zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/kernel/trace/trace_events.c b/ap/os/linux/linux-3.4.x/kernel/trace/trace_events.c
new file mode 100644
index 0000000..b56bafe
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/kernel/trace/trace_events.c
@@ -0,0 +1,1766 @@
+/*
+ * 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>.
+ *
+ */
+
+#include <linux/workqueue.h>
+#include <linux/spinlock.h>
+#include <linux/kthread.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+
+#include <asm/setup.h>
+
+#include "trace_output.h"
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM "TRACE_SYSTEM"
+
+DEFINE_MUTEX(event_mutex);
+
+DEFINE_MUTEX(event_storage_mutex);
+EXPORT_SYMBOL_GPL(event_storage_mutex);
+
+char event_storage[EVENT_STORAGE_SIZE];
+EXPORT_SYMBOL_GPL(event_storage);
+
+LIST_HEAD(ftrace_events);
+LIST_HEAD(ftrace_common_fields);
+
+struct list_head *
+trace_get_fields(struct ftrace_event_call *event_call)
+{
+ if (!event_call->class->get_fields)
+ return &event_call->class->fields;
+ return event_call->class->get_fields(event_call);
+}
+
+static int __trace_define_field(struct list_head *head, const char *type,
+ const char *name, int offset, int size,
+ int is_signed, int filter_type)
+{
+ struct ftrace_event_field *field;
+
+ field = kzalloc(sizeof(*field), GFP_KERNEL);
+ if (!field)
+ goto err;
+
+ field->name = kstrdup(name, GFP_KERNEL);
+ if (!field->name)
+ goto err;
+
+ field->type = kstrdup(type, GFP_KERNEL);
+ if (!field->type)
+ goto err;
+
+ if (filter_type == FILTER_OTHER)
+ field->filter_type = filter_assign_type(type);
+ else
+ field->filter_type = filter_type;
+
+ field->offset = offset;
+ field->size = size;
+ field->is_signed = is_signed;
+
+ list_add(&field->link, head);
+
+ return 0;
+
+err:
+ if (field)
+ kfree(field->name);
+ kfree(field);
+
+ return -ENOMEM;
+}
+
+int trace_define_field(struct ftrace_event_call *call, const char *type,
+ const char *name, int offset, int size, int is_signed,
+ int filter_type)
+{
+ struct list_head *head;
+
+ if (WARN_ON(!call->class))
+ return 0;
+
+ head = trace_get_fields(call);
+ return __trace_define_field(head, type, name, offset, size,
+ is_signed, filter_type);
+}
+EXPORT_SYMBOL_GPL(trace_define_field);
+
+#define __common_field(type, item) \
+ ret = __trace_define_field(&ftrace_common_fields, #type, \
+ "common_" #item, \
+ offsetof(typeof(ent), item), \
+ sizeof(ent.item), \
+ is_signed_type(type), FILTER_OTHER); \
+ if (ret) \
+ return ret;
+
+static int trace_define_common_fields(void)
+{
+ int ret;
+ struct trace_entry ent;
+
+ __common_field(unsigned short, type);
+ __common_field(unsigned char, flags);
+ __common_field(unsigned char, preempt_count);
+ __common_field(int, pid);
+ __common_field(unsigned short, migrate_disable);
+ __common_field(unsigned short, padding);
+
+ return ret;
+}
+
+void trace_destroy_fields(struct ftrace_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);
+ kfree(field->type);
+ kfree(field->name);
+ kfree(field);
+ }
+}
+
+int trace_event_raw_init(struct ftrace_event_call *call)
+{
+ int id;
+
+ id = register_ftrace_event(&call->event);
+ if (!id)
+ return -ENODEV;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(trace_event_raw_init);
+
+int ftrace_event_reg(struct ftrace_event_call *call,
+ enum trace_reg type, void *data)
+{
+ switch (type) {
+ case TRACE_REG_REGISTER:
+ return tracepoint_probe_register(call->name,
+ call->class->probe,
+ call);
+ case TRACE_REG_UNREGISTER:
+ tracepoint_probe_unregister(call->name,
+ call->class->probe,
+ call);
+ return 0;
+
+#ifdef CONFIG_PERF_EVENTS
+ case TRACE_REG_PERF_REGISTER:
+ return tracepoint_probe_register(call->name,
+ call->class->perf_probe,
+ call);
+ case TRACE_REG_PERF_UNREGISTER:
+ tracepoint_probe_unregister(call->name,
+ 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(ftrace_event_reg);
+
+void trace_event_enable_cmd_record(bool enable)
