// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (C) 2020 Intel Corporation */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/cleanup.h>#include <linux/init.h>#include <linux/module.h>#include <linux/printk.h>#include <linux/slab.h> /* a tiny module only meant to test * *   set/clear_bit *   get_count_order/long */ /* use an enum because that's the most common BITMAP usage */enum bitops_fun {	BITOPS_4 = 4,	BITOPS_7 = 7,	BITOPS_11 = 11,	BITOPS_31 = 31,	BITOPS_88 = 88,	BITOPS_LAST = 255,	BITOPS_LENGTH = 256}; static DECLARE_BITMAP(g_bitmap, BITOPS_LENGTH); static unsigned int order_comb[][2] = {	{0x00000003,  2},	{0x00000004,  2},	{0x00001fff, 13},	{0x00002000, 13},	{0x50000000, 31},	{0x80000000, 31},	{0x80003000, 32},}; #ifdef CONFIG_64BITstatic unsigned long order_comb_long[][2] = {	{0x0000000300000000, 34},	{0x0000000400000000, 34},	{0x00001fff00000000, 45},	{0x0000200000000000, 45},	{0x5000000000000000, 63},	{0x8000000000000000, 63},	{0x8000300000000000, 64},};#endif static int __init test_fns(void){	static volatile __always_used unsigned long tmp __initdata;	unsigned long *buf __free(kfree) = NULL;	unsigned int i, n;	ktime_t time; 	buf = kmalloc_array(10000, sizeof(unsigned long), GFP_KERNEL);	if (!buf)		return -ENOMEM; 	get_random_bytes(buf, 10000 * sizeof(unsigned long));	time = ktime_get(); 	for (n = 0; n < BITS_PER_LONG; n++)		for (i = 0; i < 10000; i++)			tmp = fns(buf[i], n); 	time = ktime_get() - time;	pr_err("fns:  %18llu ns\n", time); 	return 0;} static int __init test_bitops_startup(void){	int i, bit_set; 	pr_info("Starting bitops test\n");	set_bit(BITOPS_4, g_bitmap);	set_bit(BITOPS_7, g_bitmap);	set_bit(BITOPS_11, g_bitmap);	set_bit(BITOPS_31, g_bitmap);	set_bit(BITOPS_88, g_bitmap); 	for (i = 0; i < ARRAY_SIZE(order_comb); i++) {		if (order_comb[i][1] != get_count_order(order_comb[i][0]))			pr_warn("get_count_order wrong for %x\n",				       order_comb[i][0]);	} 	for (i = 0; i < ARRAY_SIZE(order_comb); i++) {		if (order_comb[i][1] != get_count_order_long(order_comb[i][0]))			pr_warn("get_count_order_long wrong for %x\n",				       order_comb[i][0]);	} #ifdef CONFIG_64BIT	for (i = 0; i < ARRAY_SIZE(order_comb_long); i++) {		if (order_comb_long[i][1] !=			       get_count_order_long(order_comb_long[i][0]))			pr_warn("get_count_order_long wrong for %lx\n",				       order_comb_long[i][0]);	}#endif 	barrier(); 	clear_bit(BITOPS_4, g_bitmap);	clear_bit(BITOPS_7, g_bitmap);	clear_bit(BITOPS_11, g_bitmap);	clear_bit(BITOPS_31, g_bitmap);	clear_bit(BITOPS_88, g_bitmap); 	bit_set = find_first_bit(g_bitmap, BITOPS_LAST);	if (bit_set != BITOPS_LAST)		pr_err("ERROR: FOUND SET BIT %d\n", bit_set); 	test_fns(); 	pr_info("Completed bitops test\n"); 	return 0;} static void __exit test_bitops_unstartup(void){} module_init(test_bitops_startup);module_exit(test_bitops_unstartup); MODULE_AUTHOR("Jesse Brandeburg <jesse.brandeburg@intel.com>, Wei Yang <richard.weiyang@gmail.com>");MODULE_LICENSE("GPL");MODULE_DESCRIPTION("Bit testing module");