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1668 lines
41 KiB
1668 lines
41 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
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* trace_events_trigger - trace event triggers |
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* |
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* Copyright (C) 2013 Tom Zanussi <[email protected]> |
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*/ |
|
|
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#include <linux/security.h> |
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#include <linux/module.h> |
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#include <linux/ctype.h> |
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#include <linux/mutex.h> |
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#include <linux/slab.h> |
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#include <linux/rculist.h> |
|
|
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#include "trace.h" |
|
|
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static LIST_HEAD(trigger_commands); |
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static DEFINE_MUTEX(trigger_cmd_mutex); |
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|
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void trigger_data_free(struct event_trigger_data *data) |
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{ |
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if (data->cmd_ops->set_filter) |
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data->cmd_ops->set_filter(NULL, data, NULL); |
|
|
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/* make sure current triggers exit before free */ |
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tracepoint_synchronize_unregister(); |
|
|
|
kfree(data); |
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} |
|
|
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/** |
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* event_triggers_call - Call triggers associated with a trace event |
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* @file: The trace_event_file associated with the event |
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* @rec: The trace entry for the event, NULL for unconditional invocation |
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* |
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* For each trigger associated with an event, invoke the trigger |
|
* function registered with the associated trigger command. If rec is |
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* non-NULL, it means that the trigger requires further processing and |
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* shouldn't be unconditionally invoked. If rec is non-NULL and the |
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* trigger has a filter associated with it, rec will checked against |
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* the filter and if the record matches the trigger will be invoked. |
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* If the trigger is a 'post_trigger', meaning it shouldn't be invoked |
|
* in any case until the current event is written, the trigger |
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* function isn't invoked but the bit associated with the deferred |
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* trigger is set in the return value. |
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* |
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* Returns an enum event_trigger_type value containing a set bit for |
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* any trigger that should be deferred, ETT_NONE if nothing to defer. |
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* |
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* Called from tracepoint handlers (with rcu_read_lock_sched() held). |
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* |
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* Return: an enum event_trigger_type value containing a set bit for |
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* any trigger that should be deferred, ETT_NONE if nothing to defer. |
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*/ |
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enum event_trigger_type |
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event_triggers_call(struct trace_event_file *file, void *rec, |
|
struct ring_buffer_event *event) |
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{ |
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struct event_trigger_data *data; |
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enum event_trigger_type tt = ETT_NONE; |
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struct event_filter *filter; |
|
|
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if (list_empty(&file->triggers)) |
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return tt; |
|
|
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list_for_each_entry_rcu(data, &file->triggers, list) { |
|
if (data->paused) |
|
continue; |
|
if (!rec) { |
|
data->ops->func(data, rec, event); |
|
continue; |
|
} |
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filter = rcu_dereference_sched(data->filter); |
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if (filter && !filter_match_preds(filter, rec)) |
|
continue; |
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if (event_command_post_trigger(data->cmd_ops)) { |
|
tt |= data->cmd_ops->trigger_type; |
|
continue; |
|
} |
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data->ops->func(data, rec, event); |
|
} |
|
return tt; |
|
} |
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EXPORT_SYMBOL_GPL(event_triggers_call); |
|
|
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/** |
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* event_triggers_post_call - Call 'post_triggers' for a trace event |
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* @file: The trace_event_file associated with the event |
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* @tt: enum event_trigger_type containing a set bit for each trigger to invoke |
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* |
|
* For each trigger associated with an event, invoke the trigger |
|
* function registered with the associated trigger command, if the |
|
* corresponding bit is set in the tt enum passed into this function. |
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* See @event_triggers_call for details on how those bits are set. |
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* |
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* Called from tracepoint handlers (with rcu_read_lock_sched() held). |
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*/ |
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void |
