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-rw-r--r--kernel/trace/trace_events.c4173
1 files changed, 4173 insertions, 0 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
new file mode 100644
index 0000000000..82cb22ad6d
--- /dev/null
+++ b/kernel/trace/trace_events.c
@@ -0,0 +1,4173 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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/security.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 <trace/syscall.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);
+static bool eventdir_initialized;
+
+static LIST_HEAD(module_strings);
+
+struct module_string {
+ struct list_head next;
+ struct module *module;
+ char *str;
+};
+
+#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 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, int len)
+{
+ 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;
+ field->len = len;
+
+ 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, 0);
+}
+EXPORT_SYMBOL_GPL(trace_define_field);
+
+static int trace_define_field_ext(struct trace_event_call *call, const char *type,
+ const char *name, int offset, int size, int is_signed,
+ int filter_type, int len)
+{
+ 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, len);
+}
+
+#define __generic_field(type, item, filter_type) \
+ ret = __trace_define_field(&ftrace_generic_fields, #type, \
+ #item, 0, 0, is_signed_type(type), \
+ filter_type, 0); \
+ 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, 0); \
+ 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(int, common_cpu, FILTER_CPU);
+ __generic_field(char *, COMM, FILTER_COMM);
+ __generic_field(char *, comm, FILTER_COMM);
+ __generic_field(char *, stacktrace, FILTER_STACKTRACE);
+ __generic_field(char *, STACKTRACE, FILTER_STACKTRACE);
+
+ 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);
+ /* Holds both preempt_count and migrate_disable */
+ __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;
+}
+
+/*
+ * Check if the referenced field is an array and return true,
+ * as arrays are OK to dereference.
+ */
+static bool test_field(const char *fmt, struct trace_event_call *call)
+{
+ struct trace_event_fields *field = call->class->fields_array;
+ const char *array_descriptor;
+ const char *p = fmt;
+ int len;
+
+ if (!(len = str_has_prefix(fmt, "REC->")))
+ return false;
+ fmt += len;
+ for (p = fmt; *p; p++) {
+ if (!isalnum(*p) && *p != '_')
+ break;
+ }
+ len = p - fmt;
+
+ for (; field->type; field++) {
+ if (strncmp(field->name, fmt, len) ||
+ field->name[len])
+ continue;
+ array_descriptor = strchr(field->type, '[');
+ /* This is an array and is OK to dereference. */
+ return array_descriptor != NULL;
+ }
+ return false;
+}
+
+/*
+ * Examine the print fmt of the event looking for unsafe dereference
+ * pointers using %p* that could be recorded in the trace event and
+ * much later referenced after the pointer was freed. Dereferencing
+ * pointers are OK, if it is dereferenced into the event itself.
+ */
+static void test_event_printk(struct trace_event_call *call)
+{
+ u64 dereference_flags = 0;
+ bool first = true;
+ const char *fmt, *c, *r, *a;
+ int parens = 0;
+ char in_quote = 0;
+ int start_arg = 0;
+ int arg = 0;
+ int i;
+
+ fmt = call->print_fmt;
+
+ if (!fmt)
+ return;
+
+ for (i = 0; fmt[i]; i++) {
+ switch (fmt[i]) {
+ case '\\':
+ i++;
+ if (!fmt[i])
+ return;
+ continue;
+ case '"':
+ case '\'':
+ /*
+ * The print fmt starts with a string that
+ * is processed first to find %p* usage,
+ * then after the first string, the print fmt
+ * contains arguments that are used to check
+ * if the dereferenced %p* usage is safe.
+ */
+ if (first) {
+ if (fmt[i] == '\'')
+ continue;
+ if (in_quote) {
+ arg = 0;
+ first = false;
+ /*
+ * If there was no %p* uses
+ * the fmt is OK.
+ */
+ if (!dereference_flags)
+ return;
+ }
+ }
+ if (in_quote) {
+ if (in_quote == fmt[i])
+ in_quote = 0;
+ } else {
+ in_quote = fmt[i];
+ }
+ continue;
+ case '%':
+ if (!first || !in_quote)
+ continue;
+ i++;
+ if (!fmt[i])
+ return;
+ switch (fmt[i]) {
+ case '%':
+ continue;
+ case 'p':
+ /* Find dereferencing fields */
+ switch (fmt[i + 1]) {
+ case 'B': case 'R': case 'r':
+ case 'b': case 'M': case 'm':
+ case 'I': case 'i': case 'E':
+ case 'U': case 'V': case 'N':
+ case 'a': case 'd': case 'D':
+ case 'g': case 't': case 'C':
+ case 'O': case 'f':
+ if (WARN_ONCE(arg == 63,
+ "Too many args for event: %s",
+ trace_event_name(call)))
+ return;
+ dereference_flags |= 1ULL << arg;
+ }
+ break;
+ default:
+ {
+ bool star = false;
+ int j;
+
+ /* Increment arg if %*s exists. */
+ for (j = 0; fmt[i + j]; j++) {
+ if (isdigit(fmt[i + j]) ||
+ fmt[i + j] == '.')
+ continue;
+ if (fmt[i + j] == '*') {
+ star = true;
+ continue;
+ }
+ if ((fmt[i + j] == 's') && star)
+ arg++;
+ break;
+ }
+ break;
+ } /* default */
+
+ } /* switch */
+ arg++;
+ continue;
+ case '(':
+ if (in_quote)
+ continue;
+ parens++;
+ continue;
+ case ')':
+ if (in_quote)
+ continue;
+ parens--;
+ if (WARN_ONCE(parens < 0,
+ "Paren mismatch for event: %s\narg='%s'\n%*s",
+ trace_event_name(call),
+ fmt + start_arg,
+ (i - start_arg) + 5, "^"))
+ return;
+ continue;
+ case ',':
+ if (in_quote || parens)
+ continue;
+ i++;
+ while (isspace(fmt[i]))
+ i++;
+ start_arg = i;
+ if (!(dereference_flags & (1ULL << arg)))
+ goto next_arg;
+
+ /* Find the REC-> in the argument */
+ c = strchr(fmt + i, ',');
+ r = strstr(fmt + i, "REC->");
+ if (r && (!c || r < c)) {
+ /*
+ * Addresses of events on the buffer,
+ * or an array on the buffer is
+ * OK to dereference.
+ * There's ways to fool this, but
+ * this is to catch common mistakes,
+ * not malicious code.
+ */
+ a = strchr(fmt + i, '&');
+ if ((a && (a < r)) || test_field(r, call))
+ dereference_flags &= ~(1ULL << arg);
+ } else if ((r = strstr(fmt + i, "__get_dynamic_array(")) &&
+ (!c || r < c)) {
+ dereference_flags &= ~(1ULL << arg);
+ } else if ((r = strstr(fmt + i, "__get_sockaddr(")) &&
+ (!c || r < c)) {
+ dereference_flags &= ~(1ULL << arg);
+ }
+
+ next_arg:
+ i--;
+ arg++;
+ }
+ }
+
+ /*
+ * If you triggered the below warning, the trace event reported
+ * uses an unsafe dereference pointer %p*. As the data stored
+ * at the trace event time may no longer exist when the trace
+ * event is printed, dereferencing to the original source is
+ * unsafe. The source of the dereference must be copied into the
+ * event itself, and the dereference must access the copy instead.
+ */
+ if (WARN_ON_ONCE(dereference_flags)) {
+ arg = 1;
+ while (!(dereference_flags & 1)) {
+ dereference_flags >>= 1;
+ arg++;
+ }
+ pr_warn("event %s has unsafe dereference of argument %d\n",
+ trace_event_name(call), arg);
+ pr_warn("print_fmt: %s\n", fmt);
+ }
+}
+
+int trace_event_raw_init(struct trace_event_call *call)
+{
+ int id;
+
+ id = register_trace_event(&call->event);
+ if (!id)
+ return -ENODEV;
+
+ test_event_printk(call);
+
+ 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 *no_pid_list;
+ struct trace_pid_list *pid_list;
+
+ pid_list = rcu_dereference_raw(tr->filtered_pids);
+ no_pid_list = rcu_dereference_raw(tr->filtered_no_pids);
+
+ if (!pid_list && !no_pid_list)
+ return false;
+
+ data = this_cpu_ptr(tr->array_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;
+
+ /*
+ * If CONFIG_PREEMPTION 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.
+ */
+ fbuffer->trace_ctx = tracing_gen_ctx_dec();
+ fbuffer->trace_file = trace_file;
+
+ fbuffer->event =
+ trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file,
+ event_call->event.type, len,
+ fbuffer->trace_ctx);
+ if (!fbuffer->event)
+ return NULL;
+
+ fbuffer->regs = 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;
+
+ lockdep_assert_held(&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();
+}
+
+void trace_event_enable_tgid_record(bool enable)
+{
+ struct trace_event_file *file;
+ struct trace_array *tr;
+
+ lockdep_assert_held(&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();
+}
+
+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;
+ 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);
+ /* Disable use of trace_buffered_event */
+ trace_buffered_event_disable();
+ } 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);
+ /* Enable use of trace_buffered_event */
+ trace_buffered_event_enable();
+ }
+
+ 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;
+ }
+
+ 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_raw(tr->filtered_pids);
+ trace_filter_add_remove_task(pid_list, NULL, task);
+
+ pid_list = rcu_dereference_raw(tr->filtered_no_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);
+
+ pid_list = rcu_dereference_sched(tr->filtered_no_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_free(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_free(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,
+ unsigned int prev_state)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *no_pid_list;
+ struct trace_pid_list *pid_list;
+ bool ret;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ no_pid_list = rcu_dereference_sched(tr->filtered_no_pids);
+
+ /*
+ * Sched switch is funny, as we only want to ignore it
+ * in the notrace case if both prev and next should be ignored.