+{
+ struct ftrace_event_call *call;
+
+ mutex_lock(&event_mutex);
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (!(call->flags & TRACE_EVENT_FL_ENABLED))
+ continue;
+
+ if (enable) {
+ tracing_start_cmdline_record();
+ call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
+ } else {
+ tracing_stop_cmdline_record();
+ call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
+ }
+ }
+ mutex_unlock(&event_mutex);
+}
+
+static int ftrace_event_enable_disable(struct ftrace_event_call *call,
+ int enable)
+{
+ int ret = 0;
+
+ switch (enable) {
+ case 0:
+ if (call->flags & TRACE_EVENT_FL_ENABLED) {
+ call->flags &= ~TRACE_EVENT_FL_ENABLED;
+ if (call->flags & TRACE_EVENT_FL_RECORDED_CMD) {
+ tracing_stop_cmdline_record();
+ call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
+ }
+ call->class->reg(call, TRACE_REG_UNREGISTER, NULL);
+ }
+ break;
+ case 1:
+ if (!(call->flags & TRACE_EVENT_FL_ENABLED)) {
+ if (trace_flags & TRACE_ITER_RECORD_CMD) {
+ tracing_start_cmdline_record();
+ call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
+ }
+ ret = call->class->reg(call, TRACE_REG_REGISTER, NULL);
+ if (ret) {
+ tracing_stop_cmdline_record();
+ pr_info("event trace: Could not enable event "
+ "%s\n", call->name);
+ break;
+ }
+ call->flags |= TRACE_EVENT_FL_ENABLED;
+ }
+ break;
+ }
+
+ return ret;
+}
+
+static void ftrace_clear_events(void)
+{
+ struct ftrace_event_call *call;
+
+ mutex_lock(&event_mutex);
+ list_for_each_entry(call, &ftrace_events, list) {
+ ftrace_event_enable_disable(call, 0);
+ }
+ mutex_unlock(&event_mutex);
+}
+
+static void __put_system(struct event_subsystem *system)
+{
+ struct event_filter *filter = system->filter;
+
+ WARN_ON_ONCE(system->ref_count == 0);
+ if (--system->ref_count)
+ return;
+
+ if (filter) {
+ kfree(filter->filter_string);
+ kfree(filter);
+ }
+ kfree(system->name);
+ kfree(system);
+}
+
+static void __get_system(struct event_subsystem *system)
+{
+ WARN_ON_ONCE(system->ref_count == 0);
+ system->ref_count++;
+}
+
+static void put_system(struct event_subsystem *system)
+{
+ mutex_lock(&event_mutex);
+ __put_system(system);
+ mutex_unlock(&event_mutex);
+}
+
+/*
+ * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events.
+ */
+static int __ftrace_set_clr_event(const char *match, const char *sub,
+ const char *event, int set)
+{
+ struct ftrace_event_call *call;
+ int ret = -EINVAL;
+
+ mutex_lock(&event_mutex);
+ list_for_each_entry(call, &ftrace_events, list) {
+
+ if (!call->name || !call->class || !call->class->reg)
+ continue;
+
+ if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)
+ continue;
+
+ if (match &&
+ strcmp(match, call->name) != 0 &&
+ strcmp(match, call->class->system) != 0)
+ continue;
+
+ if (sub && strcmp(sub, call->class->system) != 0)
+ continue;
+
+ if (event && strcmp(event, call->name) != 0)
+ continue;
+
+ ftrace_event_enable_disable(call, set);
+
+ ret = 0;
+ }
+ mutex_unlock(&event_mutex);
+
+ return ret;
+}
+
+static int ftrace_set_clr_event(char *buf, int set)
+{
+ char *event = NULL, *sub = NULL, *match;
+
+ /*
+ * 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;
+ }
+
+ return __ftrace_set_clr_event(match, sub, event, set);
+}
+
+/**
+ * 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)
+{
+ return __ftrace_set_clr_event(NULL, system, event, set);
+}
+EXPORT_SYMBOL_GPL(trace_set_clr_event);
+
+/* 128 should be much more than enough */
+#define EVENT_BUF_SIZE 127
+
+static ssize_t
+ftrace_event_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_parser parser;
+ ssize_t read, ret;
+
+ if (!cnt)
+ return 0;
+
+ ret = tracing_update_buffers();
+ if (ret < 0)
+ return ret;
+
+ if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
+ return -ENOMEM;
+
+ read = trace_get_user(&parser, ubuf, cnt, ppos);
+
+ if (read >= 0 && trace_parser_loaded((&parser))) {
+ int set = 1;
+
+ if (*parser.buffer == '!')
