+/*
+ * Copyright (C) 2007 Mathieu Desnoyers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * LTT marker control module over /proc
+ */
+
+//ust// #include <linux/proc_fs.h>
+//ust// #include <linux/module.h>
+//ust// #include <linux/stat.h>
+//ust// #include <linux/vmalloc.h>
+//ust// #include <linux/marker.h>
+//ust// #include <linux/ltt-tracer.h>
+//ust// #include <linux/uaccess.h>
+//ust// #include <linux/string.h>
+//ust// #include <linux/ctype.h>
+//ust// #include <linux/list.h>
+//ust// #include <linux/mutex.h>
+//ust// #include <linux/seq_file.h>
+//ust// #include <linux/slab.h>
+#include "kernelcompat.h"
+#include "list.h"
+#include "tracer.h"
+#include "usterr.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,
+};
+
+//ust//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);
+
+//ust// static struct proc_dir_entry *pentry;
+
+//ust// static struct file_operations ltt_fops;
+
+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;
+}
+
+static char *skip_spaces(char *buf)
+{
+ while (*buf != '\0' && isspace(*buf))
+ buf++;
+ return buf;
+}
+
+static char *skip_nonspaces(char *buf)
+{
+ while (*buf != '\0' && !isspace(*buf))
+ buf++;
+ return buf;
+}
+
+static void get_marker_string(char *buf, char **start,
+ char **end)
+{
+ *start = skip_spaces(buf);
+ *end = skip_nonspaces(*start);
+ **end = '\0';
+}
+
+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);
+ free(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 = zmalloc(sizeof(struct ltt_active_marker));
+ 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)
+ free(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);
+ free(pdata);
+ }
+end:
+ mutex_unlock(&probes_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ltt_marker_disconnect);
+
+/*
+ * function handling proc entry write.
+ *
+ * connect <channel name> <marker name> [<probe name>]]
+ * disconnect <channel name> <marker name> [<probe name>]
+ */
+//ust// static ssize_t ltt_write(struct file *file, const char __user *buffer,
+//ust// size_t count, loff_t *offset)
+//ust// {
+//ust// char *kbuf;
+//ust// char *iter, *marker_action, *arg[4];
+//ust// ssize_t ret;
+//ust// int i;
+//ust//
+//ust// if (!count)
+//ust// return -EINVAL;
+//ust//
+//ust// kbuf = vmalloc(count + 1);
+//ust// kbuf[count] = '\0'; /* Transform into a string */
+//ust// ret = copy_from_user(kbuf, buffer, count);
+//ust// if (ret) {
+//ust// ret = -EINVAL;
+//ust// goto end;
+//ust// }
+//ust// get_marker_string(kbuf, &marker_action, &iter);
+//ust// if (!marker_action || marker_action == iter) {
+//ust// ret = -EINVAL;
+//ust// goto end;
+//ust// }
+//ust// for (i = 0; i < 4; i++) {
+//ust// arg[i] = NULL;
+//ust// if (iter < kbuf + count) {
+//ust// iter++; /* skip the added '\0' */
+//ust// get_marker_string(iter, &arg[i], &iter);
+//ust// if (arg[i] == iter)
+//ust// arg[i] = NULL;
+//ust// }
+//ust// }
+//ust//
+//ust// if (!arg[0] || !arg[1]) {
+//ust// ret = -EINVAL;
+//ust// goto end;
+//ust// }
+//ust//
+//ust// if (!strcmp(marker_action, "connect")) {
+//ust// ret = ltt_marker_connect(arg[0], arg[1], arg[2]);
+//ust// if (ret)
+//ust// goto end;
+//ust// } else if (!strcmp(marker_action, "disconnect")) {
+//ust// ret = ltt_marker_disconnect(arg[0], arg[1], arg[2]);
+//ust// if (ret)
+//ust// goto end;
+//ust// }
+//ust// ret = count;
+//ust// end:
+//ust// vfree(kbuf);
+//ust// return ret;
+//ust// }
+//ust//
+//ust// static void *s_next(struct seq_file *m, void *p, loff_t *pos)
+//ust// {
+//ust// struct marker_iter *iter = m->private;
+//ust//
+//ust// marker_iter_next(iter);
+//ust// if (!iter->marker) {
+//ust// /*
+//ust// * Setting the iter module to -1UL will make sure
+//ust// * that no module can possibly hold the current marker.