+ */
+ ret = trace_ignore_this_task(NULL, no_pid_list, prev) &&
+ trace_ignore_this_task(NULL, no_pid_list, next);
+
+ this_cpu_write(tr->array_buffer.data->ignore_pid, ret ||
+ (trace_ignore_this_task(pid_list, NULL, prev) &&
+ trace_ignore_this_task(pid_list, NULL, next)));
+}
+
+static void
+event_filter_pid_sched_switch_probe_post(void *data, bool preempt,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned int prev_state)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *no_pid_list;
+ struct trace_pid_list *pid_list;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ no_pid_list = rcu_dereference_sched(tr->filtered_no_pids);
+
+ this_cpu_write(tr->array_buffer.data->ignore_pid,
+ trace_ignore_this_task(pid_list, no_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 *no_pid_list;
+ struct trace_pid_list *pid_list;
+
+ /* Nothing to do if we are already tracing */
+ if (!this_cpu_read(tr->array_buffer.data->ignore_pid))
+ return;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ no_pid_list = rcu_dereference_sched(tr->filtered_no_pids);
+
+ this_cpu_write(tr->array_buffer.data->ignore_pid,
+ trace_ignore_this_task(pid_list, no_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 *no_pid_list;
+ struct trace_pid_list *pid_list;
+
+ /* Nothing to do if we are not tracing */
+ if (this_cpu_read(tr->array_buffer.data->ignore_pid))
+ return;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ no_pid_list = rcu_dereference_sched(tr->filtered_no_pids);
+
+ /* Set tracing if current is enabled */
+ this_cpu_write(tr->array_buffer.data->ignore_pid,
+ trace_ignore_this_task(pid_list, no_pid_list, current));
+}
+
+static void unregister_pid_events(struct trace_array *tr)
+{
+ 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);
+}
+
+static void __ftrace_clear_event_pids(struct trace_array *tr, int type)
+{
+ struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
+ struct trace_event_file *file;
+ int cpu;
+
+ pid_list = rcu_dereference_protected(tr->filtered_pids,
+ lockdep_is_held(&event_mutex));
+ no_pid_list = rcu_dereference_protected(tr->filtered_no_pids,
+ lockdep_is_held(&event_mutex));
+
+ /* Make sure there's something to do */
+ if (!pid_type_enabled(type, pid_list, no_pid_list))
+ return;
+
+ if (!still_need_pid_events(type, pid_list, no_pid_list)) {
+ unregister_pid_events(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->array_buffer.data, cpu)->ignore_pid = false;
+ }
+
+ if (type & TRACE_PIDS)
+ rcu_assign_pointer(tr->filtered_pids, NULL);
+
+ if (type & TRACE_NO_PIDS)
+ rcu_assign_pointer(tr->filtered_no_pids, NULL);
+
+ /* Wait till all users are no longer using pid filtering */
+ tracepoint_synchronize_unregister();
+
+ if ((type & TRACE_PIDS) && pid_list)
+ trace_pid_list_free(pid_list);
+
+ if ((type & TRACE_NO_PIDS) && no_pid_list)
+ trace_pid_list_free(no_pid_list);
+}
+
+static void ftrace_clear_event_pids(struct trace_array *tr, int type)
+{
+ mutex_lock(&event_mutex);
+ __ftrace_clear_event_pids(tr, type);
+ 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) {
+ eventfs_remove(dir->ef);
+ list_del(&dir->list);
+ __put_system_dir(dir);
+ }
+}
+
+void event_file_get(struct trace_event_file *file)
+{
+ atomic_inc(&file->ref);
+}
+
+void event_file_put(struct trace_event_file *file)
+{
+ if (WARN_ON_ONCE(!atomic_read(&file->ref))) {
+ if (file->flags & EVENT_FILE_FL_FREED)
+ kmem_cache_free(file_cachep, file);
+ return;
+ }
+
+ if (atomic_dec_and_test(&file->ref)) {
+ /* Count should only go to zero when it is freed */
+ if (WARN_ON_ONCE(!(file->flags & EVENT_FILE_FL_FREED)))
+ return;
+ kmem_cache_free(file_cachep, file);
+ }
+}
+
+static void remove_event_file_dir(struct trace_event_file *file)
+{
+ eventfs_remove(file->ef);
+ list_del(&file->list);
+ remove_subsystem(file->system);
+ free_event_filter(file->filter);
+ file->flags |= EVENT_FILE_FL_FREED;
+ event_file_put(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;
+}
+
+int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set)
+{
+ char *event = NULL, *sub = NULL, *match;
+ int ret;
+
+ if (!tr)
+ return -ENOENT;
+ /*
+ * 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);
+
+/**
+ * trace_array_set_clr_event - enable or disable an event for a trace array.
+ * @tr: concerned trace array.
+ * @system: system name to match (NULL for any system)
+ * @event: event name to match (NULL for all events, within system)
+ * @enable: true to enable, false 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_array_set_clr_event(struct trace_array *tr, const char *system,
+ const char *event, bool enable)
+{
+ int set;
+
+ if (!tr)
+ return -ENOENT;
+
+ set = (enable == true) ? 1 : 0;
+ return __ftrace_set_clr_event(tr, NULL, system, event, set);
+}
+EXPORT_SYMBOL_GPL(trace_array_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;
+
+ 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 *
+__next(struct seq_file *m, void *v, loff_t *pos, int type)
+{
+ struct trace_array *tr = m->private;
+ struct trace_pid_list *pid_list;
+
+ if (type == TRACE_PIDS)
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ else
+ pid_list = rcu_dereference_sched(tr->filtered_no_pids);
+
+ return trace_pid_next(pid_list, v, pos);
+}
+
+static void *
+p_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return __next(m, v, pos, TRACE_PIDS);
+}
+
+static void *
+np_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return __next(m, v, pos, TRACE_NO_PIDS);
+}
+
+static void *__start(struct seq_file *m, loff_t *pos, int type)
+ __acquires(RCU)
+{
+ struct trace_pid_list *pid_list;
+ struct trace_array *tr = m->private;
+
+ /*
+ * Grab the mutex, to keep calls to p_next() having the same
+ * tr->filtered_pids as p_start() has.
+ * If we just passed the tr->filtered_pids around, then RCU would
+ * have been enough, but doing that makes things more complex.
+ */
+ mutex_lock(&event_mutex);
+ rcu_read_lock_sched();
+
+ if (type == TRACE_PIDS)
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ else
+ pid_list = rcu_dereference_sched(tr->filtered_no_pids);
+
+ if (!pid_list)
+ return NULL;
+
+ return trace_pid_start(pid_list, pos);
+}
+
+static void *p_start(struct seq_file *m, loff_t *pos)
+ __acquires(RCU)
+{
+ return __start(m, pos, TRACE_PIDS);
+}
+
+static void *np_start(struct seq_file *m, loff_t *pos)
+ __acquires(RCU)
+{
+ return __start(m, pos, TRACE_NO_PIDS);
+}
+
+static void p_stop(struct seq_file *m, void *p)
+ __releases(RCU)
+{
+ rcu_read_unlock_sched();
+ mutex_unlock(&event_mutex);
+}
+
+static ssize_t
+event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_event_file *file;
+ unsigned long flags;
+ char buf[4] = "0";
+
+ mutex_lock(&event_mutex);
+ file = event_file_data(filp);
+ if (likely(file))
+ flags = file->flags;
+ mutex_unlock(&event_mutex);
+
+ if (!file || flags & EVENT_FILE_FL_FREED)
+ return -ENODEV;
+
+ if (flags & EVENT_FILE_FL_ENABLED &&
+ !(flags & EVENT_FILE_FL_SOFT_DISABLED))
+ strcpy(buf, "1");
+
+ if (flags & EVENT_FILE_FL_SOFT_DISABLED ||
+ flags & EVENT_FILE_FL_SOFT_MODE)
+ strcat(buf, "*");
+
+ strcat(buf, "\n");
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf));
+}
+
+static ssize_t
+event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_event_file *file;
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ ret = tracing_update_buffers();
+ if (ret < 0)
+ return ret;
+
+ switch (val) {
+ case 0:
+ case 1:
+ ret = -ENODEV;
+ mutex_lock(&event_mutex);
+ file = event_file_data(filp);
+ if (likely(file && !(file->flags & EVENT_FILE_FL_FREED)))
+ ret = ftrace_event_enable_disable(file, val);
+ mutex_unlock(&event_mutex);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ *ppos += cnt;
+
+ return ret ? ret : cnt;
+}
+
+static ssize_t
+system_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ const char set_to_char[4] = { '?', '0', '1', 'X' };
+ struct trace_subsystem_dir *dir = filp->private_data;
+ struct event_subsystem *system = dir->subsystem;
+ struct trace_event_call *call;
+ struct trace_event_file *file;
+ struct trace_array *tr = dir->tr;
+ char buf[2];
+ int set = 0;
+ int ret;
+
+ mutex_lock(&event_mutex);
+ list_for_each_entry(file, &tr->events, list) {
+ call = file->event_call;
+ if ((call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) ||
+ !trace_event_name(call) || !call->class || !call->class->reg)
+ continue;
+
+ if (system && strcmp(call->class->system, system->name) != 0)
+ continue;
+
+ /*
+ * We need to find out if all the events are set
+ * or if all events or cleared, or if we have
+ * a mixture.
+ */
+ set |= (1 << !!(file->flags & EVENT_FILE_FL_ENABLED));
+
+ /*
+ * If we have a mixture, no need to look further.
+ */
+ if (set == 3)
+ break;
+ }
+ mutex_unlock(&event_mutex);
+
+ buf[0] = set_to_char[set];
+ buf[1] = '\n';
+
+ ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
+
+ return ret;
+}
+
+static ssize_t
+system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_subsystem_dir *dir = filp->private_data;
+ struct event_subsystem *system = dir->subsystem;
+ const char *name = NULL;
+ unsigned long val;
+ ssize_t ret;
+
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
+ return ret;
+
+ ret = tracing_update_buffers();
+ if (ret < 0)
+ return ret;
+
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ /*
+ * Opening of "enable" adds a ref count to system,
+ * so the name is safe to use.
+ */
+ if (system)
+ name = system->name;
+
+ ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val);
+ if (ret)
+ goto out;
+
+ ret = cnt;
+
+out:
+ *ppos += cnt;
+
+ return ret;
+}
+
+enum {
+ FORMAT_HEADER = 1,
+ FORMAT_FIELD_SEPERATOR = 2,
+ FORMAT_PRINTFMT = 3,
+};
+
+static void *f_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct trace_event_call *call = event_file_data(m->private);
+ struct list_head *common_head = &ftrace_common_fields;
+ struct list_head *head = trace_get_fields(call);
+ struct list_head *node = v;
+
+ (*pos)++;
+
+ switch ((unsigned long)v) {
+ case FORMAT_HEADER:
+ node = common_head;
+ break;
+
+ case FORMAT_FIELD_SEPERATOR:
+ node = head;
+ break;
+
+ case FORMAT_PRINTFMT:
+ /* all done */
+ return NULL;
+ }
+
+ node = node->prev;
+ if (node == common_head)
+ return (void *)FORMAT_FIELD_SEPERATOR;
+ else if (node == head)
+ return (void *)FORMAT_PRINTFMT;
+ else
+ return node;
+}
+
+static int f_show(struct seq_file *m, void *v)
+{
+ struct trace_event_call *call = event_file_data(m->private);
+ struct ftrace_event_field *field;
+ const char *array_descriptor;
+
+ switch ((unsigned long)v) {
+ case FORMAT_HEADER:
+ seq_printf(m, "name: %s\n", trace_event_name(call));
+ seq_printf(m, "ID: %d\n", call->event.type);
+ seq_puts(m, "format:\n");
+ return 0;
+
+ case FORMAT_FIELD_SEPERATOR:
+ seq_putc(m, '\n');
+ return 0;
+
+ case FORMAT_PRINTFMT:
+ seq_printf(m, "\nprint fmt: %s\n",
+ call->print_fmt);
+ return 0;
+ }
+
+ field = list_entry(v, struct ftrace_event_field, link);
+ /*
+ * Smartly shows the array type(except dynamic array).