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event_triggers_post_call(struct trace_event_file *file, |
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enum event_trigger_type tt) |
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{ |
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struct event_trigger_data *data; |
|
|
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list_for_each_entry_rcu(data, &file->triggers, list) { |
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if (data->paused) |
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continue; |
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if (data->cmd_ops->trigger_type & tt) |
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data->ops->func(data, NULL, NULL); |
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} |
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} |
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EXPORT_SYMBOL_GPL(event_triggers_post_call); |
|
|
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#define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) |
|
|
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static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
|
{ |
|
struct trace_event_file *event_file = event_file_data(m->private); |
|
|
|
if (t == SHOW_AVAILABLE_TRIGGERS) { |
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(*pos)++; |
|
return NULL; |
|
} |
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return seq_list_next(t, &event_file->triggers, pos); |
|
} |
|
|
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static void *trigger_start(struct seq_file *m, loff_t *pos) |
|
{ |
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struct trace_event_file *event_file; |
|
|
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/* ->stop() is called even if ->start() fails */ |
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mutex_lock(&event_mutex); |
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event_file = event_file_data(m->private); |
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if (unlikely(!event_file)) |
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return ERR_PTR(-ENODEV); |
|
|
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if (list_empty(&event_file->triggers)) |
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return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; |
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|
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return seq_list_start(&event_file->triggers, *pos); |
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} |
|
|
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static void trigger_stop(struct seq_file *m, void *t) |
|
{ |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
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static int trigger_show(struct seq_file *m, void *v) |
|
{ |
|
struct event_trigger_data *data; |
|
struct event_command *p; |
|
|
|
if (v == SHOW_AVAILABLE_TRIGGERS) { |
|
seq_puts(m, "# Available triggers:\n"); |
|
seq_putc(m, '#'); |
|
mutex_lock(&trigger_cmd_mutex); |
|
list_for_each_entry_reverse(p, &trigger_commands, list) |
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seq_printf(m, " %s", p->name); |
|
seq_putc(m, '\n'); |
|
mutex_unlock(&trigger_cmd_mutex); |
|
return 0; |
|
} |
|
|
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data = list_entry(v, struct event_trigger_data, list); |
|
data->ops->print(m, data->ops, data); |
|
|
|
return 0; |
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} |
|
|
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static const struct seq_operations event_triggers_seq_ops = { |
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.start = trigger_start, |
|
.next = trigger_next, |
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.stop = trigger_stop, |
|
.show = trigger_show, |
|
}; |
|
|
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static int event_trigger_regex_open(struct inode *inode, struct file *file) |
|
{ |
|
int ret; |
|
|
|
ret = security_locked_down(LOCKDOWN_TRACEFS); |
|
if (ret) |
|
return ret; |
|
|
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mutex_lock(&event_mutex); |
|
|
|
if (unlikely(!event_file_data(file))) { |
|
mutex_unlock(&event_mutex); |
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return -ENODEV; |
|
} |
|
|
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if ((file->f_mode & FMODE_WRITE) && |
|
(file->f_flags & O_TRUNC)) { |
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struct trace_event_file *event_file; |
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struct event_command *p; |
|
|
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event_file = event_file_data(file); |
|
|
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list_for_each_entry(p, &trigger_commands, list) { |
|
if (p->unreg_all) |
|
p->unreg_all(event_file); |
|
} |
|
} |
|
|
|
if (file->f_mode & FMODE_READ) { |
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ret = seq_open(file, &event_triggers_seq_ops); |
|
if (!ret) { |
|
struct seq_file *m = file->private_data; |
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m->private = file; |
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} |
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} |
|
|
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mutex_unlock(&event_mutex); |
|
|
|
return ret; |
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} |
|
|
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int trigger_process_regex(struct trace_event_file *file, char *buff) |
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{ |
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char *command, *next; |
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struct event_command *p; |
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int ret = -EINVAL; |
|
|
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next = buff = skip_spaces(buff); |
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command = strsep(&next, ": \t"); |
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if (next) { |
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next = skip_spaces(next); |
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if (!*next) |
|
next = NULL; |
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} |
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command = (command[0] != '!') ? command : command + 1; |
|
|
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mutex_lock(&trigger_cmd_mutex); |
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list_for_each_entry(p, &trigger_commands, list) { |
|
if (strcmp(p->name, command) == 0) { |
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ret = p->func(p, file, buff, command, next); |
|
goto out_unlock; |
|
} |
|
} |
|
out_unlock: |
|
mutex_unlock(&trigger_cmd_mutex); |
|
|
|
return ret; |
|
} |
|
|
|
static ssize_t event_trigger_regex_write(struct file *file, |
|
const char __user *ubuf, |
