/*

* event tracer

*

* Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>

*

* - Added format output of fields of the trace point.

* This was based off of work by Tom Zanussi <tzanussi@gmail.com>.

*

*/

#define pr_fmt(fmt) fmt

#include <linux/workqueue.h>

#include <linux/spinlock.h>

#include <linux/kthread.h>

#include <linux/tracefs.h>

#include <linux/uaccess.h>

#include <linux/module.h>

#include <linux/ctype.h>

#include <linux/sort.h>

#include <linux/slab.h>

#include <linux/delay.h>

#include <trace/events/sched.h>

#include <asm/setup.h>

#include "trace_output.h"

#undef TRACE_SYSTEM

#define TRACE_SYSTEM "TRACE_SYSTEM"

DEFINE_MUTEX(event_mutex);

LIST_HEAD(ftrace_events);

static LIST_HEAD(ftrace_generic_fields);

static LIST_HEAD(ftrace_common_fields);

#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO)

static struct kmem_cache *field_cachep;

static struct kmem_cache *file_cachep;

static inline int system_refcount(struct event_subsystem *system)

{

return system->ref_count;

}

static int system_refcount_inc(struct event_subsystem *system)

{

return system->ref_count++;

}

static int system_refcount_dec(struct event_subsystem *system)

{

return --system->ref_count;

}

/* Double loops, do not use break, only goto's work */

#define do_for_each_event_file(tr, file) \

list_for_each_entry(tr, &ftrace_trace_arrays, list) { \

list_for_each_entry(file, &tr->events, list)

#define do_for_each_event_file_safe(tr, file) \

list_for_each_entry(tr, &ftrace_trace_arrays, list) { \

struct trace_event_file *___n; \

list_for_each_entry_safe(file, ___n, &tr->events, list)

#define while_for_each_event_file() \

}

static struct list_head *

trace_get_fields(struct trace_event_call *event_call)

{

if (!event_call->class->get_fields)

return &event_call->class->fields;

return event_call->class->get_fields(event_call);

}

static struct ftrace_event_field *

__find_event_field(struct list_head *head, char *name)

{

struct ftrace_event_field *field;

list_for_each_entry(field, head, link) {

if (!strcmp(field->name, name))

return field;

}

return NULL;

}

struct ftrace_event_field *

trace_find_event_field(struct trace_event_call *call, char *name)

{

struct ftrace_event_field *field;

struct list_head *head;

head = trace_get_fields(call);

field = __find_event_field(head, name);

if (field)

return field;

field = __find_event_field(&ftrace_generic_fields, name);

if (field)

return field;

return __find_event_field(&ftrace_common_fields, name);

}

static int __trace_define_field(struct list_head *head, const char *type,

const char *name, int offset, int size,

int is_signed, int filter_type)

{

struct ftrace_event_field *field;

field = kmem_cache_alloc(field_cachep, GFP_TRACE);

if (!field)

return -ENOMEM;

field->name = name;

field->type = type;

if (filter_type == FILTER_OTHER)

field->filter_type = filter_assign_type(type);

else

field->filter_type = filter_type;

field->offset = offset;

field->size = size;

field->is_signed = is_signed;

list_add(&field->link, head);

return 0;

}

int trace_define_field(struct trace_event_call *call, const char *type,

const char *name, int offset, int size, int is_signed,

int filter_type)

{

struct list_head *head;

if (WARN_ON(!call->class))

return 0;

head = trace_get_fields(call);

return __trace_define_field(head, type, name, offset, size,

is_signed, filter_type);

}

EXPORT_SYMBOL_GPL(trace_define_field);

#define __generic_field(type, item, filter_type) \

ret = __trace_define_field(&ftrace_generic_fields, #type, \

#item, 0, 0, is_signed_type(type), \

filter_type); \

if (ret) \

return ret;

#define __common_field(type, item) \

ret = __trace_define_field(&ftrace_common_fields, #type, \

"common_" #item, \

offsetof(typeof(ent), item), \

sizeof(ent.item), \

is_signed_type(type), FILTER_OTHER); \

if (ret) \

return ret;

static int trace_define_generic_fields(void)

{

int ret;

