#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/kthread.h>
#include <linux/uaccess.h>
+#include <linux/ftrace.h>
#include <linux/sysctl.h>
-#include <linux/hash.h>
#include <linux/ctype.h>
+#include <linux/hash.h>
#include <linux/list.h>
#include "trace.h"
static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
-/* mcount is defined per arch in assembly */
-EXPORT_SYMBOL(mcount);
-
void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
{
struct ftrace_ops *op = ftrace_list;
static DEFINE_SPINLOCK(ftrace_shutdown_lock);
static DEFINE_MUTEX(ftraced_lock);
-static DEFINE_MUTEX(ftrace_filter_lock);
+static DEFINE_MUTEX(ftrace_regex_lock);
struct ftrace_page {
struct ftrace_page *next;
- int index;
+ unsigned long index;
struct dyn_ftrace records[];
-} __attribute__((packed));
+};
#define ENTRIES_PER_PAGE \
((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace))
struct hlist_node *t;
int found = 0;
- hlist_for_each_entry(p, t, &ftrace_hash[key], node) {
+ hlist_for_each_entry_rcu(p, t, &ftrace_hash[key], node) {
if (p->ip == ip) {
found = 1;
break;
static inline void
ftrace_add_hash(struct dyn_ftrace *node, unsigned long key)
{
- hlist_add_head(&node->node, &ftrace_hash[key]);
+ hlist_add_head_rcu(&node->node, &ftrace_hash[key]);
}
static void ftrace_free_rec(struct dyn_ftrace *rec)
unsigned long key;
int resched;
int atomic;
+ int cpu;
if (!ftrace_enabled || ftrace_disabled)
return;
resched = need_resched();
preempt_disable_notrace();
- /* We simply need to protect against recursion */
- __get_cpu_var(ftrace_shutdown_disable_cpu)++;
- if (__get_cpu_var(ftrace_shutdown_disable_cpu) != 1)
+ /*
+ * We simply need to protect against recursion.
+ * Use the the raw version of smp_processor_id and not
+ * __get_cpu_var which can call debug hooks that can
+ * cause a recursive crash here.
+ */
+ cpu = raw_smp_processor_id();
+ per_cpu(ftrace_shutdown_disable_cpu, cpu)++;
+ if (per_cpu(ftrace_shutdown_disable_cpu, cpu) != 1)
goto out;
if (unlikely(ftrace_record_suspend))
out_unlock:
spin_unlock_irqrestore(&ftrace_shutdown_lock, flags);
out:
- __get_cpu_var(ftrace_shutdown_disable_cpu)--;
+ per_cpu(ftrace_shutdown_disable_cpu, cpu)--;
/* prevent recursion with scheduler */
if (resched)
__ftrace_replace_code(struct dyn_ftrace *rec,
unsigned char *old, unsigned char *new, int enable)
{
- unsigned long ip;
+ unsigned long ip, fl;
int failed;
ip = rec->ip;
if (ftrace_filtered && enable) {
- unsigned long fl;
/*
* If filtering is on:
*
* If this record is not set to be filtered
* and it is not enabled do nothing.
*
+ * If this record is set not to trace then
+ * 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))
+ (fl == 0) || (rec->flags & FTRACE_FL_NOTRACE))
return;
/*
}
} else {
- if (enable)
+ if (enable) {
+ /*
+ * If this record is set not to trace and is
+ * not enabled, do nothing.