+ * Normal:
+ * field:TYPE VAR
+ * If TYPE := TYPE[LEN], it is shown:
+ * field:TYPE VAR[LEN]
+ */
+ array_descriptor = strchr(field->type, '[');
+
+ if (str_has_prefix(field->type, "__data_loc"))
+ array_descriptor = NULL;
+
+ if (!array_descriptor)
+ seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
+ field->type, field->name, field->offset,
+ field->size, !!field->is_signed);
+ else if (field->len)
+ seq_printf(m, "\tfield:%.*s %s[%d];\toffset:%u;\tsize:%u;\tsigned:%d;\n",
+ (int)(array_descriptor - field->type),
+ field->type, field->name,
+ field->len, field->offset,
+ field->size, !!field->is_signed);
+ else
+ seq_printf(m, "\tfield:%.*s %s[];\toffset:%u;\tsize:%u;\tsigned:%d;\n",
+ (int)(array_descriptor - field->type),
+ field->type, field->name,
+ field->offset, field->size, !!field->is_signed);
+
+ return 0;
+}
+
+static void *f_start(struct seq_file *m, loff_t *pos)
+{
+ void *p = (void *)FORMAT_HEADER;
+ loff_t l = 0;
+
+ /* ->stop() is called even if ->start() fails */
+ mutex_lock(&event_mutex);
+ if (!event_file_data(m->private))
+ return ERR_PTR(-ENODEV);
+
+ while (l < *pos && p)
+ p = f_next(m, p, &l);
+
+ return p;
+}
+
+static void f_stop(struct seq_file *m, void *p)
+{
+ mutex_unlock(&event_mutex);
+}
+
+static const struct seq_operations trace_format_seq_ops = {
+ .start = f_start,
+ .next = f_next,
+ .stop = f_stop,
+ .show = f_show,
+};
+
+static int trace_format_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *m;
+ int ret;
+
+ /* Do we want to hide event format files on tracefs lockdown? */
+
+ ret = seq_open(file, &trace_format_seq_ops);
+ if (ret < 0)
+ return ret;
+
+ m = file->private_data;
+ m->private = file;
+
+ return 0;
+}
+
+static ssize_t
+event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+ int id = (long)event_file_data(filp);
+ char buf[32];
+ int len;
+
+ if (unlikely(!id))
+ return -ENODEV;
+
+ len = sprintf(buf, "%d\n", id);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
+}
+
+static ssize_t
+event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_event_file *file;
+ struct trace_seq *s;
+ int r = -ENODEV;
+
+ if (*ppos)
+ return 0;
+
+ s = kmalloc(sizeof(*s), GFP_KERNEL);
+
+ if (!s)
+ return -ENOMEM;
+
+ trace_seq_init(s);
+
+ mutex_lock(&event_mutex);
+ file = event_file_data(filp);
+ if (file && !(file->flags & EVENT_FILE_FL_FREED))
+ print_event_filter(file, s);
+ mutex_unlock(&event_mutex);
+
+ if (file)
+ r = simple_read_from_buffer(ubuf, cnt, ppos,
+ s->buffer, trace_seq_used(s));
+
+ kfree(s);
+
+ return r;
+}
+
+static ssize_t
+event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_event_file *file;
+ char *buf;
+ int err = -ENODEV;
+
+ if (cnt >= PAGE_SIZE)
+ return -EINVAL;
+
+ buf = memdup_user_nul(ubuf, cnt);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+
+ mutex_lock(&event_mutex);
+ file = event_file_data(filp);
+ if (file)
+ err = apply_event_filter(file, buf);
+ mutex_unlock(&event_mutex);
+
+ kfree(buf);
+ if (err < 0)
+ return err;
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static LIST_HEAD(event_subsystems);
+
+static int subsystem_open(struct inode *inode, struct file *filp)
+{
+ struct trace_subsystem_dir *dir = NULL, *iter_dir;
+ struct trace_array *tr = NULL, *iter_tr;
+ struct event_subsystem *system = NULL;
+ int ret;
+
+ if (tracing_is_disabled())
+ return -ENODEV;
+
+ /* Make sure the system still exists */
+ mutex_lock(&event_mutex);
+ mutex_lock(&trace_types_lock);
+ list_for_each_entry(iter_tr, &ftrace_trace_arrays, list) {
+ list_for_each_entry(iter_dir, &iter_tr->systems, list) {
+ if (iter_dir == inode->i_private) {
+ /* Don't open systems with no events */
+ tr = iter_tr;
+ dir = iter_dir;
+ if (dir->nr_events) {
+ __get_system_dir(dir);
+ system = dir->subsystem;
+ }
+ goto exit_loop;
+ }
+ }
+ }
+ exit_loop:
+ mutex_unlock(&trace_types_lock);
+ mutex_unlock(&event_mutex);
+
+ if (!system)
+ return -ENODEV;
+
+ /* Still need to increment the ref count of the system */
+ if (trace_array_get(tr) < 0) {
+ put_system(dir);
+ return -ENODEV;
+ }
+
+ ret = tracing_open_generic(inode, filp);
+ if (ret < 0) {
+ trace_array_put(tr);
+ put_system(dir);
+ }
+
+ return ret;
+}
+
+static int system_tr_open(struct inode *inode, struct file *filp)
+{
+ struct trace_subsystem_dir *dir;
+ struct trace_array *tr = inode->i_private;
+ int ret;
+
+ /* Make a temporary dir that has no system but points to tr */
+ dir = kzalloc(sizeof(*dir), GFP_KERNEL);
+ if (!dir)
+ return -ENOMEM;
+
+ ret = tracing_open_generic_tr(inode, filp);
+ if (ret < 0) {
+ kfree(dir);
+ return ret;
+ }
+ dir->tr = tr;
+ filp->private_data = dir;
+
+ return 0;
+}
+
+static int subsystem_release(struct inode *inode, struct file *file)
+{
+ struct trace_subsystem_dir *dir = file->private_data;
+
+ trace_array_put(dir->tr);
+
+ /*
+ * If dir->subsystem is NULL, then this is a temporary
+ * descriptor that was made for a trace_array to enable
+ * all subsystems.
+ */
+ if (dir->subsystem)
+ put_system(dir);
+ else
+ kfree(dir);
+
+ return 0;
+}
+
+static ssize_t
+subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_subsystem_dir *dir = filp->private_data;
+ struct event_subsystem *system = dir->subsystem;
+ struct trace_seq *s;
+ int r;
+
+ if (*ppos)
+ return 0;
+
+ s = kmalloc(sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return -ENOMEM;
+
+ trace_seq_init(s);
+
+ print_subsystem_event_filter(system, s);
+ r = simple_read_from_buffer(ubuf, cnt, ppos,
+ s->buffer, trace_seq_used(s));
+
+ kfree(s);
+
+ return r;
+}
+
+static ssize_t
+subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_subsystem_dir *dir = filp->private_data;
+ char *buf;
+ int err;
+
+ if (cnt >= PAGE_SIZE)
+ return -EINVAL;
+
+ buf = memdup_user_nul(ubuf, cnt);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+
+ err = apply_subsystem_event_filter(dir, buf);
+ kfree(buf);
+ if (err < 0)
+ return err;
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static ssize_t
+show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+ int (*func)(struct trace_seq *s) = filp->private_data;
+ struct trace_seq *s;
+ int r;
+
+ if (*ppos)
+ return 0;
+
+ s = kmalloc(sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return -ENOMEM;
+
+ trace_seq_init(s);
+
+ func(s);
+ r = simple_read_from_buffer(ubuf, cnt, ppos,
+ s->buffer, trace_seq_used(s));
+
+ kfree(s);
+
+ return r;
+}
+
+static void ignore_task_cpu(void *data)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
+
+ /*
+ * This function is called by on_each_cpu() while the
+ * event_mutex is held.
+ */
+ pid_list = rcu_dereference_protected(tr->filtered_pids,
+ mutex_is_locked(&event_mutex));
+ no_pid_list = rcu_dereference_protected(tr->filtered_no_pids,
+ mutex_is_locked(&event_mutex));
+
+ this_cpu_write(tr->array_buffer.data->ignore_pid,
+ trace_ignore_this_task(pid_list, no_pid_list, current));
+}
+
+static void register_pid_events(struct trace_array *tr)
+{
+ /*
+ * Register a probe that is called before all other probes
+ * to set ignore_pid if next or prev do not match.
+ * Register a probe this is called after all other probes
+ * to only keep ignore_pid set if next pid matches.
+ */
+ register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre,
+ tr, INT_MAX);
+ register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post,
+ tr, 0);
+
+ register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre,
+ tr, INT_MAX);
+ register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post,
+ tr, 0);
+
+ register_trace_prio_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_pre,
+ tr, INT_MAX);
+ register_trace_prio_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_post,
+ tr, 0);
+
+ register_trace_prio_sched_waking(event_filter_pid_sched_wakeup_probe_pre,
+ tr, INT_MAX);
+ register_trace_prio_sched_waking(event_filter_pid_sched_wakeup_probe_post,
+ tr, 0);
+}
+
+static ssize_t
+event_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos, int type)
+{
+ struct seq_file *m = filp->private_data;
+ struct trace_array *tr = m->private;
+ struct trace_pid_list *filtered_pids = NULL;
+ struct trace_pid_list *other_pids = NULL;
+ struct trace_pid_list *pid_list;
+ struct trace_event_file *file;
+ ssize_t ret;
+
+ if (!cnt)
+ return 0;
+
+ ret = tracing_update_buffers();
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&event_mutex);
+
+ if (type == TRACE_PIDS) {
+ filtered_pids = rcu_dereference_protected(tr->filtered_pids,
+ lockdep_is_held(&event_mutex));
+ other_pids = rcu_dereference_protected(tr->filtered_no_pids,
+ lockdep_is_held(&event_mutex));
+ } else {
+ filtered_pids = rcu_dereference_protected(tr->filtered_no_pids,
+ lockdep_is_held(&event_mutex));
+ other_pids = rcu_dereference_protected(tr->filtered_pids,
+ lockdep_is_held(&event_mutex));
+ }
+
+ ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt);
+ if (ret < 0)
+ goto out;
+
+ if (type == TRACE_PIDS)
+ rcu_assign_pointer(tr->filtered_pids, pid_list);
+ else
+ rcu_assign_pointer(tr->filtered_no_pids, pid_list);
+
+ list_for_each_entry(file, &tr->events, list) {
+ set_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags);
+ }
+
+ if (filtered_pids) {
+ tracepoint_synchronize_unregister();
+ trace_pid_list_free(filtered_pids);
+ } else if (pid_list && !other_pids) {
+ register_pid_events(tr);
+ }
+
+ /*
+ * Ignoring of pids is done at task switch. But we have to
+ * check for those tasks that are currently running.
+ * Always do this in case a pid was appended or removed.
