1 // SPDX-License-Identifier: GPL-2.0 2 #include <errno.h> 3 #include <string.h> 4 #include <regex.h> 5 #include <linux/kernel.h> 6 #include <linux/zalloc.h> 7 8 #include "../../../perf-sys.h" 9 #include "../../../util/perf_regs.h" 10 #include "../../../util/debug.h" 11 #include "../../../util/event.h" 12 #include "../../../util/pmu.h" 13 #include "../../../util/pmus.h" 14 15 const struct sample_reg sample_reg_masks[] = { 16 SMPL_REG(AX, PERF_REG_X86_AX), 17 SMPL_REG(BX, PERF_REG_X86_BX), 18 SMPL_REG(CX, PERF_REG_X86_CX), 19 SMPL_REG(DX, PERF_REG_X86_DX), 20 SMPL_REG(SI, PERF_REG_X86_SI), 21 SMPL_REG(DI, PERF_REG_X86_DI), 22 SMPL_REG(BP, PERF_REG_X86_BP), 23 SMPL_REG(SP, PERF_REG_X86_SP), 24 SMPL_REG(IP, PERF_REG_X86_IP), 25 SMPL_REG(FLAGS, PERF_REG_X86_FLAGS), 26 SMPL_REG(CS, PERF_REG_X86_CS), 27 SMPL_REG(SS, PERF_REG_X86_SS), 28 #ifdef HAVE_ARCH_X86_64_SUPPORT 29 SMPL_REG(R8, PERF_REG_X86_R8), 30 SMPL_REG(R9, PERF_REG_X86_R9), 31 SMPL_REG(R10, PERF_REG_X86_R10), 32 SMPL_REG(R11, PERF_REG_X86_R11), 33 SMPL_REG(R12, PERF_REG_X86_R12), 34 SMPL_REG(R13, PERF_REG_X86_R13), 35 SMPL_REG(R14, PERF_REG_X86_R14), 36 SMPL_REG(R15, PERF_REG_X86_R15), 37 #endif 38 SMPL_REG2(XMM0, PERF_REG_X86_XMM0), 39 SMPL_REG2(XMM1, PERF_REG_X86_XMM1), 40 SMPL_REG2(XMM2, PERF_REG_X86_XMM2), 41 SMPL_REG2(XMM3, PERF_REG_X86_XMM3), 42 SMPL_REG2(XMM4, PERF_REG_X86_XMM4), 43 SMPL_REG2(XMM5, PERF_REG_X86_XMM5), 44 SMPL_REG2(XMM6, PERF_REG_X86_XMM6), 45 SMPL_REG2(XMM7, PERF_REG_X86_XMM7), 46 SMPL_REG2(XMM8, PERF_REG_X86_XMM8), 47 SMPL_REG2(XMM9, PERF_REG_X86_XMM9), 48 SMPL_REG2(XMM10, PERF_REG_X86_XMM10), 49 SMPL_REG2(XMM11, PERF_REG_X86_XMM11), 50 SMPL_REG2(XMM12, PERF_REG_X86_XMM12), 51 SMPL_REG2(XMM13, PERF_REG_X86_XMM13), 52 SMPL_REG2(XMM14, PERF_REG_X86_XMM14), 53 SMPL_REG2(XMM15, PERF_REG_X86_XMM15), 54 SMPL_REG_END 55 }; 56 57 struct sdt_name_reg { 58 const char *sdt_name; 59 const char *uprobe_name; 60 }; 61 #define SDT_NAME_REG(n, m) {.sdt_name = "%" #n, .uprobe_name = "%" #m} 62 #define SDT_NAME_REG_END {.sdt_name = NULL, .uprobe_name = NULL} 63 64 static const struct sdt_name_reg sdt_reg_tbl[] = { 65 SDT_NAME_REG(eax, ax), 66 SDT_NAME_REG(rax, ax), 67 SDT_NAME_REG(al, ax), 68 SDT_NAME_REG(ah, ax), 69 SDT_NAME_REG(ebx, bx), 70 SDT_NAME_REG(rbx, bx), 71 SDT_NAME_REG(bl, bx), 72 SDT_NAME_REG(bh, bx), 73 SDT_NAME_REG(ecx, cx), 74 SDT_NAME_REG(rcx, cx), 75 SDT_NAME_REG(cl, cx), 76 SDT_NAME_REG(ch, cx), 77 SDT_NAME_REG(edx, dx), 78 SDT_NAME_REG(rdx, dx), 79 SDT_NAME_REG(dl, dx), 80 SDT_NAME_REG(dh, dx), 81 SDT_NAME_REG(esi, si), 82 SDT_NAME_REG(rsi, si), 83 SDT_NAME_REG(sil, si), 84 SDT_NAME_REG(edi, di), 85 SDT_NAME_REG(rdi, di), 86 SDT_NAME_REG(dil, di), 87 SDT_NAME_REG(ebp, bp), 88 SDT_NAME_REG(rbp, bp), 89 SDT_NAME_REG(bpl, bp), 90 SDT_NAME_REG(rsp, sp), 91 SDT_NAME_REG(esp, sp), 92 SDT_NAME_REG(spl, sp), 93 94 /* rNN registers */ 95 SDT_NAME_REG(r8b, r8), 96 SDT_NAME_REG(r8w, r8), 97 SDT_NAME_REG(r8d, r8), 98 SDT_NAME_REG(r9b, r9), 99 SDT_NAME_REG(r9w, r9), 100 SDT_NAME_REG(r9d, r9), 101 SDT_NAME_REG(r10b, r10), 102 SDT_NAME_REG(r10w, r10), 103 SDT_NAME_REG(r10d, r10), 104 SDT_NAME_REG(r11b, r11), 105 SDT_NAME_REG(r11w, r11), 106 SDT_NAME_REG(r11d, r11), 107 SDT_NAME_REG(r12b, r12), 108 SDT_NAME_REG(r12w, r12), 109 SDT_NAME_REG(r12d, r12), 110 SDT_NAME_REG(r13b, r13), 111 SDT_NAME_REG(r13w, r13), 112 SDT_NAME_REG(r13d, r13), 113 SDT_NAME_REG(r14b, r14), 114 SDT_NAME_REG(r14w, r14), 115 SDT_NAME_REG(r14d, r14), 116 SDT_NAME_REG(r15b, r15), 117 SDT_NAME_REG(r15w, r15), 118 SDT_NAME_REG(r15d, r15), 119 SDT_NAME_REG_END, 120 }; 121 122 /* 123 * Perf only supports OP which is in +/-NUM(REG) form. 124 * Here plus-minus sign, NUM and parenthesis are optional, 125 * only REG is mandatory. 