+ */
+ fl = rec->flags & (FTRACE_FL_NOTRACE | FTRACE_FL_ENABLED);
+ if (fl == FTRACE_FL_NOTRACE)
+ return;
+
new = ftrace_call_replace(ip, FTRACE_ADDR);
- else
+ } else
old = ftrace_call_replace(ip, FTRACE_ADDR);
if (enable) {
{
unsigned long usecs;
- set_current_state(TASK_INTERRUPTIBLE);
-
while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+
/* check once a second */
schedule_timeout(HZ);
wake_up_interruptible(&ftraced_waiters);
ftrace_shutdown_replenish();
-
- set_current_state(TASK_INTERRUPTIBLE);
}
__set_current_state(TASK_RUNNING);
return 0;
enum {
FTRACE_ITER_FILTER = (1 << 0),
FTRACE_ITER_CONT = (1 << 1),
+ FTRACE_ITER_NOTRACE = (1 << 2),
};
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
rec = &iter->pg->records[iter->idx++];
if ((rec->flags & FTRACE_FL_FAILED) ||
((iter->flags & FTRACE_ITER_FILTER) &&
- !(rec->flags & FTRACE_FL_FILTER))) {
+ !(rec->flags & FTRACE_FL_FILTER)) ||
+ ((iter->flags & FTRACE_ITER_NOTRACE) &&
+ !(rec->flags & FTRACE_FL_NOTRACE))) {
rec = NULL;
goto retry;
}
return 0;
}
-static void ftrace_filter_reset(void)
+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();
- ftrace_filtered = 0;
+ 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 &= ~FTRACE_FL_FILTER;
+ rec->flags &= ~type;
}
pg = pg->next;
}
}
static int
-ftrace_filter_open(struct inode *inode, struct file *file)
+ftrace_regex_open(struct inode *inode, struct file *file, int enable)
{
struct ftrace_iterator *iter;
int ret = 0;
if (!iter)
return -ENOMEM;
- mutex_lock(&ftrace_filter_lock);
+ mutex_lock(&ftrace_regex_lock);
if ((file->f_mode & FMODE_WRITE) &&
!(file->f_flags & O_APPEND))
- ftrace_filter_reset();
+ ftrace_filter_reset(enable);
if (file->f_mode & FMODE_READ) {
iter->pg = ftrace_pages_start;
iter->pos = -1;
- iter->flags = FTRACE_ITER_FILTER;
+ iter->flags = enable ? FTRACE_ITER_FILTER :
+ FTRACE_ITER_NOTRACE;
ret = seq_open(file, &show_ftrace_seq_ops);
if (!ret) {
kfree(iter);
} else
file->private_data = iter;
- mutex_unlock(&ftrace_filter_lock);
+ 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_filter_read(struct file *file, char __user *ubuf,
+ftrace_regex_read(struct file *file, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
if (file->f_mode & FMODE_READ)
}
static loff_t
-ftrace_filter_lseek(struct file *file, loff_t offset, int origin)
+ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
{
loff_t ret;
};
static void
-ftrace_match(unsigned char *buff, int len)
+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++) {
/* keep kstop machine from running */
preempt_disable();
- ftrace_filtered = 1;
+ if (enable)
+ ftrace_filtered = 1;
pg = ftrace_pages_start;
while (pg) {
for (i = 0; i < pg->index; i++) {
break;
}
if (matched)
- rec->flags |= FTRACE_FL_FILTER;
+ rec->flags |= flag;
}
pg = pg->next;
}
}
static ssize_t
-ftrace_filter_write(struct file *file, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
+ftrace_regex_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos, int enable)
{
struct ftrace_iterator *iter;
char ch;
if (!cnt || cnt < 0)
return 0;
- mutex_lock(&ftrace_filter_lock);
+ mutex_lock(&ftrace_regex_lock);
if (file->f_mode & FMODE_READ) {
struct seq_file *m = file->private_data;
cnt--;
}
-
if (isspace(ch)) {
file->f_pos += read;
ret = read;
if (isspace(ch)) {
iter->filtered++;
iter->buffer[iter->buffer_idx] = 0;
- ftrace_match(iter->buffer, iter->buffer_idx);
+ ftrace_match(iter->buffer, iter->buffer_idx, enable);
iter->buffer_idx = 0;
} else
iter->flags |= FTRACE_ITER_CONT;
ret = read;
out:
- mutex_unlock(&ftrace_filter_lock);
+ 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.
*/
void ftrace_set_filter(unsigned char *buf, int len, int reset)
{
- if (unlikely(ftrace_disabled))
- return;
+ ftrace_set_regex(buf, len, reset, 1);
+}
- mutex_lock(&ftrace_filter_lock);
- if (reset)
- ftrace_filter_reset();
- if (buf)
- ftrace_match(buf, len);
- mutex_unlock(&ftrace_filter_lock);
+/**
+ * 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_filter_release(struct inode *inode, struct file *file)
+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_filter_lock);
+ mutex_lock(&ftrace_regex_lock);
if (file->f_mode & FMODE_READ) {
iter = m->private;
if (iter->buffer_idx) {
iter->filtered++;
iter->buffer[iter->buffer_idx] = 0;
- ftrace_match(iter->buffer, iter->buffer_idx);
+ ftrace_match(iter->buffer, iter->buffer_idx, enable);
}
mutex_lock(&ftrace_sysctl_lock);
mutex_unlock(&ftrace_sysctl_lock);
kfree(iter);
- mutex_unlock(&ftrace_filter_lock);
+ 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 struct file_operations ftrace_avail_fops = {
.open = ftrace_avail_open,
.read = seq_read,
static struct file_operations ftrace_filter_fops = {
.open = ftrace_filter_open,
- .read = ftrace_filter_read,
+ .read = ftrace_regex_read,
.write = ftrace_filter_write,
- .llseek = ftrace_filter_lseek,
+ .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,
+};
+
/**
* ftrace_force_update - force an update to all recording ftrace functions
*
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");
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff