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Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c68
1 files changed, 21 insertions, 47 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4771732037ee..157d4f68b0e0 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -62,8 +62,6 @@ int function_trace_stop;
static int ftrace_disabled __read_mostly;
static DEFINE_MUTEX(ftrace_lock);
-static DEFINE_MUTEX(ftrace_sysctl_lock);
-static DEFINE_MUTEX(ftrace_start_lock);
static struct ftrace_ops ftrace_list_end __read_mostly =
{
@@ -134,8 +132,6 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip)
static int __register_ftrace_function(struct ftrace_ops *ops)
{
- mutex_lock(&ftrace_lock);
-
ops->next = ftrace_list;
/*
* We are entering ops into the ftrace_list but another
@@ -171,17 +167,12 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
#endif
}
- mutex_unlock(&ftrace_lock);
-
return 0;
}
static int __unregister_ftrace_function(struct ftrace_ops *ops)
{
struct ftrace_ops **p;
- int ret = 0;
-
- mutex_lock(&ftrace_lock);
/*
* If we are removing the last function, then simply point
@@ -190,17 +181,15 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
if (ftrace_list == ops && ops->next == &ftrace_list_end) {
ftrace_trace_function = ftrace_stub;
ftrace_list = &ftrace_list_end;
- goto out;
+ return 0;
}
for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next)
if (*p == ops)
break;
- if (*p != ops) {
- ret = -1;
- goto out;
- }
+ if (*p != ops)
+ return -1;
*p = (*p)->next;
@@ -221,10 +210,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
}
}
- out:
- mutex_unlock(&ftrace_lock);
-
- return ret;
+ return 0;
}
static void ftrace_update_pid_func(void)
@@ -622,13 +608,10 @@ static void ftrace_startup(int command)
if (unlikely(ftrace_disabled))
return;
- mutex_lock(&ftrace_start_lock);
ftrace_start_up++;
command |= FTRACE_ENABLE_CALLS;
ftrace_startup_enable(command);
-
- mutex_unlock(&ftrace_start_lock);
}
static void ftrace_shutdown(int command)
@@ -636,7 +619,6 @@ static void ftrace_shutdown(int command)
if (unlikely(ftrace_disabled))
return;
- mutex_lock(&ftrace_start_lock);
ftrace_start_up--;
if (!ftrace_start_up)
command |= FTRACE_DISABLE_CALLS;
@@ -647,11 +629,9 @@ static void ftrace_shutdown(int command)
}
if (!command || !ftrace_enabled)
- goto out;
+ return;
ftrace_run_update_code(command);
- out:
- mutex_unlock(&ftrace_start_lock);
}
static void ftrace_startup_sysctl(void)
@@ -661,7 +641,6 @@ static void ftrace_startup_sysctl(void)
if (unlikely(ftrace_disabled))
return;
- mutex_lock(&ftrace_start_lock);
/* Force update next time */
saved_ftrace_func = NULL;
/* ftrace_start_up is true if we want ftrace running */
@@ -669,7 +648,6 @@ static void ftrace_startup_sysctl(void)
command |= FTRACE_ENABLE_CALLS;
ftrace_run_update_code(command);
- mutex_unlock(&ftrace_start_lock);
}
static void ftrace_shutdown_sysctl(void)
@@ -679,13 +657,11 @@ static void ftrace_shutdown_sysctl(void)
if (unlikely(ftrace_disabled))
return;
- mutex_lock(&ftrace_start_lock);
/* ftrace_start_up is true if ftrace is running */
if (ftrace_start_up)
command |= FTRACE_DISABLE_CALLS;
ftrace_run_update_code(command);
- mutex_unlock(&ftrace_start_lock);
}
static cycle_t ftrace_update_time;
@@ -1502,12 +1478,10 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
}
- mutex_lock(&ftrace_sysctl_lock);
- mutex_lock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
if (ftrace_start_up && ftrace_enabled)
ftrace_run_update_code(FTRACE_ENABLE_CALLS);
- mutex_unlock(&ftrace_start_lock);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
kfree(iter);
mutex_unlock(&ftrace_regex_lock);
@@ -1824,7 +1798,7 @@ static int ftrace_convert_nops(struct module *mod,
unsigned long addr;
unsigned long flags;
- mutex_lock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
p = start;
while (p < end) {
addr = ftrace_call_adjust(*p++);
@@ -1843,7 +1817,7 @@ static int ftrace_convert_nops(struct module *mod,
local_irq_save(flags);
ftrace_update_code(mod);
local_irq_restore(flags);
- mutex_unlock(&ftrace_start_lock);
+ mutex_unlock(&ftrace_lock);
return 0;
}
@@ -2016,7 +1990,7 @@ ftrace_pid_write(struct file *filp, const char __user *ubuf,
if (ret < 0)
return ret;
- mutex_lock(&ftrace_start_lock);
+ mutex_lock(&ftrace_lock);
if (val < 0) {
/* disable pid tracing */
if (!ftrace_pid_trace)
@@ -2055,7 +2029,7 @@ ftrace_pid_write(struct file *filp, const char __user *ubuf,
ftrace_startup_enable(0);
out:
- mutex_unlock(&ftrace_start_lock);
+ mutex_unlock(&ftrace_lock);
return cnt;
}
@@ -2118,12 +2092,12 @@ int register_ftrace_function(struct ftrace_ops *ops)
if (unlikely(ftrace_disabled))
return -1;
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
ret = __register_ftrace_function(ops);
ftrace_startup(0);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
@@ -2137,10 +2111,10 @@ int unregister_ftrace_function(struct ftrace_ops *ops)
{
int ret;
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
ret = __unregister_ftrace_function(ops);
ftrace_shutdown(0);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
@@ -2155,7 +2129,7 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
if (unlikely(ftrace_disabled))
return -ENODEV;
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
@@ -2184,7 +2158,7 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
}
out:
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
@@ -2296,7 +2270,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
{
int ret = 0;
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
register_pm_notifier(&ftrace_suspend_notifier);
@@ -2314,13 +2288,13 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
ftrace_startup(FTRACE_START_FUNC_RET);
out:
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
return ret;
}
void unregister_ftrace_graph(void)
{
- mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftrace_lock);
atomic_dec(&ftrace_graph_active);
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
@@ -2328,7 +2302,7 @@ void unregister_ftrace_graph(void)
ftrace_shutdown(FTRACE_STOP_FUNC_RET);
unregister_pm_notifier(&ftrace_suspend_notifier);
- mutex_unlock(&ftrace_sysctl_lock);
+ mutex_unlock(&ftrace_lock);
}
/* Allocate a return stack for newly created task */
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