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Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c162
1 files changed, 90 insertions, 72 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index cd7f76d1eb86..1fd4b9479210 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -237,14 +237,13 @@ static int control_ops_alloc(struct ftrace_ops *ops)
return 0;
}
-static void control_ops_free(struct ftrace_ops *ops)
-{
- free_percpu(ops->disabled);
-}
-
static void update_global_ops(void)
{
- ftrace_func_t func;
+ ftrace_func_t func = ftrace_global_list_func;
+ void *private = NULL;
+
+ /* The list has its own recursion protection. */
+ global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
/*
* If there's only one function registered, then call that
@@ -254,23 +253,17 @@ static void update_global_ops(void)
if (ftrace_global_list == &ftrace_list_end ||
ftrace_global_list->next == &ftrace_list_end) {
func = ftrace_global_list->func;
+ private = ftrace_global_list->private;
/*
* As we are calling the function directly.
* If it does not have recursion protection,
* the function_trace_op needs to be updated
* accordingly.
*/
- if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE)
- global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
- else
+ if (!(ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE))
global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE;
- } else {
- func = ftrace_global_list_func;
- /* The list has its own recursion protection. */
- global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
}
-
/* If we filter on pids, update to use the pid function */
if (!list_empty(&ftrace_pids)) {
set_ftrace_pid_function(func);
@@ -278,6 +271,7 @@ static void update_global_ops(void)
}
global_ops.func = func;
+ global_ops.private = private;
}
static void ftrace_sync(struct work_struct *work)
@@ -437,6 +431,9 @@ static int remove_ftrace_list_ops(struct ftrace_ops **list,
static int __register_ftrace_function(struct ftrace_ops *ops)
{
+ if (ops->flags & FTRACE_OPS_FL_DELETED)
+ return -EINVAL;
+
if (FTRACE_WARN_ON(ops == &global_ops))
return -EINVAL;
@@ -1172,8 +1169,6 @@ struct ftrace_page {
int size;
};
-static struct ftrace_page *ftrace_new_pgs;
-
#define ENTRY_SIZE sizeof(struct dyn_ftrace)
#define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE)
@@ -1560,7 +1555,7 @@ unsigned long ftrace_location(unsigned long ip)
* the function tracer. It checks the ftrace internal tables to
* determine if the address belongs or not.
*/
-int ftrace_text_reserved(void *start, void *end)
+int ftrace_text_reserved(const void *start, const void *end)
{
unsigned long ret;
@@ -1994,6 +1989,7 @@ int __weak ftrace_arch_code_modify_post_process(void)
void ftrace_modify_all_code(int command)
{
int update = command & FTRACE_UPDATE_TRACE_FUNC;
+ int err = 0;
/*
* If the ftrace_caller calls a ftrace_ops func directly,
@@ -2005,8 +2001,11 @@ void ftrace_modify_all_code(int command)
* to make sure the ops are having the right functions
* traced.