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size_t cnt, loff_t *ppos) |
|
{ |
|
struct trace_event_file *event_file; |
|
ssize_t ret; |
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char *buf; |
|
|
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if (!cnt) |
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return 0; |
|
|
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if (cnt >= PAGE_SIZE) |
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return -EINVAL; |
|
|
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buf = memdup_user_nul(ubuf, cnt); |
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if (IS_ERR(buf)) |
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return PTR_ERR(buf); |
|
|
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strim(buf); |
|
|
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mutex_lock(&event_mutex); |
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event_file = event_file_data(file); |
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if (unlikely(!event_file)) { |
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mutex_unlock(&event_mutex); |
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kfree(buf); |
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return -ENODEV; |
|
} |
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ret = trigger_process_regex(event_file, buf); |
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mutex_unlock(&event_mutex); |
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|
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kfree(buf); |
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if (ret < 0) |
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goto out; |
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|
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*ppos += cnt; |
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ret = cnt; |
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out: |
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return ret; |
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} |
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|
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static int event_trigger_regex_release(struct inode *inode, struct file *file) |
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{ |
|
mutex_lock(&event_mutex); |
|
|
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if (file->f_mode & FMODE_READ) |
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seq_release(inode, file); |
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|
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mutex_unlock(&event_mutex); |
|
|
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return 0; |
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} |
|
|
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static ssize_t |
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event_trigger_write(struct file *filp, const char __user *ubuf, |
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size_t cnt, loff_t *ppos) |
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{ |
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return event_trigger_regex_write(filp, ubuf, cnt, ppos); |
|
} |
|
|
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static int |
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event_trigger_open(struct inode *inode, struct file *filp) |
|
{ |
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/* Checks for tracefs lockdown */ |
|
return event_trigger_regex_open(inode, filp); |
|
} |
|
|
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static int |
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event_trigger_release(struct inode *inode, struct file *file) |
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{ |
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return event_trigger_regex_release(inode, file); |
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} |
|
|
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const struct file_operations event_trigger_fops = { |
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.open = event_trigger_open, |
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.read = seq_read, |
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.write = event_trigger_write, |
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.llseek = tracing_lseek, |
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.release = event_trigger_release, |
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}; |
|
|
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/* |
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* Currently we only register event commands from __init, so mark this |
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* __init too. |
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*/ |
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__init int register_event_command(struct event_command *cmd) |
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{ |
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struct event_command *p; |
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int ret = 0; |
|
|
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mutex_lock(&trigger_cmd_mutex); |
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list_for_each_entry(p, &trigger_commands, list) { |
|
if (strcmp(cmd->name, p->name) == 0) { |
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ret = -EBUSY; |
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goto out_unlock; |
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} |
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} |
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list_add(&cmd->list, &trigger_commands); |
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out_unlock: |
|
mutex_unlock(&trigger_cmd_mutex); |
|
|
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return ret; |
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} |
|
|
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/* |
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* Currently we only unregister event commands from __init, so mark |
|
* this __init too. |
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*/ |
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__init int unregister_event_command(struct event_command *cmd) |
|
{ |
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struct event_command *p, *n; |
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int ret = -ENODEV; |
|
|
|
mutex_lock(&trigger_cmd_mutex); |
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list_for_each_entry_safe(p, n, &trigger_commands, list) { |
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if (strcmp(cmd->name, p->name) == 0) { |
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ret = 0; |
|
list_del_init(&p->list); |
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goto out_unlock; |
|
} |
|
} |
|