+ set = 0;
+
+ parser.buffer[parser.idx] = 0;
+
+ ret = ftrace_set_clr_event(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 ftrace_event_call *call = v;
+
+ (*pos)++;
+
+ list_for_each_entry_continue(call, &ftrace_events, list) {
+ /*
+ * 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)
+ return call;
+ }
+
+ return NULL;
+}
+
+static void *t_start(struct seq_file *m, loff_t *pos)
+{
+ struct ftrace_event_call *call;
+ loff_t l;
+
+ mutex_lock(&event_mutex);
+
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
+ for (l = 0; l <= *pos; ) {
+ call = t_next(m, call, &l);
+ if (!call)
+ break;
+ }
+ return call;
+}
+
+static void *
+s_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct ftrace_event_call *call = v;
+
+ (*pos)++;
+
+ list_for_each_entry_continue(call, &ftrace_events, list) {
+ if (call->flags & TRACE_EVENT_FL_ENABLED)
+ return call;
+ }
+
+ return NULL;
+}
+
+static void *s_start(struct seq_file *m, loff_t *pos)
+{
+ struct ftrace_event_call *call;
+ loff_t l;
+
+ mutex_lock(&event_mutex);
+
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
+ for (l = 0; l <= *pos; ) {
+ call = s_next(m, call, &l);
+ if (!call)
+ break;
+ }
+ return call;
+}
+
+static int t_show(struct seq_file *m, void *v)
+{
+ struct ftrace_event_call *call = v;
+
+ if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
+ seq_printf(m, "%s:", call->class->system);
+ seq_printf(m, "%s\n", call->name);
+
+ return 0;
+}
+
+static void t_stop(struct seq_file *m, void *p)
+{
+ mutex_unlock(&event_mutex);
+}
+
+static int
+ftrace_event_seq_open(struct inode *inode, struct file *file)
+{
+ const struct seq_operations *seq_ops;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_clear_events();
+
+ seq_ops = inode->i_private;
+ return seq_open(file, seq_ops);
+}
+
+static ssize_t
+event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct ftrace_event_call *call = filp->private_data;
+ char *buf;
+
+ if (call->flags & TRACE_EVENT_FL_ENABLED)
+ buf = "1\n";
+ else
+ buf = "0\n";
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
+}
+
+static ssize_t
+event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct ftrace_event_call *call = filp->private_data;
+ 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:
+ mutex_lock(&event_mutex);
+ ret = ftrace_event_enable_disable(call, 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 event_subsystem *system = filp->private_data;
+ struct ftrace_event_call *call;
+ char buf[2];
+ int set = 0;
+ int ret;
+
+ mutex_lock(&event_mutex);
+ list_for_each_entry(call, &ftrace_events, list) {
+ if (!call->name || !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 << !!(call->flags & TRACE_EVENT_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 event_subsystem *system = filp->private_data;
+ 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(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 ftrace_event_call *call = m->private;
+ struct ftrace_event_field *field;
+ struct list_head *common_head = &ftrace_common_fields;
+ struct list_head *head = trace_get_fields(call);
+
+ (*pos)++;
+
+ switch ((unsigned long)v) {
+ case FORMAT_HEADER:
+ if (unlikely(list_empty(common_head)))
+ return NULL;
+
+ field = list_entry(common_head->prev,
+ struct ftrace_event_field, link);
+ return field;
+
+ case FORMAT_FIELD_SEPERATOR:
+ if (unlikely(list_empty(head)))
+ return NULL;
+
+ field = list_entry(head->prev, struct ftrace_event_field, link);
+ return field;
+
+ case FORMAT_PRINTFMT:
+ /* all done */
+ return NULL;
+ }
+
+ field = v;
+ if (field->link.prev == common_head)
+ return (void *)FORMAT_FIELD_SEPERATOR;
+ else if (field->link.prev == head)
+ return (void *)FORMAT_PRINTFMT;
+
+ field = list_entry(field->link.prev, struct ftrace_event_field, link);
