Commit f8b7d2b4 authored by Luis Chamberlain's avatar Luis Chamberlain
Browse files

ftrace: fix building with SYSCTL=n but DYNAMIC_FTRACE=y 



One can enable dyanmic tracing but disable sysctls.
When this is doen we get the compile kernel warning:

  CC      kernel/trace/ftrace.o
kernel/trace/ftrace.c:3086:13: warning: ‘ftrace_shutdown_sysctl’ defined
but not used [-Wunused-function]
 3086 | static void ftrace_shutdown_sysctl(void)
      |             ^~~~~~~~~~~~~~~~~~~~~~
kernel/trace/ftrace.c:3068:13: warning: ‘ftrace_startup_sysctl’ defined
but not used [-Wunused-function]
 3068 | static void ftrace_startup_sysctl(void)

When CONFIG_DYNAMIC_FTRACE=n the ftrace_startup_sysctl() and
routines ftrace_shutdown_sysctl() still compiles, so these
are actually more just used for when SYSCTL=y.

Fix this then by just moving these routines to when sysctls
are enabled.

Fixes: 7cde53da38a3 ("ftrace: move sysctl_ftrace_enabled to ftrace.c")
Reported-by: default avatarkernel test robot <lkp@intel.com>
Acked-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
parent 5d79fa0d

kernel/trace/ftrace.c

+34 −37
Original line number Diff line number Diff line
@@ -3065,40 +3065,6 @@ int ftrace_shutdown(struct ftrace_ops *ops, int command) 
	return 0;

}



static void ftrace_startup_sysctl(void)

{

	int command;



	if (unlikely(ftrace_disabled))

		return;



	/* Force update next time */

	saved_ftrace_func = NULL;

	/* ftrace_start_up is true if we want ftrace running */

	if (ftrace_start_up) {

		command = FTRACE_UPDATE_CALLS;

		if (ftrace_graph_active)

			command |= FTRACE_START_FUNC_RET;

		ftrace_startup_enable(command);

	}

}



static void ftrace_shutdown_sysctl(void)

{

	int command;



	if (unlikely(ftrace_disabled))

		return;



	/* ftrace_start_up is true if ftrace is running */

	if (ftrace_start_up) {

		command = FTRACE_DISABLE_CALLS;

		if (ftrace_graph_active)

			command |= FTRACE_STOP_FUNC_RET;

		ftrace_run_update_code(command);

	}

}



static u64		ftrace_update_time;

unsigned long		ftrace_update_tot_cnt;

unsigned long		ftrace_number_of_pages;
@@ -7267,9 +7233,6 @@ core_initcall(ftrace_nodyn_init); 
static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; }

static inline void ftrace_startup_all(int command) { }



# define ftrace_startup_sysctl()	do { } while (0)

# define ftrace_shutdown_sysctl()	do { } while (0)



static void ftrace_update_trampoline(struct ftrace_ops *ops)

{

}
@@ -7910,6 +7873,40 @@ int unregister_ftrace_function(struct ftrace_ops *ops) 
EXPORT_SYMBOL_GPL(unregister_ftrace_function);



#ifdef CONFIG_SYSCTL

static void ftrace_startup_sysctl(void)

{

	int command;



	if (unlikely(ftrace_disabled))

		return;



	/* Force update next time */

	saved_ftrace_func = NULL;

	/* ftrace_start_up is true if we want ftrace running */

	if (ftrace_start_up) {

		command = FTRACE_UPDATE_CALLS;

		if (ftrace_graph_active)

			command |= FTRACE_START_FUNC_RET;

		ftrace_startup_enable(command);

	}

}



static void ftrace_shutdown_sysctl(void)

{

	int command;



	if (unlikely(ftrace_disabled))

		return;



	/* ftrace_start_up is true if ftrace is running */

	if (ftrace_start_up) {

		command = FTRACE_DISABLE_CALLS;

		if (ftrace_graph_active)

			command |= FTRACE_STOP_FUNC_RET;

		ftrace_run_update_code(command);

	}

}



static bool is_permanent_ops_registered(void)

{

	struct ftrace_ops *op;