out_unlock: |
|
mutex_unlock(&trigger_cmd_mutex); |
|
|
|
return ret; |
|
} |
|
|
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/** |
|
* event_trigger_print - Generic event_trigger_ops @print implementation |
|
* @name: The name of the event trigger |
|
* @m: The seq_file being printed to |
|
* @data: Trigger-specific data |
|
* @filter_str: filter_str to print, if present |
|
* |
|
* Common implementation for event triggers to print themselves. |
|
* |
|
* Usually wrapped by a function that simply sets the @name of the |
|
* trigger command and then invokes this. |
|
* |
|
* Return: 0 on success, errno otherwise |
|
*/ |
|
static int |
|
event_trigger_print(const char *name, struct seq_file *m, |
|
void *data, char *filter_str) |
|
{ |
|
long count = (long)data; |
|
|
|
seq_puts(m, name); |
|
|
|
if (count == -1) |
|
seq_puts(m, ":unlimited"); |
|
else |
|
seq_printf(m, ":count=%ld", count); |
|
|
|
if (filter_str) |
|
seq_printf(m, " if %s\n", filter_str); |
|
else |
|
seq_putc(m, '\n'); |
|
|
|
return 0; |
|
} |
|
|
|
/** |
|
* event_trigger_init - Generic event_trigger_ops @init implementation |
|
* @ops: The trigger ops associated with the trigger |
|
* @data: Trigger-specific data |
|
* |
|
* Common implementation of event trigger initialization. |
|
* |
|
* Usually used directly as the @init method in event trigger |
|
* implementations. |
|
* |
|
* Return: 0 on success, errno otherwise |
|
*/ |
|
int event_trigger_init(struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
data->ref++; |
|
return 0; |
|
} |
|
|
|
/** |
|
* event_trigger_free - Generic event_trigger_ops @free implementation |
|
* @ops: The trigger ops associated with the trigger |
|
* @data: Trigger-specific data |
|
* |
|
* Common implementation of event trigger de-initialization. |
|
* |
|
* Usually used directly as the @free method in event trigger |
|
* implementations. |
|
*/ |
|
static void |
|
event_trigger_free(struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
if (WARN_ON_ONCE(data->ref <= 0)) |
|
return; |
|
|
|
data->ref--; |
|
if (!data->ref) |
|
trigger_data_free(data); |
|
} |
|
|
|
int trace_event_trigger_enable_disable(struct trace_event_file *file, |
|
int trigger_enable) |
|
{ |
|
int ret = 0; |
|
|
|
if (trigger_enable) { |
|
if (atomic_inc_return(&file->tm_ref) > 1) |
|
return ret; |
|
set_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
|
ret = trace_event_enable_disable(file, 1, 1); |
|
} else { |
|
if (atomic_dec_return(&file->tm_ref) > 0) |
|
return ret; |
|
clear_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
|
ret = trace_event_enable_disable(file, 0, 1); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
/** |
|
* clear_event_triggers - Clear all triggers associated with a trace array |
|
* @tr: The trace array to clear |
|
* |
|
* For each trigger, the triggering event has its tm_ref decremented |
|
* via trace_event_trigger_enable_disable(), and any associated event |
|
* (in the case of enable/disable_event triggers) will have its sm_ref |
|
* decremented via free()->trace_event_enable_disable(). That |
|
* combination effectively reverses the soft-mode/trigger state added |
|
* by trigger registration. |
|
* |
|
* Must be called with event_mutex held. |
|
*/ |
|
void |
|
clear_event_triggers(struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file; |
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
struct event_trigger_data *data, *n; |
|
list_for_each_entry_safe(data, n, &file->triggers, list) { |
|
trace_event_trigger_enable_disable(file, 0); |
|
list_del_rcu(&data->list); |
|
if (data->ops->free) |
|
data->ops->free(data->ops, data); |
|
} |
|
} |
|
} |
|
|
|
/** |
|
* update_cond_flag - Set or reset the TRIGGER_COND bit |
|
* @file: The trace_event_file associated with the event |
|
* |
|
* If an event has triggers and any of those triggers has a filter or |
|
* a post_trigger, trigger invocation needs to be deferred until after |
|
* the current event has logged its data, and the event should have |
|
* its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be |
|
* cleared. |
|
*/ |
|
void update_cond_flag(struct trace_event_file *file) |
|
{ |
|
struct event_trigger_data *data; |
|
bool set_cond = false; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
list_for_each_entry(data, &file->triggers, list) { |
|
if (data->filter || event_command_post_trigger(data->cmd_ops) || |
|
event_command_needs_rec(data->cmd_ops)) { |
|
set_cond = true; |
|
break; |
|
} |
|
} |
|
|
|
if (set_cond) |
|
set_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
|
else |
|
clear_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
|
} |
|
|
|
/** |
|
* register_trigger - Generic event_command @reg implementation |
|
* @glob: The raw string used to register the trigger |
|
* @ops: The trigger ops associated with the trigger |
|
* @data: Trigger-specific data to associate with the trigger |
|
* @file: The trace_event_file associated with the event |
|
* |
|
* Common implementation for event trigger registration. |
|
* |
|
* Usually used directly as the @reg method in event command |
|
* implementations. |
|
* |
|
* Return: 0 on success, errno otherwise |
|
*/ |
|
static int register_trigger(char *glob, struct event_trigger_ops *ops, |
|
struct event_trigger_data *data, |
|
struct trace_event_file *file) |
|
{ |
|
struct event_trigger_data *test; |
|
int ret = 0; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
list_for_each_entry(test, &file->triggers, list) { |
|
if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { |
|
ret = -EEXIST; |
|
goto out; |
|
} |
|
} |
|
|
|
if (data->ops->init) { |
|
ret = data->ops->init(data->ops, data); |
|
if (ret < 0) |
|
goto out; |
|
} |
|
|
|
list_add_rcu(&data->list, &file->triggers); |
|
ret++; |
|
|
|
update_cond_flag(file); |
|
if (trace_event_trigger_enable_disable(file, 1) < 0) { |
|
list_del_rcu(&data->list); |
|
update_cond_flag(file); |
|
ret--; |
|
} |
|
out: |
|
return ret; |
|
} |
|
|
|
/** |
|
* unregister_trigger - Generic event_command @unreg implementation |
|
* @glob: The raw string used to register the trigger |
|
* @ops: The trigger ops associated with the trigger |
|
* @test: Trigger-specific data used to find the trigger to remove |
|
* @file: The trace_event_file associated with the event |
|
* |
|
* Common implementation for event trigger unregistration. |
|
* |
|
* Usually used directly as the @unreg method in event command |
|
* implementations. |
|
*/ |
|
static void unregister_trigger(char *glob, struct event_trigger_ops *ops, |
|
struct event_trigger_data *test, |
|
struct trace_event_file *file) |
|
{ |
|
struct event_trigger_data *data; |
|
bool unregistered = false; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
list_for_each_entry(data, &file->triggers, list) { |
|
if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { |
|
unregistered = true; |
|
list_del_rcu(&data->list); |
|
trace_event_trigger_enable_disable(file, 0); |
|
update_cond_flag(file); |
|
break; |
|
} |
|
} |
|
|
|