*/
- if (update)
- ftrace_update_ftrace_func(ftrace_ops_list_func);
+ if (update) {
+ err = ftrace_update_ftrace_func(ftrace_ops_list_func);
+ if (FTRACE_WARN_ON(err))
+ return;
+ }
if (command & FTRACE_UPDATE_CALLS)
ftrace_replace_code(1);
@@ -2019,13 +2018,16 @@ void ftrace_modify_all_code(int command)
/* If irqs are disabled, we are in stop machine */
if (!irqs_disabled())
smp_call_function(ftrace_sync_ipi, NULL, 1);
- ftrace_update_ftrace_func(ftrace_trace_function);
+ err = ftrace_update_ftrace_func(ftrace_trace_function);
+ if (FTRACE_WARN_ON(err))
+ return;
}
if (command & FTRACE_START_FUNC_RET)
- ftrace_enable_ftrace_graph_caller();
+ err = ftrace_enable_ftrace_graph_caller();
else if (command & FTRACE_STOP_FUNC_RET)
- ftrace_disable_ftrace_graph_caller();
+ err = ftrace_disable_ftrace_graph_caller();
+ FTRACE_WARN_ON(err);
}
static int __ftrace_modify_code(void *data)
@@ -2093,6 +2095,11 @@ static ftrace_func_t saved_ftrace_func;
static int ftrace_start_up;
static int global_start_up;
+static void control_ops_free(struct ftrace_ops *ops)
+{
+ free_percpu(ops->disabled);
+}
+
static void ftrace_startup_enable(int command)
{
if (saved_ftrace_func != ftrace_trace_function) {
@@ -2244,7 +2251,6 @@ static void ftrace_shutdown_sysctl(void)
}
static cycle_t ftrace_update_time;
-static unsigned long ftrace_update_cnt;
unsigned long ftrace_update_tot_cnt;
static inline int ops_traces_mod(struct ftrace_ops *ops)
@@ -2300,11 +2306,12 @@ static int referenced_filters(struct dyn_ftrace *rec)
return cnt;
}
-static int ftrace_update_code(struct module *mod)
+static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
{
struct ftrace_page *pg;
struct dyn_ftrace *p;
cycle_t start, stop;
+ unsigned long update_cnt = 0;
unsigned long ref = 0;
bool test = false;
int i;
@@ -2330,9 +2337,8 @@ static int ftrace_update_code(struct module *mod)
}
start = ftrace_now(raw_smp_processor_id());
- ftrace_update_cnt = 0;
- for (pg = ftrace_new_pgs; pg; pg = pg->next) {
+ for (pg = new_pgs; pg; pg = pg->next) {
for (i = 0; i < pg->index; i++) {
int cnt = ref;
@@ -2353,7 +2359,7 @@ static int ftrace_update_code(struct module *mod)
if (!ftrace_code_disable(mod, p))
break;
- ftrace_update_cnt++;
+ update_cnt++;
/*
* If the tracing is enabled, go ahead and enable the record.
@@ -2372,11 +2378,9 @@ static int ftrace_update_code(struct module *mod)
}
}
- ftrace_new_pgs = NULL;
-
stop = ftrace_now(raw_smp_processor_id());
ftrace_update_time = stop - start;
- ftrace_update_tot_cnt += ftrace_update_cnt;
+ ftrace_update_tot_cnt += update_cnt;
return 0;
}
@@ -2468,22 +2472,6 @@ ftrace_allocate_pages(unsigned long num_to_init)
return NULL;
}
-static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
-{
- int cnt;
-
- if (!num_to_init) {
- pr_info("ftrace: No functions to be traced?\n");
- return -1;
- }
-
- cnt = num_to_init / ENTRIES_PER_PAGE;
- pr_info("ftrace: allocating %ld entries in %d pages\n",
- num_to_init, cnt + 1);
-
- return 0;
-}
-
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
struct ftrace_iterator {
@@ -2871,7 +2859,9 @@ ftrace_regex_open(struct ftrace_ops *ops, int flag,
static int
ftrace_filter_open(struct inode *inode, struct file *file)
{
- return ftrace_regex_open(&global_ops,
+ struct ftrace_ops *ops = inode->i_private;
+
+ return ftrace_regex_open(ops,
FTRACE_ITER_FILTER | FTRACE_ITER_DO_HASH,
inode, file);
}
@@ -2879,7 +2869,9 @@ ftrace_filter_open(struct inode *inode, struct file *file)
static int
ftrace_notrace_open(struct inode *inode, struct file *file)
{
- return ftrace_regex_open(&global_ops, FTRACE_ITER_NOTRACE,
+ struct ftrace_ops *ops = inode->i_private;
+
+ return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE,
inode, file);
}
@@ -4109,6 +4101,36 @@ static const struct file_operations ftrace_graph_notrace_fops = {
};
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+void ftrace_create_filter_files(struct ftrace_ops *ops,
+ struct dentry *parent)
+{
+
+ trace_create_file("set_ftrace_filter", 0644, parent,
+ ops, &ftrace_filter_fops);
+
+ trace_create_file("set_ftrace_notrace", 0644, parent,
+ ops, &ftrace_notrace_fops);
+}
+
+/*
+ * The name "destroy_filter_files" is really a misnomer. Although
+ * in the future, it may actualy delete the files, but this is
+ * really intended to make sure the ops passed in are disabled
+ * and that when this function returns, the caller is free to
+ * free the ops.
