+static int __init ftrace_dyn_table_alloc(void)
+{
+ struct ftrace_page *pg;
+ int cnt;
+ int i;
+
+ /* allocate a few pages */
+ ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!ftrace_pages_start)
+ return -1;
+
+ /*
+ * Allocate a few more pages.
+ *
+ * TODO: have some parser search vmlinux before
+ * final linking to find all calls to ftrace.
+ * Then we can:
+ * a) know how many pages to allocate.
+ * and/or
+ * b) set up the table then.
+ *
+ * The dynamic code is still necessary for
+ * modules.
+ */
+
+ pg = ftrace_pages = ftrace_pages_start;
+
+ cnt = NR_TO_INIT / ENTRIES_PER_PAGE;
+
+ for (i = 0; i < cnt; i++) {
+ pg->next = (void *)get_zeroed_page(GFP_KERNEL);
+
+ /* If we fail, we'll try later anyway */
+ if (!pg->next)
+ break;
+
+ pg = pg->next;
+ }
+
+ return 0;
+}
+
+enum {
+ FTRACE_ITER_FILTER = (1 << 0),
+ FTRACE_ITER_CONT = (1 << 1),
+ FTRACE_ITER_NOTRACE = (1 << 2),
+ FTRACE_ITER_FAILURES = (1 << 3),
+};
+
+#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
+
+struct ftrace_iterator {
+ loff_t pos;
+ struct ftrace_page *pg;
+ unsigned idx;
+ unsigned flags;
+ unsigned char buffer[FTRACE_BUFF_MAX+1];
+ unsigned buffer_idx;
+ unsigned filtered;
+};
+
+static void *
+t_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ struct dyn_ftrace *rec = NULL;
+
+ (*pos)++;
+
+ retry:
+ if (iter->idx >= iter->pg->index) {
+ if (iter->pg->next) {
+ iter->pg = iter->pg->next;
+ iter->idx = 0;
+ goto retry;
+ }
+ } else {
+ rec = &iter->pg->records[iter->idx++];
+ if ((!(iter->flags & FTRACE_ITER_FAILURES) &&
+ (rec->flags & FTRACE_FL_FAILED)) ||
+
+ ((iter->flags & FTRACE_ITER_FAILURES) &&
+ (!(rec->flags & FTRACE_FL_FAILED) ||
+ (rec->flags & FTRACE_FL_FREE))) ||
+
+ ((iter->flags & FTRACE_ITER_FILTER) &&
+ !(rec->flags & FTRACE_FL_FILTER)) ||
+
+ ((iter->flags & FTRACE_ITER_NOTRACE) &&
+ !(rec->flags & FTRACE_FL_NOTRACE))) {
+ rec = NULL;
+ goto retry;
+ }
+ }
+
+ iter->pos = *pos;
+
+ return rec;
+}
+
+static void *t_start(struct seq_file *m, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ void *p = NULL;
+ loff_t l = -1;
+
+ if (*pos != iter->pos) {
+ for (p = t_next(m, p, &l); p && l < *pos; p = t_next(m, p, &l))
+ ;
+ } else {
+ l = *pos;
+ p = t_next(m, p, &l);
+ }
+
+ return p;
+}
+
+static void t_stop(struct seq_file *m, void *p)
+{
+}
+
+static int t_show(struct seq_file *m, void *v)
+{
+ struct dyn_ftrace *rec = v;
+ char str[KSYM_SYMBOL_LEN];
+
+ if (!rec)
+ return 0;
+
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+
+ seq_printf(m, "%s\n", str);
+
+ return 0;
+}
+
+static struct seq_operations show_ftrace_seq_ops = {
+ .start = t_start,
+ .next = t_next,
+ .stop = t_stop,
+ .show = t_show,
+};
+
+static int
+ftrace_avail_open(struct inode *inode, struct file *file)
+{
+ struct ftrace_iterator *iter;
+ int ret;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ iter->pg = ftrace_pages_start;
+ iter->pos = -1;
+
+ ret = seq_open(file, &show_ftrace_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+
+ m->private = iter;
+ } else {
+ kfree(iter);
+ }
+
+ return ret;
+}
+
+int ftrace_avail_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = (struct seq_file *)file->private_data;
