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-rw-r--r--kernel/trace/ftrace.c294
1 files changed, 120 insertions, 174 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 1fd4b9479210..5b372e3ed675 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -62,7 +62,7 @@
#define FTRACE_HASH_DEFAULT_BITS 10
#define FTRACE_HASH_MAX_BITS 12
-#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL)
+#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_CONTROL)
#ifdef CONFIG_DYNAMIC_FTRACE
#define INIT_REGEX_LOCK(opsname) \
@@ -103,7 +103,6 @@ static int ftrace_disabled __read_mostly;
static DEFINE_MUTEX(ftrace_lock);
-static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
@@ -171,23 +170,6 @@ int ftrace_nr_registered_ops(void)
return cnt;
}
-static void
-ftrace_global_list_func(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *regs)
-{
- int bit;
-
- bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX);
- if (bit < 0)
- return;
-
- do_for_each_ftrace_op(op, ftrace_global_list) {
- op->func(ip, parent_ip, op, regs);
- } while_for_each_ftrace_op(op);
-
- trace_clear_recursion(bit);
-}
-
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
{
@@ -237,43 +219,6 @@ static int control_ops_alloc(struct ftrace_ops *ops)
return 0;
}
-static void update_global_ops(void)
-{
- 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
- * function directly. Otherwise, we need to iterate over the
- * registered callers.
- */
- 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;
- }
-
- /* If we filter on pids, update to use the pid function */
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
-
- global_ops.func = func;
- global_ops.private = private;
-}
-
static void ftrace_sync(struct work_struct *work)
{
/*
@@ -301,8 +246,6 @@ static void update_ftrace_function(void)
{
ftrace_func_t func;
- update_global_ops();
-
/*
* If we are at the end of the list and this ops is
* recursion safe and not dynamic and the arch supports passing ops,
@@ -314,10 +257,7 @@ static void update_ftrace_function(void)
(ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) &&
!FTRACE_FORCE_LIST_FUNC)) {
/* Set the ftrace_ops that the arch callback uses */
- if (ftrace_ops_list == &global_ops)
- set_function_trace_op = ftrace_global_list;
- else
- set_function_trace_op = ftrace_ops_list;
+ set_function_trace_op = ftrace_ops_list;
func = ftrace_ops_list->func;
} else {
/* Just use the default ftrace_ops */
@@ -373,6 +313,11 @@ static void update_ftrace_function(void)
ftrace_trace_function = func;
}
+int using_ftrace_ops_list_func(void)
+{
+ return ftrace_trace_function == ftrace_ops_list_func;
+}
+
static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops)
{
ops->next = *list;
@@ -434,16 +379,9 @@ 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;
-
if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
return -EBUSY;
- /* We don't support both control and global flags set. */
- if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
- return -EINVAL;
-
#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
/*
* If the ftrace_ops specifies SAVE_REGS, then it only can be used
@@ -461,10 +399,7 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if (!core_kernel_data((unsigned long)ops))
ops->flags |= FTRACE_OPS_FL_DYNAMIC;
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops);
- ops->flags |= FTRACE_OPS_FL_ENABLED;
- } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+ if (ops->flags & FTRACE_OPS_FL_CONTROL) {
if (control_ops_alloc(ops))
return -ENOMEM;
add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops);
@@ -484,15 +419,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED)))
return -EBUSY;
- if (FTRACE_WARN_ON(ops == &global_ops))
- return -EINVAL;
-
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ret = remove_ftrace_list_ops(&ftrace_global_list,
- &global_ops, ops);
- if (!ret)
- ops->flags &= ~FTRACE_OPS_FL_ENABLED;
- } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+ if (ops->flags & FTRACE_OPS_FL_CONTROL) {
ret = remove_ftrace_list_ops(&ftrace_control_list,
&control_ops, ops);
} else
@@ -895,7 +822,7 @@ function_profile_call(unsigned long ip, unsigned long parent_ip,
local_irq_save(flags);
- stat = &__get_cpu_var(ftrace_profile_stats);
+ stat = this_cpu_ptr(&ftrace_profile_stats);
if (!stat->hash || !ftrace_profile_enabled)
goto out;
@@ -926,7 +853,7 @@ static void profile_graph_return(struct ftrace_graph_ret *trace)
unsigned long flags;
local_irq_save(flags);
- stat = &__get_cpu_var(ftrace_profile_stats);
+ stat = this_cpu_ptr(&ftrace_profile_stats);
if (!stat->hash || !ftrace_profile_enabled)
goto out;
@@ -1178,7 +1105,7 @@ struct ftrace_page {
static struct ftrace_page *ftrace_pages_start;
static struct ftrace_page *ftrace_pages;
-static bool ftrace_hash_empty(struct ftrace_hash *hash)
+static bool __always_inline ftrace_hash_empty(struct ftrace_hash *hash)
{
return !hash || !hash->count;
}
@@ -1625,7 +1552,14 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip);
/*
+ * If filter_hash is set, we want to match all functions
+ * that are in the hash but not in the other hash.