__generic_field(int, CPU, FILTER_CPU);

__generic_field(int, cpu, FILTER_CPU);

__generic_field(char *, COMM, FILTER_COMM);

__generic_field(char *, comm, FILTER_COMM);

return ret;

}

static int trace_define_common_fields(void)

{

int ret;

struct trace_entry ent;

__common_field(unsigned short, type);

__common_field(unsigned char, flags);

__common_field(unsigned char, preempt_count);

__common_field(int, pid);

return ret;

}

static void trace_destroy_fields(struct trace_event_call *call)

{

struct ftrace_event_field *field, *next;

struct list_head *head;

head = trace_get_fields(call);

list_for_each_entry_safe(field, next, head, link) {

list_del(&field->link);

kmem_cache_free(field_cachep, field);

}

}

/*

* run-time version of trace_event_get_offsets_<call>() that returns the last

* accessible offset of trace fields excluding __dynamic_array bytes

*/

int trace_event_get_offsets(struct trace_event_call *call)

{

struct ftrace_event_field *tail;

struct list_head *head;

head = trace_get_fields(call);

/*

* head->next points to the last field with the largest offset,

* since it was added last by trace_define_field()

*/

tail = list_first_entry(head, struct ftrace_event_field, link);

return tail->offset + tail->size;

}

int trace_event_raw_init(struct trace_event_call *call)

{

int id;

id = register_trace_event(&call->event);

if (!id)

return -ENODEV;

return 0;

}

EXPORT_SYMBOL_GPL(trace_event_raw_init);

bool trace_event_ignore_this_pid(struct trace_event_file *trace_file)

{

struct trace_array *tr = trace_file->tr;

struct trace_array_cpu *data;

struct trace_pid_list *pid_list;

pid_list = rcu_dereference_sched(tr->filtered_pids);

if (!pid_list)

return false;

data = this_cpu_ptr(tr->trace_buffer.data);

return data->ignore_pid;

}

EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid);

void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,

struct trace_event_file *trace_file,

unsigned long len)

{

struct trace_event_call *event_call = trace_file->event_call;

if ((trace_file->flags & EVENT_FILE_FL_PID_FILTER) &&

trace_event_ignore_this_pid(trace_file))

return NULL;

local_save_flags(fbuffer->flags);

fbuffer->pc = preempt_count();

/*

* If CONFIG_PREEMPT is enabled, then the tracepoint itself disables

* preemption (adding one to the preempt_count). Since we are

* interested in the preempt_count at the time the tracepoint was

* hit, we need to subtract one to offset the increment.

*/

if (IS_ENABLED(CONFIG_PREEMPT))

fbuffer->pc--;

fbuffer->trace_file = trace_file;

fbuffer->event =

trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file,

event_call->event.type, len,

fbuffer->flags, fbuffer->pc);

if (!fbuffer->event)

return NULL;

fbuffer->entry = ring_buffer_event_data(fbuffer->event);

return fbuffer->entry;

}

EXPORT_SYMBOL_GPL(trace_event_buffer_reserve);

int trace_event_reg(struct trace_event_call *call,

enum trace_reg type, void *data)

{

struct trace_event_file *file = data;

WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT));

switch (type) {

case TRACE_REG_REGISTER:

return tracepoint_probe_register(call->tp,

call->class->probe,

file);

case TRACE_REG_UNREGISTER:

tracepoint_probe_unregister(call->tp,

call->class->probe,

file);

return 0;

#ifdef CONFIG_PERF_EVENTS

case TRACE_REG_PERF_REGISTER:

return tracepoint_probe_register(call->tp,

call->class->perf_probe,

call);

case TRACE_REG_PERF_UNREGISTER:

tracepoint_probe_unregister(call->tp,

call->class->perf_probe,

call);

return 0;

case TRACE_REG_PERF_OPEN:

case TRACE_REG_PERF_CLOSE:

case TRACE_REG_PERF_ADD:

case TRACE_REG_PERF_DEL:

return 0;

#endif

}

return 0;

}

EXPORT_SYMBOL_GPL(trace_event_reg);

void trace_event_enable_cmd_record(bool enable)

