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Diffstat (limited to 'kernel/trace/trace_stack.c')
-rw-r--r--kernel/trace/trace_stack.c32
1 files changed, 25 insertions, 7 deletions
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 5a48dba912ea..0aa2514a6593 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -32,7 +32,7 @@ static arch_spinlock_t stack_trace_max_lock =
DEFINE_PER_CPU(int, disable_stack_tracer);
static DEFINE_MUTEX(stack_sysctl_mutex);
-int stack_tracer_enabled;
+static int stack_tracer_enabled;
static void print_max_stack(void)
{
@@ -514,26 +514,24 @@ static const struct file_operations stack_trace_filter_fops = {
#endif /* CONFIG_DYNAMIC_FTRACE */
int
-stack_trace_sysctl(struct ctl_table *table, int write, void *buffer,
+stack_trace_sysctl(const struct ctl_table *table, int write, void *buffer,
size_t *lenp, loff_t *ppos)
{
int was_enabled;
int ret;
- mutex_lock(&stack_sysctl_mutex);
+ guard(mutex)(&stack_sysctl_mutex);
was_enabled = !!stack_tracer_enabled;
ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (ret || !write || (was_enabled == !!stack_tracer_enabled))
- goto out;
+ return ret;
if (stack_tracer_enabled)
register_ftrace_function(&trace_ops);
else
unregister_ftrace_function(&trace_ops);
- out:
- mutex_unlock(&stack_sysctl_mutex);
return ret;
}
@@ -544,7 +542,7 @@ static __init int enable_stacktrace(char *str)
int len;
if ((len = str_has_prefix(str, "_filter=")))
- strncpy(stack_trace_filter_buf, str + len, COMMAND_LINE_SIZE);
+ strscpy(stack_trace_filter_buf, str + len);
stack_tracer_enabled = 1;
return 1;
@@ -580,3 +578,23 @@ static __init int stack_trace_init(void)
}
device_initcall(stack_trace_init);
+
+
+static const struct ctl_table trace_stack_sysctl_table[] = {
+ {
+ .procname = "stack_tracer_enabled",
+ .data = &stack_tracer_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = stack_trace_sysctl,
+ },
+};
+
+static int __init init_trace_stack_sysctls(void)
+{
+ register_sysctl_init("kernel", trace_stack_sysctl_table);
+ return 0;
+}
+subsys_initcall(init_trace_stack_sysctls);
+
+