if (unregistered && data->ops->free) |
|
data->ops->free(data->ops, data); |
|
} |
|
|
|
/** |
|
* event_trigger_callback - Generic event_command @func implementation |
|
* @cmd_ops: The command ops, used for trigger registration |
|
* @file: The trace_event_file associated with the event |
|
* @glob: The raw string used to register the trigger |
|
* @cmd: The cmd portion of the string used to register the trigger |
|
* @param: The params portion of the string used to register the trigger |
|
* |
|
* Common implementation for event command parsing and trigger |
|
* instantiation. |
|
* |
|
* Usually used directly as the @func method in event command |
|
* implementations. |
|
* |
|
* Return: 0 on success, errno otherwise |
|
*/ |
|
static int |
|
event_trigger_callback(struct event_command *cmd_ops, |
|
struct trace_event_file *file, |
|
char *glob, char *cmd, char *param) |
|
{ |
|
struct event_trigger_data *trigger_data; |
|
struct event_trigger_ops *trigger_ops; |
|
char *trigger = NULL; |
|
char *number; |
|
int ret; |
|
|
|
/* separate the trigger from the filter (t:n [if filter]) */ |
|
if (param && isdigit(param[0])) { |
|
trigger = strsep(¶m, " \t"); |
|
if (param) { |
|
param = skip_spaces(param); |
|
if (!*param) |
|
param = NULL; |
|
} |
|
} |
|
|
|
trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); |
|
|
|
ret = -ENOMEM; |
|
trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); |
|
if (!trigger_data) |
|
goto out; |
|
|
|
trigger_data->count = -1; |
|
trigger_data->ops = trigger_ops; |
|
trigger_data->cmd_ops = cmd_ops; |
|
trigger_data->private_data = file; |
|
INIT_LIST_HEAD(&trigger_data->list); |
|
INIT_LIST_HEAD(&trigger_data->named_list); |
|
|
|
if (glob[0] == '!') { |
|
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); |
|
kfree(trigger_data); |
|
ret = 0; |
|
goto out; |
|
} |
|
|
|
if (trigger) { |
|
number = strsep(&trigger, ":"); |
|
|
|
ret = -EINVAL; |
|
if (!strlen(number)) |
|
goto out_free; |
|
|
|
/* |
|
* We use the callback data field (which is a pointer) |
|
* as our counter. |
|
*/ |
|
ret = kstrtoul(number, 0, &trigger_data->count); |
|
if (ret) |
|
goto out_free; |
|
} |
|
|
|
if (!param) /* if param is non-empty, it's supposed to be a filter */ |
|
goto out_reg; |
|
|
|
if (!cmd_ops->set_filter) |
|
goto out_reg; |
|
|
|
ret = cmd_ops->set_filter(param, trigger_data, file); |
|
if (ret < 0) |
|
goto out_free; |
|
|
|
out_reg: |
|
/* Up the trigger_data count to make sure reg doesn't free it on failure */ |
|
event_trigger_init(trigger_ops, trigger_data); |
|
ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); |
|
/* |
|
* The above returns on success the # of functions enabled, |
|
* but if it didn't find any functions it returns zero. |
|
* Consider no functions a failure too. |
|
*/ |
|
if (!ret) { |
|
cmd_ops->unreg(glob, trigger_ops, trigger_data, file); |
|
ret = -ENOENT; |
|
} else if (ret > 0) |
|
ret = 0; |
|
|
|
/* Down the counter of trigger_data or free it if not used anymore */ |
|
event_trigger_free(trigger_ops, trigger_data); |
|
out: |
|
return ret; |
|
|
|
out_free: |
|
if (cmd_ops->set_filter) |
|
cmd_ops->set_filter(NULL, trigger_data, NULL); |
|
kfree(trigger_data); |
|
goto out; |
|
} |
|
|
|
/** |
|
* set_trigger_filter - Generic event_command @set_filter implementation |
|
* @filter_str: The filter string for the trigger, NULL to remove filter |
|
* @trigger_data: Trigger-specific data |
|
* @file: The trace_event_file associated with the event |
|
* |
|
* Common implementation for event command filter parsing and filter |
|
* instantiation. |
|
* |
|
* Usually used directly as the @set_filter method in event command |
|
* implementations. |
|
* |
|
* Also used to remove a filter (if filter_str = NULL). |
|
* |
|
* Return: 0 on success, errno otherwise |
|
*/ |
|
int set_trigger_filter(char *filter_str, |
|
struct event_trigger_data *trigger_data, |
|
struct trace_event_file *file) |
|
{ |
|
struct event_trigger_data *data = trigger_data; |
|
struct event_filter *filter = NULL, *tmp; |
|
int ret = -EINVAL; |
|
char *s; |
|
|
|
if (!filter_str) /* clear the current filter */ |
|
goto assign; |
|
|
|
s = strsep(&filter_str, " \t"); |
|
|
|
if (!strlen(s) || strcmp(s, "if") != 0) |
|
goto out; |
|
|
|
if (!filter_str) |
|
goto out; |
|
|
|
/* The filter is for the 'trigger' event, not the triggered event */ |
|
ret = create_event_filter(file->tr, file->event_call, |
|
filter_str, false, &filter); |
|
/* |
|
* If create_event_filter() fails, filter still needs to be freed. |
|
* Which the calling code will do with data->filter. |
|
*/ |
|
assign: |
|
tmp = rcu_access_pointer(data->filter); |
|
|
|
rcu_assign_pointer(data->filter, filter); |
|
|
|
if (tmp) { |
|
/* Make sure the call is done with the filter */ |
|
tracepoint_synchronize_unregister(); |
|
free_event_filter(tmp); |
|
} |
|
|
|
kfree(data->filter_str); |
|
data->filter_str = NULL; |
|
|
|
if (filter_str) { |
|
data->filter_str = kstrdup(filter_str, GFP_KERNEL); |
|
if (!data->filter_str) { |
|
free_event_filter(rcu_access_pointer(data->filter)); |
|
data->filter = NULL; |
|
ret = -ENOMEM; |
|
} |
|
} |
|
out: |
|
return ret; |
|
} |
|
|
|
static LIST_HEAD(named_triggers); |
|
|
|
/** |
|
* find_named_trigger - Find the common named trigger associated with @name |
|
* @name: The name of the set of named triggers to find the common data for |
|
* |
|
* Named triggers are sets of triggers that share a common set of |
|
* trigger data. The first named trigger registered with a given name |
|
* owns the common trigger data that the others subsequently |
|
* registered with the same name will reference. This function |
|
* returns the common trigger data associated with that first |
|
* registered instance. |
|
* |
|
* Return: the common trigger data for the given named trigger on |
|
* success, NULL otherwise. |
|
*/ |
|
struct event_trigger_data *find_named_trigger(const char *name) |
|
{ |
|
struct event_trigger_data *data; |
|
|
|
if (!name) |
|
return NULL; |
|
|
|
list_for_each_entry(data, &named_triggers, named_list) { |
|
if (data->named_data) |
|
continue; |
|
if (strcmp(data->name, name) == 0) |
|
return data; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
/** |
|
* is_named_trigger - determine if a given trigger is a named trigger |
|
* @test: The trigger data to test |
|
* |
|
* Return: true if 'test' is a named trigger, false otherwise. |
|
*/ |
|
bool is_named_trigger(struct event_trigger_data *test) |
|
{ |
|
struct event_trigger_data *data; |
|
|
|
list_for_each_entry(data, &named_triggers, named_list) { |
|
if (test == data) |
|
return true; |
|
} |
|
|
|
return false; |
|
} |
|
|
|
/** |
|
* save_named_trigger - save the trigger in the named trigger list |
|
* @name: The name of the named trigger set |
|
* @data: The trigger data to save |
|
* |
|
* Return: 0 if successful, negative error otherwise. |
|
*/ |
|
int save_named_trigger(const char *name, struct event_trigger_data *data) |
|
{ |
|
data->name = kstrdup(name, GFP_KERNEL); |
|