+//ust// */
+//ust// iter->module = (void *)-1UL;
+//ust// return NULL;
+//ust// }
+//ust// return iter->marker;
+//ust// }
+//ust//
+//ust// static void *s_start(struct seq_file *m, loff_t *pos)
+//ust// {
+//ust// struct marker_iter *iter = m->private;
+//ust//
+//ust// if (!*pos)
+//ust// marker_iter_reset(iter);
+//ust// marker_iter_start(iter);
+//ust// if (!iter->marker) {
+//ust// /*
+//ust// * Setting the iter module to -1UL will make sure
+//ust// * that no module can possibly hold the current marker.
+//ust// */
+//ust// iter->module = (void *)-1UL;
+//ust// return NULL;
+//ust// }
+//ust// return iter->marker;
+//ust// }
+//ust//
+//ust// static void s_stop(struct seq_file *m, void *p)
+//ust// {
+//ust// marker_iter_stop(m->private);
+//ust// }
+//ust//
+//ust// static int s_show(struct seq_file *m, void *p)
+//ust// {
+//ust// struct marker_iter *iter = m->private;
+//ust//
+//ust// seq_printf(m, "channel: %s marker: %s format: \"%s\" state: %d "
+//ust// "event_id: %hu call: 0x%p probe %s : 0x%p\n",
+//ust// iter->marker->channel,
+//ust// iter->marker->name, iter->marker->format,
+//ust// _imv_read(iter->marker->state),
+//ust// iter->marker->event_id,
+//ust// iter->marker->call,
+//ust// iter->marker->ptype ? "multi" : "single",
+//ust// iter->marker->ptype ?
+//ust// (void*)iter->marker->multi : (void*)iter->marker->single.func);
+//ust// return 0;
+//ust// }
+//ust//
+//ust// static const struct seq_operations ltt_seq_op = {
+//ust// .start = s_start,
+//ust// .next = s_next,
+//ust// .stop = s_stop,
+//ust// .show = s_show,
+//ust// };
+//ust//
+//ust// static int ltt_open(struct inode *inode, struct file *file)
+//ust// {
+//ust// /*
+//ust// * Iterator kept in m->private.
+//ust// * Restart iteration on all modules between reads because we do not lock
+//ust// * the module mutex between those.
+//ust// */
+//ust// int ret;
+//ust// struct marker_iter *iter;
+//ust//
+//ust// iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+//ust// if (!iter)
+//ust// return -ENOMEM;
+//ust//
+//ust// ret = seq_open(file, <t_seq_op);
+//ust// if (ret == 0)
+//ust// ((struct seq_file *)file->private_data)->private = iter;
+//ust// else
+//ust// kfree(iter);
+//ust// return ret;
+//ust// }
+//ust//
+//ust// static struct file_operations ltt_fops = {
+//ust// .write = ltt_write,
+//ust// .open = ltt_open,
+//ust// .read = seq_read,
+//ust// .llseek = seq_lseek,
+//ust// .release = seq_release_private,
+//ust// };
+
+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);
+ free(pdata);
+ }
+}
+
+static char initialized = 0;
+
+void __attribute__((constructor)) init_marker_control(void)
+{
+ if(!initialized) {
+ int ret;
+
+//ust// pentry = create_proc_entry("ltt", S_IRUSR|S_IWUSR, NULL);
+//ust// if (!pentry)
+//ust// return -EBUSY;
+//ust// 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);
+//ust// pentry->proc_fops = <t_fops;
+
+ initialized = 1;
+ }
+
+ return 0;
+}
+//ust// module_init(marker_control_init);
+
+static void __exit marker_control_exit(void)
+{
+ int ret;
+
+//ust// remove_proc_entry("ltt", NULL);
+ 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();
+//ust// kmem_cache_destroy(markers_loaded_cachep);
+//ust// marker_synchronize_unregister();
+}
+//ust// module_exit(marker_control_exit);
+
+//ust// MODULE_LICENSE("GPL");
+//ust// MODULE_AUTHOR("Mathieu Desnoyers");
+//ust// MODULE_DESCRIPTION("Linux Trace Toolkit Marker Control");
projects / lttng-ust.git / commitdiff