*
+ * If filter_hash is not set, then we are decrementing.
+ * That means we match anything that is in the hash
+ * and also in the other_hash. That is, we need to turn
+ * off functions in the other hash because they are disabled
+ * by this hash.
*/
if (filter_hash && in_hash && !in_other_hash)
match = 1;
@@ -1767,19 +1701,15 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
/*
* If this record is being updated from a nop, then
* return UPDATE_MAKE_CALL.
- * Otherwise, if the EN flag is set, then return
- * UPDATE_MODIFY_CALL_REGS to tell the caller to convert
- * from the non-save regs, to a save regs function.
* Otherwise,
* return UPDATE_MODIFY_CALL to tell the caller to convert
- * from the save regs, to a non-save regs function.
+ * from the save regs, to a non-save regs function or
+ * vice versa.
*/
if (flag & FTRACE_FL_ENABLED)
return FTRACE_UPDATE_MAKE_CALL;
- else if (rec->flags & FTRACE_FL_REGS_EN)
- return FTRACE_UPDATE_MODIFY_CALL_REGS;
- else
- return FTRACE_UPDATE_MODIFY_CALL;
+
+ return FTRACE_UPDATE_MODIFY_CALL;
}
if (update) {
@@ -1821,6 +1751,42 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable)
return ftrace_check_record(rec, enable, 0);
}
+/**
+ * ftrace_get_addr_new - Get the call address to set to
+ * @rec: The ftrace record descriptor
+ *
+ * If the record has the FTRACE_FL_REGS set, that means that it
+ * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS
+ * is not not set, then it wants to convert to the normal callback.
+ *
+ * Returns the address of the trampoline to set to
+ */
+unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
+{
+ if (rec->flags & FTRACE_FL_REGS)
+ return (unsigned long)FTRACE_REGS_ADDR;
+ else
+ return (unsigned long)FTRACE_ADDR;
+}
+
+/**
+ * ftrace_get_addr_curr - Get the call address that is already there
+ * @rec: The ftrace record descriptor
+ *
+ * The FTRACE_FL_REGS_EN is set when the record already points to
+ * a function that saves all the regs. Basically the '_EN' version
+ * represents the current state of the function.