{

struct trace_event_file *file;

struct trace_array *tr;

mutex_lock(&event_mutex);

do_for_each_event_file(tr, file) {

if (!(file->flags & EVENT_FILE_FL_ENABLED))

continue;

if (enable) {

tracing_start_cmdline_record();

set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);

} else {

tracing_stop_cmdline_record();

clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);

}

} while_for_each_event_file();

mutex_unlock(&event_mutex);

}

void trace_event_enable_tgid_record(bool enable)

{

struct trace_event_file *file;

struct trace_array *tr;

mutex_lock(&event_mutex);

do_for_each_event_file(tr, file) {

if (!(file->flags & EVENT_FILE_FL_ENABLED))

continue;

if (enable) {

tracing_start_tgid_record();

set_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags);

} else {

tracing_stop_tgid_record();

clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT,

&file->flags);

}

} while_for_each_event_file();

mutex_unlock(&event_mutex);

}

static int __ftrace_event_enable_disable(struct trace_event_file *file,

int enable, int soft_disable)

{

struct trace_event_call *call = file->event_call;

struct trace_array *tr = file->tr;

unsigned long file_flags = file->flags;

int ret = 0;

int disable;

switch (enable) {

case 0:

/*

* When soft_disable is set and enable is cleared, the sm_ref

* reference counter is decremented. If it reaches 0, we want

* to clear the SOFT_DISABLED flag but leave the event in the

* state that it was. That is, if the event was enabled and

* SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED

* is set we do not want the event to be enabled before we

* clear the bit.

*

* When soft_disable is not set but the SOFT_MODE flag is,

* we do nothing. Do not disable the tracepoint, otherwise

* "soft enable"s (clearing the SOFT_DISABLED bit) wont work.

*/

if (soft_disable) {

if (atomic_dec_return(&file->sm_ref) > 0)

break;

disable = file->flags & EVENT_FILE_FL_SOFT_DISABLED;

clear_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags);

} else

disable = !(file->flags & EVENT_FILE_FL_SOFT_MODE);

if (disable && (file->flags & EVENT_FILE_FL_ENABLED)) {

clear_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags);

if (file->flags & EVENT_FILE_FL_RECORDED_CMD) {

tracing_stop_cmdline_record();

clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);

}

if (file->flags & EVENT_FILE_FL_RECORDED_TGID) {

tracing_stop_tgid_record();

clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags);

}

call->class->reg(call, TRACE_REG_UNREGISTER, file);

}

/* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */

if (file->flags & EVENT_FILE_FL_SOFT_MODE)

set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);

else

clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);

break;

case 1:

/*

* When soft_disable is set and enable is set, we want to

* register the tracepoint for the event, but leave the event

* as is. That means, if the event was already enabled, we do

* nothing (but set SOFT_MODE). If the event is disabled, we

* set SOFT_DISABLED before enabling the event tracepoint, so

* it still seems to be disabled.

*/

if (!soft_disable)

clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);

else {

if (atomic_inc_return(&file->sm_ref) > 1)

break;

set_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags);

}

if (!(file->flags & EVENT_FILE_FL_ENABLED)) {

bool cmd = false, tgid = false;

/* Keep the event disabled, when going to SOFT_MODE. */

if (soft_disable)

set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);

if (tr->trace_flags & TRACE_ITER_RECORD_CMD) {

cmd = true;

tracing_start_cmdline_record();

set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);

}

if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {

tgid = true;

tracing_start_tgid_record();

set_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags);

}

ret = call->class->reg(call, TRACE_REG_REGISTER, file);

if (ret) {

if (cmd)

tracing_stop_cmdline_record();

if (tgid)

tracing_stop_tgid_record();

pr_info("event trace: Could not enable event "

"%s\n", trace_event_name(call));

break;

}

set_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags);

/* WAS_ENABLED gets set but never cleared. */

set_bit(EVENT_FILE_FL_WAS_ENABLED_BIT, &file->flags);

}

break;

}

/* Enable or disable use of trace_buffered_event */

if ((file_flags & EVENT_FILE_FL_SOFT_DISABLED) !=

(file->flags & EVENT_FILE_FL_SOFT_DISABLED)) {

if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)

trace_buffered_event_enable();

else

trace_buffered_event_disable();

}

return ret;

