1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * fill_buf benchmark 4 * 5 * Copyright (C) 2018 Intel Corporation 6 * 7 * Authors: 8 * Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>, 9 * Fenghua Yu <fenghua.yu@intel.com> 10 */ 11 #include <stdio.h> 12 #include <unistd.h> 13 #include <stdlib.h> 14 #include <sys/types.h> 15 #include <sys/wait.h> 16 #include <inttypes.h> 17 #include <string.h> 18 19 #include "resctrl.h" 20 21 #define CL_SIZE (64) 22 #define PAGE_SIZE (4 * 1024) 23 #define MB (1024 * 1024) 24 25 static void sb(void) 26 { 27 #if defined(__i386) || defined(__x86_64) 28 asm volatile("sfence\n\t" 29 : : : "memory"); 30 #endif 31 } 32 33 static void cl_flush(void *p) 34 { 35 #if defined(__i386) || defined(__x86_64) 36 asm volatile("clflush (%0)\n\t" 37 : : "r"(p) : "memory"); 38 #endif 39 } 40 41 static void mem_flush(unsigned char *buf, size_t buf_size) 42 { 43 unsigned char *cp = buf; 44 size_t i = 0; 45 46 buf_size = buf_size / CL_SIZE; /* mem size in cache lines */ 47 48 for (i = 0; i < buf_size; i++) 49 cl_flush(&cp[i * CL_SIZE]); 50 51 sb(); 52 } 53 54 static void *malloc_and_init_memory(size_t buf_size) 55 { 56 void *p = NULL; 57 uint64_t *p64; 58 size_t s64; 59 int ret; 60 61 ret = posix_memalign(&p, PAGE_SIZE, buf_size); 62 if (ret < 0) 63 return NULL; 64 65 p64 = (uint64_t *)p; 66 s64 = buf_size / sizeof(uint64_t); 67 68 while (s64 > 0) { 69 *p64 = (uint64_t)rand(); 70 p64 += (CL_SIZE / sizeof(uint64_t)); 71 s64 -= (CL_SIZE / sizeof(uint64_t)); 72 } 73 74 return p; 75 } 76 77 static int fill_one_span_read(unsigned char *buf, size_t buf_size) 78 { 79 unsigned char *end_ptr = buf + buf_size; 80 unsigned char sum, *p; 81 82 sum = 0; 83 p = buf; 84 while (p < end_ptr) { 85 sum += *p; 86 p += (CL_SIZE / 2); 87 } 88 89 return sum; 90 } 91 92 static void fill_one_span_write(unsigned char *buf, size_t buf_size) 93 { 94 unsigned char *end_ptr = buf + buf_size; 95 unsigned char *p; 96 97 p = buf; 98 while (p < end_ptr) { 99 *p = '1'; 100 p += (CL_SIZE / 2); 101 } 102 } 103 104 static int fill_cache_read(unsigned char *buf, size_t buf_size, 105 char *resctrl_val) 106 { 107 int ret = 0; 108 FILE *fp; 109 110 while (1) { 111 ret = fill_one_span_read(buf, buf_size); 112 if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR))) 113 break; 114 } 115 116 /* Consume read result so that reading memory is not optimized out. */ 117 fp = fopen("/dev/null", "w"); 118 if (!fp) { 119 perror("Unable to write to /dev/null"); 120 return -1; 121 } 122 fprintf(fp, "Sum: %d ", ret); 123 fclose(fp); 124 125 return 0; 126 } 127 128 static int fill_cache_write(unsigned char *buf, size_t buf_size, 129 char *resctrl_val) 130 { 131 while (1) { 132 fill_one_span_write(buf, buf_size); 133 if (!strncmp(resctrl_val, CAT_STR, sizeof(CAT_STR))) 134 break; 135 } 136 137 return 0; 138 } 139 140 static int fill_cache(size_t buf_size, int memflush, int op, char *resctrl_val) 141 { 142 unsigned char *buf; 143 int ret; 144 145 buf = malloc_and_init_memory(buf_size); 146 if (!buf) 147 return -1; 148 149 /* Flush the memory before using to avoid "cache hot pages" effect */ 150 if (memflush) 151 mem_flush(buf, buf_size); 152 153 if (op == 0) 154 ret = fill_cache_read(buf, buf_size, resctrl_val); 155 else 156 ret = fill_cache_write(buf, buf_size, resctrl_val); 157 158 free(buf); 159 160 if (ret) { 161 printf("\n Error in fill cache read/write...\n"); 162 return -1; 163 } 164 165 166 return 0; 167 } 168 169 int run_fill_buf(size_t span, int memflush, int op, char *resctrl_val) 170 { 171 size_t cache_size = span; 172 int ret; 173 174 ret = fill_cache(cache_size, memflush, op, resctrl_val); 175 if (ret) { 176 printf("\n Error in fill cache\n"); 177 return -1; 178 } 179 180 return 0; 181 } 182