#include <linux/sysctl.h>
#include <linux/ctype.h>
#include <linux/list.h>
+#include <linux/hash.h>
#include <asm/ftrace.h>
ftrace_kill(); \
} while (0)
+/* hash bits for specific function selection */
+#define FTRACE_HASH_BITS 7
+#define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS)
+
/* ftrace_enabled is a method to turn ftrace on or off */
int ftrace_enabled __read_mostly;
static int last_ftrace_enabled;
-/* set when tracing only a pid */
-struct pid *ftrace_pid_trace;
-static struct pid * const ftrace_swapper_pid = &init_struct_pid;
-
/* Quick disabling of function tracer. */
int function_trace_stop;
{
ftrace_func_t func;
- mutex_lock(&ftrace_lock);
-
if (ftrace_trace_function == ftrace_stub)
- goto out;
+ return;
func = ftrace_trace_function;
#else
__ftrace_trace_function = func;
#endif
-
- out:
- mutex_unlock(&ftrace_lock);
}
+/* set when tracing only a pid */
+struct pid *ftrace_pid_trace;
+static struct pid * const ftrace_swapper_pid = &init_struct_pid;
+
#ifdef CONFIG_DYNAMIC_FTRACE
+
#ifndef CONFIG_FTRACE_MCOUNT_RECORD
# error Dynamic ftrace depends on MCOUNT_RECORD
#endif
+static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly;
+
+struct ftrace_func_probe {
+ struct hlist_node node;
+ struct ftrace_probe_ops *ops;
+ unsigned long flags;
+ unsigned long ip;
+ void *data;
+ struct rcu_head rcu;
+};
+
+
enum {
FTRACE_ENABLE_CALLS = (1 << 0),
FTRACE_DISABLE_CALLS = (1 << 1),
static int
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
- unsigned long ip, fl;
unsigned long ftrace_addr;
+ unsigned long ip, fl;
ftrace_addr = (unsigned long)FTRACE_ADDR;
static void ftrace_replace_code(int enable)
{
- int failed;
struct dyn_ftrace *rec;
struct ftrace_page *pg;
+ int failed;
do_for_each_ftrace_rec(pg, rec) {
/*
if ((system_state == SYSTEM_BOOTING) ||
!core_kernel_text(rec->ip)) {
ftrace_free_rec(rec);
- } else
+ } else {
ftrace_bug(failed, rec->ip);
+ /* Stop processing */
+ return;
+ }
}
} while_for_each_ftrace_rec();
}
return 1;
}
+/*
+ * archs can override this function if they must do something
+ * before the modifying code is performed.
+ */
+int __weak ftrace_arch_code_modify_prepare(void)
+{
+ return 0;
+}
+
+/*
+ * archs can override this function if they must do something
+ * after the modifying code is performed.
+ */
+int __weak ftrace_arch_code_modify_post_process(void)
+{
+ return 0;
+}
+
static int __ftrace_modify_code(void *data)
{
int *command = data;
static void ftrace_run_update_code(int command)
{
+ int ret;
+
+ ret = ftrace_arch_code_modify_prepare();
+ FTRACE_WARN_ON(ret);
+ if (ret)
+ return;
+
stop_machine(__ftrace_modify_code, &command, NULL);
+
+ ret = ftrace_arch_code_modify_post_process();
+ FTRACE_WARN_ON(ret);
}
static ftrace_func_t saved_ftrace_func;
FTRACE_ITER_NOTRACE = (1 << 2),
FTRACE_ITER_FAILURES = (1 << 3),
FTRACE_ITER_PRINTALL = (1 << 4),
+ FTRACE_ITER_HASH = (1 << 5),
};
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
struct ftrace_iterator {
struct ftrace_page *pg;
+ int hidx;
int idx;
unsigned flags;
unsigned char buffer[FTRACE_BUFF_MAX+1];
unsigned filtered;
};
+static void *
+t_hash_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ struct hlist_node *hnd = v;
+ struct hlist_head *hhd;
+
+ WARN_ON(!(iter->flags & FTRACE_ITER_HASH));
+
+ (*pos)++;
+
+ retry:
+ if (iter->hidx >= FTRACE_FUNC_HASHSIZE)
+ return NULL;
+
+ hhd = &ftrace_func_hash[iter->hidx];
+
+ if (hlist_empty(hhd)) {
+ iter->hidx++;
+ hnd = NULL;
+ goto retry;
+ }
+
+ if (!hnd)
+ hnd = hhd->first;
+ else {
+ hnd = hnd->next;
+ if (!hnd) {
+ iter->hidx++;
+ goto retry;