+ *
+ * The "destroy" name is only to match the "create" name that this
+ * should be paired with.
+ */
+void ftrace_destroy_filter_files(struct ftrace_ops *ops)
+{
+ mutex_lock(&ftrace_lock);
+ if (ops->flags & FTRACE_OPS_FL_ENABLED)
+ ftrace_shutdown(ops, 0);
+ ops->flags |= FTRACE_OPS_FL_DELETED;
+ mutex_unlock(&ftrace_lock);
+}
+
static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
{
@@ -4118,11 +4140,7 @@ static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
trace_create_file("enabled_functions", 0444,
d_tracer, NULL, &ftrace_enabled_fops);
- trace_create_file("set_ftrace_filter", 0644, d_tracer,
- NULL, &ftrace_filter_fops);
-
- trace_create_file("set_ftrace_notrace", 0644, d_tracer,
- NULL, &ftrace_notrace_fops);
+ ftrace_create_filter_files(&global_ops, d_tracer);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
trace_create_file("set_graph_function", 0444, d_tracer,
@@ -4238,9 +4256,6 @@ static int ftrace_process_locs(struct module *mod,
/* Assign the last page to ftrace_pages */
ftrace_pages = pg;
- /* These new locations need to be initialized */
- ftrace_new_pgs = start_pg;
-
/*
* We only need to disable interrupts on start up
* because we are modifying code that an interrupt
@@ -4251,7 +4266,7 @@ static int ftrace_process_locs(struct module *mod,
*/
if (!mod)
local_irq_save(flags);
- ftrace_update_code(mod);
+ ftrace_update_code(mod, start_pg);
if (!mod)
local_irq_restore(flags);
ret = 0;
@@ -4360,30 +4375,27 @@ struct notifier_block ftrace_module_exit_nb = {
.priority = INT_MIN, /* Run after anything that can remove kprobes */
};
-extern unsigned long __start_mcount_loc[];
-extern unsigned long __stop_mcount_loc[];
-
void __init ftrace_init(void)
{
- unsigned long count, addr, flags;
+ extern unsigned long __start_mcount_loc[];
+ extern unsigned long __stop_mcount_loc[];
+ unsigned long count, flags;
int ret;
- /* Keep the ftrace pointer to the stub */
- addr = (unsigned long)ftrace_stub;
-
local_irq_save(flags);
- ftrace_dyn_arch_init(&addr);
+ ret = ftrace_dyn_arch_init();
local_irq_restore(flags);
-
- /* ftrace_dyn_arch_init places the return code in addr */
- if (addr)
+ if (ret)
goto failed;
count = __stop_mcount_loc - __start_mcount_loc;
-
- ret = ftrace_dyn_table_alloc(count);
- if (ret)
+ if (!count) {
+ pr_info("ftrace: No functions to be traced?\n");
goto failed;
+ }
+
+ pr_info("ftrace: allocating %ld entries in %ld pages\n",
+ count, count / ENTRIES_PER_PAGE + 1);
last_ftrace_enabled = ftrace_enabled = 1;
@@ -4431,7 +4443,13 @@ static inline void ftrace_startup_enable(int command) { }
(ops)->flags |= FTRACE_OPS_FL_ENABLED; \
___ret; \
})
-# define ftrace_shutdown(ops, command) __unregister_ftrace_function(ops)
+# define ftrace_shutdown(ops, command) \
+ ({ \
+ int ___ret = __unregister_ftrace_function(ops); \
+ if (!___ret) \
+ (ops)->flags &= ~FTRACE_OPS_FL_ENABLED; \
+ ___ret; \
+ })
# define ftrace_startup_sysctl() do { } while (0)
# define ftrace_shutdown_sysctl() do { } while (0)