}

int trace_event_enable_disable(struct trace_event_file *file,

int enable, int soft_disable)

{

return __ftrace_event_enable_disable(file, enable, soft_disable);

}

static int ftrace_event_enable_disable(struct trace_event_file *file,

int enable)

{

return __ftrace_event_enable_disable(file, enable, 0);

}

static void ftrace_clear_events(struct trace_array *tr)

{

struct trace_event_file *file;

mutex_lock(&event_mutex);

list_for_each_entry(file, &tr->events, list) {

ftrace_event_enable_disable(file, 0);

}

mutex_unlock(&event_mutex);

}

static void

event_filter_pid_sched_process_exit(void *data, struct task_struct *task)

{

struct trace_pid_list *pid_list;

struct trace_array *tr = data;

pid_list = rcu_dereference_sched(tr->filtered_pids);

trace_filter_add_remove_task(pid_list, NULL, task);

}

static void

event_filter_pid_sched_process_fork(void *data,

struct task_struct *self,

struct task_struct *task)

{

struct trace_pid_list *pid_list;

struct trace_array *tr = data;

pid_list = rcu_dereference_sched(tr->filtered_pids);

trace_filter_add_remove_task(pid_list, self, task);

}

void trace_event_follow_fork(struct trace_array *tr, bool enable)

{

if (enable) {

register_trace_prio_sched_process_fork(event_filter_pid_sched_process_fork,

tr, INT_MIN);

register_trace_prio_sched_process_exit(event_filter_pid_sched_process_exit,

tr, INT_MAX);

} else {

unregister_trace_sched_process_fork(event_filter_pid_sched_process_fork,

tr);

unregister_trace_sched_process_exit(event_filter_pid_sched_process_exit,

tr);

}

}

static void

event_filter_pid_sched_switch_probe_pre(void *data, bool preempt,

struct task_struct *prev, struct task_struct *next)

{

struct trace_array *tr = data;

struct trace_pid_list *pid_list;

pid_list = rcu_dereference_sched(tr->filtered_pids);

this_cpu_write(tr->trace_buffer.data->ignore_pid,

trace_ignore_this_task(pid_list, prev) &&

trace_ignore_this_task(pid_list, next));

}

static void

event_filter_pid_sched_switch_probe_post(void *data, bool preempt,

struct task_struct *prev, struct task_struct *next)

{

struct trace_array *tr = data;

struct trace_pid_list *pid_list;

pid_list = rcu_dereference_sched(tr->filtered_pids);

this_cpu_write(tr->trace_buffer.data->ignore_pid,

trace_ignore_this_task(pid_list, next));

}

static void

event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task)

{

struct trace_array *tr = data;

struct trace_pid_list *pid_list;

/* Nothing to do if we are already tracing */

if (!this_cpu_read(tr->trace_buffer.data->ignore_pid))

return;

pid_list = rcu_dereference_sched(tr->filtered_pids);

this_cpu_write(tr->trace_buffer.data->ignore_pid,

trace_ignore_this_task(pid_list, task));

}

static void

event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task)

{

struct trace_array *tr = data;

struct trace_pid_list *pid_list;

/* Nothing to do if we are not tracing */

if (this_cpu_read(tr->trace_buffer.data->ignore_pid))

return;

pid_list = rcu_dereference_sched(tr->filtered_pids);

/* Set tracing if current is enabled */

this_cpu_write(tr->trace_buffer.data->ignore_pid,

trace_ignore_this_task(pid_list, current));

}

static void __ftrace_clear_event_pids(struct trace_array *tr)

{

struct trace_pid_list *pid_list;

struct trace_event_file *file;

int cpu;

pid_list = rcu_dereference_protected(tr->filtered_pids,

lockdep_is_held(&event_mutex));

if (!pid_list)

return;

unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr);

unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr);

unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr);

unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr);

unregister_trace_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_pre, tr);

unregister_trace_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_post, tr);

unregister_trace_sched_waking(event_filter_pid_sched_wakeup_probe_pre, tr);

unregister_trace_sched_waking(event_filter_pid_sched_wakeup_probe_post, tr);

list_for_each_entry(file, &tr->events, list) {

clear_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags);