if (!data->name) |
|
return -ENOMEM; |
|
|
|
list_add(&data->named_list, &named_triggers); |
|
|
|
return 0; |
|
} |
|
|
|
/** |
|
* del_named_trigger - delete a trigger from the named trigger list |
|
* @data: The trigger data to delete |
|
*/ |
|
void del_named_trigger(struct event_trigger_data *data) |
|
{ |
|
kfree(data->name); |
|
data->name = NULL; |
|
|
|
list_del(&data->named_list); |
|
} |
|
|
|
static void __pause_named_trigger(struct event_trigger_data *data, bool pause) |
|
{ |
|
struct event_trigger_data *test; |
|
|
|
list_for_each_entry(test, &named_triggers, named_list) { |
|
if (strcmp(test->name, data->name) == 0) { |
|
if (pause) { |
|
test->paused_tmp = test->paused; |
|
test->paused = true; |
|
} else { |
|
test->paused = test->paused_tmp; |
|
} |
|
} |
|
} |
|
} |
|
|
|
/** |
|
* pause_named_trigger - Pause all named triggers with the same name |
|
* @data: The trigger data of a named trigger to pause |
|
* |
|
* Pauses a named trigger along with all other triggers having the |
|
* same name. Because named triggers share a common set of data, |
|
* pausing only one is meaningless, so pausing one named trigger needs |
|
* to pause all triggers with the same name. |
|
*/ |
|
void pause_named_trigger(struct event_trigger_data *data) |
|
{ |
|
__pause_named_trigger(data, true); |
|
} |
|
|
|
/** |
|
* unpause_named_trigger - Un-pause all named triggers with the same name |
|
* @data: The trigger data of a named trigger to unpause |
|
* |
|
* Un-pauses a named trigger along with all other triggers having the |
|
* same name. Because named triggers share a common set of data, |
|
* unpausing only one is meaningless, so unpausing one named trigger |
|
* needs to unpause all triggers with the same name. |
|
*/ |
|
void unpause_named_trigger(struct event_trigger_data *data) |
|
{ |
|
__pause_named_trigger(data, false); |
|
} |
|
|
|
/** |
|
* set_named_trigger_data - Associate common named trigger data |
|
* @data: The trigger data of a named trigger to unpause |
|
* |
|
* Named triggers are sets of triggers that share a common set of |
|
* trigger data. The first named trigger registered with a given name |
|
* owns the common trigger data that the others subsequently |
|
* registered with the same name will reference. This function |
|
* associates the common trigger data from the first trigger with the |
|
* given trigger. |
|
*/ |
|
void set_named_trigger_data(struct event_trigger_data *data, |
|
struct event_trigger_data *named_data) |
|
{ |
|
data->named_data = named_data; |
|
} |
|
|
|
struct event_trigger_data * |
|
get_named_trigger_data(struct event_trigger_data *data) |
|
{ |
|
return data->named_data; |
|
} |
|
|
|
static void |
|
traceon_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
if (tracing_is_on()) |
|
return; |
|
|
|
tracing_on(); |
|
} |
|
|
|
static void |
|
traceon_count_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
if (tracing_is_on()) |
|
return; |
|
|
|
if (!data->count) |
|
return; |
|
|
|
if (data->count != -1) |
|
(data->count)--; |
|
|
|
tracing_on(); |
|
} |
|
|
|
static void |
|
traceoff_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
if (!tracing_is_on()) |
|
return; |
|
|
|
tracing_off(); |
|
} |
|
|
|
static void |
|
traceoff_count_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
if (!tracing_is_on()) |
|
return; |
|
|
|
if (!data->count) |
|
return; |
|
|
|
if (data->count != -1) |
|
(data->count)--; |
|
|
|
tracing_off(); |
|
} |
|
|
|
static int |
|
traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
return event_trigger_print("traceon", m, (void *)data->count, |
|
data->filter_str); |
|
} |
|
|
|
static int |
|
traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
return event_trigger_print("traceoff", m, (void *)data->count, |
|
data->filter_str); |
|
} |
|
|
|
static struct event_trigger_ops traceon_trigger_ops = { |
|
.func = traceon_trigger, |
|
.print = traceon_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops traceon_count_trigger_ops = { |
|
.func = traceon_count_trigger, |
|
.print = traceon_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops traceoff_trigger_ops = { |
|
.func = traceoff_trigger, |
|
.print = traceoff_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops traceoff_count_trigger_ops = { |
|
.func = traceoff_count_trigger, |
|
.print = traceoff_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops * |
|
onoff_get_trigger_ops(char *cmd, char *param) |
|
{ |
|
struct event_trigger_ops *ops; |
|
|
|
/* we register both traceon and traceoff to this callback */ |
|
if (strcmp(cmd, "traceon") == 0) |
|
ops = param ? &traceon_count_trigger_ops : |
|
&traceon_trigger_ops; |
|
else |
|
ops = param ? &traceoff_count_trigger_ops : |
|
&traceoff_trigger_ops; |
|
|
|
return ops; |
|
} |
|
|
|
static struct event_command trigger_traceon_cmd = { |
|
.name = "traceon", |
|
.trigger_type = ETT_TRACE_ONOFF, |
|
.func = event_trigger_callback, |
|
.reg = register_trigger, |
|
.unreg = unregister_trigger, |
|
.get_trigger_ops = onoff_get_trigger_ops, |
|
.set_filter = set_trigger_filter, |
|
}; |
|
|
|
static struct event_command trigger_traceoff_cmd = { |
|
.name = "traceoff", |
|
.trigger_type = ETT_TRACE_ONOFF, |
|
.flags = EVENT_CMD_FL_POST_TRIGGER, |
|
.func = event_trigger_callback, |
|
.reg = register_trigger, |
|
.unreg = unregister_trigger, |
|
.get_trigger_ops = onoff_get_trigger_ops, |
|
.set_filter = set_trigger_filter, |
|
}; |
|
|
|
#ifdef CONFIG_TRACER_SNAPSHOT |
|
static void |
|
snapshot_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
struct trace_event_file *file = data->private_data; |
|
|
|
if (file) |
|
tracing_snapshot_instance(file->tr); |
|
else |
|
tracing_snapshot(); |
|
} |
|
|
|
static void |
|
snapshot_count_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
if (!data->count) |
|
return; |
|
|
|
if (data->count != -1) |
|
(data->count)--; |
|
|
|
snapshot_trigger(data, rec, event); |
|
} |
|
|
|
static int |
|
register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, |
|
struct event_trigger_data *data, |
|
struct trace_event_file *file) |
|
{ |
|
if (tracing_alloc_snapshot_instance(file->tr) != 0) |
|
return 0; |
|
|
|
return register_trigger(glob, ops, data, file); |
|
} |
|
|
|
static int |
|
snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
return event_trigger_print("snapshot", m, (void *)data->count, |
|
data->filter_str); |
|
} |
|
|
|
static struct event_trigger_ops snapshot_trigger_ops = { |
|
.func = snapshot_trigger, |
|
.print = snapshot_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops snapshot_count_trigger_ops = { |
|
.func = snapshot_count_trigger, |
|
.print = snapshot_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops * |
|
snapshot_get_trigger_ops(char *cmd, char *param) |
|
{ |
|
return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; |
|
} |
|
|
|
static struct event_command trigger_snapshot_cmd = { |
|
.name = "snapshot", |
|
.trigger_type = ETT_SNAPSHOT, |
|
.func = event_trigger_callback, |
|