+ }
+ }
+
+ return hnd;
+}
+
+static void *t_hash_start(struct seq_file *m, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ void *p = NULL;
+
+ iter->flags |= FTRACE_ITER_HASH;
+
+ return t_hash_next(m, p, pos);
+}
+
+static int t_hash_show(struct seq_file *m, void *v)
+{
+ struct ftrace_func_probe *rec;
+ struct hlist_node *hnd = v;
+ char str[KSYM_SYMBOL_LEN];
+
+ rec = hlist_entry(hnd, struct ftrace_func_probe, node);
+
+ if (rec->ops->print)
+ return rec->ops->print(m, rec->ip, rec->ops, rec->data);
+
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ seq_printf(m, "%s:", str);
+
+ kallsyms_lookup((unsigned long)rec->ops->func, NULL, NULL, NULL, str);
+ seq_printf(m, "%s", str);
+
+ if (rec->data)
+ seq_printf(m, ":%p", rec->data);
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
struct ftrace_iterator *iter = m->private;
struct dyn_ftrace *rec = NULL;
+ if (iter->flags & FTRACE_ITER_HASH)
+ return t_hash_next(m, v, pos);
+
(*pos)++;
if (iter->flags & FTRACE_ITER_PRINTALL)
return NULL;
- mutex_lock(&ftrace_lock);
retry:
if (iter->idx >= iter->pg->index) {
if (iter->pg->next) {
goto retry;
}
}
- mutex_unlock(&ftrace_lock);
return rec;
}
struct ftrace_iterator *iter = m->private;
void *p = NULL;
+ mutex_lock(&ftrace_lock);
/*
* For set_ftrace_filter reading, if we have the filter
* off, we can short cut and just print out that all
*/
if (iter->flags & FTRACE_ITER_FILTER && !ftrace_filtered) {
if (*pos > 0)
- return NULL;
+ return t_hash_start(m, pos);
iter->flags |= FTRACE_ITER_PRINTALL;
(*pos)++;
return iter;
}
+ if (iter->flags & FTRACE_ITER_HASH)
+ return t_hash_start(m, pos);
+
if (*pos > 0) {
if (iter->idx < 0)
return p;
p = t_next(m, p, pos);
+ if (!p)
+ return t_hash_start(m, pos);
+
return p;
}
static void t_stop(struct seq_file *m, void *p)
{
+ mutex_unlock(&ftrace_lock);
}
static int t_show(struct seq_file *m, void *v)
struct dyn_ftrace *rec = v;
char str[KSYM_SYMBOL_LEN];
+ if (iter->flags & FTRACE_ITER_HASH)
+ return t_hash_show(m, v);
+
if (iter->flags & FTRACE_ITER_PRINTALL) {
seq_printf(m, "#### all functions enabled ####\n");
return 0;
static void ftrace_match_records(char *buff, int len, int enable)
{
- char *search;
+ unsigned int search_len;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
+ unsigned long flag;
+ char *search;
int type;
- unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- unsigned search_len;
int not;
+ flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
type = ftrace_setup_glob(buff, len, &search, ¬);
search_len = strlen(search);
static void ftrace_match_module_records(char *buff, char *mod, int enable)
{
- char *search = buff;
+ unsigned search_len = 0;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
int type = MATCH_FULL;
- unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
- unsigned search_len = 0;
+ char *search = buff;
+ unsigned long flag;
int not = 0;
+ flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+
/* blank or '*' mean the same */
if (strcmp(buff, "*") == 0)
buff[0] = 0;
}
device_initcall(ftrace_mod_cmd_init);
+static void
+function_trace_probe_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct ftrace_func_probe *entry;
+ struct hlist_head *hhd;
+ struct hlist_node *n;
+ unsigned long key;
+ int resched;
+
+ key = hash_long(ip, FTRACE_HASH_BITS);
+
+ hhd = &ftrace_func_hash[key];
+
+ if (hlist_empty(hhd))
+ return;
+
+ /*
+ * Disable preemption for these calls to prevent a RCU grace
+ * period. This syncs the hash iteration and freeing of items
+ * on the hash. rcu_read_lock is too dangerous here.
