X-Git-Url: https://git.liburcu.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread.c;h=5801682962e9add2c57d83c30a8fad3a210201e6;hp=9b2cd5b96a9139ad9cea7e934b4e84770167d40c;hb=38eb8a68a2817b040e31c577a9e3a81b52897816;hpb=e6887944f09a8985efb521ea638b4dfe557ff4ed

diff --git a/src/bin/lttng-sessiond/notification-thread.c b/src/bin/lttng-sessiond/notification-thread.c
index 9b2cd5b96..580168296 100644
--- a/src/bin/lttng-sessiond/notification-thread.c
+++ b/src/bin/lttng-sessiond/notification-thread.c
@@ -27,11 +27,17 @@
 #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 notifier_consumption_paused;
 /*
  * Destroy the thread data previously created by the init function.
  */
@@ -69,6 +75,7 @@ void notification_thread_handle_destroy(
 			PERROR("close kernel consumer channel monitoring pipe");
 		}
 	}
+
 end:
 	free(handle);
 }
@@ -134,6 +141,7 @@ struct notification_thread_handle *notification_thread_handle_create(
 	} else {
 		handle->channel_monitoring_pipes.kernel_consumer = -1;
 	}
+
 end:
 	return handle;
 error:
@@ -366,6 +374,10 @@ void fini_thread_state(struct notification_thread_state *state)
 		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.
@@ -378,6 +390,9 @@ void fini_thread_state(struct notification_thread_state *state)
 		notification_channel_socket_destroy(
 				state->notification_channel_socket);
 	}
+
+	assert(cds_list_empty(&state->tracer_event_sources_list));
+
 	if (state->executor) {
 		action_executor_destroy(state->executor);
 	}
@@ -486,10 +501,21 @@ int init_thread_state(struct notification_thread_handle *handle,
 		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;
+	}
+
+	CDS_INIT_LIST_HEAD(&state->tracer_event_sources_list);
+
 	state->executor = action_executor_create(handle);
 	if (!state->executor) {
 		goto error;
 	}
+
+	state->restart_poll = false;
+
 	mark_thread_as_ready(handle);
 end:
 	return 0;
@@ -534,6 +560,71 @@ end:
 	return ret;
 }
 
+static int handle_event_notification_pipe(int event_source_fd,
+		enum lttng_domain_type domain,
+		uint32_t revents,
+		struct notification_thread_state *state)
+{
+	int ret = 0;
+
+	if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
+		ret = handle_notification_thread_remove_tracer_event_source_no_result(
+				state, event_source_fd);
+		if (ret) {
+			ERR("[notification-thread] Failed to remove event notification pipe from poll set: fd = %d",
+					event_source_fd);
+		}
+		goto end;
+	}
+
+	if (testpoint(sessiond_handle_notifier_event_pipe)) {
+		ret = 0;
+		goto end;
+	}
+
+	if (caa_unlikely(notifier_consumption_paused)) {
+		DBG("Event notifier notification consumption paused, sleeping...");
+		sleep(1);
+		goto end;
+	}
+
+	ret = handle_notification_thread_event_notification(
+			state, event_source_fd, domain);
+	if (ret) {
+		ERR("[notification-thread] Event notification handling error occurred for fd: %d",
+				event_source_fd);
+		ret = -1;
+		goto end;
+	}
+
+end:
+	return ret;
+}
+
+/*
+ * Return the event source domain type via parameter.
+ */
+static bool fd_is_event_notification_source(const struct notification_thread_state *state,
+		int fd,
+		enum lttng_domain_type *domain)
+{
+	struct notification_event_tracer_event_source_element *source_element;
+
+	assert(domain);
+
+	cds_list_for_each_entry(source_element,
+			&state->tracer_event_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.
@@ -544,6 +635,7 @@ 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");
 
@@ -563,6 +655,10 @@ void *thread_notification(void *data)
 		goto end;
 	}
 
+	if (testpoint(sessiond_thread_notification)) {
+		goto end;
+	}
+
 	while (true) {
 		int fd_count, i;
 
@@ -582,6 +678,12 @@ void *thread_notification(void *data)
 			goto error;
 		}
 
+		/*
+		 * Reset restart_poll flag so that calls below might turn it
+		 * on.
+		 */
+		state.restart_poll = false;
+
 		fd_count = ret;
 		for (i = 0; i < fd_count; i++) {
 			int fd = LTTNG_POLL_GETFD(&state.events, i);
@@ -621,6 +723,11 @@ void *thread_notification(void *data)
 				if (ret) {
 					goto error;
 				}
+			} else if (fd_is_event_notification_source(&state, fd, &domain)) {
+				ret = handle_event_notification_pipe(fd, domain, revents, &state);
+				if (ret) {
+					goto error;
+				}
 			} else {
 				/* Activity on a client's socket. */
 				if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
@@ -654,6 +761,15 @@ void *thread_notification(void *data)
 					}
 				}
 			}
+
+			/*
+			 * Calls above might have changed the state of the
+			 * FDs in `state.events`. Call _poll_wait() again to
+			 * ensure we have a consistent state.
+			 */
+			if (state.restart_poll) {
+				break;
+			}
 		}
 	}
 exit: