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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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SPDX-License-Identifier: GPL-2.0/* * trace_events_trigger - trace event triggers * * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> */
#include <linux/security.h>#include <linux/kthread.h>#include <linux/module.h>#include <linux/ctype.h>#include <linux/mutex.h>#include <linux/slab.h>#include <linux/rculist.h>
#include "trace.h"
static LIST_HEAD(trigger_commands);static DEFINE_MUTEX(trigger_cmd_mutex);
static struct task_struct *trigger_kthread;static struct llist_head trigger_data_free_list;static DEFINE_MUTEX(trigger_data_kthread_mutex);
static int trigger_kthread_fn(void *ignore);
static void trigger_create_kthread_locked(void){ lockdep_assert_held(&trigger_data_kthread_mutex);
if (!trigger_kthread) { struct task_struct *kthread;
kthread = kthread_create(trigger_kthread_fn, NULL, "trigger_data_free"); if (!IS_ERR(kthread)) WRITE_ONCE(trigger_kthread, kthread); }}
static void trigger_data_free_one(struct event_trigger_data *data){ if (data->private_data_free) data->private_data_free(data); kfree(data);}
static void trigger_data_free_queued_locked(void){ struct event_trigger_data *data, *tmp; struct llist_node *llnodes;
lockdep_assert_held(&trigger_data_kthread_mutex);
llnodes = llist_del_all(&trigger_data_free_list); if (!llnodes) return;
tracepoint_synchronize_unregister();
llist_for_each_entry_safe(data, tmp, llnodes, llist) trigger_data_free_one(data);}
/* Bulk garbage collection of event_trigger_data elements */static int trigger_kthread_fn(void *ignore){ struct event_trigger_data *data, *tmp; struct llist_node *llnodes;
/* Once this task starts, it lives forever */ for (;;) { set_current_state(TASK_INTERRUPTIBLE); if (llist_empty(&trigger_data_free_list)) schedule();
__set_current_state(TASK_RUNNING);
llnodes = llist_del_all(&trigger_data_free_list);
/* make sure current triggers exit before free */ tracepoint_synchronize_unregister();
llist_for_each_entry_safe(data, tmp, llnodes, llist) trigger_data_free_one(data); }
return 0;}
void trigger_data_free(struct event_trigger_data *data){ if (!data) return;
if (data->cmd_ops->set_filter) data->cmd_ops->set_filter(NULL, data, NULL);
/* * Boot-time trigger registration can fail before kthread creation * works. Keep the deferred-free semantics during boot and let late * init start the kthread to drain the list. */ if (system_state == SYSTEM_BOOTING && !trigger_kthread) { llist_add(&data->llist, &trigger_data_free_list); return; }
if (unlikely(!trigger_kthread)) { guard(mutex)(&trigger_data_kthread_mutex);
trigger_create_kthread_locked(); /* Check again after taking mutex */ if (!trigger_kthread) { llist_add(&data->llist, &trigger_data_free_list); /* Drain the queued frees synchronously if creation failed. */ trigger_data_free_queued_locked(); return; } }
llist_add(&data->llist, &trigger_data_free_list); wake_up_process(trigger_kthread);}
static int __init trigger_data_free_init(void){ guard(mutex)(&trigger_data_kthread_mutex);
if (llist_empty(&trigger_data_free_list)) return 0;
trigger_create_kthread_locked(); if (trigger_kthread) wake_up_process(trigger_kthread); else trigger_data_free_queued_locked();
return 0;}late_initcall(trigger_data_free_init);
static inline void data_ops_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ const struct event_command *cmd_ops = data->cmd_ops;
if (data->flags & EVENT_TRIGGER_FL_COUNT) { if (!cmd_ops->count_func(data, buffer, rec, event)) return; }
cmd_ops->trigger(data, buffer, rec, event);}
/** * event_triggers_call - Call triggers associated with a trace event * @file: The trace_event_file associated with the event * @buffer: The ring buffer that the event is being written to * @rec: The trace entry for the event, NULL for unconditional invocation * @event: The event meta data in the ring buffer * * For each trigger associated with an event, invoke the trigger * function registered with the associated trigger command. If rec is * non-NULL, it means that the trigger requires further processing and * shouldn't be unconditionally invoked. If rec is non-NULL and the * trigger has a filter associated with it, rec will checked against * the filter and if the record matches the trigger will be invoked. * If the trigger is a 'post_trigger', meaning it shouldn't be invoked * in any case until the current event is written, the trigger * function isn't invoked but the bit associated with the deferred * trigger is set in the return value. * * Returns an enum event_trigger_type value containing a set bit for * any trigger that should be deferred, ETT_NONE if nothing to defer. * * Called from tracepoint handlers (with rcu_read_lock_sched() held). * * Return: an enum event_trigger_type value containing a set bit for * any trigger that should be deferred, ETT_NONE if nothing to defer. */enum event_trigger_typeevent_triggers_call(struct trace_event_file *file, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct event_trigger_data *data; enum event_trigger_type tt = ETT_NONE; struct event_filter *filter;
if (list_empty(&file->triggers)) return tt;
list_for_each_entry_rcu(data, &file->triggers, list) { if (data->paused) continue; if (!rec) { data_ops_trigger(data, buffer, rec, event); continue; } filter = rcu_dereference_sched(data->filter); if (filter && !filter_match_preds(filter, rec)) continue; if (event_command_post_trigger(data->cmd_ops)) { tt |= data->cmd_ops->trigger_type; continue; } data_ops_trigger(data, buffer, rec, event); } return tt;}EXPORT_SYMBOL_GPL(event_triggers_call);
bool __trace_trigger_soft_disabled(struct trace_event_file *file){ unsigned long eflags = file->flags;
if (eflags & EVENT_FILE_FL_TRIGGER_MODE) event_triggers_call(file, NULL, NULL, NULL); if (eflags & EVENT_FILE_FL_SOFT_DISABLED) return true; if (eflags & EVENT_FILE_FL_PID_FILTER) return trace_event_ignore_this_pid(file); return false;}EXPORT_SYMBOL_GPL(__trace_trigger_soft_disabled);
/** * event_triggers_post_call - Call 'post_triggers' for a trace event * @file: The trace_event_file associated with the event * @tt: enum event_trigger_type containing a set bit for each trigger to invoke * * 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. * See @event_triggers_call for details on how those bits are set. * * Called from tracepoint handlers (with rcu_read_lock_sched() held). */voidevent_triggers_post_call(struct trace_event_file *file, enum event_trigger_type tt){ struct event_trigger_data *data;
list_for_each_entry_rcu(data, &file->triggers, list) { if (data->paused) continue; if (data->cmd_ops->trigger_type & tt) data_ops_trigger(data, NULL, NULL, NULL); }}EXPORT_SYMBOL_GPL(event_triggers_post_call);
#define SHOW_AVAILABLE_TRIGGERS (void *)(1UL)
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) { (*pos)++; return NULL; } return seq_list_next(t, &event_file->triggers, pos);}
static bool check_user_trigger(struct trace_event_file *file){ struct event_trigger_data *data;
list_for_each_entry_rcu(data, &file->triggers, list, lockdep_is_held(&event_mutex)) { if (data->flags & EVENT_TRIGGER_FL_PROBE) continue; return true; } return false;}
static void *trigger_start(struct seq_file *m, loff_t *pos){ struct trace_event_file *event_file;
/* ->stop() is called even if ->start() fails */ mutex_lock(&event_mutex); event_file = event_file_file(m->private); if (unlikely(!event_file)) return ERR_PTR(-ENODEV);
if (list_empty(&event_file->triggers) || !check_user_trigger(event_file)) return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL;
return seq_list_start(&event_file->triggers, *pos);}
static void trigger_stop(struct seq_file *m, void *t){ mutex_unlock(&event_mutex);}
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) seq_printf(m, " %s", p->name); seq_putc(m, '\n'); mutex_unlock(&trigger_cmd_mutex); return 0; }
data = list_entry(v, struct event_trigger_data, list); data->cmd_ops->print(m, data);
return 0;}
static const struct seq_operations event_triggers_seq_ops = { .start = trigger_start, .next = trigger_next, .stop = trigger_stop, .show = trigger_show,};
static int event_trigger_regex_open(struct inode *inode, struct file *file){ int ret;
ret = security_locked_down(LOCKDOWN_TRACEFS); if (ret) return ret;
guard(mutex)(&event_mutex);
if (unlikely(!event_file_file(file))) return -ENODEV;
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { struct trace_event_file *event_file; struct event_command *p;
event_file = event_file_data(file);
list_for_each_entry(p, &trigger_commands, list) { if (p->unreg_all) p->unreg_all(event_file); } }
if (file->f_mode & FMODE_READ) { ret = seq_open(file, &event_triggers_seq_ops); if (!ret) { struct seq_file *m = file->private_data; m->private = file; } }
return ret;}
int trigger_process_regex(struct trace_event_file *file, char *buff){ char *command, *next; struct event_command *p;
next = buff = strim(buff);
command = strsep(&next, ": \t"); if (next) { next = skip_spaces(next); if (!*next) next = NULL; } command = (command[0] != '!') ? command : command + 1;
guard(mutex)(&trigger_cmd_mutex);
list_for_each_entry(p, &trigger_commands, list) { if (strcmp(p->name, command) == 0) return p->parse(p, file, buff, command, next); }
return -EINVAL;}
static ssize_t event_trigger_regex_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos){ struct trace_event_file *event_file; ssize_t ret; char *buf __free(kfree) = NULL;
if (!cnt) return 0;
if (cnt >= PAGE_SIZE) return -EINVAL;
buf = memdup_user_nul(ubuf, cnt); if (IS_ERR(buf)) return PTR_ERR(buf);
guard(mutex)(&event_mutex);
event_file = event_file_file(file); if (unlikely(!event_file)) return -ENODEV;
ret = trigger_process_regex(event_file, buf); if (ret < 0) return ret;
*ppos += cnt; return cnt;}
static int event_trigger_regex_release(struct inode *inode, struct file *file){ if (file->f_mode & FMODE_READ) seq_release(inode, file);
return 0;}
static ssize_tevent_trigger_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos){ return event_trigger_regex_write(filp, ubuf, cnt, ppos);}
static intevent_trigger_open(struct inode *inode, struct file *filp){ /* Checks for tracefs lockdown */ return event_trigger_regex_open(inode, filp);}
static intevent_trigger_release(struct inode *inode, struct file *file){ return event_trigger_regex_release(inode, file);}
const struct file_operations event_trigger_fops = { .open = event_trigger_open, .read = seq_read, .write = event_trigger_write, .llseek = tracing_lseek, .release = event_trigger_release,};
/* * Currently we only register event commands from __init, so mark this * __init too. */__init int register_event_command(struct event_command *cmd){ struct event_command *p;
guard(mutex)(&trigger_cmd_mutex);
list_for_each_entry(p, &trigger_commands, list) { if (strcmp(cmd->name, p->name) == 0) return -EBUSY; } list_add(&cmd->list, &trigger_commands);
return 0;}
/* * Currently we only unregister event commands from __init, so mark * this __init too. */__init int unregister_event_command(struct event_command *cmd){ struct event_command *p, *n;
guard(mutex)(&trigger_cmd_mutex);
list_for_each_entry_safe(p, n, &trigger_commands, list) { if (strcmp(cmd->name, p->name) == 0) { list_del_init(&p->list); return 0; } }
return -ENODEV;}
/** * event_trigger_count - Optional count function for event triggers * @data: Trigger-specific data * @buffer: The ring buffer that the event is being written to * @rec: The trace entry for the event, NULL for unconditional invocation * @event: The event meta data in the ring buffer * * For triggers that can take a count parameter that doesn't do anything * special, they can use this function to assign to their .count_func * field. * * This simply does a count down of the @data->count field. * * If the @data->count is greater than zero, it will decrement it. * * Returns false if @data->count is zero, otherwise true. */bool event_trigger_count(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ if (!data->count) return false;
if (data->count != -1) (data->count)--;
return true;}
/** * event_trigger_print - Generic event_command @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 intevent_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_command @init implementation * @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_data *data){ data->ref++; return 0;}
/** * event_trigger_free - Generic event_command @free implementation * @data: Trigger-specific data * * Common implementation of event trigger de-initialization. * * Usually used directly as the @free method in event trigger * implementations. */static voidevent_trigger_free(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. */voidclear_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->cmd_ops->free) data->cmd_ops->free(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 * @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_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) return -EEXIST; }
if (data->cmd_ops->init) { ret = data->cmd_ops->init(data); if (ret < 0) return ret; }
list_add_rcu(&data->list, &file->triggers);
update_cond_flag(file); ret = trace_event_trigger_enable_disable(file, 1); if (ret < 0) { list_del_rcu(&data->list); update_cond_flag(file); } return ret;}
/* * True if the trigger was found and unregistered, else false. */static bool try_unregister_trigger(char *glob, struct event_trigger_data *test, struct trace_event_file *file){ struct event_trigger_data *data = NULL, *iter;
lockdep_assert_held(&event_mutex);
list_for_each_entry(iter, &file->triggers, list) { if (iter->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { data = iter; list_del_rcu(&data->list); trace_event_trigger_enable_disable(file, 0); update_cond_flag(file); break; } }
if (data) { if (data->cmd_ops->free) data->cmd_ops->free(data);
return true; }
return false;}
/** * unregister_trigger - Generic event_command @unreg implementation * @glob: The raw string used to register 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_data *test, struct trace_event_file *file){ try_unregister_trigger(glob, test, file);}
/* * Event trigger parsing helper functions. * * These functions help make it easier to write an event trigger * parsing function i.e. the struct event_command.parse() callback * function responsible for parsing and registering a trigger command * written to the 'trigger' file. * * A trigger command (or just 'trigger' for short) takes the form: * [trigger] [if filter] * * The struct event_command.parse() callback (and other struct * event_command functions) refer to several components of a trigger * command. Those same components are referenced by the event trigger * parsing helper functions defined below. These components are: * * cmd - the trigger command name * glob - the trigger command name optionally prefaced with '!' * param_and_filter - text following cmd and ':' * param - text following cmd and ':' and stripped of filter * filter - the optional filter text following (and including) 'if' * * To illustrate the use of these components, here are some concrete * examples. For the following triggers: * * echo 'traceon:5 if pid == 0' > trigger * - 'traceon' is both cmd and glob * - '5 if pid == 0' is the param_and_filter * - '5' is the param * - 'if pid == 0' is the filter * * echo 'enable_event:sys:event:n' > trigger * - 'enable_event' is both cmd and glob * - 'sys:event:n' is the param_and_filter * - 'sys:event:n' is the param * - there is no filter * * echo 'hist:keys=pid if prio > 50' > trigger * - 'hist' is both cmd and glob * - 'keys=pid if prio > 50' is the param_and_filter * - 'keys=pid' is the param * - 'if prio > 50' is the filter * * echo '!enable_event:sys:event:n' > trigger * - 'enable_event' the cmd * - '!enable_event' is the glob * - 'sys:event:n' is the param_and_filter * - 'sys:event:n' is the param * - there is no filter * * echo 'traceoff' > trigger * - 'traceoff' is both cmd and glob * - there is no param_and_filter * - there is no param * - there is no filter * * There are a few different categories of event trigger covered by * these helpers: * * - triggers that don't require a parameter e.g. traceon * - triggers that do require a parameter e.g. enable_event and hist * - triggers that though they may not require a param may support an * optional 'n' param (n = number of times the trigger should fire) * e.g.: traceon:5 or enable_event:sys:event:n * - triggers that do not support an 'n' param e.g. hist * * These functions can be used or ignored as necessary - it all * depends on the complexity of the trigger, and the granularity of * the functions supported reflects the fact that some implementations * may need to customize certain aspects of their implementations and * won't need certain functions. For instance, the hist trigger * implementation doesn't use event_trigger_separate_filter() because * it has special requirements for handling the filter. */
/** * event_trigger_check_remove - check whether an event trigger specifies remove * @glob: The trigger command string, with optional remove(!) operator * * The event trigger callback implementations pass in 'glob' as a * parameter. This is the command name either with or without a * remove(!) operator. This function simply parses the glob and * determines whether the command corresponds to a trigger removal or * a trigger addition. * * Return: true if this is a remove command, false otherwise */bool event_trigger_check_remove(const char *glob){ return (glob && glob[0] == '!') ? true : false;}
/** * event_trigger_empty_param - check whether the param is empty * @param: The trigger param string * * The event trigger callback implementations pass in 'param' as a * parameter. This corresponds to the string following the command * name minus the command name. This function can be called by a * callback implementation for any command that requires a param; a * callback that doesn't require a param can ignore it. * * Return: true if this is an empty param, false otherwise */bool event_trigger_empty_param(const char *param){ return !param;}
/** * event_trigger_separate_filter - separate an event trigger from a filter * @param_and_filter: String containing trigger and possibly filter * @param: outparam, will be filled with a pointer to the trigger * @filter: outparam, will be filled with a pointer to the filter * @param_required: Specifies whether or not the param string is required * * Given a param string of the form '[trigger] [if filter]', this * function separates the filter from the trigger and returns the * trigger in @param and the filter in @filter. Either the @param * or the @filter may be set to NULL by this function - if not set to * NULL, they will contain strings corresponding to the trigger and * filter. * * There are two cases that need to be handled with respect to the * passed-in param: either the param is required, or it is not * required. If @param_required is set, and there's no param, it will * return -EINVAL. If @param_required is not set and there's a param * that starts with a number, that corresponds to the case of a * trigger with :n (n = number of times the trigger should fire) and * the parsing continues normally; otherwise the function just returns * and assumes param just contains a filter and there's nothing else * to do. * * Return: 0 on success, errno otherwise */int event_trigger_separate_filter(char *param_and_filter, char **param, char **filter, bool param_required){ int ret = 0;
*param = *filter = NULL;
if (!param_and_filter) { if (param_required) ret = -EINVAL; return ret; }
/* * Here we check for an optional param. The only legal * optional param is :n, and if that's the case, continue * below. Otherwise we assume what's left is a filter and * return it as the filter string for the caller to deal with. */ if (!param_required && param_and_filter && !isdigit(param_and_filter[0])) { *filter = param_and_filter; return ret; }
/* * Separate the param from the filter (param [if filter]). * Here we have either an optional :n param or a required * param and an optional filter. */ *param = strsep(¶m_and_filter, " \t");
/* * Here we have a filter, though it may be empty. */ if (param_and_filter) { *filter = skip_spaces(param_and_filter); if (!**filter) *filter = NULL; } return ret;}
/** * trigger_data_alloc - allocate and init event_trigger_data for a trigger * @cmd_ops: The event_command operations for the trigger * @cmd: The cmd string * @param: The param string * @private_data: User data to associate with the event trigger * * Allocate an event_trigger_data instance and initialize it. The * @cmd_ops defines how the trigger will operate. If @param is set, * and @cmd_ops->trigger_ops->count_func is non NULL, then the * data->count is set to @param and before the trigger is executed, the * @cmd_ops->trigger_ops->count_func() is called. If that function returns * false, the @cmd_ops->trigger_ops->trigger() function will not be called. * @private_data can also be passed in and associated with the * event_trigger_data. * * Use trigger_data_free() to free an event_trigger_data object. * * Return: The trigger_data object success, NULL otherwise */struct event_trigger_data *trigger_data_alloc(struct event_command *cmd_ops, char *cmd, char *param, void *private_data){ struct event_trigger_data *trigger_data;
trigger_data = kzalloc_obj(*trigger_data); if (!trigger_data) return NULL;
trigger_data->count = -1; trigger_data->cmd_ops = cmd_ops; trigger_data->private_data = private_data; if (param && cmd_ops->count_func) trigger_data->flags |= EVENT_TRIGGER_FL_COUNT;
INIT_LIST_HEAD(&trigger_data->list); INIT_LIST_HEAD(&trigger_data->named_list); RCU_INIT_POINTER(trigger_data->filter, NULL);
return trigger_data;}
/** * event_trigger_parse_num - parse and return the number param for a trigger * @param: The param string * @trigger_data: The trigger_data for the trigger * * Parse the :n (n = number of times the trigger should fire) param * and set the count variable in the trigger_data to the parsed count. * * Return: 0 on success, errno otherwise */int event_trigger_parse_num(char *param, struct event_trigger_data *trigger_data){ char *number; int ret = 0;
if (param) { number = strsep(¶m, ":");
if (!strlen(number)) return -EINVAL;
/* * We use the callback data field (which is a pointer) * as our counter. */ ret = kstrtoul(number, 0, &trigger_data->count); }
return ret;}
/** * event_trigger_set_filter - set an event trigger's filter * @cmd_ops: The event_command operations for the trigger * @file: The event file for the trigger's event * @param: The string containing the filter * @trigger_data: The trigger_data for the trigger * * Set the filter for the trigger. If the filter is NULL, just return * without error. * * Return: 0 on success, errno otherwise */int event_trigger_set_filter(struct event_command *cmd_ops, struct trace_event_file *file, char *param, struct event_trigger_data *trigger_data){ if (param && cmd_ops->set_filter) return cmd_ops->set_filter(param, trigger_data, file);
return 0;}
/** * event_trigger_reset_filter - reset an event trigger's filter * @cmd_ops: The event_command operations for the trigger * @trigger_data: The trigger_data for the trigger * * Reset the filter for the trigger to no filter. */void event_trigger_reset_filter(struct event_command *cmd_ops, struct event_trigger_data *trigger_data){ if (cmd_ops->set_filter) cmd_ops->set_filter(NULL, trigger_data, NULL);}
/** * event_trigger_register - register an event trigger * @cmd_ops: The event_command operations for the trigger * @file: The event file for the trigger's event * @glob: The trigger command string, with optional remove(!) operator * @trigger_data: The trigger_data for the trigger * * Register an event trigger. The @cmd_ops are used to call the * cmd_ops->reg() function which actually does the registration. * * Return: 0 on success, errno otherwise */int event_trigger_register(struct event_command *cmd_ops, struct trace_event_file *file, char *glob, struct event_trigger_data *trigger_data){ return cmd_ops->reg(glob, trigger_data, file);}
/** * event_trigger_unregister - unregister an event trigger * @cmd_ops: The event_command operations for the trigger * @file: The event file for the trigger's event * @glob: The trigger command string, with optional remove(!) operator * @trigger_data: The trigger_data for the trigger * * Unregister an event trigger. The @cmd_ops are used to call the * cmd_ops->unreg() function which actually does the unregistration. */void event_trigger_unregister(struct event_command *cmd_ops, struct trace_event_file *file, char *glob, struct event_trigger_data *trigger_data){ cmd_ops->unreg(glob, trigger_data, file);}
/* * End event trigger parsing helper functions. */
/** * event_trigger_parse - Generic event_command @parse 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_and_filter: The param and filter portion of the string used to register the trigger * * Common implementation for event command parsing and trigger * instantiation. * * Usually used directly as the @parse method in event command * implementations. * * Return: 0 on success, errno otherwise */static intevent_trigger_parse(struct event_command *cmd_ops, struct trace_event_file *file, char *glob, char *cmd, char *param_and_filter){ struct event_trigger_data *trigger_data; char *param, *filter; bool remove; int ret;
remove = event_trigger_check_remove(glob);
ret = event_trigger_separate_filter(param_and_filter, ¶m, &filter, false); if (ret) return ret;
ret = -ENOMEM; trigger_data = trigger_data_alloc(cmd_ops, cmd, param, file); if (!trigger_data) return ret;
if (remove) { event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); trigger_data_free(trigger_data); return 0; }
ret = event_trigger_parse_num(param, trigger_data); if (ret) goto out_free;
ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); if (ret < 0) goto out_free;
/* Up the trigger_data count to make sure reg doesn't free it on failure */ event_trigger_init(trigger_data);
ret = event_trigger_register(cmd_ops, file, glob, trigger_data); if (ret) goto out_free;
/* Down the counter of trigger_data or free it if not used anymore */ event_trigger_free(trigger_data); return ret;
out_free: event_trigger_reset_filter(cmd_ops, trigger_data); trigger_data_free(trigger_data); return ret;}
/** * 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) return ret;
if (!filter_str) return ret;
/* The filter is for the 'trigger' event, not the triggered event */ ret = create_event_filter(file->tr, file->event_call, filter_str, true, &filter);
/* Only enabled set_str for error handling */ if (filter) { kfree(filter->filter_string); filter->filter_string = NULL; }
/* * 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. * It is possible that a filter could fail at boot up, * and then this path will be called. Avoid the synchronization * in that case. */ if (system_state != SYSTEM_BOOTING) 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; } } 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 to associate * @named_data: The common named trigger to be associated * * 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 voidtraceon_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct trace_event_file *file = data->private_data;
if (WARN_ON_ONCE(!file)) return;
if (tracer_tracing_is_on(file->tr)) return;
tracer_tracing_on(file->tr);}
static booltraceon_count_func(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct trace_event_file *file = data->private_data;
if (WARN_ON_ONCE(!file)) return false;
if (tracer_tracing_is_on(file->tr)) return false;
if (!data->count) return false;
if (data->count != -1) (data->count)--;
return true;}
static voidtraceoff_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct trace_event_file *file = data->private_data;
if (WARN_ON_ONCE(!file)) return;
if (!tracer_tracing_is_on(file->tr)) return;
tracer_tracing_off(file->tr);}
static booltraceoff_count_func(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct trace_event_file *file = data->private_data;
if (WARN_ON_ONCE(!file)) return false;
if (!tracer_tracing_is_on(file->tr)) return false;
if (!data->count) return false;
if (data->count != -1) (data->count)--;
return true;}
static inttraceon_trigger_print(struct seq_file *m, struct event_trigger_data *data){ return event_trigger_print("traceon", m, (void *)data->count, data->filter_str);}
static inttraceoff_trigger_print(struct seq_file *m, struct event_trigger_data *data){ return event_trigger_print("traceoff", m, (void *)data->count, data->filter_str);}
static struct event_command trigger_traceon_cmd = { .name = "traceon", .trigger_type = ETT_TRACE_ONOFF, .parse = event_trigger_parse, .reg = register_trigger, .unreg = unregister_trigger, .set_filter = set_trigger_filter, .trigger = traceon_trigger, .count_func = traceon_count_func, .print = traceon_trigger_print, .init = event_trigger_init, .free = event_trigger_free,};
static struct event_command trigger_traceoff_cmd = { .name = "traceoff", .trigger_type = ETT_TRACE_ONOFF, .flags = EVENT_CMD_FL_POST_TRIGGER, .parse = event_trigger_parse, .reg = register_trigger, .unreg = unregister_trigger, .set_filter = set_trigger_filter, .trigger = traceoff_trigger, .count_func = traceoff_count_func, .print = traceoff_trigger_print, .init = event_trigger_init, .free = event_trigger_free,};
#ifdef CONFIG_TRACER_SNAPSHOTstatic voidsnapshot_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct trace_event_file *file = data->private_data;
if (WARN_ON_ONCE(!file)) return;
tracing_snapshot_instance(file->tr);}
static intregister_snapshot_trigger(char *glob, struct event_trigger_data *data, struct trace_event_file *file){ int ret = tracing_arm_snapshot(file->tr);
if (ret < 0) return ret;
ret = register_trigger(glob, data, file); if (ret < 0) tracing_disarm_snapshot(file->tr); return ret;}
static void unregister_snapshot_trigger(char *glob, struct event_trigger_data *data, struct trace_event_file *file){ if (try_unregister_trigger(glob, data, file)) tracing_disarm_snapshot(file->tr);}
static intsnapshot_trigger_print(struct seq_file *m, struct event_trigger_data *data){ return event_trigger_print("snapshot", m, (void *)data->count, data->filter_str);}
static struct event_command trigger_snapshot_cmd = { .name = "snapshot", .trigger_type = ETT_SNAPSHOT, .parse = event_trigger_parse, .reg = register_snapshot_trigger, .unreg = unregister_snapshot_trigger, .set_filter = set_trigger_filter, .trigger = snapshot_trigger, .count_func = event_trigger_count, .print = snapshot_trigger_print, .init = event_trigger_init, .free = event_trigger_free,};
static __init int register_trigger_snapshot_cmd(void){ int ret;
ret = register_event_command(&trigger_snapshot_cmd); WARN_ON(ret < 0);
return ret;}#elsestatic __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 voidstacktrace_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct trace_event_file *file = data->private_data;
if (WARN_ON_ONCE(!file)) return;
__trace_stack(file->tr, tracing_gen_ctx_dec(), STACK_SKIP);}
static intstacktrace_trigger_print(struct seq_file *m, struct event_trigger_data *data){ return event_trigger_print("stacktrace", m, (void *)data->count, data->filter_str);}
static struct event_command trigger_stacktrace_cmd = { .name = "stacktrace", .trigger_type = ETT_STACKTRACE, .flags = EVENT_CMD_FL_POST_TRIGGER, .parse = event_trigger_parse, .reg = register_trigger, .unreg = unregister_trigger, .set_filter = set_trigger_filter, .trigger = stacktrace_trigger, .count_func = event_trigger_count, .print = stacktrace_trigger_print, .init = event_trigger_init, .free = event_trigger_free,};
static __init int register_trigger_stacktrace_cmd(void){ int ret;
ret = register_event_command(&trigger_stacktrace_cmd); WARN_ON(ret < 0);
return ret;}#elsestatic __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 voidevent_enable_trigger(struct event_trigger_data *data, struct trace_buffer *buffer, 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 boolevent_enable_count_func(struct event_trigger_data *data, struct trace_buffer *buffer, void *rec, struct ring_buffer_event *event){ struct enable_trigger_data *enable_data = data->private_data;
if (!data->count) return false;
/* 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 false;
if (data->count != -1) (data->count)--;
return true;}
int event_enable_trigger_print(struct seq_file *m, 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;}