+
+ return field;
+}
+
+static void *f_start(struct seq_file *m, loff_t *pos)
+{
+ loff_t l = 0;
+ void *p;
+
+ /* Start by showing the header */
+ if (!*pos)
+ return (void *)FORMAT_HEADER;
+
+ p = (void *)FORMAT_HEADER;
+ do {
+ p = f_next(m, p, &l);
+ } while (p && l < *pos);
+
+ return p;
+}
+
+static int f_show(struct seq_file *m, void *v)
+{
+ struct ftrace_event_call *call = m->private;
+ struct ftrace_event_field *field;
+ const char *array_descriptor;
+
+ switch ((unsigned long)v) {
+ case FORMAT_HEADER:
+ seq_printf(m, "name: %s\n", call->name);
+ seq_printf(m, "ID: %d\n", call->event.type);
+ seq_printf(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 = v;
+
+ /*
+ * 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 (!strncmp(field->type, "__data_loc", 10))
+ 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
+ seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n",
+ (int)(array_descriptor - field->type),
+ field->type, field->name,
+ array_descriptor, field->offset,
+ field->size, !!field->is_signed);
+
+ return 0;
+}
+
+static void f_stop(struct seq_file *m, void *p)
+{
+}
+
+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 ftrace_event_call *call = inode->i_private;
+ struct seq_file *m;
+ int ret;
+
+ ret = seq_open(file, &trace_format_seq_ops);
+ if (ret < 0)
+ return ret;
+
+ m = file->private_data;
+ m->private = call;
+
+ return 0;
+}
+
+static ssize_t
+event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+ struct ftrace_event_call *call = 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);
+ trace_seq_printf(s, "%d\n", call->event.type);
+
+ r = simple_read_from_buffer(ubuf, cnt, ppos,
+ s->buffer, s->len);
+ kfree(s);
+ return r;
+}
+
+static ssize_t
+event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct ftrace_event_call *call = 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);
+
+ print_event_filter(call, s);
+ r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
+
+ kfree(s);
+
+ return r;
+}
+
+static ssize_t
+event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct ftrace_event_call *call = filp->private_data;
+ char *buf;
+ int err;
+
+ if (cnt >= PAGE_SIZE)
+ return -EINVAL;
+
+ buf = (char *)__get_free_page(GFP_TEMPORARY);
+ if (!buf)
+ return -ENOMEM;
+
+ if (copy_from_user(buf, ubuf, cnt)) {
+ free_page((unsigned long) buf);
+ return -EFAULT;
+ }
+ buf[cnt] = '\0';
+
+ err = apply_event_filter(call, buf);
+ free_page((unsigned long) 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 event_subsystem *system = NULL;
+ int ret;
+
+ if (!inode->i_private)
+ goto skip_search;
+
+ /* Make sure the system still exists */
+ mutex_lock(&event_mutex);
+ list_for_each_entry(system, &event_subsystems, list) {
+ if (system == inode->i_private) {
+ /* Don't open systems with no events */
+ if (!system->nr_events) {
+ system = NULL;
+ break;
+ }
+ __get_system(system);
+ break;
+ }
+ }
+ mutex_unlock(&event_mutex);
+
+ if (system != inode->i_private)
+ return -ENODEV;
+
+ skip_search:
+ ret = tracing_open_generic(inode, filp);
+ if (ret < 0 && system)
+ put_system(system);
+
+ return ret;
+}
+
+static int subsystem_release(struct inode *inode, struct file *file)
+{
+ struct event_subsystem *system = inode->i_private;
+
+ if (system)
+ put_system(system);
+
+ return 0;
+}
+
+static ssize_t
+subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct event_subsystem *system = 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);
+
+ print_subsystem_event_filter(system, s);
+ r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, s->len);
+
+ kfree(s);
+
+ return r;
+}
+
+static ssize_t
+subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct event_subsystem *system = filp->private_data;
+ char *buf;
+ int err;
+