+ */
+ on_each_cpu(ignore_task_cpu, tr, 1);
+
+ out:
+ mutex_unlock(&event_mutex);
+
+ if (ret > 0)
+ *ppos += ret;
+
+ return ret;
+}
+
+static ssize_t
+ftrace_event_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return event_pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS);
+}
+
+static ssize_t
+ftrace_event_npid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return event_pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS);
+}
+
+static int ftrace_event_avail_open(struct inode *inode, struct file *file);
+static int ftrace_event_set_open(struct inode *inode, struct file *file);
+static int ftrace_event_set_pid_open(struct inode *inode, struct file *file);
+static int ftrace_event_set_npid_open(struct inode *inode, struct file *file);
+static int ftrace_event_release(struct inode *inode, struct file *file);
+
+static const struct seq_operations show_event_seq_ops = {
+ .start = t_start,
+ .next = t_next,
+ .show = t_show,
+ .stop = t_stop,
+};
+
+static const struct seq_operations show_set_event_seq_ops = {
+ .start = s_start,
+ .next = s_next,
+ .show = t_show,
+ .stop = t_stop,
+};
+
+static const struct seq_operations show_set_pid_seq_ops = {
+ .start = p_start,
+ .next = p_next,
+ .show = trace_pid_show,
+ .stop = p_stop,
+};
+
+static const struct seq_operations show_set_no_pid_seq_ops = {
+ .start = np_start,
+ .next = np_next,
+ .show = trace_pid_show,
+ .stop = p_stop,
+};
+
+static const struct file_operations ftrace_avail_fops = {
+ .open = ftrace_event_avail_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static const struct file_operations ftrace_set_event_fops = {
+ .open = ftrace_event_set_open,
+ .read = seq_read,
+ .write = ftrace_event_write,
+ .llseek = seq_lseek,
+ .release = ftrace_event_release,
+};
+
+static const struct file_operations ftrace_set_event_pid_fops = {
+ .open = ftrace_event_set_pid_open,
+ .read = seq_read,
+ .write = ftrace_event_pid_write,
+ .llseek = seq_lseek,
+ .release = ftrace_event_release,
+};
+
+static const struct file_operations ftrace_set_event_notrace_pid_fops = {
+ .open = ftrace_event_set_npid_open,
+ .read = seq_read,
+ .write = ftrace_event_npid_write,
+ .llseek = seq_lseek,
+ .release = ftrace_event_release,
+};
+
+static const struct file_operations ftrace_enable_fops = {
+ .open = tracing_open_file_tr,
+ .read = event_enable_read,
+ .write = event_enable_write,
+ .release = tracing_release_file_tr,
+ .llseek = default_llseek,
+};
+
+static const struct file_operations ftrace_event_format_fops = {
+ .open = trace_format_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static const struct file_operations ftrace_event_id_fops = {
+ .read = event_id_read,
+ .llseek = default_llseek,
+};
+
+static const struct file_operations ftrace_event_filter_fops = {
+ .open = tracing_open_file_tr,
+ .read = event_filter_read,
+ .write = event_filter_write,
+ .release = tracing_release_file_tr,
+ .llseek = default_llseek,
+};
+
+static const struct file_operations ftrace_subsystem_filter_fops = {
+ .open = subsystem_open,
+ .read = subsystem_filter_read,
+ .write = subsystem_filter_write,
+ .llseek = default_llseek,
+ .release = subsystem_release,
+};
+
+static const struct file_operations ftrace_system_enable_fops = {
+ .open = subsystem_open,
+ .read = system_enable_read,
+ .write = system_enable_write,
+ .llseek = default_llseek,
+ .release = subsystem_release,
+};
+
+static const struct file_operations ftrace_tr_enable_fops = {
+ .open = system_tr_open,
+ .read = system_enable_read,
+ .write = system_enable_write,
+ .llseek = default_llseek,
+ .release = subsystem_release,
+};
+
+static const struct file_operations ftrace_show_header_fops = {
+ .open = tracing_open_generic,
+ .read = show_header,
+ .llseek = default_llseek,
+};
+
+static int
+ftrace_event_open(struct inode *inode, struct file *file,
+ const struct seq_operations *seq_ops)
+{
+ struct seq_file *m;
+ int ret;
+
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
+
+ ret = seq_open(file, seq_ops);
+ if (ret < 0)
+ return ret;
+ m = file->private_data;
+ /* copy tr over to seq ops */
+ m->private = inode->i_private;
+
+ return ret;
+}
+
+static int ftrace_event_release(struct inode *inode, struct file *file)
+{
+ struct trace_array *tr = inode->i_private;
+
+ trace_array_put(tr);
+
+ return seq_release(inode, file);
+}
+
+static int
+ftrace_event_avail_open(struct inode *inode, struct file *file)
+{
+ const struct seq_operations *seq_ops = &show_event_seq_ops;
+
+ /* Checks for tracefs lockdown */
+ return ftrace_event_open(inode, file, seq_ops);
+}
+
+static int
+ftrace_event_set_open(struct inode *inode, struct file *file)
+{
+ const struct seq_operations *seq_ops = &show_set_event_seq_ops;
+ struct trace_array *tr = inode->i_private;
+ int ret;
+
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_clear_events(tr);
+
+ ret = ftrace_event_open(inode, file, seq_ops);
+ if (ret < 0)
+ trace_array_put(tr);
+ return ret;
+}
+
+static int
+ftrace_event_set_pid_open(struct inode *inode, struct file *file)
+{
+ const struct seq_operations *seq_ops = &show_set_pid_seq_ops;
+ struct trace_array *tr = inode->i_private;
+ int ret;
+
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_clear_event_pids(tr, TRACE_PIDS);
+
+ ret = ftrace_event_open(inode, file, seq_ops);
+ if (ret < 0)
+ trace_array_put(tr);
+ return ret;
+}
+
+static int
+ftrace_event_set_npid_open(struct inode *inode, struct file *file)
+{
+ const struct seq_operations *seq_ops = &show_set_no_pid_seq_ops;
+ struct trace_array *tr = inode->i_private;
+ int ret;
+
+ ret = tracing_check_open_get_tr(tr);
+ if (ret)
+ return ret;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_clear_event_pids(tr, TRACE_NO_PIDS);
+
+ ret = ftrace_event_open(inode, file, seq_ops);
+ if (ret < 0)
+ trace_array_put(tr);
+ return ret;
+}
+
+static struct event_subsystem *
+create_new_subsystem(const char *name)
+{
+ struct event_subsystem *system;
+
+ /* need to create new entry */
+ system = kmalloc(sizeof(*system), GFP_KERNEL);
+ if (!system)
+ return NULL;
+
+ system->ref_count = 1;
+
+ /* Only allocate if dynamic (kprobes and modules) */
+ system->name = kstrdup_const(name, GFP_KERNEL);
+ if (!system->name)
+ goto out_free;
+
+ system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
+ if (!system->filter)
+ goto out_free;
+
+ list_add(&system->list, &event_subsystems);
+
+ return system;
+
+ out_free:
+ kfree_const(system->name);
+ kfree(system);
+ return NULL;
+}
+
+static struct eventfs_file *
+event_subsystem_dir(struct trace_array *tr, const char *name,
+ struct trace_event_file *file, struct dentry *parent)
+{
+ struct event_subsystem *system, *iter;
+ struct trace_subsystem_dir *dir;
+ struct eventfs_file *ef;
+ int res;
+
+ /* First see if we did not already create this dir */
+ list_for_each_entry(dir, &tr->systems, list) {
+ system = dir->subsystem;
+ if (strcmp(system->name, name) == 0) {
+ dir->nr_events++;
+ file->system = dir;
+ return dir->ef;
+ }
+ }
+
+ /* Now see if the system itself exists. */
+ system = NULL;
+ list_for_each_entry(iter, &event_subsystems, list) {
+ if (strcmp(iter->name, name) == 0) {
+ system = iter;
+ break;
+ }
+ }
+
+ dir = kmalloc(sizeof(*dir), GFP_KERNEL);
+ if (!dir)
+ goto out_fail;
+
+ if (!system) {
+ system = create_new_subsystem(name);
+ if (!system)
+ goto out_free;
+ } else
+ __get_system(system);
+
+ ef = eventfs_add_subsystem_dir(name, parent);
+ if (IS_ERR(ef)) {
+ pr_warn("Failed to create system directory %s\n", name);
+ __put_system(system);
+ goto out_free;
+ }
+
+ dir->ef = ef;
+ dir->tr = tr;
+ dir->ref_count = 1;
+ dir->nr_events = 1;
+ dir->subsystem = system;
+ file->system = dir;
+
+ /* the ftrace system is special, do not create enable or filter files */
+ if (strcmp(name, "ftrace") != 0) {
+
+ res = eventfs_add_file("filter", TRACE_MODE_WRITE,
+ dir->ef, dir,
+ &ftrace_subsystem_filter_fops);
+ if (res) {
+ kfree(system->filter);
+ system->filter = NULL;
+ pr_warn("Could not create tracefs '%s/filter' entry\n", name);
+ }
+
+ eventfs_add_file("enable", TRACE_MODE_WRITE, dir->ef, dir,
+ &ftrace_system_enable_fops);
+ }
+
+ list_add(&dir->list, &tr->systems);
+
+ return dir->ef;
+
+ out_free:
+ kfree(dir);
+ out_fail:
+ /* Only print this message if failed on memory allocation */
+ if (!dir || !system)
+ pr_warn("No memory to create event subsystem %s\n", name);
+ return NULL;
+}
+
+static int
+event_define_fields(struct trace_event_call *call)
+{
+ struct list_head *head;
+ int ret = 0;
+
+ /*
+ * Other events may have the same class. Only update
+ * the fields if they are not already defined.
+ */
+ head = trace_get_fields(call);
+ if (list_empty(head)) {
+ struct trace_event_fields *field = call->class->fields_array;
+ unsigned int offset = sizeof(struct trace_entry);
+
+ for (; field->type; field++) {
+ if (field->type == TRACE_FUNCTION_TYPE) {
+ field->define_fields(call);
+ break;
+ }
+
+ offset = ALIGN(offset, field->align);
+ ret = trace_define_field_ext(call, field->type, field->name,
+ offset, field->size,
+ field->is_signed, field->filter_type,
+ field->len);
+ if (WARN_ON_ONCE(ret)) {
+ pr_err("error code is %d\n", ret);
+ break;
+ }
+
+ offset += field->size;
+ }
+ }
+
+ return ret;
+}
+
+static int
+event_create_dir(struct dentry *parent, struct trace_event_file *file)
+{
+ struct trace_event_call *call = file->event_call;
+ struct eventfs_file *ef_subsystem = NULL;
+ struct trace_array *tr = file->tr;
+ struct eventfs_file *ef;
+ const char *name;
+ int ret;
+
+ /*
+ * If the trace point header did not define TRACE_SYSTEM
+ * then the system would be called "TRACE_SYSTEM". This should
+ * never happen.
+ */
+ if (WARN_ON_ONCE(strcmp(call->class->system, TRACE_SYSTEM) == 0))
+ return -ENODEV;
+
+ ef_subsystem = event_subsystem_dir(tr, call->class->system, file, parent);
+ if (!ef_subsystem)
+ return -ENOMEM;
+
+ name = trace_event_name(call);
+ ef = eventfs_add_dir(name, ef_subsystem);
+ if (IS_ERR(ef)) {
+ pr_warn("Could not create tracefs '%s' directory\n", name);
+ return -1;
+ }
+
+ file->ef = ef;
+
+ if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
+ eventfs_add_file("enable", TRACE_MODE_WRITE, file->ef, file,
+ &ftrace_enable_fops);
+
+#ifdef CONFIG_PERF_EVENTS
+ if (call->event.type && call->class->reg)
+ eventfs_add_file("id", TRACE_MODE_READ, file->ef,
+ (void *)(long)call->event.type,
+ &ftrace_event_id_fops);
+#endif
+
+ ret = event_define_fields(call);
+ if (ret < 0) {
+ pr_warn("Could not initialize trace point events/%s\n", name);
+ return ret;
+ }
+
+ /*
+ * Only event directories that can be enabled should have
+ * triggers or filters.
