function-graph: use int instead of atomic for ftrace_graph_active (597af815) · Commits · 戴 / test

kernel/trace/ftrace.c

+7 −7

Original line number	Diff line number	Diff line
		@@ -3092,7 +3092,7 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,

		#ifdef CONFIG_FUNCTION_GRAPH_TRACER

		static atomic_t ftrace_graph_active;
		static int ftrace_graph_active;
		static struct notifier_block ftrace_suspend_notifier;

		int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
		@@ -3244,7 +3244,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
		mutex_lock(&ftrace_lock);

		/* we currently allow only one tracer registered at a time */
		if (atomic_read(&ftrace_graph_active)) {
		if (ftrace_graph_active) {
		ret = -EBUSY;
		goto out;
		}
		@@ -3252,10 +3252,10 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
		ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
		register_pm_notifier(&ftrace_suspend_notifier);

		atomic_inc(&ftrace_graph_active);
		ftrace_graph_active++;
		ret = start_graph_tracing();
		if (ret) {
		atomic_dec(&ftrace_graph_active);
		ftrace_graph_active--;
		goto out;
		}

		@@ -3273,10 +3273,10 @@ void unregister_ftrace_graph(void)
		{
		mutex_lock(&ftrace_lock);

		if (!unlikely(atomic_read(&ftrace_graph_active)))
		if (unlikely(!ftrace_graph_active))
		goto out;

		atomic_dec(&ftrace_graph_active);
		ftrace_graph_active--;
		unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
		ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
		ftrace_graph_entry = ftrace_graph_entry_stub;
		@@ -3290,7 +3290,7 @@ void unregister_ftrace_graph(void)
		/* Allocate a return stack for newly created task */
		void ftrace_graph_init_task(struct task_struct *t)
		{
		if (atomic_read(&ftrace_graph_active)) {
		if (ftrace_graph_active) {
		t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH
		* sizeof(struct ftrace_ret_stack),
		GFP_KERNEL);

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