}

for_each_possible_cpu(cpu)

per_cpu_ptr(tr->trace_buffer.data, cpu)->ignore_pid = false;

rcu_assign_pointer(tr->filtered_pids, NULL);

/* Wait till all users are no longer using pid filtering */

synchronize_sched();

trace_free_pid_list(pid_list);

}

static void ftrace_clear_event_pids(struct trace_array *tr)

{

mutex_lock(&event_mutex);

__ftrace_clear_event_pids(tr);

mutex_unlock(&event_mutex);

}

static void __put_system(struct event_subsystem *system)

{

struct event_filter *filter = system->filter;

WARN_ON_ONCE(system_refcount(system) == 0);

if (system_refcount_dec(system))

return;

list_del(&system->list);

if (filter) {

kfree(filter->filter_string);

kfree(filter);

}

kfree_const(system->name);

kfree(system);

}

static void __get_system(struct event_subsystem *system)

{

WARN_ON_ONCE(system_refcount(system) == 0);

system_refcount_inc(system);

}

static void __get_system_dir(struct trace_subsystem_dir *dir)

{

WARN_ON_ONCE(dir->ref_count == 0);

dir->ref_count++;

__get_system(dir->subsystem);

}

static void __put_system_dir(struct trace_subsystem_dir *dir)

{

WARN_ON_ONCE(dir->ref_count == 0);

/* If the subsystem is about to be freed, the dir must be too */

WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1);

__put_system(dir->subsystem);

if (!--dir->ref_count)

kfree(dir);

}

static void put_system(struct trace_subsystem_dir *dir)

{

mutex_lock(&event_mutex);

__put_system_dir(dir);

mutex_unlock(&event_mutex);

}

static void remove_subsystem(struct trace_subsystem_dir *dir)

{

if (!dir)

return;

if (!--dir->nr_events) {

tracefs_remove_recursive(dir->entry);

list_del(&dir->list);

__put_system_dir(dir);

}

}

static void remove_event_file_dir(struct trace_event_file *file)

{

struct dentry *dir = file->dir;

struct dentry *child;

if (dir) {

spin_lock(&dir->d_lock); /* probably unneeded */

list_for_each_entry(child, &dir->d_subdirs, d_child) {

if (d_really_is_positive(child)) /* probably unneeded */

d_inode(child)->i_private = NULL;

}

spin_unlock(&dir->d_lock);

tracefs_remove_recursive(dir);

}

list_del(&file->list);

remove_subsystem(file->system);

free_event_filter(file->filter);

kmem_cache_free(file_cachep, file);

}

/*

* __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.

*/

static int

__ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match,

const char *sub, const char *event, int set)

{

struct trace_event_file *file;

struct trace_event_call *call;

const char *name;

int ret = -EINVAL;

int eret = 0;

list_for_each_entry(file, &tr->events, list) {

call = file->event_call;

name = trace_event_name(call);

if (!name || !call->class || !call->class->reg)

continue;

if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)

continue;

if (match &&

strcmp(match, name) != 0 &&

strcmp(match, call->class->system) != 0)

continue;

if (sub && strcmp(sub, call->class->system) != 0)

continue;

if (event && strcmp(event, name) != 0)

continue;

ret = ftrace_event_enable_disable(file, set);

/*

* Save the first error and return that. Some events

* may still have been enabled, but let the user

* know that something went wrong.

*/

if (ret && !eret)

eret = ret;

ret = eret;

}

return ret;

}

static int __ftrace_set_clr_event(struct trace_array *tr, const char *match,

const char *sub, const char *event, int set)

{

int ret;

mutex_lock(&event_mutex);

ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set);

mutex_unlock(&event_mutex);

return ret;

}

static int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)

{

char *event = NULL, *sub = NULL, *match;

int ret;

/*

* The buf format can be <subsystem>:<event-name>

* *:<event-name> means any event by that name.

* :<event-name> is the same.

*

* <subsystem>:* means all events in that subsystem

* <subsystem>: means the same.