+ */
+ if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) {
+ eventfs_add_file("filter", TRACE_MODE_WRITE, file->ef,
+ file, &ftrace_event_filter_fops);
+
+ eventfs_add_file("trigger", TRACE_MODE_WRITE, file->ef,
+ file, &event_trigger_fops);
+ }
+
+#ifdef CONFIG_HIST_TRIGGERS
+ eventfs_add_file("hist", TRACE_MODE_READ, file->ef, file,
+ &event_hist_fops);
+#endif
+#ifdef CONFIG_HIST_TRIGGERS_DEBUG
+ eventfs_add_file("hist_debug", TRACE_MODE_READ, file->ef, file,
+ &event_hist_debug_fops);
+#endif
+ eventfs_add_file("format", TRACE_MODE_READ, file->ef, call,
+ &ftrace_event_format_fops);
+
+#ifdef CONFIG_TRACE_EVENT_INJECT
+ if (call->event.type && call->class->reg)
+ eventfs_add_file("inject", 0200, file->ef, file,
+ &event_inject_fops);
+#endif
+
+ return 0;
+}
+
+static void remove_event_from_tracers(struct trace_event_call *call)
+{
+ struct trace_event_file *file;
+ struct trace_array *tr;
+
+ do_for_each_event_file_safe(tr, file) {
+ if (file->event_call != call)
+ continue;
+
+ remove_event_file_dir(file);
+ /*
+ * The do_for_each_event_file_safe() is
+ * a double loop. After finding the call for this
+ * trace_array, we use break to jump to the next
+ * trace_array.
+ */
+ break;
+ } while_for_each_event_file();
+}
+
+static void event_remove(struct trace_event_call *call)
+{
+ struct trace_array *tr;
+ struct trace_event_file *file;
+
+ do_for_each_event_file(tr, file) {
+ if (file->event_call != call)
+ continue;
+
+ if (file->flags & EVENT_FILE_FL_WAS_ENABLED)
+ tr->clear_trace = true;
+
+ ftrace_event_enable_disable(file, 0);
+ /*
+ * The do_for_each_event_file() is
+ * a double loop. After finding the call for this
+ * trace_array, we use break to jump to the next
+ * trace_array.
+ */
+ break;
+ } while_for_each_event_file();
+
+ if (call->event.funcs)
+ __unregister_trace_event(&call->event);
+ remove_event_from_tracers(call);
+ list_del(&call->list);
+}
+
+static int event_init(struct trace_event_call *call)
+{
+ int ret = 0;
+ const char *name;
+
+ name = trace_event_name(call);
+ if (WARN_ON(!name))
+ return -EINVAL;
+
+ if (call->class->raw_init) {
+ ret = call->class->raw_init(call);
+ if (ret < 0 && ret != -ENOSYS)
+ pr_warn("Could not initialize trace events/%s\n", name);
+ }
+
+ return ret;
+}
+
+static int
+__register_event(struct trace_event_call *call, struct module *mod)
+{
+ int ret;
+
+ ret = event_init(call);
+ if (ret < 0)
+ return ret;
+
+ list_add(&call->list, &ftrace_events);
+ if (call->flags & TRACE_EVENT_FL_DYNAMIC)
+ atomic_set(&call->refcnt, 0);
+ else
+ call->module = mod;
+
+ return 0;
+}
+
+static char *eval_replace(char *ptr, struct trace_eval_map *map, int len)
+{
+ int rlen;
+ int elen;
+
+ /* Find the length of the eval value as a string */
+ elen = snprintf(ptr, 0, "%ld", map->eval_value);
+ /* Make sure there's enough room to replace the string with the value */
+ if (len < elen)
+ return NULL;
+
+ snprintf(ptr, elen + 1, "%ld", map->eval_value);
+
+ /* Get the rest of the string of ptr */
+ rlen = strlen(ptr + len);
+ memmove(ptr + elen, ptr + len, rlen);
+ /* Make sure we end the new string */
+ ptr[elen + rlen] = 0;
+
+ return ptr + elen;
+}
+
+static void update_event_printk(struct trace_event_call *call,
+ struct trace_eval_map *map)
+{
+ char *ptr;
+ int quote = 0;
+ int len = strlen(map->eval_string);
+
+ for (ptr = call->print_fmt; *ptr; ptr++) {
+ if (*ptr == '\\') {
+ ptr++;
+ /* paranoid */
+ if (!*ptr)
+ break;
+ continue;
+ }
+ if (*ptr == '"') {
+ quote ^= 1;
+ continue;
+ }
+ if (quote)
+ continue;
+ if (isdigit(*ptr)) {
+ /* skip numbers */
+ do {
+ ptr++;
+ /* Check for alpha chars like ULL */
+ } while (isalnum(*ptr));
+ if (!*ptr)
+ break;
+ /*
+ * A number must have some kind of delimiter after
+ * it, and we can ignore that too.
+ */
+ continue;
+ }
+ if (isalpha(*ptr) || *ptr == '_') {
+ if (strncmp(map->eval_string, ptr, len) == 0 &&
+ !isalnum(ptr[len]) && ptr[len] != '_') {
+ ptr = eval_replace(ptr, map, len);
+ /* enum/sizeof string smaller than value */
+ if (WARN_ON_ONCE(!ptr))
+ return;
+ /*
+ * No need to decrement here, as eval_replace()
+ * returns the pointer to the character passed
+ * the eval, and two evals can not be placed
+ * back to back without something in between.
+ * We can skip that something in between.
+ */
+ continue;
+ }
+ skip_more:
+ do {
+ ptr++;
+ } while (isalnum(*ptr) || *ptr == '_');
+ if (!*ptr)
+ break;
+ /*
+ * If what comes after this variable is a '.' or
+ * '->' then we can continue to ignore that string.
+ */
+ if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) {
+ ptr += *ptr == '.' ? 1 : 2;
+ if (!*ptr)
+ break;
+ goto skip_more;
+ }
+ /*
+ * Once again, we can skip the delimiter that came
+ * after the string.
+ */
+ continue;
+ }
+ }
+}
+
+static void add_str_to_module(struct module *module, char *str)
+{
+ struct module_string *modstr;
+
+ modstr = kmalloc(sizeof(*modstr), GFP_KERNEL);
+
+ /*
+ * If we failed to allocate memory here, then we'll just
+ * let the str memory leak when the module is removed.
+ * If this fails to allocate, there's worse problems than
+ * a leaked string on module removal.
+ */
+ if (WARN_ON_ONCE(!modstr))
+ return;
+
+ modstr->module = module;
+ modstr->str = str;
+
+ list_add(&modstr->next, &module_strings);
+}
+
+static void update_event_fields(struct trace_event_call *call,
+ struct trace_eval_map *map)
+{
+ struct ftrace_event_field *field;
+ struct list_head *head;
+ char *ptr;
+ char *str;
+ int len = strlen(map->eval_string);
+
+ /* Dynamic events should never have field maps */
+ if (WARN_ON_ONCE(call->flags & TRACE_EVENT_FL_DYNAMIC))
+ return;
+
+ head = trace_get_fields(call);
+ list_for_each_entry(field, head, link) {
+ ptr = strchr(field->type, '[');
+ if (!ptr)
+ continue;
+ ptr++;
+
+ if (!isalpha(*ptr) && *ptr != '_')
+ continue;
+
+ if (strncmp(map->eval_string, ptr, len) != 0)
+ continue;
+
+ str = kstrdup(field->type, GFP_KERNEL);
+ if (WARN_ON_ONCE(!str))
+ return;
+ ptr = str + (ptr - field->type);
+ ptr = eval_replace(ptr, map, len);
+ /* enum/sizeof string smaller than value */
+ if (WARN_ON_ONCE(!ptr)) {
+ kfree(str);
+ continue;
+ }
+
+ /*
+ * If the event is part of a module, then we need to free the string
+ * when the module is removed. Otherwise, it will stay allocated
+ * until a reboot.
+ */
+ if (call->module)
+ add_str_to_module(call->module, str);
+
+ field->type = str;
+ }
+}
+
+void trace_event_eval_update(struct trace_eval_map **map, int len)
+{
+ struct trace_event_call *call, *p;
+ const char *last_system = NULL;
+ bool first = false;
+ int last_i;
+ int i;
+
+ down_write(&trace_event_sem);
+ list_for_each_entry_safe(call, p, &ftrace_events, list) {
+ /* events are usually grouped together with systems */
+ if (!last_system || call->class->system != last_system) {
+ first = true;
+ last_i = 0;
+ last_system = call->class->system;
+ }
+
+ /*
+ * Since calls are grouped by systems, the likelihood that the
+ * next call in the iteration belongs to the same system as the
+ * previous call is high. As an optimization, we skip searching
+ * for a map[] that matches the call's system if the last call
+ * was from the same system. That's what last_i is for. If the
+ * call has the same system as the previous call, then last_i
+ * will be the index of the first map[] that has a matching
+ * system.
+ */
+ for (i = last_i; i < len; i++) {
+ if (call->class->system == map[i]->system) {
+ /* Save the first system if need be */
+ if (first) {
+ last_i = i;
+ first = false;
+ }
+ update_event_printk(call, map[i]);
+ update_event_fields(call, map[i]);
+ }
+ }
+ cond_resched();
+ }
+ up_write(&trace_event_sem);
+}
+
+static struct trace_event_file *
+trace_create_new_event(struct trace_event_call *call,
+ struct trace_array *tr)
+{
+ struct trace_pid_list *no_pid_list;
+ struct trace_pid_list *pid_list;
+ struct trace_event_file *file;
+ unsigned int first;
+
+ file = kmem_cache_alloc(file_cachep, GFP_TRACE);
+ if (!file)
+ return NULL;
+
+ pid_list = rcu_dereference_protected(tr->filtered_pids,
+ lockdep_is_held(&event_mutex));
+ no_pid_list = rcu_dereference_protected(tr->filtered_no_pids,
+ lockdep_is_held(&event_mutex));
+
+ if (!trace_pid_list_first(pid_list, &first) ||
+ !trace_pid_list_first(no_pid_list, &first))
+ file->flags |= EVENT_FILE_FL_PID_FILTER;
+
+ file->event_call = call;
+ file->tr = tr;
+ atomic_set(&file->sm_ref, 0);
+ atomic_set(&file->tm_ref, 0);
+ INIT_LIST_HEAD(&file->triggers);
+ list_add(&file->list, &tr->events);
+ event_file_get(file);
+
+ return file;
+}
+
+#define MAX_BOOT_TRIGGERS 32
+
+static struct boot_triggers {
+ const char *event;
+ char *trigger;
+} bootup_triggers[MAX_BOOT_TRIGGERS];
+
+static char bootup_trigger_buf[COMMAND_LINE_SIZE];
+static int nr_boot_triggers;
+
+static __init int setup_trace_triggers(char *str)
+{
+ char *trigger;
+ char *buf;
+ int i;
+
+ strscpy(bootup_trigger_buf, str, COMMAND_LINE_SIZE);
+ ring_buffer_expanded = true;
+ disable_tracing_selftest("running event triggers");
+
+ buf = bootup_trigger_buf;
+ for (i = 0; i < MAX_BOOT_TRIGGERS; i++) {
+ trigger = strsep(&buf, ",");
+ if (!trigger)
+ break;
+ bootup_triggers[i].event = strsep(&trigger, ".");
+ bootup_triggers[i].trigger = trigger;
+ if (!bootup_triggers[i].trigger)
+ break;
+ }
+
+ nr_boot_triggers = i;
+ return 1;
+}
+__setup("trace_trigger=", setup_trace_triggers);
+
+/* Add an event to a trace directory */
+static int
+__trace_add_new_event(struct trace_event_call *call, struct trace_array *tr)
+{
+ struct trace_event_file *file;
+
+ file = trace_create_new_event(call, tr);
+ if (!file)
+ return -ENOMEM;
+
+ if (eventdir_initialized)
+ return event_create_dir(tr->event_dir, file);
+ else
+ return event_define_fields(call);
+}
+
+static void trace_early_triggers(struct trace_event_file *file, const char *name)
+{
+ int ret;
+ int i;
+
+ for (i = 0; i < nr_boot_triggers; i++) {
+ if (strcmp(name, bootup_triggers[i].event))
+ continue;
+ mutex_lock(&event_mutex);
+ ret = trigger_process_regex(file, bootup_triggers[i].trigger);
+ mutex_unlock(&event_mutex);
+ if (ret)
+ pr_err("Failed to register trigger '%s' on event %s\n",
+ bootup_triggers[i].trigger,
+ bootup_triggers[i].event);
+ }
+}
+
+/*
+ * Just create a descriptor for early init. A descriptor is required
+ * for enabling events at boot. We want to enable events before
+ * the filesystem is initialized.
