+++ /dev/null
-/*
- * Copyright (C) 2007 Mathieu Desnoyers
- *
- * Dual LGPL v2.1/GPL v2 license.
- */
-
-#include <linux/module.h>
-#include <linux/stat.h>
-#include <linux/vmalloc.h>
-#include <linux/marker.h>
-#include <linux/uaccess.h>
-#include <linux/string.h>
-#include <linux/ctype.h>
-#include <linux/list.h>
-#include <linux/mutex.h>
-#include <linux/seq_file.h>
-#include <linux/slab.h>
-
-#include "ltt-tracer.h"
-
-#define DEFAULT_CHANNEL "cpu"
-#define DEFAULT_PROBE "default"
-
-LIST_HEAD(probes_list);
-
-/*
- * Mutex protecting the probe slab cache.
- * Nests inside the traces mutex.
- */
-DEFINE_MUTEX(probes_mutex);
-
-struct ltt_available_probe default_probe = {
- .name = "default",
- .format = NULL,
- .probe_func = ltt_vtrace,
- .callbacks[0] = ltt_serialize_data,
-};
-
-static struct kmem_cache *markers_loaded_cachep;
-static LIST_HEAD(markers_loaded_list);
-/*
- * List sorted by name strcmp order.
- */
-static LIST_HEAD(probes_registered_list);
-
-static struct ltt_available_probe *get_probe_from_name(const char *pname)
-{
- struct ltt_available_probe *iter;
- int comparison, found = 0;
-
- if (!pname)
- pname = DEFAULT_PROBE;
- list_for_each_entry(iter, &probes_registered_list, node) {
- comparison = strcmp(pname, iter->name);
- if (!comparison)
- found = 1;
- if (comparison <= 0)
- break;
- }
- if (found)
- return iter;
- else
- return NULL;
-}
-
-int ltt_probe_register(struct ltt_available_probe *pdata)
-{
- int ret = 0;
- int comparison;
- struct ltt_available_probe *iter;
-
- mutex_lock(&probes_mutex);
- list_for_each_entry_reverse(iter, &probes_registered_list, node) {
- comparison = strcmp(pdata->name, iter->name);
- if (!comparison) {
- ret = -EBUSY;
- goto end;
- } else if (comparison > 0) {
- /* We belong to the location right after iter. */
- list_add(&pdata->node, &iter->node);
- goto end;
- }
- }
- /* Should be added at the head of the list */
- list_add(&pdata->node, &probes_registered_list);
-end:
- mutex_unlock(&probes_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_probe_register);
-
-/*
- * Called when a probe does not want to be called anymore.
- */
-int ltt_probe_unregister(struct ltt_available_probe *pdata)
-{
- int ret = 0;
- struct ltt_active_marker *amark, *tmp;
-
- mutex_lock(&probes_mutex);
- list_for_each_entry_safe(amark, tmp, &markers_loaded_list, node) {
- if (amark->probe == pdata) {
- ret = marker_probe_unregister_private_data(
- pdata->probe_func, amark);
- if (ret)
- goto end;
- list_del(&amark->node);
- kmem_cache_free(markers_loaded_cachep, amark);
- }
- }
- list_del(&pdata->node);
-end:
- mutex_unlock(&probes_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_probe_unregister);
-
-/*
- * Connect marker "mname" to probe "pname".
- * Only allow _only_ probe instance to be connected to a marker.
- */
-int ltt_marker_connect(const char *channel, const char *mname,
- const char *pname)
-
-{
- int ret;
- struct ltt_active_marker *pdata;
- struct ltt_available_probe *probe;
-
- ltt_lock_traces();
- mutex_lock(&probes_mutex);
- probe = get_probe_from_name(pname);
- if (!probe) {
- ret = -ENOENT;
- goto end;
- }
- pdata = marker_get_private_data(channel, mname, probe->probe_func, 0);
- if (pdata && !IS_ERR(pdata)) {
- ret = -EEXIST;
- goto end;
- }
- pdata = kmem_cache_zalloc(markers_loaded_cachep, GFP_KERNEL);
- if (!pdata) {
- ret = -ENOMEM;
- goto end;
- }
- pdata->probe = probe;
- /*
- * ID has priority over channel in case of conflict.
- */
- ret = marker_probe_register(channel, mname, NULL,
- probe->probe_func, pdata);
- if (ret)
- kmem_cache_free(markers_loaded_cachep, pdata);
- else
- list_add(&pdata->node, &markers_loaded_list);
-end:
- mutex_unlock(&probes_mutex);
- ltt_unlock_traces();
- return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_marker_connect);
-
-/*
- * Disconnect marker "mname", probe "pname".
- */
-int ltt_marker_disconnect(const char *channel, const char *mname,
- const char *pname)
-{
- struct ltt_active_marker *pdata;
- struct ltt_available_probe *probe;
- int ret = 0;
-
- mutex_lock(&probes_mutex);
- probe = get_probe_from_name(pname);
- if (!probe) {
- ret = -ENOENT;
- goto end;
- }
- pdata = marker_get_private_data(channel, mname, probe->probe_func, 0);
- if (IS_ERR(pdata)) {
- ret = PTR_ERR(pdata);
- goto end;
- } else if (!pdata) {
- /*
- * Not registered by us.
- */
- ret = -EPERM;
- goto end;
- }
- ret = marker_probe_unregister(channel, mname, probe->probe_func, pdata);
- if (ret)
- goto end;
- else {
- list_del(&pdata->node);
- kmem_cache_free(markers_loaded_cachep, pdata);
- }
-end:
- mutex_unlock(&probes_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_marker_disconnect);
-
-static void disconnect_all_markers(void)
-{
- struct ltt_active_marker *pdata, *tmp;
-
- list_for_each_entry_safe(pdata, tmp, &markers_loaded_list, node) {
- marker_probe_unregister_private_data(pdata->probe->probe_func,
- pdata);
- list_del(&pdata->node);
- kmem_cache_free(markers_loaded_cachep, pdata);
- }
-}
-
-static int __init marker_control_init(void)
-{
- int ret;
-
- markers_loaded_cachep = KMEM_CACHE(ltt_active_marker, 0);
-
- ret = ltt_probe_register(&default_probe);
- BUG_ON(ret);
- ret = ltt_marker_connect("metadata", "core_marker_format",
- DEFAULT_PROBE);
- BUG_ON(ret);
- ret = ltt_marker_connect("metadata", "core_marker_id", DEFAULT_PROBE);
- BUG_ON(ret);
-
- return 0;
-}
-module_init(marker_control_init);
-
-static void __exit marker_control_exit(void)
-{
- int ret;
-
- ret = ltt_marker_disconnect("metadata", "core_marker_format",
- DEFAULT_PROBE);
- BUG_ON(ret);
- ret = ltt_marker_disconnect("metadata", "core_marker_id",
- DEFAULT_PROBE);
- BUG_ON(ret);
- ret = ltt_probe_unregister(&default_probe);
- BUG_ON(ret);
- disconnect_all_markers();
- kmem_cache_destroy(markers_loaded_cachep);
- marker_synchronize_unregister();
-}
-module_exit(marker_control_exit);
-
-MODULE_LICENSE("GPL and additional rights");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Linux Trace Toolkit Marker Control");
projects / lttng-modules.git / blobdiff