static void enable_trigger_private_data_free(struct event_trigger_data *data){ struct enable_trigger_data *enable_data = data->private_data;
trace_event_put_ref(enable_data->file->event_call); kfree(enable_data);}
void event_enable_trigger_free(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); data->private_data_free = enable_trigger_private_data_free; trigger_data_free(data); }}
int event_enable_trigger_parse(struct event_command *cmd_ops, struct trace_event_file *file, char *glob, char *cmd, char *param_and_filter){ struct trace_event_file *event_enable_file; struct enable_trigger_data *enable_data; struct event_trigger_data *trigger_data; struct trace_array *tr = file->tr; char *param, *filter; bool enable, remove; const char *system; const char *event; bool hist = false; int ret;
remove = event_trigger_check_remove(glob);
if (event_trigger_empty_param(param_and_filter)) return -EINVAL;
ret = event_trigger_separate_filter(param_and_filter, ¶m, &filter, true); if (ret) return ret;
system = strsep(¶m, ":"); if (!param) return -EINVAL;
event = strsep(¶m, ":");
ret = -EINVAL; event_enable_file = find_event_file(tr, system, event); if (!event_enable_file) return ret;
#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 ret = -ENOMEM;
enable_data = kzalloc_obj(*enable_data); if (!enable_data) return ret;
enable_data->hist = hist; enable_data->enable = enable; enable_data->file = event_enable_file;
trigger_data = trigger_data_alloc(cmd_ops, cmd, param, enable_data); if (!trigger_data) { kfree(enable_data); return ret; }
if (remove) { event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); kfree(trigger_data); kfree(enable_data); ret = 0; return ret; }
/* Up the trigger_data count to make sure nothing frees it on failure */ event_trigger_init(trigger_data);
ret = event_trigger_parse_num(param, trigger_data); if (ret) goto out_free;
ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); if (ret < 0) goto out_free;
/* Don't let event modules unload while probe registered */ ret = trace_event_try_get_ref(event_enable_file->event_call); if (!ret) { ret = -EBUSY; goto out_free; }
ret = trace_event_enable_disable(event_enable_file, 1, 1); if (ret < 0) goto out_put;
ret = event_trigger_register(cmd_ops, file, glob, trigger_data); if (ret) goto out_disable;
event_trigger_free(trigger_data); return ret; out_disable: trace_event_enable_disable(event_enable_file, 0, 1); out_put: trace_event_put_ref(event_enable_file->event_call); out_free: event_trigger_reset_filter(cmd_ops, trigger_data); event_trigger_free(trigger_data); kfree(enable_data);
return ret;}
int event_enable_register_trigger(char *glob, 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)) { return -EEXIST; } }
if (data->cmd_ops->init) { ret = data->cmd_ops->init(data); if (ret < 0) return ret; }
list_add_rcu(&data->list, &file->triggers);
update_cond_flag(file); ret = trace_event_trigger_enable_disable(file, 1); if (ret < 0) { list_del_rcu(&data->list); update_cond_flag(file); } return ret;}
void event_enable_unregister_trigger(char *glob, struct event_trigger_data *test, struct trace_event_file *file){ struct enable_trigger_data *test_enable_data = test->private_data; struct event_trigger_data *data = NULL, *iter; struct enable_trigger_data *enable_data;
lockdep_assert_held(&event_mutex);
list_for_each_entry(iter, &file->triggers, list) { enable_data = iter->private_data; if (enable_data && (iter->cmd_ops->trigger_type == test->cmd_ops->trigger_type) && (enable_data->file == test_enable_data->file)) { data = iter; list_del_rcu(&data->list); trace_event_trigger_enable_disable(file, 0); update_cond_flag(file); break; } }
if (data && data->cmd_ops->free) data->cmd_ops->free(data);}
static struct event_command trigger_enable_cmd = { .name = ENABLE_EVENT_STR, .trigger_type = ETT_EVENT_ENABLE, .parse = event_enable_trigger_parse, .reg = event_enable_register_trigger, .unreg = event_enable_unregister_trigger, .set_filter = set_trigger_filter, .trigger = event_enable_trigger, .count_func = event_enable_count_func, .print = event_enable_trigger_print, .init = event_trigger_init, .free = event_enable_trigger_free,};
static struct event_command trigger_disable_cmd = { .name = DISABLE_EVENT_STR, .trigger_type = ETT_EVENT_ENABLE, .parse = event_enable_trigger_parse, .reg = event_enable_register_trigger, .unreg = event_enable_unregister_trigger, .set_filter = set_trigger_filter, .trigger = event_enable_trigger, .count_func = event_enable_count_func, .print = event_enable_trigger_print, .init = event_trigger_init, .free = event_enable_trigger_free,};
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;}