+ struct ftrace_iterator *iter = m->private;
+
+ seq_release(inode, file);
+ kfree(iter);
+
+ return 0;
+}
+
+static int
+ftrace_failures_open(struct inode *inode, struct file *file)
+{
+ int ret;
+ struct seq_file *m;
+ struct ftrace_iterator *iter;
+
+ ret = ftrace_avail_open(inode, file);
+ if (!ret) {
+ m = (struct seq_file *)file->private_data;
+ iter = (struct ftrace_iterator *)m->private;
+ iter->flags = FTRACE_ITER_FAILURES;
+ }
+
+ return ret;
+}
+
+
+static void ftrace_filter_reset(int enable)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+ unsigned i;
+
+ /* keep kstop machine from running */
+ preempt_disable();
+ if (enable)
+ ftrace_filtered = 0;
+ pg = ftrace_pages_start;
+ while (pg) {
+ for (i = 0; i < pg->index; i++) {
+ rec = &pg->records[i];
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+ rec->flags &= ~type;
+ }
+ pg = pg->next;
+ }
+ preempt_enable();
+}
+
+static int
+ftrace_regex_open(struct inode *inode, struct file *file, int enable)
+{
+ struct ftrace_iterator *iter;
+ int ret = 0;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ mutex_lock(&ftrace_regex_lock);
+ if ((file->f_mode & FMODE_WRITE) &&
+ !(file->f_flags & O_APPEND))
+ ftrace_filter_reset(enable);
+
+ if (file->f_mode & FMODE_READ) {
+ iter->pg = ftrace_pages_start;
+ iter->pos = -1;
+ iter->flags = enable ? FTRACE_ITER_FILTER :
+ FTRACE_ITER_NOTRACE;
+
+ ret = seq_open(file, &show_ftrace_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = iter;
+ } else
+ kfree(iter);
+ } else
+ file->private_data = iter;
+ mutex_unlock(&ftrace_regex_lock);
+
+ return ret;
+}
+
+static int
+ftrace_filter_open(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_open(inode, file, 1);
+}
+
+static int
+ftrace_notrace_open(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_open(inode, file, 0);
+}
+
+static ssize_t
+ftrace_regex_read(struct file *file, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ if (file->f_mode & FMODE_READ)
+ return seq_read(file, ubuf, cnt, ppos);
+ else
+ return -EPERM;
+}
+
+static loff_t
+ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t ret;
+
+ if (file->f_mode & FMODE_READ)
+ ret = seq_lseek(file, offset, origin);
+ else
+ file->f_pos = ret = 1;
+
+ return ret;
+}
+
+enum {
+ MATCH_FULL,
+ MATCH_FRONT_ONLY,
+ MATCH_MIDDLE_ONLY,
+ MATCH_END_ONLY,
+};
+
+static void
+ftrace_match(unsigned char *buff, int len, int enable)
+{
+ char str[KSYM_SYMBOL_LEN];
+ char *search = NULL;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int type = MATCH_FULL;
+ unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+ unsigned i, match = 0, search_len = 0;
+
+ for (i = 0; i < len; i++) {
+ if (buff[i] == '*') {
+ if (!i) {
+ search = buff + i + 1;
+ type = MATCH_END_ONLY;
+ search_len = len - (i + 1);
+ } else {
+ if (type == MATCH_END_ONLY) {
+ type = MATCH_MIDDLE_ONLY;
+ } else {
+ match = i;
+ type = MATCH_FRONT_ONLY;
+ }
+ buff[i] = 0;
+ break;
+ }
+ }
+ }
+
+ /* keep kstop machine from running */
+ preempt_disable();
+ if (enable)
+ ftrace_filtered = 1;
+ pg = ftrace_pages_start;
+ while (pg) {
+ for (i = 0; i < pg->index; i++) {
+ int matched = 0;
+ char *ptr;
+