+ if (cnt >= PAGE_SIZE)
+ return -EINVAL;
+
+ buf = (char *)__get_free_page(GFP_TEMPORARY);
+ if (!buf)
+ return -ENOMEM;
+
+ if (copy_from_user(buf, ubuf, cnt)) {
+ free_page((unsigned long) buf);
+ return -EFAULT;
+ }
+ buf[cnt] = '\0';
+
+ err = apply_subsystem_event_filter(system, buf);
+ free_page((unsigned long) 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, s->len);
+
+ kfree(s);
+
+ return r;
+}
+
+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 file_operations ftrace_avail_fops = {
+ .open = ftrace_event_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static const struct file_operations ftrace_set_event_fops = {
+ .open = ftrace_event_seq_open,
+ .read = seq_read,
+ .write = ftrace_event_write,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static const struct file_operations ftrace_enable_fops = {
+ .open = tracing_open_generic,
+ .read = event_enable_read,
+ .write = event_enable_write,
+ .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 = {
+ .open = tracing_open_generic,
+ .read = event_id_read,
+ .llseek = default_llseek,
+};
+
+static const struct file_operations ftrace_event_filter_fops = {
+ .open = tracing_open_generic,
+ .read = event_filter_read,
+ .write = event_filter_write,
+ .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_show_header_fops = {
+ .open = tracing_open_generic,
+ .read = show_header,
+ .llseek = default_llseek,
+};
+
+static struct dentry *event_trace_events_dir(void)
+{
+ static struct dentry *d_tracer;
+ static struct dentry *d_events;
+
+ if (d_events)
+ return d_events;
+
+ d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return NULL;
+
+ d_events = debugfs_create_dir("events", d_tracer);
+ if (!d_events)
+ pr_warning("Could not create debugfs "
+ "'events' directory\n");
+
+ return d_events;
+}
+
+static struct dentry *
+event_subsystem_dir(const char *name, struct dentry *d_events)
+{
+ struct event_subsystem *system;
+ struct dentry *entry;
+
+ /* First see if we did not already create this dir */
+ list_for_each_entry(system, &event_subsystems, list) {
+ if (strcmp(system->name, name) == 0) {
+ system->nr_events++;
+ return system->entry;
+ }
+ }
+
+ /* need to create new entry */
+ system = kmalloc(sizeof(*system), GFP_KERNEL);
+ if (!system) {
+ pr_warning("No memory to create event subsystem %s\n",
+ name);
+ return d_events;
+ }
+
+ system->entry = debugfs_create_dir(name, d_events);
+ if (!system->entry) {
+ pr_warning("Could not create event subsystem %s\n",
+ name);
+ kfree(system);
+ return d_events;
+ }
+
+ system->nr_events = 1;
+ system->ref_count = 1;
+ system->name = kstrdup(name, GFP_KERNEL);
+ if (!system->name) {
+ debugfs_remove(system->entry);
+ kfree(system);
+ return d_events;
+ }
+
+ list_add(&system->list, &event_subsystems);
+
+ system->filter = NULL;
+
+ system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL);
+ if (!system->filter) {
+ pr_warning("Could not allocate filter for subsystem "
+ "'%s'\n", name);
+ return system->entry;
+ }
+
+ entry = debugfs_create_file("filter", 0644, system->entry, system,
+ &ftrace_subsystem_filter_fops);
+ if (!entry) {
+ kfree(system->filter);
+ system->filter = NULL;
+ pr_warning("Could not create debugfs "
+ "'%s/filter' entry\n", name);
+ }
+
+ trace_create_file("enable", 0644, system->entry, system,
+ &ftrace_system_enable_fops);
+
+ return system->entry;
+}
+
+static int
+event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
+ const struct file_operations *id,
+ const struct file_operations *enable,
+ const struct file_operations *filter,
+ const struct file_operations *format)
+{
+ struct list_head *head;
+ int ret;
+
+ /*
+ * If the trace point header did not define TRACE_SYSTEM
+ * then the system would be called "TRACE_SYSTEM".