+ */
+static int
+__trace_early_add_new_event(struct trace_event_call *call,
+ struct trace_array *tr)
+{
+ struct trace_event_file *file;
+ int ret;
+
+ file = trace_create_new_event(call, tr);
+ if (!file)
+ return -ENOMEM;
+
+ ret = event_define_fields(call);
+ if (ret)
+ return ret;
+
+ trace_early_triggers(file, trace_event_name(call));
+
+ return 0;
+}
+
+struct ftrace_module_file_ops;
+static void __add_event_to_tracers(struct trace_event_call *call);
+
+/* Add an additional event_call dynamically */
+int trace_add_event_call(struct trace_event_call *call)
+{
+ int ret;
+ lockdep_assert_held(&event_mutex);
+
+ mutex_lock(&trace_types_lock);
+
+ ret = __register_event(call, NULL);
+ if (ret >= 0)
+ __add_event_to_tracers(call);
+
+ mutex_unlock(&trace_types_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(trace_add_event_call);
+
+/*
+ * Must be called under locking of trace_types_lock, event_mutex and
+ * trace_event_sem.
+ */
+static void __trace_remove_event_call(struct trace_event_call *call)
+{
+ event_remove(call);
+ trace_destroy_fields(call);
+ free_event_filter(call->filter);
+ call->filter = NULL;
+}
+
+static int probe_remove_event_call(struct trace_event_call *call)
+{
+ struct trace_array *tr;
+ struct trace_event_file *file;
+
+#ifdef CONFIG_PERF_EVENTS
+ if (call->perf_refcount)
+ return -EBUSY;
+#endif
+ do_for_each_event_file(tr, file) {
+ if (file->event_call != call)
+ continue;
+ /*
+ * We can't rely on ftrace_event_enable_disable(enable => 0)
+ * we are going to do, EVENT_FILE_FL_SOFT_MODE can suppress
+ * TRACE_REG_UNREGISTER.
+ */
+ if (file->flags & EVENT_FILE_FL_ENABLED)
+ goto busy;
+
+ if (file->flags & EVENT_FILE_FL_WAS_ENABLED)
+ tr->clear_trace = true;
+ /*
+ * The do_for_each_event_file_safe() is
+ * a double loop. After finding the call for this
+ * trace_array, we use break to jump to the next
+ * trace_array.
+ */
+ break;
+ } while_for_each_event_file();
+
+ __trace_remove_event_call(call);
+
+ return 0;
+ busy:
+ /* No need to clear the trace now */
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ tr->clear_trace = false;
+ }
+ return -EBUSY;
+}
+
+/* Remove an event_call */
+int trace_remove_event_call(struct trace_event_call *call)
+{
+ int ret;
+
+ lockdep_assert_held(&event_mutex);
+
+ mutex_lock(&trace_types_lock);
+ down_write(&trace_event_sem);
+ ret = probe_remove_event_call(call);
+ up_write(&trace_event_sem);
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(trace_remove_event_call);
+
+#define for_each_event(event, start, end) \
+ for (event = start; \
+ (unsigned long)event < (unsigned long)end; \
+ event++)
+
+#ifdef CONFIG_MODULES
+
+static void trace_module_add_events(struct module *mod)
+{
+ struct trace_event_call **call, **start, **end;
+
+ if (!mod->num_trace_events)
+ return;
+
+ /* Don't add infrastructure for mods without tracepoints */
+ if (trace_module_has_bad_taint(mod)) {
+ pr_err("%s: module has bad taint, not creating trace events\n",
+ mod->name);
+ return;
+ }
+
+ start = mod->trace_events;
+ end = mod->trace_events + mod->num_trace_events;
+
+ for_each_event(call, start, end) {
+ __register_event(*call, mod);
+ __add_event_to_tracers(*call);
+ }
+}
+
+static void trace_module_remove_events(struct module *mod)
+{
+ struct trace_event_call *call, *p;
+ struct module_string *modstr, *m;
+
+ down_write(&trace_event_sem);
+ list_for_each_entry_safe(call, p, &ftrace_events, list) {
+ if ((call->flags & TRACE_EVENT_FL_DYNAMIC) || !call->module)
+ continue;
+ if (call->module == mod)
+ __trace_remove_event_call(call);
+ }
+ /* Check for any strings allocade for this module */
+ list_for_each_entry_safe(modstr, m, &module_strings, next) {
+ if (modstr->module != mod)
+ continue;
+ list_del(&modstr->next);
+ kfree(modstr->str);
+ kfree(modstr);
+ }
+ up_write(&trace_event_sem);
+
+ /*
+ * It is safest to reset the ring buffer if the module being unloaded
+ * registered any events that were used. The only worry is if
+ * a new module gets loaded, and takes on the same id as the events
+ * of this module. When printing out the buffer, traced events left
+ * over from this module may be passed to the new module events and
+ * unexpected results may occur.
+ */
+ tracing_reset_all_online_cpus_unlocked();
+}
+
+static int trace_module_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+
+ mutex_lock(&event_mutex);
+ mutex_lock(&trace_types_lock);
+ switch (val) {
+ case MODULE_STATE_COMING:
+ trace_module_add_events(mod);
+ break;
+ case MODULE_STATE_GOING:
+ trace_module_remove_events(mod);
+ break;
+ }
+ mutex_unlock(&trace_types_lock);
+ mutex_unlock(&event_mutex);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block trace_module_nb = {
+ .notifier_call = trace_module_notify,
+ .priority = 1, /* higher than trace.c module notify */
+};
+#endif /* CONFIG_MODULES */
+
+/* Create a new event directory structure for a trace directory. */
+static void
+__trace_add_event_dirs(struct trace_array *tr)
+{
+ struct trace_event_call *call;
+ int ret;
+
+ list_for_each_entry(call, &ftrace_events, list) {
+ ret = __trace_add_new_event(call, tr);
+ if (ret < 0)
+ pr_warn("Could not create directory for event %s\n",
+ trace_event_name(call));
+ }
+}
+
+/* Returns any file that matches the system and event */
+struct trace_event_file *
+__find_event_file(struct trace_array *tr, const char *system, const char *event)
+{
+ struct trace_event_file *file;
+ struct trace_event_call *call;
+ const char *name;
+
+ list_for_each_entry(file, &tr->events, list) {
+
+ call = file->event_call;
+ name = trace_event_name(call);
+
+ if (!name || !call->class)
+ continue;
+
+ if (strcmp(event, name) == 0 &&
+ strcmp(system, call->class->system) == 0)
+ return file;
+ }
+ return NULL;
+}
+
+/* Returns valid trace event files that match system and event */
+struct trace_event_file *
+find_event_file(struct trace_array *tr, const char *system, const char *event)
+{
+ struct trace_event_file *file;
+
+ file = __find_event_file(tr, system, event);
+ if (!file || !file->event_call->class->reg ||
+ file->event_call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
+ return NULL;
+
+ return file;
+}
+
+/**
+ * trace_get_event_file - Find and return a trace event file
+ * @instance: The name of the trace instance containing the event
+ * @system: The name of the system containing the event
+ * @event: The name of the event
+ *
+ * Return a trace event file given the trace instance name, trace
+ * system, and trace event name. If the instance name is NULL, it
+ * refers to the top-level trace array.
+ *
+ * This function will look it up and return it if found, after calling
+ * trace_array_get() to prevent the instance from going away, and
+ * increment the event's module refcount to prevent it from being
+ * removed.
+ *
+ * To release the file, call trace_put_event_file(), which will call
+ * trace_array_put() and decrement the event's module refcount.
+ *
+ * Return: The trace event on success, ERR_PTR otherwise.
+ */
+struct trace_event_file *trace_get_event_file(const char *instance,
+ const char *system,
+ const char *event)
+{
+ struct trace_array *tr = top_trace_array();
+ struct trace_event_file *file = NULL;
+ int ret = -EINVAL;
+
+ if (instance) {
+ tr = trace_array_find_get(instance);
+ if (!tr)
+ return ERR_PTR(-ENOENT);
+ } else {
+ ret = trace_array_get(tr);
+ if (ret)
+ return ERR_PTR(ret);
+ }
+
+ mutex_lock(&event_mutex);
+
+ file = find_event_file(tr, system, event);
+ if (!file) {
+ trace_array_put(tr);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ /* Don't let event modules unload while in use */
+ ret = trace_event_try_get_ref(file->event_call);
+ if (!ret) {
+ trace_array_put(tr);
+ ret = -EBUSY;
+ goto out;
+ }
+
+ ret = 0;
+ out:
+ mutex_unlock(&event_mutex);
+
+ if (ret)
+ file = ERR_PTR(ret);
+
+ return file;
+}
+EXPORT_SYMBOL_GPL(trace_get_event_file);
+
+/**
+ * trace_put_event_file - Release a file from trace_get_event_file()
+ * @file: The trace event file
+ *
+ * If a file was retrieved using trace_get_event_file(), this should
+ * be called when it's no longer needed. It will cancel the previous
+ * trace_array_get() called by that function, and decrement the
+ * event's module refcount.
