Commit 829ec749 authored by Vasily Gorbik's avatar Vasily Gorbik
Browse files

s390/test_unwind: add ftrace test 



Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent 8a0c9705

arch/s390/lib/test_unwind.c

+59 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
#include <linux/completion.h>

#include <linux/kallsyms.h>

#include <linux/kthread.h>

#include <linux/ftrace.h>

#include <linux/module.h>

#include <linux/timer.h>

#include <linux/slab.h>
@@ -129,6 +130,7 @@ static struct unwindme *unwindme; 
#define UWM_SWITCH_STACK	0x10	/* Use call_on_stack. */

#define UWM_IRQ			0x20	/* Unwind from irq context. */

#define UWM_PGM			0x40	/* Unwind from program check handler. */

#define UWM_FTRACE		0x80	/* Unwind from ftrace handler. */



static __always_inline unsigned long get_psw_addr(void)

{
@@ -149,6 +151,57 @@ static int pgm_pre_handler(struct kprobe *p, struct pt_regs *regs) 
	return 0;

}



static void notrace __used test_unwind_ftrace_handler(unsigned long ip,

						      unsigned long parent_ip,

						      struct ftrace_ops *fops,

						      struct ftrace_regs *fregs)

{

	struct unwindme *u = (struct unwindme *)fregs->regs.gprs[2];



	u->ret = test_unwind(NULL, (u->flags & UWM_REGS) ? &fregs->regs : NULL,

			     (u->flags & UWM_SP) ? u->sp : 0);

}



static noinline int test_unwind_ftraced_func(struct unwindme *u)

{

	return READ_ONCE(u)->ret;

}



static int test_unwind_ftrace(struct unwindme *u)

{

	struct ftrace_ops *fops;

	int ret;



#ifndef CONFIG_DYNAMIC_FTRACE

	kunit_skip(current_test, "requires CONFIG_DYNAMIC_FTRACE");

	fops = NULL; /* used */

#else

	fops = kunit_kzalloc(current_test, sizeof(*fops), GFP_KERNEL);

	fops->func = test_unwind_ftrace_handler;

	fops->flags = FTRACE_OPS_FL_DYNAMIC |

		     FTRACE_OPS_FL_RECURSION |

		     FTRACE_OPS_FL_SAVE_REGS |

		     FTRACE_OPS_FL_PERMANENT;

#endif



	ret = ftrace_set_filter_ip(fops, (unsigned long)test_unwind_ftraced_func, 0, 0);

	if (ret) {

		kunit_err(current_test, "failed to set ftrace filter (%d)\n", ret);

		return -1;

	}



	ret = register_ftrace_function(fops);

	if (!ret) {

		ret = test_unwind_ftraced_func(u);

		unregister_ftrace_function(fops);

	} else {

		kunit_err(current_test, "failed to register ftrace handler (%d)\n", ret);

	}



	ftrace_set_filter_ip(fops, (unsigned long)test_unwind_ftraced_func, 1, 0);

	return ret;

}



/* This function may or may not appear in the backtrace. */

static noinline int unwindme_func4(struct unwindme *u)

{
@@ -189,6 +242,8 @@ static noinline int unwindme_func4(struct unwindme *u) 
		unregister_kprobe(&kp);

		unwindme = NULL;

		return u->ret;

	} else if (u->flags & UWM_FTRACE) {

		return test_unwind_ftrace(u);

	} else {

		struct pt_regs regs;
@@ -321,6 +376,10 @@ static const struct test_params param_list[] = { 
	TEST_WITH_FLAGS(UWM_PGM | UWM_SP),

	TEST_WITH_FLAGS(UWM_PGM | UWM_REGS),

	TEST_WITH_FLAGS(UWM_PGM | UWM_SP | UWM_REGS),

	TEST_WITH_FLAGS(UWM_FTRACE),

	TEST_WITH_FLAGS(UWM_FTRACE | UWM_SP),

	TEST_WITH_FLAGS(UWM_FTRACE | UWM_REGS),

	TEST_WITH_FLAGS(UWM_FTRACE | UWM_SP | UWM_REGS),

};



/*