*

* <name> (no ':') means all events in a subsystem with

* the name <name> or any event that matches <name>

*/

match = strsep(&buf, ":");

if (buf) {

sub = match;

event = buf;

match = NULL;

if (!strlen(sub) || strcmp(sub, "*") == 0)

sub = NULL;

if (!strlen(event) || strcmp(event, "*") == 0)

event = NULL;

}

ret = __ftrace_set_clr_event(tr, match, sub, event, set);

/* Put back the colon to allow this to be called again */

if (buf)

*(buf - 1) = ':';

return ret;

}

/**

* trace_set_clr_event - enable or disable an event

* @system: system name to match (NULL for any system)

* @event: event name to match (NULL for all events, within system)

* @set: 1 to enable, 0 to disable

*

* This is a way for other parts of the kernel to enable or disable

* event recording.

*

* Returns 0 on success, -EINVAL if the parameters do not match any

* registered events.

*/

int trace_set_clr_event(const char *system, const char *event, int set)

{

struct trace_array *tr = top_trace_array();

if (!tr)

return -ENODEV;

return __ftrace_set_clr_event(tr, NULL, system, event, set);

}

EXPORT_SYMBOL_GPL(trace_set_clr_event);

/* 128 should be much more than enough */

#define EVENT_BUF_SIZE 127

static ssize_t

ftrace_event_write(struct file *file, const char __user *ubuf,

size_t cnt, loff_t *ppos)

{

struct trace_parser parser;

struct seq_file *m = file->private_data;

struct trace_array *tr = m->private;

ssize_t read, ret;

if (!cnt)

return 0;

ret = tracing_update_buffers();

if (ret < 0)

return ret;

if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))

return -ENOMEM;

read = trace_get_user(&parser, ubuf, cnt, ppos);

if (read >= 0 && trace_parser_loaded((&parser))) {

int set = 1;

if (*parser.buffer == '!')

set = 0;

parser.buffer[parser.idx] = 0;

ret = ftrace_set_clr_event(tr, parser.buffer + !set, set);

if (ret)

goto out_put;

}

ret = read;

out_put:

trace_parser_put(&parser);

return ret;

}

static void *

t_next(struct seq_file *m, void *v, loff_t *pos)

{

struct trace_event_file *file = v;

struct trace_event_call *call;

struct trace_array *tr = m->private;

(*pos)++;

list_for_each_entry_continue(file, &tr->events, list) {

call = file->event_call;

/*

* The ftrace subsystem is for showing formats only.

* They can not be enabled or disabled via the event files.

*/

if (call->class && call->class->reg &&

!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))

return file;

}

return NULL;

}

static void *t_start(struct seq_file *m, loff_t *pos)

{

struct trace_event_file *file;

struct trace_array *tr = m->private;

loff_t l;

mutex_lock(&event_mutex);

file = list_entry(&tr->events, struct trace_event_file, list);

for (l = 0; l <= *pos; ) {

file = t_next(m, file, &l);

if (!file)

break;

}

return file;

}

static void *

s_next(struct seq_file *m, void *v, loff_t *pos)

{

struct trace_event_file *file = v;

struct trace_array *tr = m->private;

(*pos)++;

list_for_each_entry_continue(file, &tr->events, list) {

if (file->flags & EVENT_FILE_FL_ENABLED)

return file;

}

return NULL;

}

static void *s_start(struct seq_file *m, loff_t *pos)

{

struct trace_event_file *file;

struct trace_array *tr = m->private;

loff_t l;

mutex_lock(&event_mutex);

file = list_entry(&tr->events, struct trace_event_file, list);

for (l = 0; l <= *pos; ) {

file = s_next(m, file, &l);

if (!file)

break;

}

return file;

}

static int t_show(struct seq_file *m, void *v)

{

struct trace_event_file *file = v;

struct trace_event_call *call = file->event_call;

if (strcmp(call->class->system, TRACE_SYSTEM) != 0)

seq_printf(m, "%s:", call->class->system);

seq_printf(m, "%s\n", trace_event_name(call));

return 0;

}

static void t_stop(struct seq_file *m, void *p)

{

mutex_unlock(&event_mutex);

}

static void *

p_next(struct seq_file *m, void *v, loff_t *pos)

{

struct trace_array *tr = m->private;

struct trace_pid_list *pid_list = rcu_dereference_sched(tr->filtered_pids);

return trace_pid_next(pid_list, v, pos);

}