+ *
+ * Returns the address of the trampoline that is currently being called
+ */
+unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)
+{
+ if (rec->flags & FTRACE_FL_REGS_EN)
+ return (unsigned long)FTRACE_REGS_ADDR;
+ else
+ return (unsigned long)FTRACE_ADDR;
+}
+
static int
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
@@ -1828,12 +1794,12 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
unsigned long ftrace_addr;
int ret;
- ret = ftrace_update_record(rec, enable);
+ ftrace_addr = ftrace_get_addr_new(rec);
- if (rec->flags & FTRACE_FL_REGS)
- ftrace_addr = (unsigned long)FTRACE_REGS_ADDR;
- else
- ftrace_addr = (unsigned long)FTRACE_ADDR;
+ /* This needs to be done before we call ftrace_update_record */
+ ftrace_old_addr = ftrace_get_addr_curr(rec);
+
+ ret = ftrace_update_record(rec, enable);
switch (ret) {
case FTRACE_UPDATE_IGNORE:
@@ -1845,13 +1811,7 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
case FTRACE_UPDATE_MAKE_NOP:
return ftrace_make_nop(NULL, rec, ftrace_addr);
- case FTRACE_UPDATE_MODIFY_CALL_REGS:
case FTRACE_UPDATE_MODIFY_CALL:
- if (rec->flags & FTRACE_FL_REGS)
- ftrace_old_addr = (unsigned long)FTRACE_ADDR;
- else
- ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR;
-
return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
}
@@ -2115,7 +2075,6 @@ static void ftrace_startup_enable(int command)
static int ftrace_startup(struct ftrace_ops *ops, int command)
{
- bool hash_enable = true;
int ret;
if (unlikely(ftrace_disabled))
@@ -2128,18 +2087,9 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
ftrace_start_up++;
command |= FTRACE_UPDATE_CALLS;
- /* ops marked global share the filter hashes */
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ops = &global_ops;
- /* Don't update hash if global is already set */
- if (global_start_up)
- hash_enable = false;
- global_start_up++;
- }
-
ops->flags |= FTRACE_OPS_FL_ENABLED;
- if (hash_enable)
- ftrace_hash_rec_enable(ops, 1);
+
+ ftrace_hash_rec_enable(ops, 1);
ftrace_startup_enable(command);
@@ -2148,7 +2098,6 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
static int ftrace_shutdown(struct ftrace_ops *ops, int command)
{
- bool hash_disable = true;
int ret;
if (unlikely(ftrace_disabled))
@@ -2166,21 +2115,9 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
*/
WARN_ON_ONCE(ftrace_start_up < 0);
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ops = &global_ops;
- global_start_up--;
- WARN_ON_ONCE(global_start_up < 0);
- /* Don't update hash if global still has users */
- if (global_start_up) {
- WARN_ON_ONCE(!ftrace_start_up);
- hash_disable = false;
- }
- }
+ ftrace_hash_rec_disable(ops, 1);
- if (hash_disable)
- ftrace_hash_rec_disable(ops, 1);
-
- if (ops != &global_ops || !global_start_up)
+ if (!global_start_up)
ops->flags &= ~FTRACE_OPS_FL_ENABLED;
command |= FTRACE_UPDATE_CALLS;
@@ -3524,10 +3461,6 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
struct ftrace_hash *hash;
int ret;
- /* All global ops uses the global ops filters */
- if (ops->flags & FTRACE_OPS_FL_GLOBAL)
- ops = &global_ops;
-
if (unlikely(ftrace_disabled))
return -ENODEV;
@@ -3639,8 +3572,7 @@ int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
}
EXPORT_SYMBOL_GPL(ftrace_set_notrace);
/**
- * ftrace_set_filter - set a function to filter on in ftrace
- * @ops - the ops to set the filter with
+ * ftrace_set_global_filter - set a function to filter on with global tracers
* @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.
@@ -3655,8 +3587,7 @@ void ftrace_set_global_filter(unsigned char *buf, int len, int reset)
EXPORT_SYMBOL_GPL(ftrace_set_global_filter);
/**
- * ftrace_set_notrace - set a function to not trace in ftrace
- * @ops - the ops to set the notrace filter with
+ * ftrace_set_global_notrace - set a function to not trace with global tracers
* @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.
