1 // SPDX-License-Identifier: GPL-2.0 2 #include <errno.h> 3 #include <string.h> 4 #include <regex.h> 5 #include <linux/zalloc.h> 6 7 #include "../../perf-sys.h" 8 #include "../../util/perf_regs.h" 9 #include "../../util/debug.h" 10 #include "../../util/event.h" 11 12 const struct sample_reg sample_reg_masks[] = { 13 SMPL_REG(AX, PERF_REG_X86_AX), 14 SMPL_REG(BX, PERF_REG_X86_BX), 15 SMPL_REG(CX, PERF_REG_X86_CX), 16 SMPL_REG(DX, PERF_REG_X86_DX), 17 SMPL_REG(SI, PERF_REG_X86_SI), 18 SMPL_REG(DI, PERF_REG_X86_DI), 19 SMPL_REG(BP, PERF_REG_X86_BP), 20 SMPL_REG(SP, PERF_REG_X86_SP), 21 SMPL_REG(IP, PERF_REG_X86_IP), 22 SMPL_REG(FLAGS, PERF_REG_X86_FLAGS), 23 SMPL_REG(CS, PERF_REG_X86_CS), 24 SMPL_REG(SS, PERF_REG_X86_SS), 25 #ifdef HAVE_ARCH_X86_64_SUPPORT 26 SMPL_REG(R8, PERF_REG_X86_R8), 27 SMPL_REG(R9, PERF_REG_X86_R9), 28 SMPL_REG(R10, PERF_REG_X86_R10), 29 SMPL_REG(R11, PERF_REG_X86_R11), 30 SMPL_REG(R12, PERF_REG_X86_R12), 31 SMPL_REG(R13, PERF_REG_X86_R13), 32 SMPL_REG(R14, PERF_REG_X86_R14), 33 SMPL_REG(R15, PERF_REG_X86_R15), 34 #endif 35 SMPL_REG2(XMM0, PERF_REG_X86_XMM0), 36 SMPL_REG2(XMM1, PERF_REG_X86_XMM1), 37 SMPL_REG2(XMM2, PERF_REG_X86_XMM2), 38 SMPL_REG2(XMM3, PERF_REG_X86_XMM3), 39 SMPL_REG2(XMM4, PERF_REG_X86_XMM4), 40 SMPL_REG2(XMM5, PERF_REG_X86_XMM5), 41 SMPL_REG2(XMM6, PERF_REG_X86_XMM6), 42 SMPL_REG2(XMM7, PERF_REG_X86_XMM7), 43 SMPL_REG2(XMM8, PERF_REG_X86_XMM8), 44 SMPL_REG2(XMM9, PERF_REG_X86_XMM9), 45 SMPL_REG2(XMM10, PERF_REG_X86_XMM10), 46 SMPL_REG2(XMM11, PERF_REG_X86_XMM11), 47 SMPL_REG2(XMM12, PERF_REG_X86_XMM12), 48 SMPL_REG2(XMM13, PERF_REG_X86_XMM13), 49 SMPL_REG2(XMM14, PERF_REG_X86_XMM14), 50 SMPL_REG2(XMM15, PERF_REG_X86_XMM15), 51 SMPL_REG_END 52 }; 53 54 struct sdt_name_reg { 55 const char *sdt_name; 56 const char *uprobe_name; 57 }; 58 #define SDT_NAME_REG(n, m) {.sdt_name = "%" #n, .uprobe_name = "%" #m} 59 #define SDT_NAME_REG_END {.sdt_name = NULL, .uprobe_name = NULL} 60 61 static const struct sdt_name_reg sdt_reg_tbl[] = { 62 SDT_NAME_REG(eax, ax), 63 SDT_NAME_REG(rax, ax), 64 SDT_NAME_REG(al, ax), 65 SDT_NAME_REG(ah, ax), 66 SDT_NAME_REG(ebx, bx), 67 SDT_NAME_REG(rbx, bx), 68 SDT_NAME_REG(bl, bx), 69 SDT_NAME_REG(bh, bx), 70 SDT_NAME_REG(ecx, cx), 71 SDT_NAME_REG(rcx, cx), 72 SDT_NAME_REG(cl, cx), 73 SDT_NAME_REG(ch, cx), 74 SDT_NAME_REG(edx, dx), 75 SDT_NAME_REG(rdx, dx), 76 SDT_NAME_REG(dl, dx), 77 SDT_NAME_REG(dh, dx), 78 SDT_NAME_REG(esi, si), 79 SDT_NAME_REG(rsi, si), 80 SDT_NAME_REG(sil, si), 81 SDT_NAME_REG(edi, di), 82 SDT_NAME_REG(rdi, di), 83 SDT_NAME_REG(dil, di), 84 SDT_NAME_REG(ebp, bp), 85 SDT_NAME_REG(rbp, bp), 86 SDT_NAME_REG(bpl, bp), 87 SDT_NAME_REG(rsp, sp), 88 SDT_NAME_REG(esp, sp), 89 SDT_NAME_REG(spl, sp), 90 91 /* rNN registers */ 92 SDT_NAME_REG(r8b, r8), 93 SDT_NAME_REG(r8w, r8), 94 SDT_NAME_REG(r8d, r8), 95 SDT_NAME_REG(r9b, r9), 96 SDT_NAME_REG(r9w, r9), 97 SDT_NAME_REG(r9d, r9), 98 SDT_NAME_REG(r10b, r10), 99 SDT_NAME_REG(r10w, r10), 100 SDT_NAME_REG(r10d, r10), 101 SDT_NAME_REG(r11b, r11), 102 SDT_NAME_REG(r11w, r11), 103 SDT_NAME_REG(r11d, r11), 104 SDT_NAME_REG(r12b, r12), 105 SDT_NAME_REG(r12w, r12), 106 SDT_NAME_REG(r12d, r12), 107 SDT_NAME_REG(r13b, r13), 108 SDT_NAME_REG(r13w, r13), 109 SDT_NAME_REG(r13d, r13), 110 SDT_NAME_REG(r14b, r14), 111 SDT_NAME_REG(r14w, r14), 112 SDT_NAME_REG(r14d, r14), 113 SDT_NAME_REG(r15b, r15), 114 SDT_NAME_REG(r15w, r15), 115 SDT_NAME_REG(r15d, r15), 116 SDT_NAME_REG_END, 117 }; 118 119 /* 120 * Perf only supports OP which is in +/-NUM(REG) form. 121 * Here plus-minus sign, NUM and parenthesis are optional, 122 * only REG is mandatory. 123 * 124 * SDT events also supports indirect addressing mode with a 125 * symbol as offset, scaled mode and constants in OP. But 126 * perf does not support them yet. Below are few examples. 127 * 128 * OP with scaled mode: 129 * (%rax,%rsi,8) 130 * 10(%ras,%rsi,8) 131 * 132 * OP with indirect addressing mode: 133 * check_action(%rip) 134 * mp_+52(%rip) 135 * 44+mp_(%rip) 136 * 137 * OP with constant values: 138 * $0 139 * $123 140 * $-1 141 */ 142 #define SDT_OP_REGEX "^([+\\-]?)([0-9]*)(\\(?)(%[a-z][a-z0-9]+)(\\)?)$" 143 144 static regex_t sdt_op_regex; 145 146 static int sdt_init_op_regex(void) 147 { 148 static int initialized; 149 int ret = 0; 150 151 if (initialized) 152 return 0; 153 154 ret = regcomp(&sdt_op_regex, SDT_OP_REGEX, REG_EXTENDED); 155 if (ret < 0) { 156 pr_debug4("Regex compilation error.\n"); 157 return ret; 158 } 159 160 initialized = 1; 161 return 0; 162 } 163 164 /* 165 * Max x86 register name length is 5(ex: %r15d). So, 6th char 166 * should always contain NULL. This helps to find register name 167 * length using strlen, insted of maintaing one more variable. 168 */ 169 #define SDT_REG_NAME_SIZE 6 170 171 /* 172 * The uprobe parser does not support all gas register names; 173 * so, we have to replace them (ex. for x86_64: %rax -> %ax). 174 * Note: If register does not require renaming, just copy 175 * paste as it is, but don't leave it empty. 176 */ 177 static void sdt_rename_register(char *sdt_reg, int sdt_len, char *uprobe_reg) 178 { 179 int i = 0; 180 181 for (i = 0; sdt_reg_tbl[i].sdt_name != NULL; i++) { 182 if (!strncmp(sdt_reg_tbl[i].sdt_name, sdt_reg, sdt_len)) { 183 strcpy(uprobe_reg, sdt_reg_tbl[i].uprobe_name); 184 return; 185 } 186 } 187 188 strncpy(uprobe_reg, sdt_reg, sdt_len); 189 } 190 191 int arch_sdt_arg_parse_op(char *old_op, char **new_op) 192 { 193 char new_reg[SDT_REG_NAME_SIZE] = {0}; 194 int new_len = 0, ret; 195 /* 196 * rm[0]: +/-NUM(REG) 197 * rm[1]: +/- 198 * rm[2]: NUM 199 * rm[3]: ( 200 * rm[4]: REG 201 * rm[5]: ) 202 */ 203 regmatch_t rm[6]; 204 /* 205 * Max prefix length is 2 as it may contains sign(+/-) 206 * and displacement 0 (Both sign and displacement 0 are 207 * optional so it may be empty). Use one more character 208 * to hold last NULL so that strlen can be used to find 209 * prefix length, instead of maintaing one more variable. 210 */ 211 char prefix[3] = {0}; 212 213 ret = sdt_init_op_regex(); 214 if (ret < 0) 215 return ret; 216 217 /* 218 * If unsupported OR does not match with regex OR 219 * register name too long, skip it. 220 */ 221 if (strchr(old_op, ',') || strchr(old_op, '$') || 222 regexec(&sdt_op_regex, old_op, 6, rm, 0) || 223 rm[4].rm_eo - rm[4].rm_so > SDT_REG_NAME_SIZE) { 224 pr_debug4("Skipping unsupported SDT argument: %s\n", old_op); 225 return SDT_ARG_SKIP; 226 } 227 228 /* 229 * Prepare prefix. 230 * If SDT OP has parenthesis but does not provide 231 * displacement, add 0 for displacement. 232 * SDT Uprobe Prefix 233 * ----------------------------- 234 * +24(%rdi) +24(%di) + 235 * 24(%rdi) +24(%di) + 236 * %rdi %di 237 * (%rdi) +0(%di) +0 238 * -80(%rbx) -80(%bx) - 239 */ 240 if (rm[3].rm_so != rm[3].rm_eo) { 241 if (rm[1].rm_so != rm[1].rm_eo) 242 prefix[0] = *(old_op + rm[1].rm_so); 243 else if (rm[2].rm_so != rm[2].rm_eo) 244 prefix[0] = '+'; 245 else 246 scnprintf(prefix, sizeof(prefix), "+0"); 247 } 248 249 /* Rename register */ 250 sdt_rename_register(old_op + rm[4].rm_so, rm[4].rm_eo - rm[4].rm_so, 251 new_reg); 252 253 /* Prepare final OP which should be valid for uprobe_events */ 254 new_len = strlen(prefix) + 255 (rm[2].rm_eo - rm[2].rm_so) + 256 (rm[3].rm_eo - rm[3].rm_so) + 257 strlen(new_reg) + 258 (rm[5].rm_eo - rm[5].rm_so) + 259 1; /* NULL */ 260 261 *new_op = zalloc(new_len); 262 if (!*new_op) 263 return -ENOMEM; 264 265 scnprintf(*new_op, new_len, "%.*s%.*s%.*s%.*s%.*s", 266 strlen(prefix), prefix, 267 (int)(rm[2].rm_eo - rm[2].rm_so), old_op + rm[2].rm_so, 268 (int)(rm[3].rm_eo - rm[3].rm_so), old_op + rm[3].rm_so, 269 strlen(new_reg), new_reg, 270 (int)(rm[5].rm_eo - rm[5].rm_so), old_op + rm[5].rm_so); 271 272 return SDT_ARG_VALID; 273 } 274 275 uint64_t arch__intr_reg_mask(void) 276 { 277 struct perf_event_attr attr = { 278 .type = PERF_TYPE_HARDWARE, 279 .config = PERF_COUNT_HW_CPU_CYCLES, 280 .sample_type = PERF_SAMPLE_REGS_INTR, 281 .sample_regs_intr = PERF_REG_EXTENDED_MASK, 282 .precise_ip = 1, 283 .disabled = 1, 284 .exclude_kernel = 1, 285 }; 286 int fd; 287 /* 288 * In an unnamed union, init it here to build on older gcc versions 289 */ 290 attr.sample_period = 1; 291 292 event_attr_init(&attr); 293 294 fd = sys_perf_event_open(&attr, 0, -1, -1, 0); 295 if (fd != -1) { 296 close(fd); 297 return (PERF_REG_EXTENDED_MASK | PERF_REGS_MASK); 298 } 299 300 return PERF_REGS_MASK; 301 } 302