+ rec = &pg->records[i];
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ switch (type) {
+ case MATCH_FULL:
+ if (strcmp(str, buff) == 0)
+ matched = 1;
+ break;
+ case MATCH_FRONT_ONLY:
+ if (memcmp(str, buff, match) == 0)
+ matched = 1;
+ break;
+ case MATCH_MIDDLE_ONLY:
+ if (strstr(str, search))
+ matched = 1;
+ break;
+ case MATCH_END_ONLY:
+ ptr = strstr(str, search);
+ if (ptr && (ptr[search_len] == 0))
+ matched = 1;
+ break;
+ }
+ if (matched)
+ rec->flags |= flag;
+ }
+ pg = pg->next;
+ }
+ preempt_enable();
+}
+
+static ssize_t
+ftrace_regex_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos, int enable)
+{
+ struct ftrace_iterator *iter;
+ char ch;
+ size_t read = 0;
+ ssize_t ret;
+
+ if (!cnt || cnt < 0)
+ return 0;
+
+ mutex_lock(&ftrace_regex_lock);
+
+ if (file->f_mode & FMODE_READ) {
+ struct seq_file *m = file->private_data;
+ iter = m->private;
+ } else
+ iter = file->private_data;
+
+ if (!*ppos) {
+ iter->flags &= ~FTRACE_ITER_CONT;
+ iter->buffer_idx = 0;
+ }
+
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+
+ if (!(iter->flags & ~FTRACE_ITER_CONT)) {
+ /* skip white space */
+ while (cnt && isspace(ch)) {
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ if (isspace(ch)) {
+ file->f_pos += read;
+ ret = read;
+ goto out;
+ }
+
+ iter->buffer_idx = 0;
+ }
+
+ while (cnt && !isspace(ch)) {
+ if (iter->buffer_idx < FTRACE_BUFF_MAX)
+ iter->buffer[iter->buffer_idx++] = ch;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ if (isspace(ch)) {
+ iter->filtered++;
+ iter->buffer[iter->buffer_idx] = 0;
+ ftrace_match(iter->buffer, iter->buffer_idx, enable);
+ iter->buffer_idx = 0;
+ } else
+ iter->flags |= FTRACE_ITER_CONT;
+
+
+ file->f_pos += read;
+
+ ret = read;
+ out:
+ mutex_unlock(&ftrace_regex_lock);
+
+ return ret;
+}
+
+static ssize_t
+ftrace_filter_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return ftrace_regex_write(file, ubuf, cnt, ppos, 1);
+}
+
+static ssize_t
+ftrace_notrace_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return ftrace_regex_write(file, ubuf, cnt, ppos, 0);
+}
+
+static void
+ftrace_set_regex(unsigned char *buf, int len, int reset, int enable)
+{
+ if (unlikely(ftrace_disabled))
+ return;
+
+ mutex_lock(&ftrace_regex_lock);
+ if (reset)
+ ftrace_filter_reset(enable);
+ if (buf)
+ ftrace_match(buf, len, enable);
+ mutex_unlock(&ftrace_regex_lock);
+}
+
+/**
+ * ftrace_set_filter - set a function to filter on in ftrace
+ * @buf - the string that holds the function filter text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Filters denote which functions should be enabled when tracing is enabled.
+ * If @buf is NULL and reset is set, all functions will be enabled for tracing.
+ */
+void ftrace_set_filter(unsigned char *buf, int len, int reset)
+{
+ ftrace_set_regex(buf, len, reset, 1);
+}
+
+/**
+ * ftrace_set_notrace - set a function to not trace in ftrace
+ * @buf - the string that holds the function notrace text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Notrace Filters denote which functions should not be enabled when tracing
+ * is enabled. If @buf is NULL and reset is set, all functions will be enabled
+ * for tracing.