+ */
+ if (strcmp(call->class->system, TRACE_SYSTEM) != 0)
+ d_events = event_subsystem_dir(call->class->system, d_events);
+
+ call->dir = debugfs_create_dir(call->name, d_events);
+ if (!call->dir) {
+ pr_warning("Could not create debugfs "
+ "'%s' directory\n", call->name);
+ return -1;
+ }
+
+ if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE))
+ trace_create_file("enable", 0644, call->dir, call,
+ enable);
+
+#ifdef CONFIG_PERF_EVENTS
+ if (call->event.type && call->class->reg)
+ trace_create_file("id", 0444, call->dir, call,
+ id);
+#endif
+
+ /*
+ * 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)) {
+ ret = call->class->define_fields(call);
+ if (ret < 0) {
+ pr_warning("Could not initialize trace point"
+ " events/%s\n", call->name);
+ return ret;
+ }
+ }
+ trace_create_file("filter", 0644, call->dir, call,
+ filter);
+
+ trace_create_file("format", 0444, call->dir, call,
+ format);
+
+ return 0;
+}
+
+static int
+__trace_add_event_call(struct ftrace_event_call *call, struct module *mod,
+ const struct file_operations *id,
+ const struct file_operations *enable,
+ const struct file_operations *filter,
+ const struct file_operations *format)
+{
+ struct dentry *d_events;
+ int ret;
+
+ /* The linker may leave blanks */
+ if (!call->name)
+ return -EINVAL;
+
+ if (call->class->raw_init) {
+ ret = call->class->raw_init(call);
+ if (ret < 0) {
+ if (ret != -ENOSYS)
+ pr_warning("Could not initialize trace events/%s\n",
+ call->name);
+ return ret;
+ }
+ }
+
+ d_events = event_trace_events_dir();
+ if (!d_events)
+ return -ENOENT;
+
+ ret = event_create_dir(call, d_events, id, enable, filter, format);
+ if (!ret)
+ list_add(&call->list, &ftrace_events);
+ call->mod = mod;
+
+ return ret;
+}
+
+/* Add an additional event_call dynamically */
+int trace_add_event_call(struct ftrace_event_call *call)
+{
+ int ret;
+ mutex_lock(&event_mutex);
+ ret = __trace_add_event_call(call, NULL, &ftrace_event_id_fops,
+ &ftrace_enable_fops,
+ &ftrace_event_filter_fops,
+ &ftrace_event_format_fops);
+ mutex_unlock(&event_mutex);
+ return ret;
+}
+
+static void remove_subsystem_dir(const char *name)
+{
+ struct event_subsystem *system;
+
+ if (strcmp(name, TRACE_SYSTEM) == 0)
+ return;
+
+ list_for_each_entry(system, &event_subsystems, list) {
+ if (strcmp(system->name, name) == 0) {
+ if (!--system->nr_events) {
+ debugfs_remove_recursive(system->entry);
+ list_del(&system->list);
+ __put_system(system);
+ }
+ break;
+ }
+ }
+}
+
+/*
+ * Must be called under locking both of event_mutex and trace_event_mutex.
+ */
+static void __trace_remove_event_call(struct ftrace_event_call *call)
+{
+ ftrace_event_enable_disable(call, 0);
+ if (call->event.funcs)
+ __unregister_ftrace_event(&call->event);
+ debugfs_remove_recursive(call->dir);
+ list_del(&call->list);
+ trace_destroy_fields(call);
+ destroy_preds(call);
+ remove_subsystem_dir(call->class->system);
+}
+
+/* Remove an event_call */
+void trace_remove_event_call(struct ftrace_event_call *call)
+{
+ mutex_lock(&event_mutex);
+ down_write(&trace_event_mutex);
+ __trace_remove_event_call(call);
+ up_write(&trace_event_mutex);
+ mutex_unlock(&event_mutex);
+}
+
+#define for_each_event(event, start, end) \
+ for (event = start; \
+ (unsigned long)event < (unsigned long)end; \
+ event++)
+
+#ifdef CONFIG_MODULES
+
+static LIST_HEAD(ftrace_module_file_list);
+
+/*
+ * Modules must own their file_operations to keep up with
+ * reference counting.
+ */
+struct ftrace_module_file_ops {
+ struct list_head list;
+ struct module *mod;
+ struct file_operations id;
+ struct file_operations enable;
+ struct file_operations format;
+ struct file_operations filter;
+};
+
+static struct ftrace_module_file_ops *
+trace_create_file_ops(struct module *mod)
+{
+ struct ftrace_module_file_ops *file_ops;
+
+ /*
+ * This is a bit of a PITA. To allow for correct reference
+ * counting, modules must "own" their file_operations.
+ * To do this, we allocate the file operations that will be
+ * used in the event directory.
+ */
+
+ file_ops = kmalloc(sizeof(*file_ops), GFP_KERNEL);
+ if (!file_ops)
+ return NULL;
+
+ file_ops->mod = mod;
+
+ file_ops->id = ftrace_event_id_fops;
+ file_ops->id.owner = mod;
+
+ file_ops->enable = ftrace_enable_fops;
+ file_ops->enable.owner = mod;
+
+ file_ops->filter = ftrace_event_filter_fops;
+ file_ops->filter.owner = mod;
+
+ file_ops->format = ftrace_event_format_fops;
+ file_ops->format.owner = mod;
+
+ list_add(&file_ops->list, &ftrace_module_file_list);
+
+ return file_ops;
+}
+
+static void trace_module_add_events(struct module *mod)
+{
+ struct ftrace_module_file_ops *file_ops = NULL;
+ struct ftrace_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;
+
+ if (start == end)
+ return;
+
+ file_ops = trace_create_file_ops(mod);
+ if (!file_ops)
+ return;
+
+ for_each_event(call, start, end) {
+ __trace_add_event_call(*call, mod,
+ &file_ops->id, &file_ops->enable,
+ &file_ops->filter, &file_ops->format);
+ }
+}
+
+static void trace_module_remove_events(struct module *mod)
+{
+ struct ftrace_module_file_ops *file_ops;
+ struct ftrace_event_call *call, *p;
+ bool found = false;
+
+ down_write(&trace_event_mutex);
+ list_for_each_entry_safe(call, p, &ftrace_events, list) {
+ if (call->mod == mod) {
+ found = true;
+ __trace_remove_event_call(call);
+ }
+ }
+
+ /* Now free the file_operations */
+ list_for_each_entry(file_ops, &ftrace_module_file_list, list) {
+ if (file_ops->mod == mod)
+ break;
+ }
+ if (&file_ops->list != &ftrace_module_file_list) {
+ list_del(&file_ops->list);
+ kfree(file_ops);
+ }
+
+ /*
+ * It is safest to reset the ring buffer if the module being unloaded
+ * registered any events.