+ */
+ resched = ftrace_preempt_disable();
+ hlist_for_each_entry_rcu(entry, n, hhd, node) {
+ if (entry->ip == ip)
+ entry->ops->func(ip, parent_ip, &entry->data);
+ }
+ ftrace_preempt_enable(resched);
+}
+
+static struct ftrace_ops trace_probe_ops __read_mostly =
+{
+ .func = function_trace_probe_call,
+};
+
+static int ftrace_probe_registered;
+
+static void __enable_ftrace_function_probe(void)
+{
+ int i;
+
+ if (ftrace_probe_registered)
+ return;
+
+ for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
+ struct hlist_head *hhd = &ftrace_func_hash[i];
+ if (hhd->first)
+ break;
+ }
+ /* Nothing registered? */
+ if (i == FTRACE_FUNC_HASHSIZE)
+ return;
+
+ __register_ftrace_function(&trace_probe_ops);
+ ftrace_startup(0);
+ ftrace_probe_registered = 1;
+}
+
+static void __disable_ftrace_function_probe(void)
+{
+ int i;
+
+ if (!ftrace_probe_registered)
+ return;
+
+ for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
+ struct hlist_head *hhd = &ftrace_func_hash[i];
+ if (hhd->first)
+ return;
+ }
+
+ /* no more funcs left */
+ __unregister_ftrace_function(&trace_probe_ops);
+ ftrace_shutdown(0);
+ ftrace_probe_registered = 0;
+}
+
+
+static void ftrace_free_entry_rcu(struct rcu_head *rhp)
+{
+ struct ftrace_func_probe *entry =
+ container_of(rhp, struct ftrace_func_probe, rcu);
+
+ if (entry->ops->free)
+ entry->ops->free(&entry->data);
+ kfree(entry);
+}
+
+
+int
+register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
+ void *data)
+{
+ struct ftrace_func_probe *entry;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int type, len, not;
+ unsigned long key;
+ int count = 0;
+ char *search;
+
+ type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ len = strlen(search);
+
+ /* we do not support '!' for function probes */
+ if (WARN_ON(not))
+ return -EINVAL;
+
+ mutex_lock(&ftrace_lock);
+ do_for_each_ftrace_rec(pg, rec) {
+
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+
+ if (!ftrace_match_record(rec, search, len, type))
+ continue;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ /* If we did not process any, then return error */
+ if (!count)
+ count = -ENOMEM;
+ goto out_unlock;
+ }
+
+ count++;
+
+ entry->data = data;
+
+ /*
+ * The caller might want to do something special
+ * for each function we find. We call the callback
+ * to give the caller an opportunity to do so.
+ */
+ if (ops->callback) {
+ if (ops->callback(rec->ip, &entry->data) < 0) {
+ /* caller does not like this func */
+ kfree(entry);
+ continue;
+ }
+ }
+
+ entry->ops = ops;
+ entry->ip = rec->ip;
+
+ key = hash_long(entry->ip, FTRACE_HASH_BITS);
+ hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]);
+
+ } while_for_each_ftrace_rec();
+ __enable_ftrace_function_probe();
+
+ out_unlock:
+ mutex_unlock(&ftrace_lock);
+
+ return count;
+}
+
+enum {
+ PROBE_TEST_FUNC = 1,
+ PROBE_TEST_DATA = 2
+};
+
+static void
+__unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
+ void *data, int flags)
+{
+ struct ftrace_func_probe *entry;
+ struct hlist_node *n, *tmp;
+ char str[KSYM_SYMBOL_LEN];
+ int type = MATCH_FULL;
+ int i, len = 0;
+ char *search;
+
+ if (glob && (strcmp(glob, "*") || !strlen(glob)))
+ glob = NULL;
+ else {
+ int not;
+
+ type = ftrace_setup_glob(glob, strlen(glob), &search, ¬);
+ len = strlen(search);
+
+ /* we do not support '!' for function probes */
+ if (WARN_ON(not))
+ return;
+ }
+
+ mutex_lock(&ftrace_lock);
+ for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
+ struct hlist_head *hhd = &ftrace_func_hash[i];
+
+ hlist_for_each_entry_safe(entry, n, tmp, hhd, node) {
+
+ /* break up if statements for readability */
+ if ((flags & PROBE_TEST_FUNC) && entry->ops != ops)
+ continue;
+
+ if ((flags & PROBE_TEST_DATA) && entry->data != data)
+ continue;
+
+ /* do this last, since it is the most expensive */
+ if (glob) {
+ kallsyms_lookup(entry->ip, NULL, NULL,
+ NULL, str);
+ if (!ftrace_match(str, glob, len, type))
+ continue;
+ }
+
+ hlist_del(&entry->node);
+ call_rcu(&entry->rcu, ftrace_free_entry_rcu);
+ }
+ }
+ __disable_ftrace_function_probe();
+ mutex_unlock(&ftrace_lock);
+}
