+++ /dev/null
-/*
- * lttng-probes.c
- *
- * Holds LTTng probes registry.
- *
- * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@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 as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * 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 <linux/module.h>
-#include <linux/list.h>
-#include <linux/mutex.h>
-#include <linux/seq_file.h>
-
-#include "lttng-events.h"
-
-static LIST_HEAD(probe_list);
-static DEFINE_MUTEX(probe_mutex);
-
-static
-const struct lttng_event_desc *find_event(const char *name)
-{
- struct lttng_probe_desc *probe_desc;
- int i;
-
- list_for_each_entry(probe_desc, &probe_list, head) {
- for (i = 0; i < probe_desc->nr_events; i++) {
- if (!strcmp(probe_desc->event_desc[i]->name, name))
- return probe_desc->event_desc[i];
- }
- }
- return NULL;
-}
-
-int lttng_probe_register(struct lttng_probe_desc *desc)
-{
- int ret = 0;
- int i;
-
- mutex_lock(&probe_mutex);
- /*
- * TODO: This is O(N^2). Turn into a hash table when probe registration
- * overhead becomes an issue.
- */
- for (i = 0; i < desc->nr_events; i++) {
- if (find_event(desc->event_desc[i]->name)) {
- ret = -EEXIST;
- goto end;
- }
- }
- list_add(&desc->head, &probe_list);
-end:
- mutex_unlock(&probe_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(lttng_probe_register);
-
-void lttng_probe_unregister(struct lttng_probe_desc *desc)
-{
- mutex_lock(&probe_mutex);
- list_del(&desc->head);
- mutex_unlock(&probe_mutex);
-}
-EXPORT_SYMBOL_GPL(lttng_probe_unregister);
-
-const struct lttng_event_desc *lttng_event_get(const char *name)
-{
- const struct lttng_event_desc *event;
- int ret;
-
- mutex_lock(&probe_mutex);
- event = find_event(name);
- mutex_unlock(&probe_mutex);
- if (!event)
- return NULL;
- ret = try_module_get(event->owner);
- WARN_ON_ONCE(!ret);
- return event;
-}
-EXPORT_SYMBOL_GPL(lttng_event_get);
-
-void lttng_event_put(const struct lttng_event_desc *event)
-{
- module_put(event->owner);
-}
-EXPORT_SYMBOL_GPL(lttng_event_put);
-
-static
-void *tp_list_start(struct seq_file *m, loff_t *pos)
-{
- struct lttng_probe_desc *probe_desc;
- int iter = 0, i;
-
- mutex_lock(&probe_mutex);
- list_for_each_entry(probe_desc, &probe_list, head) {
- for (i = 0; i < probe_desc->nr_events; i++) {
- if (iter++ >= *pos)
- return (void *) probe_desc->event_desc[i];
- }
- }
- /* End of list */
- return NULL;
-}
-
-static
-void *tp_list_next(struct seq_file *m, void *p, loff_t *ppos)
-{
- struct lttng_probe_desc *probe_desc;
- int iter = 0, i;
-
- (*ppos)++;
- list_for_each_entry(probe_desc, &probe_list, head) {
- for (i = 0; i < probe_desc->nr_events; i++) {
- if (iter++ >= *ppos)
- return (void *) probe_desc->event_desc[i];
- }
- }
- /* End of list */
- return NULL;
-}
-
-static
-void tp_list_stop(struct seq_file *m, void *p)
-{
- mutex_unlock(&probe_mutex);
-}
-
-static
-int tp_list_show(struct seq_file *m, void *p)
-{
- const struct lttng_event_desc *probe_desc = p;
-
- /*
- * Don't export lttng internal event: lttng_metadata.
- */
- if (!strcmp(probe_desc->name, "lttng_metadata"))
- return 0;
- seq_printf(m, "event { name = %s; };\n",
- probe_desc->name);
- return 0;
-}
-
-static
-const struct seq_operations lttng_tracepoint_list_seq_ops = {
- .start = tp_list_start,
- .next = tp_list_next,
- .stop = tp_list_stop,
- .show = tp_list_show,
-};
-
-static
-int lttng_tracepoint_list_open(struct inode *inode, struct file *file)
-{
- return seq_open(file, <tng_tracepoint_list_seq_ops);
-}
-
-const struct file_operations lttng_tracepoint_list_fops = {
- .owner = THIS_MODULE,
- .open = lttng_tracepoint_list_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = seq_release,
-};