@@ -4330,16 +4261,11 @@ static void ftrace_init_module(struct module *mod,
ftrace_process_locs(mod, start, end);
}
-static int ftrace_module_notify_enter(struct notifier_block *self,
- unsigned long val, void *data)
+void ftrace_module_init(struct module *mod)
{
- struct module *mod = data;
-
- if (val == MODULE_STATE_COMING)
- ftrace_init_module(mod, mod->ftrace_callsites,
- mod->ftrace_callsites +
- mod->num_ftrace_callsites);
- return 0;
+ ftrace_init_module(mod, mod->ftrace_callsites,
+ mod->ftrace_callsites +
+ mod->num_ftrace_callsites);
}
static int ftrace_module_notify_exit(struct notifier_block *self,
@@ -4353,11 +4279,6 @@ static int ftrace_module_notify_exit(struct notifier_block *self,
return 0;
}
#else
-static int ftrace_module_notify_enter(struct notifier_block *self,
- unsigned long val, void *data)
-{
- return 0;
-}
static int ftrace_module_notify_exit(struct notifier_block *self,
unsigned long val, void *data)
{
@@ -4365,11 +4286,6 @@ static int ftrace_module_notify_exit(struct notifier_block *self,
}
#endif /* CONFIG_MODULES */
-struct notifier_block ftrace_module_enter_nb = {
- .notifier_call = ftrace_module_notify_enter,
- .priority = INT_MAX, /* Run before anything that can use kprobes */
-};
-
struct notifier_block ftrace_module_exit_nb = {
.notifier_call = ftrace_module_notify_exit,
.priority = INT_MIN, /* Run after anything that can remove kprobes */
@@ -4403,10 +4319,6 @@ void __init ftrace_init(void)
__start_mcount_loc,
__stop_mcount_loc);
- ret = register_module_notifier(&ftrace_module_enter_nb);
- if (ret)
- pr_warning("Failed to register trace ftrace module enter notifier\n");
-
ret = register_module_notifier(&ftrace_module_exit_nb);
if (ret)
pr_warning("Failed to register trace ftrace module exit notifier\n");
@@ -4462,6 +4374,34 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
#endif /* CONFIG_DYNAMIC_FTRACE */
+__init void ftrace_init_global_array_ops(struct trace_array *tr)
+{
+ tr->ops = &global_ops;
+ tr->ops->private = tr;
+}
+
+void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func)
+{
+ /* If we filter on pids, update to use the pid function */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
+ if (WARN_ON(tr->ops->func != ftrace_stub))
+ printk("ftrace ops had %pS for function\n",
+ tr->ops->func);
+ /* Only the top level instance does pid tracing */
+ if (!list_empty(&ftrace_pids)) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
+ }
+ tr->ops->func = func;
+ tr->ops->private = tr;
+}
+
+void ftrace_reset_array_ops(struct trace_array *tr)
+{
+ tr->ops->func = ftrace_stub;
+}
+
static void
ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
@@ -4520,9 +4460,16 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
*/
preempt_disable_notrace();
do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (ftrace_ops_test(op, ip, regs))
+ if (ftrace_ops_test(op, ip, regs)) {
+ if (WARN_ON(!op->func)) {
+ function_trace_stop = 1;
+ printk("op=%p %pS\n", op, op);
+ goto out;
+ }
op->func(ip, parent_ip, op, regs);
+ }
} while_for_each_ftrace_op(op);
+out:
preempt_enable_notrace();
trace_clear_recursion(bit);
}
@@ -4927,7 +4874,6 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static int ftrace_graph_active;
-static struct notifier_block ftrace_suspend_notifier;
int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
{
@@ -5073,13 +5019,6 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
return NOTIFY_DONE;
}
-/* Just a place holder for function graph */
-static struct ftrace_ops fgraph_ops __read_mostly = {
- .func = ftrace_stub,
- .flags = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_GLOBAL |
- FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
{
if (!ftrace_ops_test(&global_ops, trace->func, NULL))
@@ -5104,6 +5043,10 @@ static void update_function_graph_func(void)
ftrace_graph_entry = ftrace_graph_entry_test;
}
+static struct notifier_block ftrace_suspend_notifier = {
+ .notifier_call = ftrace_suspend_notifier_call,
+};
+
int register_ftrace_graph(trace_func_graph_ret_t retfunc,
trace_func_graph_ent_t entryfunc)
{
@@ -5117,7 +5060,6 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
goto out;
}
- ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
register_pm_notifier(&ftrace_suspend_notifier);
ftrace_graph_active++;
@@ -5139,7 +5081,10 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
ftrace_graph_entry = ftrace_graph_entry_test;
update_function_graph_func();
- ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET);
+ /* Function graph doesn't use the .func field of global_ops */
+ global_ops.flags |= FTRACE_OPS_FL_STUB;
+
+ ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
out:
mutex_unlock(&ftrace_lock);
@@ -5157,7 +5102,8 @@ void unregister_ftrace_graph(void)
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
__ftrace_graph_entry = ftrace_graph_entry_stub;
- ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET);
+ ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
+ global_ops.flags &= ~FTRACE_OPS_FL_STUB;
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);