1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2020 Intel Corporation 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/cleanup.h> 9 #include <linux/init.h> 10 #include <linux/module.h> 11 #include <linux/printk.h> 12 #include <linux/slab.h> 13 14 /* a tiny module only meant to test 15 * 16 * set/clear_bit 17 * get_count_order/long 18 */ 19 20 /* use an enum because that's the most common BITMAP usage */ 21 enum bitops_fun { 22 BITOPS_4 = 4, 23 BITOPS_7 = 7, 24 BITOPS_11 = 11, 25 BITOPS_31 = 31, 26 BITOPS_88 = 88, 27 BITOPS_LAST = 255, 28 BITOPS_LENGTH = 256 29 }; 30 31 static DECLARE_BITMAP(g_bitmap, BITOPS_LENGTH); 32 33 static unsigned int order_comb[][2] = { 34 {0x00000003, 2}, 35 {0x00000004, 2}, 36 {0x00001fff, 13}, 37 {0x00002000, 13}, 38 {0x50000000, 31}, 39 {0x80000000, 31}, 40 {0x80003000, 32}, 41 }; 42 43 #ifdef CONFIG_64BIT 44 static unsigned long order_comb_long[][2] = { 45 {0x0000000300000000, 34}, 46 {0x0000000400000000, 34}, 47 {0x00001fff00000000, 45}, 48 {0x0000200000000000, 45}, 49 {0x5000000000000000, 63}, 50 {0x8000000000000000, 63}, 51 {0x8000300000000000, 64}, 52 }; 53 #endif 54 55 static int __init test_fns(void) 56 { 57 static volatile __always_used unsigned long tmp __initdata; 58 unsigned long *buf __free(kfree) = NULL; 59 unsigned int i, n; 60 ktime_t time; 61 62 buf = kmalloc_array(10000, sizeof(unsigned long), GFP_KERNEL); 63 if (!buf) 64 return -ENOMEM; 65 66 get_random_bytes(buf, 10000 * sizeof(unsigned long)); 67 time = ktime_get(); 68 69 for (n = 0; n < BITS_PER_LONG; n++) 70 for (i = 0; i < 10000; i++) 71 tmp = fns(buf[i], n); 72 73 time = ktime_get() - time; 74 pr_err("fns: %18llu ns\n", time); 75 76 return 0; 77 } 78 79 static int __init test_bitops_startup(void) 80 { 81 int i, bit_set; 82 83 pr_info("Starting bitops test\n"); 84 set_bit(BITOPS_4, g_bitmap); 85 set_bit(BITOPS_7, g_bitmap); 86 set_bit(BITOPS_11, g_bitmap); 87 set_bit(BITOPS_31, g_bitmap); 88 set_bit(BITOPS_88, g_bitmap); 89 90 for (i = 0; i < ARRAY_SIZE(order_comb); i++) { 91 if (order_comb[i][1] != get_count_order(order_comb[i][0])) 92 pr_warn("get_count_order wrong for %x\n", 93 order_comb[i][0]); 94 } 95 96 for (i = 0; i < ARRAY_SIZE(order_comb); i++) { 97 if (order_comb[i][1] != get_count_order_long(order_comb[i][0])) 98 pr_warn("get_count_order_long wrong for %x\n", 99 order_comb[i][0]); 100 } 101 102 #ifdef CONFIG_64BIT 103 for (i = 0; i < ARRAY_SIZE(order_comb_long); i++) { 104 if (order_comb_long[i][1] != 105 get_count_order_long(order_comb_long[i][0])) 106 pr_warn("get_count_order_long wrong for %lx\n", 107 order_comb_long[i][0]); 108 } 109 #endif 110 111 barrier(); 112 113 clear_bit(BITOPS_4, g_bitmap); 114 clear_bit(BITOPS_7, g_bitmap); 115 clear_bit(BITOPS_11, g_bitmap); 116 clear_bit(BITOPS_31, g_bitmap); 117 clear_bit(BITOPS_88, g_bitmap); 118 119 bit_set = find_first_bit(g_bitmap, BITOPS_LAST); 120 if (bit_set != BITOPS_LAST) 121 pr_err("ERROR: FOUND SET BIT %d\n", bit_set); 122 123 test_fns(); 124 125 pr_info("Completed bitops test\n"); 126 127 return 0; 128 } 129 130 static void __exit test_bitops_unstartup(void) 131 { 132 } 133 134 module_init(test_bitops_startup); 135 module_exit(test_bitops_unstartup); 136 137 MODULE_AUTHOR("Jesse Brandeburg <jesse.brandeburg@intel.com>, Wei Yang <richard.weiyang@gmail.com>"); 138 MODULE_LICENSE("GPL"); 139 MODULE_DESCRIPTION("Bit testing module"); 140