+ */
+void trace_put_event_file(struct trace_event_file *file)
+{
+ mutex_lock(&event_mutex);
+ trace_event_put_ref(file->event_call);
+ mutex_unlock(&event_mutex);
+
+ trace_array_put(file->tr);
+}
+EXPORT_SYMBOL_GPL(trace_put_event_file);
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+/* Avoid typos */
+#define ENABLE_EVENT_STR "enable_event"
+#define DISABLE_EVENT_STR "disable_event"
+
+struct event_probe_data {
+ struct trace_event_file *file;
+ unsigned long count;
+ int ref;
+ bool enable;
+};
+
+static void update_event_probe(struct event_probe_data *data)
+{
+ if (data->enable)
+ clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags);
+ else
+ set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags);
+}
+
+static void
+event_enable_probe(unsigned long ip, unsigned long parent_ip,
+ struct trace_array *tr, struct ftrace_probe_ops *ops,
+ void *data)
+{
+ struct ftrace_func_mapper *mapper = data;
+ struct event_probe_data *edata;
+ void **pdata;
+
+ pdata = ftrace_func_mapper_find_ip(mapper, ip);
+ if (!pdata || !*pdata)
+ return;
+
+ edata = *pdata;
+ update_event_probe(edata);
+}
+
+static void
+event_enable_count_probe(unsigned long ip, unsigned long parent_ip,
+ struct trace_array *tr, struct ftrace_probe_ops *ops,
+ void *data)
+{
+ struct ftrace_func_mapper *mapper = data;
+ struct event_probe_data *edata;
+ void **pdata;
+
+ pdata = ftrace_func_mapper_find_ip(mapper, ip);
+ if (!pdata || !*pdata)
+ return;
+
+ edata = *pdata;
+
+ if (!edata->count)
+ return;
+
+ /* Skip if the event is in a state we want to switch to */
+ if (edata->enable == !(edata->file->flags & EVENT_FILE_FL_SOFT_DISABLED))
+ return;
+
+ if (edata->count != -1)
+ (edata->count)--;
+
+ update_event_probe(edata);
+}
+
+static int
+event_enable_print(struct seq_file *m, unsigned long ip,
+ struct ftrace_probe_ops *ops, void *data)
+{
+ struct ftrace_func_mapper *mapper = data;
+ struct event_probe_data *edata;
+ void **pdata;
+
+ pdata = ftrace_func_mapper_find_ip(mapper, ip);
+
+ if (WARN_ON_ONCE(!pdata || !*pdata))
+ return 0;
+
+ edata = *pdata;
+
+ seq_printf(m, "%ps:", (void *)ip);
+
+ seq_printf(m, "%s:%s:%s",
+ edata->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR,
+ edata->file->event_call->class->system,
+ trace_event_name(edata->file->event_call));
+
+ if (edata->count == -1)
+ seq_puts(m, ":unlimited\n");
+ else
+ seq_printf(m, ":count=%ld\n", edata->count);
+
+ return 0;
+}
+
+static int
+event_enable_init(struct ftrace_probe_ops *ops, struct trace_array *tr,
+ unsigned long ip, void *init_data, void **data)
+{
+ struct ftrace_func_mapper *mapper = *data;
+ struct event_probe_data *edata = init_data;
+ int ret;
+
+ if (!mapper) {
+ mapper = allocate_ftrace_func_mapper();
+ if (!mapper)
+ return -ENODEV;
+ *data = mapper;
+ }
+
+ ret = ftrace_func_mapper_add_ip(mapper, ip, edata);
+ if (ret < 0)
+ return ret;
+
+ edata->ref++;
+
+ return 0;
+}
+
+static int free_probe_data(void *data)
+{
+ struct event_probe_data *edata = data;
+
+ edata->ref--;
+ if (!edata->ref) {
+ /* Remove the SOFT_MODE flag */
+ __ftrace_event_enable_disable(edata->file, 0, 1);
+ trace_event_put_ref(edata->file->event_call);
+ kfree(edata);
+ }
+ return 0;
+}
+
+static void
+event_enable_free(struct ftrace_probe_ops *ops, struct trace_array *tr,
+ unsigned long ip, void *data)
+{
+ struct ftrace_func_mapper *mapper = data;
+ struct event_probe_data *edata;
+
+ if (!ip) {
+ if (!mapper)
+ return;
+ free_ftrace_func_mapper(mapper, free_probe_data);
+ return;
+ }
+
+ edata = ftrace_func_mapper_remove_ip(mapper, ip);
+
+ if (WARN_ON_ONCE(!edata))
+ return;
+
+ if (WARN_ON_ONCE(edata->ref <= 0))
+ return;
+
+ free_probe_data(edata);
+}
+
+static struct ftrace_probe_ops event_enable_probe_ops = {
+ .func = event_enable_probe,
+ .print = event_enable_print,
+ .init = event_enable_init,
+ .free = event_enable_free,
+};
+
+static struct ftrace_probe_ops event_enable_count_probe_ops = {
+ .func = event_enable_count_probe,
+ .print = event_enable_print,
+ .init = event_enable_init,
+ .free = event_enable_free,
+};
+
+static struct ftrace_probe_ops event_disable_probe_ops = {
+ .func = event_enable_probe,
+ .print = event_enable_print,
+ .init = event_enable_init,
+ .free = event_enable_free,
+};
+
+static struct ftrace_probe_ops event_disable_count_probe_ops = {
+ .func = event_enable_count_probe,
+ .print = event_enable_print,
+ .init = event_enable_init,
+ .free = event_enable_free,
+};
+
+static int
+event_enable_func(struct trace_array *tr, struct ftrace_hash *hash,
+ char *glob, char *cmd, char *param, int enabled)
+{
+ struct trace_event_file *file;
+ struct ftrace_probe_ops *ops;
+ struct event_probe_data *data;
+ const char *system;
+ const char *event;
+ char *number;
+ bool enable;
+ int ret;
+
+ if (!tr)
+ return -ENODEV;
+
+ /* hash funcs only work with set_ftrace_filter */
+ if (!enabled || !param)
+ return -EINVAL;
+
+ system = strsep(&param, ":");
+ if (!param)
+ return -EINVAL;
+
+ event = strsep(&param, ":");
+
+ mutex_lock(&event_mutex);
+
+ ret = -EINVAL;
+ file = find_event_file(tr, system, event);
+ if (!file)
+ goto out;
+
+ enable = strcmp(cmd, ENABLE_EVENT_STR) == 0;
+
+ if (enable)
+ ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops;
+ else
+ ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops;
+
+ if (glob[0] == '!') {
+ ret = unregister_ftrace_function_probe_func(glob+1, tr, ops);
+ goto out;
+ }
+
+ ret = -ENOMEM;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ goto out;
+
+ data->enable = enable;
+ data->count = -1;
+ data->file = file;
+
+ if (!param)
+ goto out_reg;
+
+ number = strsep(&param, ":");
+
+ 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, &data->count);
+ if (ret)
+ goto out_free;
+
+ out_reg:
+ /* Don't let event modules unload while probe registered */
+ ret = trace_event_try_get_ref(file->event_call);
+ if (!ret) {
+ ret = -EBUSY;
+ goto out_free;
+ }
+
+ ret = __ftrace_event_enable_disable(file, 1, 1);
+ if (ret < 0)
+ goto out_put;
+
+ ret = register_ftrace_function_probe(glob, tr, ops, data);
+ /*
+ * 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;
+ out:
+ mutex_unlock(&event_mutex);
+ return ret;
+
+ out_disable:
+ __ftrace_event_enable_disable(file, 0, 1);
+ out_put:
+ trace_event_put_ref(file->event_call);
+ out_free:
+ kfree(data);
+ goto out;
+}
+
+static struct ftrace_func_command event_enable_cmd = {
+ .name = ENABLE_EVENT_STR,
+ .func = event_enable_func,
+};
+
+static struct ftrace_func_command event_disable_cmd = {
+ .name = DISABLE_EVENT_STR,
+ .func = event_enable_func,
+};
+
+static __init int register_event_cmds(void)
+{
+ int ret;
+
+ ret = register_ftrace_command(&event_enable_cmd);
+ if (WARN_ON(ret < 0))
+ return ret;
+ ret = register_ftrace_command(&event_disable_cmd);
+ if (WARN_ON(ret < 0))
+ unregister_ftrace_command(&event_enable_cmd);
+ return ret;
+}
+#else
+static inline int register_event_cmds(void) { return 0; }
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+/*
+ * The top level array and trace arrays created by boot-time tracing
+ * have already had its trace_event_file descriptors created in order
+ * to allow for early events to be recorded.
+ * This function is called after the tracefs has been initialized,
+ * and we now have to create the files associated to the events.
+ */
+static void __trace_early_add_event_dirs(struct trace_array *tr)
+{
+ struct trace_event_file *file;
+ int ret;
+
+
+ list_for_each_entry(file, &tr->events, list) {
+ ret = event_create_dir(tr->event_dir, file);
+ if (ret < 0)
+ pr_warn("Could not create directory for event %s\n",
+ trace_event_name(file->event_call));
+ }
+}
+
+/*
+ * For early boot up, the top trace array and the trace arrays created
+ * by boot-time tracing require to have a list of events that can be
+ * enabled. This must be done before the filesystem is set up in order
+ * to allow events to be traced early.
+ */
+void __trace_early_add_events(struct trace_array *tr)
+{
+ struct trace_event_call *call;
+ int ret;
+
+ list_for_each_entry(call, &ftrace_events, list) {
+ /* Early boot up should not have any modules loaded */
+ if (!(call->flags & TRACE_EVENT_FL_DYNAMIC) &&
+ WARN_ON_ONCE(call->module))
+ continue;
+
+ ret = __trace_early_add_new_event(call, tr);
+ if (ret < 0)
+ pr_warn("Could not create early event %s\n",
+ trace_event_name(call));
+ }
+}
+
+/* Remove the event directory structure for a trace directory. */
+static void
+__trace_remove_event_dirs(struct trace_array *tr)
+{
+ struct trace_event_file *file, *next;
+
+ list_for_each_entry_safe(file, next, &tr->events, list)
+ remove_event_file_dir(file);
+}
+
+static void __add_event_to_tracers(struct trace_event_call *call)
+{
+ struct trace_array *tr;
+
+ list_for_each_entry(tr, &ftrace_trace_arrays, list)
+ __trace_add_new_event(call, tr);
+}
+
+extern struct trace_event_call *__start_ftrace_events[];
+extern struct trace_event_call *__stop_ftrace_events[];
+
+static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
+
+static __init int setup_trace_event(char *str)
+{
+ strscpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
+ ring_buffer_expanded = true;
+ disable_tracing_selftest("running event tracing");
+
+ return 1;
+}
+__setup("trace_event=", setup_trace_event);
+
+/* Expects to have event_mutex held when called */
+static int
+create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
+{
+ struct dentry *d_events;
+ struct dentry *entry;
+ int error = 0;
+
+ entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent,
+ tr, &ftrace_set_event_fops);
+ if (!entry)
+ return -ENOMEM;
+
+ d_events = eventfs_create_events_dir("events", parent);
+ if (IS_ERR(d_events)) {
+ pr_warn("Could not create tracefs 'events' directory\n");
+ return -ENOMEM;
+ }
+
+ error = eventfs_add_events_file("enable", TRACE_MODE_WRITE, d_events,
+ tr, &ftrace_tr_enable_fops);
+ if (error)
+ return -ENOMEM;
+
+ /* There are not as crucial, just warn if they are not created */
+
+ trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
+ tr, &ftrace_set_event_pid_fops);
+
+ trace_create_file("set_event_notrace_pid",
+ TRACE_MODE_WRITE, parent, tr,
+ &ftrace_set_event_notrace_pid_fops);
+
+ /* ring buffer internal formats */
+ eventfs_add_events_file("header_page", TRACE_MODE_READ, d_events,
+ ring_buffer_print_page_header,
+ &ftrace_show_header_fops);
+
+ eventfs_add_events_file("header_event", TRACE_MODE_READ, d_events,
+ ring_buffer_print_entry_header,
+ &ftrace_show_header_fops);
+
+ tr->event_dir = d_events;
+
+ return 0;
+}
+
+/**
+ * event_trace_add_tracer - add a instance of a trace_array to events
+ * @parent: The parent dentry to place the files/directories for events in
+ * @tr: The trace array associated with these events
+ *
+ * When a new instance is created, it needs to set up its events
+ * directory, as well as other files associated with events. It also
+ * creates the event hierarchy in the @parent/events directory.
+ *
+ * Returns 0 on success.
+ *
+ * Must be called with event_mutex held.