+
+void
+unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
+ void *data)
+{
+ __unregister_ftrace_function_probe(glob, ops, data,
+ PROBE_TEST_FUNC | PROBE_TEST_DATA);
+}
+
+void
+unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
+{
+ __unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC);
+}
+
+void unregister_ftrace_function_probe_all(char *glob)
+{
+ __unregister_ftrace_function_probe(glob, NULL, NULL, 0);
+}
+
static LIST_HEAD(ftrace_commands);
static DEFINE_MUTEX(ftrace_cmd_mutex);
static int ftrace_process_regex(char *buff, int len, int enable)
{
- struct ftrace_func_command *p;
char *func, *command, *next = buff;
+ struct ftrace_func_command *p;
int ret = -EINVAL;
func = strsep(&next, ":");
return ftrace_regex_release(inode, file, 0);
}
-static struct file_operations ftrace_avail_fops = {
+static const 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 = {
+static const 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 = {
+static const struct file_operations ftrace_filter_fops = {
.open = ftrace_filter_open,
.read = ftrace_regex_read,
.write = ftrace_filter_write,
.release = ftrace_filter_release,
};
-static struct file_operations ftrace_notrace_fops = {
+static const struct file_operations ftrace_notrace_fops = {
.open = ftrace_notrace_open,
.read = ftrace_regex_read,
.write = ftrace_notrace_write,
mutex_lock(&graph_lock);
+ /* Nothing, tell g_show to print all functions are enabled */
+ if (!ftrace_graph_count && !*pos)
+ return (void *)1;
+
p = g_next(m, p, pos);
return p;
if (!ptr)
return 0;
+ if (ptr == (unsigned long *)1) {
+ seq_printf(m, "#### all functions enabled ####\n");
+ return 0;
+ }
+
kallsyms_lookup(*ptr, NULL, NULL, NULL, str);
seq_printf(m, "%s\n", str);
}
static int
-ftrace_set_func(unsigned long *array, int idx, char *buffer)
+ftrace_set_func(unsigned long *array, int *idx, char *buffer)
{
- char str[KSYM_SYMBOL_LEN];
struct dyn_ftrace *rec;
struct ftrace_page *pg;
+ int search_len;
int found = 0;
- int j;
+ int type, not;
+ char *search;
+ bool exists;
+ int i;
if (ftrace_disabled)
return -ENODEV;
+ /* decode regex */
+ type = ftrace_setup_glob(buffer, strlen(buffer), &search, ¬);
+ if (not)
+ return -EINVAL;
+
+ search_len = strlen(search);
+
mutex_lock(&ftrace_lock);
do_for_each_ftrace_rec(pg, rec) {
+ if (*idx >= FTRACE_GRAPH_MAX_FUNCS)
+ break;
+
if (rec->flags & (FTRACE_FL_FAILED | FTRACE_FL_FREE))
continue;
- kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
- if (strcmp(str, buffer) == 0) {
- /* Return 1 if we add it to the array */
- found = 1;
- for (j = 0; j < idx; j++)
- if (array[j] == rec->ip) {
- found = 0;
+ if (ftrace_match_record(rec, search, search_len, type)) {
+ /* ensure it is not already in the array */
+ exists = false;
+ for (i = 0; i < *idx; i++)
+ if (array[i] == rec->ip) {
+ exists = true;
break;
}
- if (found)
- array[idx] = rec->ip;
- goto out;
+ if (!exists) {
+ array[(*idx)++] = rec->ip;
+ found = 1;
+ }
}
} while_for_each_ftrace_rec();
- out:
+
mutex_unlock(&ftrace_lock);
return found ? 0 : -EINVAL;
}
buffer[index] = 0;
- /* we allow only one at a time */
- ret = ftrace_set_func(array, ftrace_graph_count, buffer);
+ /* we allow only one expression at a time */
+ ret = ftrace_set_func(array, &ftrace_graph_count, buffer);
if (ret)
goto out;
- ftrace_graph_count++;
-
file->f_pos += read;
ret = read;
return cnt;
}
-static struct file_operations ftrace_pid_fops = {
+static const struct file_operations ftrace_pid_fops = {
.read = ftrace_pid_read,
.write = ftrace_pid_write,
};
"'set_ftrace_pid' entry\n");
return 0;
}
-
fs_initcall(ftrace_init_debugfs);
/**
static int start_graph_tracing(void)
{
struct ftrace_ret_stack **ret_stack_list;
- int ret;
+ int ret, cpu;
ret_stack_list = kmalloc(FTRACE_RETSTACK_ALLOC_SIZE *
sizeof(struct ftrace_ret_stack *),
if (!ret_stack_list)
return -ENOMEM;
+ /* The cpu_boot init_task->ret_stack will never be freed */
+ for_each_online_cpu(cpu)
+ ftrace_graph_init_task(idle_task(cpu));
+
do {
ret = alloc_retstack_tasklist(ret_stack_list);
} while (ret == -EAGAIN);
projects / linux-2.6-omap-h63xx.git / blobdiff