+++ /dev/null
-/*
- * Copyright (C) 2018 Jérémie Galarneau <jeremie.galarneau@efficios.com>
- *
- * SPDX-License-Identifier: GPL-2.0-only
- *
- */
-
-#include "thread.h"
-#include <urcu/list.h>
-#include <urcu/ref.h>
-#include <pthread.h>
-#include <common/macros.h>
-#include <common/error.h>
-#include <common/defaults.h>
-
-static struct thread_list {
- struct cds_list_head head;
- pthread_mutex_t lock;
-} thread_list = {
- .head = CDS_LIST_HEAD_INIT(thread_list.head),
- .lock = PTHREAD_MUTEX_INITIALIZER,
-};
-
-struct lttng_thread {
- struct urcu_ref ref;
- struct cds_list_head node;
- pthread_t thread;
- const char *name;
- /* Main thread function */
- lttng_thread_entry_point entry;
- /*
- * Thread-specific shutdown method. Allows threads to implement their
- * own shutdown mechanism as some of them use a structured message
- * passed through a command queue and some rely on a dedicated "quit"
- * pipe.
- */
- lttng_thread_shutdown_cb shutdown;
- lttng_thread_cleanup_cb cleanup;
- /* Thread implementation-specific data. */
- void *data;
-};
-
-static
-void lttng_thread_destroy(struct lttng_thread *thread)
-{
- if (thread->cleanup) {
- thread->cleanup(thread->data);
- }
- free(thread);
-}
-
-static
-void lttng_thread_release(struct urcu_ref *ref)
-{
- lttng_thread_destroy(container_of(ref, struct lttng_thread, ref));
-}
-
-static
-void *launch_thread(void *data)
-{
- void *ret;
- struct lttng_thread *thread = (struct lttng_thread *) data;
-
- logger_set_thread_name(thread->name, true);
- DBG("Entering thread entry point");
- ret = thread->entry(thread->data);
- DBG("Thread entry point has returned");
- return ret;
-}
-
-struct lttng_thread *lttng_thread_create(const char *name,
- lttng_thread_entry_point entry,
- lttng_thread_shutdown_cb shutdown,
- lttng_thread_cleanup_cb cleanup,
- void *thread_data)
-{
- int ret;
- struct lttng_thread *thread;
-
- thread = zmalloc(sizeof(*thread));
- if (!thread) {
- goto error_alloc;
- }
-
- urcu_ref_init(&thread->ref);
- CDS_INIT_LIST_HEAD(&thread->node);
- /*
- * Thread names are assumed to be statically allocated strings.
- * It is unnecessary to copy this attribute.
- */
- thread->name = name;
- thread->entry = entry;
- thread->shutdown = shutdown;
- thread->cleanup = cleanup;
- thread->data = thread_data;
-
- pthread_mutex_lock(&thread_list.lock);
- /*
- * Add the thread at the head of the list to shutdown threads in the
- * opposite order of their creation. A reference is taken for the
- * thread list which will be released on shutdown of the thread.
- */
- cds_list_add(&thread->node, &thread_list.head);
- (void) lttng_thread_get(thread);
-
- ret = pthread_create(&thread->thread, default_pthread_attr(),
- launch_thread, thread);
- if (ret) {
- PERROR("Failed to create \"%s\" thread", thread->name);
- goto error_pthread_create;
- }
-
- pthread_mutex_unlock(&thread_list.lock);
- return thread;
-
-error_pthread_create:
- cds_list_del(&thread->node);
- /* Release list reference. */
- lttng_thread_put(thread);
- pthread_mutex_unlock(&thread_list.lock);
- /* Release initial reference. */
- lttng_thread_put(thread);
-error_alloc:
- return NULL;
-}
-
-bool lttng_thread_get(struct lttng_thread *thread)
-{
- return urcu_ref_get_unless_zero(&thread->ref);
-}
-
-void lttng_thread_put(struct lttng_thread *thread)
-{
- if (!thread) {
- return;
- }
- assert(thread->ref.refcount);
- urcu_ref_put(&thread->ref, lttng_thread_release);
-}
-
-const char *lttng_thread_get_name(const struct lttng_thread *thread)
-{
- return thread->name;
-}
-
-static
-bool _lttng_thread_shutdown(struct lttng_thread *thread)
-{
- int ret;
- void *status;
- bool result = true;
-
- DBG("Shutting down \"%s\" thread", thread->name);
- if (thread->shutdown) {
- result = thread->shutdown(thread->data);
- if (!result) {
- result = false;
- goto end;
- }
- }
-
- ret = pthread_join(thread->thread, &status);
- if (ret) {
- PERROR("Failed to join \"%s\" thread", thread->name);
- result = false;
- goto end;
- }
- DBG("Joined thread \"%s\"", thread->name);
-end:
- return result;
-}
-
-bool lttng_thread_shutdown(struct lttng_thread *thread)
-{
- const bool result = _lttng_thread_shutdown(thread);
-
- if (result) {
- /* Release the list's reference to the thread. */
- pthread_mutex_lock(&thread_list.lock);
- cds_list_del(&thread->node);
- lttng_thread_put(thread);
- pthread_mutex_unlock(&thread_list.lock);
- }
- return result;
-}
-
-void lttng_thread_list_shutdown_orphans(void)
-{
- struct lttng_thread *thread, *tmp;
-
- pthread_mutex_lock(&thread_list.lock);
- cds_list_for_each_entry_safe(thread, tmp, &thread_list.head, node) {
- bool result;
- const long ref = uatomic_read(&thread->ref.refcount);
-
- if (ref != 1) {
- /*
- * Other external references to the thread exist, skip.
- */
- continue;
- }
-
- result = _lttng_thread_shutdown(thread);
- if (!result) {
- ERR("Failed to shutdown thread \"%s\"", thread->name);
- }
- }
- pthread_mutex_unlock(&thread_list.lock);
-}
projects / lttng-tools.git / blobdiff