+ */
+ if (found)
+ tracing_reset_current_online_cpus();
+ up_write(&trace_event_mutex);
+}
+
+static int trace_module_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+
+ mutex_lock(&event_mutex);
+ switch (val) {
+ case MODULE_STATE_COMING:
+ trace_module_add_events(mod);
+ break;
+ case MODULE_STATE_GOING:
+ trace_module_remove_events(mod);
+ break;
+ }
+ mutex_unlock(&event_mutex);
+
+ return 0;
+}
+#else
+static int trace_module_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ return 0;
+}
+#endif /* CONFIG_MODULES */
+
+static struct notifier_block trace_module_nb = {
+ .notifier_call = trace_module_notify,
+ .priority = 0,
+};
+
+extern struct ftrace_event_call *__start_ftrace_events[];
+extern struct ftrace_event_call *__stop_ftrace_events[];
+
+static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata;
+
+static __init int setup_trace_event(char *str)
+{
+ strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE);
+ ring_buffer_expanded = 1;
+ tracing_selftest_disabled = 1;
+
+ return 1;
+}
+__setup("trace_event=", setup_trace_event);
+
+static __init int event_trace_init(void)
+{
+ struct ftrace_event_call **call;
+ struct dentry *d_tracer;
+ struct dentry *entry;
+ struct dentry *d_events;
+ int ret;
+ char *buf = bootup_event_buf;
+ char *token;
+
+ d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return 0;
+
+ entry = debugfs_create_file("available_events", 0444, d_tracer,
+ (void *)&show_event_seq_ops,
+ &ftrace_avail_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'available_events' entry\n");
+
+ entry = debugfs_create_file("set_event", 0644, d_tracer,
+ (void *)&show_set_event_seq_ops,
+ &ftrace_set_event_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_event' entry\n");
+
+ d_events = event_trace_events_dir();
+ if (!d_events)
+ return 0;
+
+ /* ring buffer internal formats */
+ trace_create_file("header_page", 0444, d_events,
+ ring_buffer_print_page_header,
+ &ftrace_show_header_fops);
+
+ trace_create_file("header_event", 0444, d_events,
+ ring_buffer_print_entry_header,
+ &ftrace_show_header_fops);
+
+ trace_create_file("enable", 0644, d_events,
+ NULL, &ftrace_system_enable_fops);
+
+ if (trace_define_common_fields())
+ pr_warning("tracing: Failed to allocate common fields");
+
+ for_each_event(call, __start_ftrace_events, __stop_ftrace_events) {
+ __trace_add_event_call(*call, NULL, &ftrace_event_id_fops,
+ &ftrace_enable_fops,
+ &ftrace_event_filter_fops,
+ &ftrace_event_format_fops);
+ }
+
+ while (true) {
+ token = strsep(&buf, ",");
+
+ if (!token)
+ break;
+ if (!*token)
+ continue;
+
+ ret = ftrace_set_clr_event(token, 1);
+ if (ret)
+ pr_warning("Failed to enable trace event: %s\n", token);
+ }
+
+ ret = register_module_notifier(&trace_module_nb);
+ if (ret)
+ pr_warning("Failed to register trace events module notifier\n");
+
+ return 0;
+}
+fs_initcall(event_trace_init);
+
+#ifdef CONFIG_FTRACE_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();
+
+ 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 ftrace_event_call *call;
+ struct event_subsystem *system;
+ int ret;
+
+ pr_info("Running tests on trace events:\n");
+
+ list_for_each_entry(call, &ftrace_events, list) {
+
+ /* 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: ", call->name);
+
+ /*
+ * If an event is already enabled, someone is using
+ * it and the self test should not be on.
+ */
+ if (call->flags & TRACE_EVENT_FL_ENABLED) {
+ pr_warning("Enabled event during self test!\n");
+ WARN_ON_ONCE(1);
+ continue;
+ }
+
+ ftrace_event_enable_disable(call, 1);
+ event_test_stuff();
+ ftrace_event_enable_disable(call, 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(system, &event_subsystems, list) {
+
+ /* 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(NULL, system->name, NULL, 1);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("error enabling system %s\n",
+ system->name);
+ continue;
+ }
+
+ event_test_stuff();
+
+ ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0);
+ if (WARN_ON_ONCE(ret))
+ pr_warning("error disabling system %s\n",
+ system->name);
+
+ 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(NULL, NULL, NULL, 1);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("error enabling all events\n");
+ return;
+ }
+
+ event_test_stuff();
+
+ /* reset sysname */
+ ret = __ftrace_set_clr_event(NULL, NULL, NULL, 0);
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("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 void
+function_test_events_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ struct ftrace_entry *entry;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ pc = preempt_count();
+ preempt_disable_notrace();
+ cpu = raw_smp_processor_id();
+ disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu));
+
+ if (disabled != 1)
+ goto out;
+
+ local_save_flags(flags);
+
+ event = trace_current_buffer_lock_reserve(&buffer,
+ TRACE_FN, sizeof(*entry),
+ flags, pc);
+ if (!event)
+ goto out;
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+ entry->parent_ip = parent_ip;
+
+ trace_nowake_buffer_unlock_commit(buffer, event, flags, pc);
+
+ 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;
+ 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