+ */
+void ftrace_set_notrace(unsigned char *buf, int len, int reset)
+{
+ ftrace_set_regex(buf, len, reset, 0);
+}
+
+static int
+ftrace_regex_release(struct inode *inode, struct file *file, int enable)
+{
+ struct seq_file *m = (struct seq_file *)file->private_data;
+ struct ftrace_iterator *iter;
+
+ mutex_lock(&ftrace_regex_lock);
+ if (file->f_mode & FMODE_READ) {
+ iter = m->private;
+
+ seq_release(inode, file);
+ } else
+ iter = file->private_data;
+
+ if (iter->buffer_idx) {
+ iter->filtered++;
+ iter->buffer[iter->buffer_idx] = 0;
+ ftrace_match(iter->buffer, iter->buffer_idx, enable);
+ }
+
+ mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftraced_lock);
+ if (iter->filtered && ftraced_suspend && ftrace_enabled)
+ ftrace_run_update_code(FTRACE_ENABLE_CALLS);
+ mutex_unlock(&ftraced_lock);
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ kfree(iter);
+ mutex_unlock(&ftrace_regex_lock);
+ return 0;
+}
+
+static int
+ftrace_filter_release(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_release(inode, file, 1);
+}
+
+static int
+ftrace_notrace_release(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_release(inode, file, 0);
+}
+
+static ssize_t
+ftraced_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ /* don't worry about races */
+ char *buf = ftraced_stop ? "disabled\n" : "enabled\n";
+ int r = strlen(buf);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+ftraced_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ if (strncmp(buf, "enable", 6) == 0)
+ val = 1;
+ else if (strncmp(buf, "disable", 7) == 0)
+ val = 0;
+ else {
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ val = !!val;
+ }
+
+ if (val)
+ ftrace_enable_daemon();
+ else
+ ftrace_disable_daemon();
+
+ filp->f_pos += cnt;
+
+ return cnt;
+}
+
+static struct file_operations ftrace_avail_fops = {
+ .open = ftrace_avail_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = ftrace_avail_release,
+};
+
+static struct file_operations ftrace_failures_fops = {
+ .open = ftrace_failures_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = ftrace_avail_release,
+};
+
+static struct file_operations ftrace_filter_fops = {
+ .open = ftrace_filter_open,
+ .read = ftrace_regex_read,
+ .write = ftrace_filter_write,
+ .llseek = ftrace_regex_lseek,
+ .release = ftrace_filter_release,
+};
+
+static struct file_operations ftrace_notrace_fops = {
+ .open = ftrace_notrace_open,
+ .read = ftrace_regex_read,
+ .write = ftrace_notrace_write,
+ .llseek = ftrace_regex_lseek,
+ .release = ftrace_notrace_release,
+};
+
+static struct file_operations ftraced_fops = {
+ .open = tracing_open_generic,
+ .read = ftraced_read,
+ .write = ftraced_write,
+};
+
+/**
+ * ftrace_force_update - force an update to all recording ftrace functions
+ */
+int ftrace_force_update(void)
+{
+ int ret = 0;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftraced_lock);
+
+ /*
+ * If ftraced_trigger is not set, then there is nothing
+ * to update.
+ */
+ if (ftraced_trigger && !ftrace_update_code())
+ ret = -EBUSY;
+
+ mutex_unlock(&ftraced_lock);
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ return ret;
+}
+
+static void ftrace_force_shutdown(void)
+{
+ struct task_struct *task;
+ int command = FTRACE_DISABLE_CALLS | FTRACE_UPDATE_TRACE_FUNC;
+
+ mutex_lock(&ftraced_lock);
+ task = ftraced_task;
+ ftraced_task = NULL;
+ ftraced_suspend = -1;
+ ftrace_run_update_code(command);
+ mutex_unlock(&ftraced_lock);
+
+ if (task)
+ kthread_stop(task);
+}
+
+static __init int ftrace_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ d_tracer = tracing_init_dentry();
+
+ entry = debugfs_create_file("available_filter_functions", 0444,
+ d_tracer, NULL, &ftrace_avail_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'available_filter_functions' entry\n");
+
+ entry = debugfs_create_file("failures", 0444,
+ d_tracer, NULL, &ftrace_failures_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'failures' entry\n");
+
+ entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer,
+ NULL, &ftrace_filter_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_ftrace_filter' entry\n");
+
+ entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer,
+ NULL, &ftrace_notrace_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_ftrace_notrace' entry\n");
+
+ entry = debugfs_create_file("ftraced_enabled", 0644, d_tracer,
+ NULL, &ftraced_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'ftraced_enabled' entry\n");
+ return 0;
+}
+
+fs_initcall(ftrace_init_debugfs);
+
+static int __init ftrace_dynamic_init(void)