+ */
+int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr)
+{
+ int ret;
+
+ lockdep_assert_held(&event_mutex);
+
+ ret = create_event_toplevel_files(parent, tr);
+ if (ret)
+ goto out;
+
+ down_write(&trace_event_sem);
+ /* If tr already has the event list, it is initialized in early boot. */
+ if (unlikely(!list_empty(&tr->events)))
+ __trace_early_add_event_dirs(tr);
+ else
+ __trace_add_event_dirs(tr);
+ up_write(&trace_event_sem);
+
+ out:
+ return ret;
+}
+
+/*
+ * The top trace array already had its file descriptors created.
+ * Now the files themselves need to be created.
+ */
+static __init int
+early_event_add_tracer(struct dentry *parent, struct trace_array *tr)
+{
+ int ret;
+
+ mutex_lock(&event_mutex);
+
+ ret = create_event_toplevel_files(parent, tr);
+ if (ret)
+ goto out_unlock;
+
+ down_write(&trace_event_sem);
+ __trace_early_add_event_dirs(tr);
+ up_write(&trace_event_sem);
+
+ out_unlock:
+ mutex_unlock(&event_mutex);
+
+ return ret;
+}
+
+/* Must be called with event_mutex held */
+int event_trace_del_tracer(struct trace_array *tr)
+{
+ lockdep_assert_held(&event_mutex);
+
+ /* Disable any event triggers and associated soft-disabled events */
+ clear_event_triggers(tr);
+
+ /* Clear the pid list */
+ __ftrace_clear_event_pids(tr, TRACE_PIDS | TRACE_NO_PIDS);
+
+ /* Disable any running events */
+ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
+
+ /* Make sure no more events are being executed */
+ tracepoint_synchronize_unregister();
+
+ down_write(&trace_event_sem);
+ __trace_remove_event_dirs(tr);
+ eventfs_remove_events_dir(tr->event_dir);
+ up_write(&trace_event_sem);
+
+ tr->event_dir = NULL;
+
+ return 0;
+}
+
+static __init int event_trace_memsetup(void)
+{
+ field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC);
+ file_cachep = KMEM_CACHE(trace_event_file, SLAB_PANIC);
+ return 0;
+}
+
+__init void
+early_enable_events(struct trace_array *tr, char *buf, bool disable_first)
+{
+ char *token;
+ int ret;
+
+ while (true) {
+ token = strsep(&buf, ",");
+
+ if (!token)
+ break;
+
+ if (*token) {
+ /* Restarting syscalls requires that we stop them first */
+ if (disable_first)
+ ftrace_set_clr_event(tr, token, 0);
+
+ ret = ftrace_set_clr_event(tr, token, 1);
+ if (ret)
+ pr_warn("Failed to enable trace event: %s\n", token);
+ }
+
+ /* Put back the comma to allow this to be called again */
+ if (buf)
+ *(buf - 1) = ',';
+ }
+}
+
+static __init int event_trace_enable(void)
+{
+ struct trace_array *tr = top_trace_array();
+ struct trace_event_call **iter, *call;
+ int ret;
+
+ if (!tr)
+ return -ENODEV;
+
+ for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
+
+ call = *iter;
+ ret = event_init(call);
+ if (!ret)
+ list_add(&call->list, &ftrace_events);
+ }
+
+ register_trigger_cmds();
+
+ /*
+ * We need the top trace array to have a working set of trace
+ * points at early init, before the debug files and directories
+ * are created. Create the file entries now, and attach them
+ * to the actual file dentries later.
+ */
+ __trace_early_add_events(tr);
+
+ early_enable_events(tr, bootup_event_buf, false);
+
+ trace_printk_start_comm();
+
+ register_event_cmds();
+
+
+ return 0;
+}
+
+/*
+ * event_trace_enable() is called from trace_event_init() first to
+ * initialize events and perhaps start any events that are on the
+ * command line. Unfortunately, there are some events that will not
+ * start this early, like the system call tracepoints that need
+ * to set the %SYSCALL_WORK_SYSCALL_TRACEPOINT flag of pid 1. But
+ * event_trace_enable() is called before pid 1 starts, and this flag
+ * is never set, making the syscall tracepoint never get reached, but
+ * the event is enabled regardless (and not doing anything).
+ */
+static __init int event_trace_enable_again(void)
+{
+ struct trace_array *tr;
+
+ tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
+
+ early_enable_events(tr, bootup_event_buf, true);
+
+ return 0;
+}
+
+early_initcall(event_trace_enable_again);
+
+/* Init fields which doesn't related to the tracefs */
+static __init int event_trace_init_fields(void)
+{
+ if (trace_define_generic_fields())
+ pr_warn("tracing: Failed to allocated generic fields");
+
+ if (trace_define_common_fields())
+ pr_warn("tracing: Failed to allocate common fields");
+
+ return 0;
+}
+
+__init int event_trace_init(void)
+{
+ struct trace_array *tr;
+ int ret;
+
+ tr = top_trace_array();
+ if (!tr)
+ return -ENODEV;
+
+ trace_create_file("available_events", TRACE_MODE_READ,
+ NULL, tr, &ftrace_avail_fops);
+
+ ret = early_event_add_tracer(NULL, tr);
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_MODULES
+ ret = register_module_notifier(&trace_module_nb);
+ if (ret)
+ pr_warn("Failed to register trace events module notifier\n");
+#endif
+
+ eventdir_initialized = true;
+
+ return 0;
+}
+
+void __init trace_event_init(void)
+{
+ event_trace_memsetup();
+ init_ftrace_syscalls();
+ event_trace_enable();
+ event_trace_init_fields();
+}
+
+#ifdef CONFIG_EVENT_TRACE_STARTUP_TEST
+
+static DEFINE_SPINLOCK(test_spinlock);
+static DEFINE_SPINLOCK(test_spinlock_irq);
+static DEFINE_MUTEX(test_mutex);
+
+static __init void test_work(struct work_struct *dummy)
+{
+ spin_lock(&test_spinlock);
+ spin_lock_irq(&test_spinlock_irq);
+ udelay(1);
+ spin_unlock_irq(&test_spinlock_irq);
+ spin_unlock(&test_spinlock);
+
+ mutex_lock(&test_mutex);
+ msleep(1);
+ mutex_unlock(&test_mutex);
+}
+
+static __init int event_test_thread(void *unused)
+{
+ void *test_malloc;
+
+ test_malloc = kmalloc(1234, GFP_KERNEL);
+ if (!test_malloc)
+ pr_info("failed to kmalloc\n");
+
+ schedule_on_each_cpu(test_work);
+
+ kfree(test_malloc);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ while (!kthread_should_stop()) {
+ schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+ __set_current_state(TASK_RUNNING);
+
+ return 0;
+}
+
+/*
+ * Do various things that may trigger events.
+ */
+static __init void event_test_stuff(void)
+{
+ struct task_struct *test_thread;
+
+ test_thread = kthread_run(event_test_thread, NULL, "test-events");
+ msleep(1);
+ kthread_stop(test_thread);
+}
+
+/*
+ * For every trace event defined, we will test each trace point separately,
+ * and then by groups, and finally all trace points.
+ */
+static __init void event_trace_self_tests(void)
+{
+ struct trace_subsystem_dir *dir;
+ struct trace_event_file *file;
+ struct trace_event_call *call;
+ struct event_subsystem *system;
+ struct trace_array *tr;
+ int ret;
+
+ tr = top_trace_array();
+ if (!tr)
+ return;
+
+ pr_info("Running tests on trace events:\n");
+
+ list_for_each_entry(file, &tr->events, list) {
+
+ call = file->event_call;
+
+ /* Only test those that have a probe */
+ if (!call->class || !call->class->probe)
+ continue;
+
+/*
+ * Testing syscall events here is pretty useless, but
+ * we still do it if configured. But this is time consuming.
+ * What we really need is a user thread to perform the
+ * syscalls as we test.
+ */
+#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS
+ if (call->class->system &&
+ strcmp(call->class->system, "syscalls") == 0)
+ continue;
+#endif
+
+ pr_info("Testing event %s: ", trace_event_name(call));
+
+ /*
+ * If an event is already enabled, someone is using
+ * it and the self test should not be on.
+ */
+ if (file->flags & EVENT_FILE_FL_ENABLED) {
+ pr_warn("Enabled event during self test!\n");
+ WARN_ON_ONCE(1);
+ continue;
+ }
+
+ ftrace_event_enable_disable(file, 1);
+ event_test_stuff();
+ ftrace_event_enable_disable(file, 0);
+
+ pr_cont("OK\n");
+ }
+
+ /* Now test at the sub system level */
+
+ pr_info("Running tests on trace event systems:\n");
+
+ list_for_each_entry(dir, &tr->systems, list) {
+
+ system = dir->subsystem;
+
+ /* the ftrace system is special, skip it */
+ if (strcmp(system->name, "ftrace") == 0)
+ continue;
+
+ pr_info("Testing event system %s: ", system->name);
+
+ ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error enabling system %s\n",
+ system->name);
+ continue;
+ }
+
+ event_test_stuff();
+
+ ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error disabling system %s\n",
+ system->name);
+ continue;
+ }
+
+ pr_cont("OK\n");
+ }
+
+ /* Test with all events enabled */
+
+ pr_info("Running tests on all trace events:\n");
+ pr_info("Testing all events: ");
+
+ ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error enabling all events\n");
+ return;
+ }
+
+ event_test_stuff();
+
+ /* reset sysname */
+ ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warn("error disabling all events\n");
+ return;
+ }
+
+ pr_cont("OK\n");
+}
+
+#ifdef CONFIG_FUNCTION_TRACER
+
+static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
+
+static struct trace_event_file event_trace_file __initdata;
+
+static void __init
+function_test_events_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct ftrace_regs *regs)
+{
+ struct trace_buffer *buffer;
+ struct ring_buffer_event *event;
+ struct ftrace_entry *entry;
+ unsigned int trace_ctx;
+ long disabled;
+ int cpu;
+
+ trace_ctx = tracing_gen_ctx();
+ preempt_disable_notrace();
+ cpu = raw_smp_processor_id();
+ disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
+
+ if (disabled != 1)
+ goto out;
+
+ event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file,
+ TRACE_FN, sizeof(*entry),
+ trace_ctx);
+ if (!event)
+ goto out;
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+ entry->parent_ip = parent_ip;
+
+ event_trigger_unlock_commit(&event_trace_file, buffer, event,
+ entry, trace_ctx);
+ out:
+ atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
+ preempt_enable_notrace();
+}
+
+static struct ftrace_ops trace_ops __initdata =
+{
+ .func = function_test_events_call,
+};
+
+static __init void event_trace_self_test_with_function(void)
+{
+ int ret;
+
+ event_trace_file.tr = top_trace_array();
+ if (WARN_ON(!event_trace_file.tr))
+ return;
+
+ ret = register_ftrace_function(&trace_ops);
+ if (WARN_ON(ret < 0)) {
+ pr_info("Failed to enable function tracer for event tests\n");
+ return;
+ }
+ pr_info("Running tests again, along with the function tracer\n");
+ event_trace_self_tests();
+ unregister_ftrace_function(&trace_ops);
+}
+#else
+static __init void event_trace_self_test_with_function(void)
+{
+}
+#endif
+
+static __init int event_trace_self_tests_init(void)
+{
+ if (!tracing_selftest_disabled) {
+ event_trace_self_tests();
+ event_trace_self_test_with_function();
+ }
+
+ return 0;
+}
+
+late_initcall(event_trace_self_tests_init);
+
+#endif