATION);
+       rcu_register_thread();
+       rcu_thread_online();
+
        if (!handle) {
                ERR("[notification-thread] Invalid thread context provided");
                goto end;
        }
 
-       rcu_register_thread();
-       rcu_thread_online();
-
-       health_register(health_sessiond, HEALTH_SESSIOND_TYPE_NOTIFICATION);
        health_code_update();
 
        ret = init_thread_state(handle, &state);
@@ -497,8 +652,9 @@ void *thread_notification(void *data)
                goto end;
        }
 
-       /* Ready to handle client connections. */
-       sessiond_notify_ready();
+       if (testpoint(sessiond_thread_notification)) {
+               goto end;
+       }
 
        while (true) {
                int fd_count, i;
@@ -524,9 +680,6 @@ void *thread_notification(void *data)
                        int fd = LTTNG_POLL_GETFD(&state.events, i);
                        uint32_t revents = LTTNG_POLL_GETEV(&state.events, i);
 
-                       if (!revents) {
-                               continue;
-                       }
                        DBG("[notification-thread] Handling fd (%i) activity (%u)", fd, revents);
 
                        if (fd == state.notification_channel_socket) {
@@ -561,6 +714,11 @@ void *thread_notification(void *data)
                                if (ret) {
                                        goto error;
                                }
+                       } else if (fd_is_event_source(handle, fd, &domain)) {
+                               ret = handle_trigger_event_pipe(fd, domain, revents, &state);
+                               if (ret) {
+                                       goto error;
+                               }
                        } else {
                                /* Activity on a client's socket. */
                                if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
@@ -599,9 +757,43 @@ void *thread_notification(void *data)
 exit:
 error:
        fini_thread_state(&state);
-       health_unregister(health_sessiond);
+end:
        rcu_thread_offline();
        rcu_unregister_thread();
-end:
+       health_unregister(health_sessiond);
+       return NULL;
+}
+
+static
+bool shutdown_notification_thread(void *thread_data)
+{
+       struct notification_thread_handle *handle = thread_data;
+
+       notification_thread_command_quit(handle);
+       return true;
+}
+
+struct lttng_thread *launch_notification_thread(
+               struct notification_thread_handle *handle)
+{
+       struct lttng_thread *thread;
+
+       thread = lttng_thread_create("Notification",
+                       thread_notification,
+                       shutdown_notification_thread,
+                       NULL,
+                       handle);
+       if (!thread) {
+               goto error;
+       }
+
+       /*
+        * Wait for the thread to be marked as "ready" before returning
+        * as other subsystems depend on the notification subsystem
+        * (e.g. rotation thread).
+        */
+       wait_until_thread_is_ready(handle);
+       return thread;
+error:
        return NULL;
 }
This page took 0.029509 seconds and 5 git commands to generate.