Commit f03c4129 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

static_call: Add simple self-test for static calls 



Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200818135804.922581202@infradead.org
parent 1e7e4788

arch/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -106,6 +106,12 @@ config STATIC_KEYS_SELFTEST 
	help

	  Boot time self-test of the branch patching code.



config STATIC_CALL_SELFTEST

	bool "Static call selftest"

	depends on HAVE_STATIC_CALL

	help

	  Boot time self-test of the call patching code.



config OPTPROBES

	def_bool y

	depends on KPROBES && HAVE_OPTPROBES

kernel/static_call.c

+43 −0
Original line number Diff line number Diff line
@@ -369,3 +369,46 @@ static void __init static_call_init(void) 
#endif

}

early_initcall(static_call_init);



#ifdef CONFIG_STATIC_CALL_SELFTEST



static int func_a(int x)

{

	return x+1;

}



static int func_b(int x)

{

	return x+2;

}



DEFINE_STATIC_CALL(sc_selftest, func_a);



static struct static_call_data {

      int (*func)(int);

      int val;

      int expect;

} static_call_data [] __initdata = {

      { NULL,   2, 3 },

      { func_b, 2, 4 },

      { func_a, 2, 3 }

};



static int __init test_static_call_init(void)

{

      int i;



      for (i = 0; i < ARRAY_SIZE(static_call_data); i++ ) {

	      struct static_call_data *scd = &static_call_data[i];



              if (scd->func)

                      static_call_update(sc_selftest, scd->func);



              WARN_ON(static_call(sc_selftest)(scd->val) != scd->expect);

      }



      return 0;

}

early_initcall(test_static_call_init);



#endif /* CONFIG_STATIC_CALL_SELFTEST */