#include <linux/stop_machine.h>
#include <linux/clocksource.h>
#include <linux/kallsyms.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
#include <linux/kthread.h>
#include <linux/hardirq.h>
#include <linux/ftrace.h>
-#include <linux/module.h>
+#include <linux/uaccess.h>
#include <linux/sysctl.h>
#include <linux/hash.h>
+#include <linux/ctype.h>
#include <linux/list.h>
#include "trace.h"
FTRACE_DISABLE_MCOUNT = (1 << 4),
};
+static int ftrace_filtered;
+
static struct hlist_head ftrace_hash[FTRACE_HASHSIZE];
static DEFINE_PER_CPU(int, ftrace_shutdown_disable_cpu);
static DEFINE_SPINLOCK(ftrace_shutdown_lock);
static DEFINE_MUTEX(ftraced_lock);
+static DEFINE_MUTEX(ftrace_filter_lock);
struct ftrace_page {
struct ftrace_page *next;
#define FTRACE_ADDR ((long)(&ftrace_caller))
#define MCOUNT_ADDR ((long)(&mcount))
-static void notrace ftrace_replace_code(int saved)
+static void notrace
+__ftrace_replace_code(struct dyn_ftrace *rec,
+ unsigned char *old, unsigned char *new, int enable)
+{
+ unsigned long ip;
+ int failed;
+
+ ip = rec->ip;
+
+ if (ftrace_filtered && enable) {
+ unsigned long fl;
+ /*
+ * If filtering is on:
+ *
+ * If this record is set to be filtered and
+ * is enabled then do nothing.
+ *
+ * If this record is set to be filtered and
+ * it is not enabled, enable it.
+ *
+ * If this record is not set to be filtered
+ * and it is not enabled do nothing.
+ *
+ * If this record is not set to be filtered and
+ * it is enabled, disable it.
+ */
+ fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_ENABLED);
+
+ if ((fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) ||
+ (fl == 0))
+ return;
+
+ /*
+ * If it is enabled disable it,
+ * otherwise enable it!
+ */
+ if (fl == FTRACE_FL_ENABLED) {
+ /* swap new and old */
+ new = old;
+ old = ftrace_call_replace(ip, FTRACE_ADDR);
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ } else {
+ new = ftrace_call_replace(ip, FTRACE_ADDR);
+ rec->flags |= FTRACE_FL_ENABLED;
+ }
+ } else {
+
+ if (enable)
+ new = ftrace_call_replace(ip, FTRACE_ADDR);
+ else
+ old = ftrace_call_replace(ip, FTRACE_ADDR);
+
+ if (enable) {
+ if (rec->flags & FTRACE_FL_ENABLED)
+ return;
+ rec->flags |= FTRACE_FL_ENABLED;
+ } else {
+ if (!(rec->flags & FTRACE_FL_ENABLED))
+ return;
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ }
+ }
+
+ failed = ftrace_modify_code(ip, old, new);
+ if (failed)
+ rec->flags |= FTRACE_FL_FAILED;
+}
+
+static void notrace ftrace_replace_code(int enable)
{
unsigned char *new = NULL, *old = NULL;
struct dyn_ftrace *rec;
struct ftrace_page *pg;
- unsigned long ip;
- int failed;
int i;
- if (saved)
+ if (enable)
old = ftrace_nop_replace();
else
new = ftrace_nop_replace();
if (rec->flags & FTRACE_FL_FAILED)
continue;
- ip = rec->ip;
-
- if (saved)
- new = ftrace_call_replace(ip, FTRACE_ADDR);
- else
- old = ftrace_call_replace(ip, FTRACE_ADDR);
-
- failed = ftrace_modify_code(ip, old, new);
- if (failed)
- rec->flags |= FTRACE_FL_FAILED;
+ __ftrace_replace_code(rec, old, new, enable);
}
}
}
return 0;
}
+enum {
+ FTRACE_ITER_FILTER = (1 << 0),
+ FTRACE_ITER_CONT = (1 << 1),
+};
+
+#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 notrace *
+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 ((rec->flags & FTRACE_FL_FAILED) ||
+ ((iter->flags & FTRACE_ITER_FILTER) &&
+ !(rec->flags & FTRACE_FL_FILTER))) {
+ 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 notrace
+ftrace_avail_open(struct inode *inode, struct file *file)
+{
+ struct ftrace_iterator *iter;
+ int ret;
+
+ 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 void notrace ftrace_filter_reset(void)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ unsigned i;
+
+ /* keep kstop machine from running */
+ preempt_disable();
+ 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 &= ~FTRACE_FL_FILTER;
+ }
+ pg = pg->next;
+ }
+ preempt_enable();
+}
+
+static int notrace
+ftrace_filter_open(struct inode *inode, struct file *file)
+{
+ struct ftrace_iterator *iter;
+ int ret = 0;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ mutex_lock(&ftrace_filter_lock);
+ if ((file->f_mode & FMODE_WRITE) &&
+ !(file->f_flags & O_APPEND))
+ ftrace_filter_reset();
+
+ if (file->f_mode & FMODE_READ) {
+ iter->pg = ftrace_pages_start;
+ iter->pos = -1;
+ iter->flags = FTRACE_ITER_FILTER;
+
+ 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_filter_lock);
+
+ return ret;
+}
+
+static ssize_t notrace
+ftrace_filter_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 notrace
+ftrace_filter_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 notrace
+ftrace_match(unsigned char *buff, int len)
+{
+ char str[KSYM_SYMBOL_LEN];
+ char *search = NULL;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int type = MATCH_FULL;
+ 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();
+ 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 |= FTRACE_FL_FILTER;
+ }
+ pg = pg->next;
+ }
+ preempt_enable();
+}
+
+static ssize_t notrace
+ftrace_filter_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct ftrace_iterator *iter;
+ char ch;
+ size_t read = 0;
+ ssize_t ret;
+
+ if (!cnt || cnt < 0)
+ return 0;
+
+ mutex_lock(&ftrace_filter_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);
+ iter->buffer_idx = 0;
+ } else
+ iter->flags |= FTRACE_ITER_CONT;
+
+
+ file->f_pos += read;
+
+ ret = read;
+ out:
+ mutex_unlock(&ftrace_filter_lock);
+
+ return ret;
+}
+
+static int notrace
+ftrace_filter_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = (struct seq_file *)file->private_data;
+ struct ftrace_iterator *iter;
+
+ mutex_lock(&ftrace_filter_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);
+ }
+
+ 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_filter_lock);
+ return 0;
+}
+
+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_filter_fops = {
+ .open = ftrace_filter_open,
+ .read = ftrace_filter_read,
+ .write = ftrace_filter_write,
+ .llseek = ftrace_filter_lseek,
+ .release = ftrace_filter_release,
+};
+
+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("set_ftrace_filter", 0644, d_tracer,
+ NULL, &ftrace_filter_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_ftrace_filter' entry\n");
+ return 0;
+}
+
+fs_initcall(ftrace_init_debugfs);
+
static int __init notrace ftrace_dynamic_init(void)
{
struct task_struct *p;
notrace int
ftrace_enable_sysctl(struct ctl_table *table, int write,
- struct file *filp, void __user *buffer, size_t *lenp,
+ struct file *file, void __user *buffer, size_t *lenp,
loff_t *ppos)
{
int ret;
mutex_lock(&ftrace_sysctl_lock);
- ret = proc_dointvec(table, write, filp, buffer, lenp, ppos);
+ ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
if (ret || !write || (last_ftrace_enabled == ftrace_enabled))
goto out;
projects / mirror_ubuntu-bionic-kernel.git / commitdiff