.reg = register_snapshot_trigger, |
|
.unreg = unregister_trigger, |
|
.get_trigger_ops = snapshot_get_trigger_ops, |
|
.set_filter = set_trigger_filter, |
|
}; |
|
|
|
static __init int register_trigger_snapshot_cmd(void) |
|
{ |
|
int ret; |
|
|
|
ret = register_event_command(&trigger_snapshot_cmd); |
|
WARN_ON(ret < 0); |
|
|
|
return ret; |
|
} |
|
#else |
|
static __init int register_trigger_snapshot_cmd(void) { return 0; } |
|
#endif /* CONFIG_TRACER_SNAPSHOT */ |
|
|
|
#ifdef CONFIG_STACKTRACE |
|
#ifdef CONFIG_UNWINDER_ORC |
|
/* Skip 2: |
|
* event_triggers_post_call() |
|
* trace_event_raw_event_xxx() |
|
*/ |
|
# define STACK_SKIP 2 |
|
#else |
|
/* |
|
* Skip 4: |
|
* stacktrace_trigger() |
|
* event_triggers_post_call() |
|
* trace_event_buffer_commit() |
|
* trace_event_raw_event_xxx() |
|
*/ |
|
#define STACK_SKIP 4 |
|
#endif |
|
|
|
static void |
|
stacktrace_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
trace_dump_stack(STACK_SKIP); |
|
} |
|
|
|
static void |
|
stacktrace_count_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
if (!data->count) |
|
return; |
|
|
|
if (data->count != -1) |
|
(data->count)--; |
|
|
|
stacktrace_trigger(data, rec, event); |
|
} |
|
|
|
static int |
|
stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
return event_trigger_print("stacktrace", m, (void *)data->count, |
|
data->filter_str); |
|
} |
|
|
|
static struct event_trigger_ops stacktrace_trigger_ops = { |
|
.func = stacktrace_trigger, |
|
.print = stacktrace_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops stacktrace_count_trigger_ops = { |
|
.func = stacktrace_count_trigger, |
|
.print = stacktrace_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops * |
|
stacktrace_get_trigger_ops(char *cmd, char *param) |
|
{ |
|
return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; |
|
} |
|
|
|
static struct event_command trigger_stacktrace_cmd = { |
|
.name = "stacktrace", |
|
.trigger_type = ETT_STACKTRACE, |
|
.flags = EVENT_CMD_FL_POST_TRIGGER, |
|
.func = event_trigger_callback, |
|
.reg = register_trigger, |
|
.unreg = unregister_trigger, |
|
.get_trigger_ops = stacktrace_get_trigger_ops, |
|
.set_filter = set_trigger_filter, |
|
}; |
|
|
|
static __init int register_trigger_stacktrace_cmd(void) |
|
{ |
|
int ret; |
|
|
|
ret = register_event_command(&trigger_stacktrace_cmd); |
|
WARN_ON(ret < 0); |
|
|
|
return ret; |
|
} |
|
#else |
|
static __init int register_trigger_stacktrace_cmd(void) { return 0; } |
|
#endif /* CONFIG_STACKTRACE */ |
|
|
|
static __init void unregister_trigger_traceon_traceoff_cmds(void) |
|
{ |
|
unregister_event_command(&trigger_traceon_cmd); |
|
unregister_event_command(&trigger_traceoff_cmd); |
|
} |
|
|
|
static void |
|
event_enable_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
struct enable_trigger_data *enable_data = data->private_data; |
|
|
|
if (enable_data->enable) |
|
clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
|
else |
|
set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
|
} |
|
|
|
static void |
|
event_enable_count_trigger(struct event_trigger_data *data, void *rec, |
|
struct ring_buffer_event *event) |
|
{ |
|
struct enable_trigger_data *enable_data = data->private_data; |
|
|
|
if (!data->count) |
|
return; |
|
|
|
/* Skip if the event is in a state we want to switch to */ |
|
if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
|
return; |
|
|
|
if (data->count != -1) |
|
(data->count)--; |
|
|
|
event_enable_trigger(data, rec, event); |
|
} |
|
|
|
int event_enable_trigger_print(struct seq_file *m, |
|
struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
struct enable_trigger_data *enable_data = data->private_data; |
|
|
|
seq_printf(m, "%s:%s:%s", |
|
enable_data->hist ? |
|
(enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) : |
|
(enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR), |
|
enable_data->file->event_call->class->system, |
|
trace_event_name(enable_data->file->event_call)); |
|
|
|
if (data->count == -1) |
|
seq_puts(m, ":unlimited"); |
|
else |
|
seq_printf(m, ":count=%ld", data->count); |
|
|
|
if (data->filter_str) |
|
seq_printf(m, " if %s\n", data->filter_str); |
|
else |
|
seq_putc(m, '\n'); |
|
|
|
return 0; |
|
} |
|
|
|
void event_enable_trigger_free(struct event_trigger_ops *ops, |
|
struct event_trigger_data *data) |
|
{ |
|
struct enable_trigger_data *enable_data = data->private_data; |
|
|
|
if (WARN_ON_ONCE(data->ref <= 0)) |
|
return; |
|
|
|
data->ref--; |
|
if (!data->ref) { |
|
/* Remove the SOFT_MODE flag */ |
|
trace_event_enable_disable(enable_data->file, 0, 1); |
|
module_put(enable_data->file->event_call->mod); |
|
trigger_data_free(data); |
|
kfree(enable_data); |
|
} |
|
} |
|
|
|
static struct event_trigger_ops event_enable_trigger_ops = { |
|
.func = event_enable_trigger, |
|
.print = event_enable_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_enable_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops event_enable_count_trigger_ops = { |
|
.func = event_enable_count_trigger, |
|
.print = event_enable_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_enable_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops event_disable_trigger_ops = { |
|
.func = event_enable_trigger, |
|
.print = event_enable_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_enable_trigger_free, |
|
}; |
|
|
|
static struct event_trigger_ops event_disable_count_trigger_ops = { |
|
.func = event_enable_count_trigger, |
|
.print = event_enable_trigger_print, |
|
.init = event_trigger_init, |
|
.free = event_enable_trigger_free, |
|
}; |
|
|
|
int event_enable_trigger_func(struct event_command *cmd_ops, |
|
struct trace_event_file *file, |
|
char *glob, char *cmd, char *param) |
|
{ |
|
struct trace_event_file *event_enable_file; |
|
struct enable_trigger_data *enable_data; |
|
struct event_trigger_data *trigger_data; |
|
struct event_trigger_ops *trigger_ops; |
|
struct trace_array *tr = file->tr; |
|
const char *system; |
|
const char *event; |
|
bool hist = false; |
|
char *trigger; |
|
char *number; |
|
bool enable; |
|
int ret; |
|
|
|
if (!param) |
|
return -EINVAL; |
|
|
|
/* separate the trigger from the filter (s:e:n [if filter]) */ |
|
trigger = strsep(¶m, " \t"); |
|
if (!trigger) |
|
return -EINVAL; |
|
if (param) { |
|
param = skip_spaces(param); |
|
if (!*param) |
|
param = NULL; |
|
} |
|
|
|
system = strsep(&trigger, ":"); |
|
if (!trigger) |
|
return -EINVAL; |
|
|
|
event = strsep(&trigger, ":"); |
|
|
|
ret = -EINVAL; |
|
event_enable_file = find_event_file(tr, system, event); |
|
if (!event_enable_file) |
|
goto out; |
|
|
|
#ifdef CONFIG_HIST_TRIGGERS |
|
hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) || |
|
(strcmp(cmd, DISABLE_HIST_STR) == 0)); |
|
|
|
enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || |
|
(strcmp(cmd, ENABLE_HIST_STR) == 0)); |
|
#else |
|
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
|
#endif |
|
trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); |
|
|
|
ret = -ENOMEM; |
|
trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); |
|
if (!trigger_data) |
|
goto out; |
|
|
|
enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); |
|
if (!enable_data) { |
|
kfree(trigger_data); |
|
goto out; |
|
} |
|
|
|
trigger_data->count = -1; |
|
trigger_data->ops = trigger_ops; |
|
trigger_data->cmd_ops = cmd_ops; |
|
INIT_LIST_HEAD(&trigger_data->list); |
|
RCU_INIT_POINTER(trigger_data->filter, NULL); |
|
|
|
enable_data->hist = hist; |
|
enable_data->enable = enable; |
|
enable_data->file = event_enable_file; |
|
trigger_data->private_data = enable_data; |
|
|
|
if (glob[0] == '!') { |
|
cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); |
|
kfree(trigger_data); |
|
kfree(enable_data); |
|
ret = 0; |
|
goto out; |
|
} |
|
|
|
/* Up the trigger_data count to make sure nothing frees it on failure */ |
|
event_trigger_init(trigger_ops, trigger_data); |
|
|
|
if (trigger) { |
|
number = strsep(&trigger, ":"); |
|
|
|
ret = -EINVAL; |
|
if (!strlen(number)) |
|
goto out_free; |
|
|
|
/* |
|
* We use the callback data field (which is a pointer) |
|
* as our counter. |
|
*/ |
|
ret = kstrtoul(number, 0, &trigger_data->count); |
|
if (ret) |
|
goto out_free; |
|
} |
|
|
|
if (!param) /* if param is non-empty, it's supposed to be a filter */ |
|
goto out_reg; |
|
|
|
if (!cmd_ops->set_filter) |
|
goto out_reg; |
|
|
|
ret = cmd_ops->set_filter(param, trigger_data, file); |
|
if (ret < 0) |
|
goto out_free; |
|
|
|
out_reg: |
|
/* Don't let event modules unload while probe registered */ |
|
ret = try_module_get(event_enable_file->event_call->mod); |
|
if (!ret) { |
|
ret = -EBUSY; |
|
goto out_free; |
|
} |
|
|
|
ret = trace_event_enable_disable(event_enable_file, 1, 1); |
|
if (ret < 0) |
|
goto out_put; |
|
ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); |
|
/* |
|
* The above returns on success the # of functions enabled, |
|
* but if it didn't find any functions it returns zero. |
|
* Consider no functions a failure too. |
|
*/ |
|
if (!ret) { |
|
ret = -ENOENT; |
|
goto out_disable; |
|
} else if (ret < 0) |
|
goto out_disable; |
|
/* Just return zero, not the number of enabled functions */ |
|
ret = 0; |
|
event_trigger_free(trigger_ops, trigger_data); |
|
out: |
|
return ret; |
|
|
|
out_disable: |
|
trace_event_enable_disable(event_enable_file, 0, 1); |
|
out_put: |
|
module_put(event_enable_file->event_call->mod); |
|
out_free: |
|
if (cmd_ops->set_filter) |
|
cmd_ops->set_filter(NULL, trigger_data, NULL); |
|
event_trigger_free(trigger_ops, trigger_data); |
|
kfree(enable_data); |
|
goto out; |
|
} |
|
|
|
int event_enable_register_trigger(char *glob, |
|
struct event_trigger_ops *ops, |
|
struct event_trigger_data *data, |
|
struct trace_event_file *file) |
|
{ |
|
struct enable_trigger_data *enable_data = data->private_data; |
|
struct enable_trigger_data *test_enable_data; |
|
struct event_trigger_data *test; |
|
int ret = 0; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
list_for_each_entry(test, &file->triggers, list) { |
|
test_enable_data = test->private_data; |
|
if (test_enable_data && |
|
(test->cmd_ops->trigger_type == |
|
data->cmd_ops->trigger_type) && |
|
(test_enable_data->file == enable_data->file)) { |
|
ret = -EEXIST; |
|
goto out; |
|
} |
|
} |
|
|
|
if (data->ops->init) { |
|
ret = data->ops->init(data->ops, data); |
|
if (ret < 0) |
|
goto out; |
|
} |
|
|
|
list_add_rcu(&data->list, &file->triggers); |
|
ret++; |
|
|
|
update_cond_flag(file); |
|
if (trace_event_trigger_enable_disable(file, 1) < 0) { |
|
list_del_rcu(&data->list); |
|
update_cond_flag(file); |
|
ret--; |
|
} |
|
out: |
|
return ret; |
|
} |
|
|
|
void event_enable_unregister_trigger(char *glob, |
|
struct event_trigger_ops *ops, |
|
struct event_trigger_data *test, |
|
struct trace_event_file *file) |
|
{ |
|
struct enable_trigger_data *test_enable_data = test->private_data; |
|
struct enable_trigger_data *enable_data; |
|
struct event_trigger_data *data; |
|
bool unregistered = false; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
list_for_each_entry(data, &file->triggers, list) { |
|
enable_data = data->private_data; |
|
if (enable_data && |
|
(data->cmd_ops->trigger_type == |
|
test->cmd_ops->trigger_type) && |
|
(enable_data->file == test_enable_data->file)) { |
|
unregistered = true; |
|
list_del_rcu(&data->list); |
|
trace_event_trigger_enable_disable(file, 0); |
|
update_cond_flag(file); |
|
break; |
|
} |
|
} |
|
|
|
if (unregistered && data->ops->free) |
|
data->ops->free(data->ops, data); |
|
} |
|
|
|
static struct event_trigger_ops * |
|
event_enable_get_trigger_ops(char *cmd, char *param) |
|
{ |
|
struct event_trigger_ops *ops; |
|
bool enable; |
|
|
|
#ifdef CONFIG_HIST_TRIGGERS |
|
enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || |
|
(strcmp(cmd, ENABLE_HIST_STR) == 0)); |
|
#else |
|
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
|
#endif |
|
if (enable) |
|
ops = param ? &event_enable_count_trigger_ops : |
|
&event_enable_trigger_ops; |
|
else |
|
ops = param ? &event_disable_count_trigger_ops : |
|
&event_disable_trigger_ops; |
|
|
|
return ops; |
|
} |
|
|
|
static struct event_command trigger_enable_cmd = { |
|
.name = ENABLE_EVENT_STR, |
|
.trigger_type = ETT_EVENT_ENABLE, |
|
.func = event_enable_trigger_func, |
|
.reg = event_enable_register_trigger, |
|
.unreg = event_enable_unregister_trigger, |
|
.get_trigger_ops = event_enable_get_trigger_ops, |
|
.set_filter = set_trigger_filter, |
|
}; |
|
|
|
static struct event_command trigger_disable_cmd = { |
|
.name = DISABLE_EVENT_STR, |
|
.trigger_type = ETT_EVENT_ENABLE, |
|
.func = event_enable_trigger_func, |
|
.reg = event_enable_register_trigger, |
|
.unreg = event_enable_unregister_trigger, |
|
.get_trigger_ops = event_enable_get_trigger_ops, |
|
.set_filter = set_trigger_filter, |
|
}; |
|
|
|
static __init void unregister_trigger_enable_disable_cmds(void) |
|
{ |
|
unregister_event_command(&trigger_enable_cmd); |
|
unregister_event_command(&trigger_disable_cmd); |
|
} |
|
|
|
static __init int register_trigger_enable_disable_cmds(void) |
|
{ |
|
int ret; |
|
|
|
ret = register_event_command(&trigger_enable_cmd); |
|
if (WARN_ON(ret < 0)) |
|
return ret; |
|
ret = register_event_command(&trigger_disable_cmd); |
|
if (WARN_ON(ret < 0)) |
|
unregister_trigger_enable_disable_cmds(); |
|
|
|
return ret; |
|
} |
|
|
|
static __init int register_trigger_traceon_traceoff_cmds(void) |
|
{ |
|
int ret; |
|
|
|
ret = register_event_command(&trigger_traceon_cmd); |
|
if (WARN_ON(ret < 0)) |
|
return ret; |
|
ret = register_event_command(&trigger_traceoff_cmd); |
|
if (WARN_ON(ret < 0)) |
|
unregister_trigger_traceon_traceoff_cmds(); |
|
|
|
return ret; |
|
} |
|
|
|
__init int register_trigger_cmds(void) |
|
{ |
|
register_trigger_traceon_traceoff_cmds(); |
|
register_trigger_snapshot_cmd(); |
|
register_trigger_stacktrace_cmd(); |
|
register_trigger_enable_disable_cmds(); |
|
register_trigger_hist_enable_disable_cmds(); |
|
register_trigger_hist_cmd(); |
|
|
|
return 0; |
|
}
|
|
|