126 * 127 * SDT events also supports indirect addressing mode with a 128 * symbol as offset, scaled mode and constants in OP. But 129 * perf does not support them yet. Below are few examples. 130 * 131 * OP with scaled mode: 132 * (%rax,%rsi,8) 133 * 10(%ras,%rsi,8) 134 * 135 * OP with indirect addressing mode: 136 * check_action(%rip) 137 * mp_+52(%rip) 138 * 44+mp_(%rip) 139 * 140 * OP with constant values: 141 * $0 142 * $123 143 * $-1 144 */ 145 #define SDT_OP_REGEX "^([+\\-]?)([0-9]*)(\\(?)(%[a-z][a-z0-9]+)(\\)?)$" 146 147 static regex_t sdt_op_regex; 148 149 static int sdt_init_op_regex(void) 150 { 151 static int initialized; 152 int ret = 0; 153 154 if (initialized) 155 return 0; 156 157 ret = regcomp(&sdt_op_regex, SDT_OP_REGEX, REG_EXTENDED); 158 if (ret < 0) { 159 pr_debug4("Regex compilation error.\n"); 160 return ret; 161 } 162 163 initialized = 1; 164 return 0; 165 } 166 167 /* 168 * Max x86 register name length is 5(ex: %r15d). So, 6th char 169 * should always contain NULL. This helps to find register name 170 * length using strlen, instead of maintaining one more variable. 171 */ 172 #define SDT_REG_NAME_SIZE 6 173 174 /* 175 * The uprobe parser does not support all gas register names; 176 * so, we have to replace them (ex. for x86_64: %rax -> %ax). 177 * Note: If register does not require renaming, just copy 178 * paste as it is, but don't leave it empty. 179 */ 180 static void sdt_rename_register(char *sdt_reg, int sdt_len, char *uprobe_reg) 181 { 182 int i = 0; 183 184 for (i = 0; sdt_reg_tbl[i].sdt_name != NULL; i++) { 185 if (!strncmp(sdt_reg_tbl[i].sdt_name, sdt_reg, sdt_len)) { 186 strcpy(uprobe_reg, sdt_reg_tbl[i].uprobe_name); 187 return; 188 } 189 } 190 191 strncpy(uprobe_reg, sdt_reg, sdt_len); 192 } 193 194 int arch_sdt_arg_parse_op(char *old_op, char **new_op) 195 { 196 char new_reg[SDT_REG_NAME_SIZE] = {0}; 197 int new_len = 0, ret; 198 /* 199 * rm[0]: +/-NUM(REG) 200 * rm[1]: +/- 201 * rm[2]: NUM 202 * rm[3]: ( 203 * rm[4]: REG 204 * rm[5]: ) 205 */ 206 regmatch_t rm[6]; 207 /* 208 * Max prefix length is 2 as it may contains sign(+/-) 209 * and displacement 0 (Both sign and displacement 0 are 210 * optional so it may be empty). Use one more character 211 * to hold last NULL so that strlen can be used to find 212 * prefix length, instead of maintaining one more variable. 213 */ 214 char prefix[3] = {0}; 215 216 ret = sdt_init_op_regex(); 217 if (ret < 0) 218 return ret; 219 220 /* 221 * If unsupported OR does not match with regex OR 222 * register name too long, skip it. 223 */ 224 if (strchr(old_op, ',') || strchr(old_op, '$') || 225 regexec(&sdt_op_regex, old_op, 6, rm, 0) || 226 rm[4].rm_eo - rm[4].rm_so > SDT_REG_NAME_SIZE) { 227 pr_debug4("Skipping unsupported SDT argument: %s\n", old_op); 228 return SDT_ARG_SKIP; 229 } 230 231 /* 232 * Prepare prefix. 233 * If SDT OP has parenthesis but does not provide 234 * displacement, add 0 for displacement. 235 * SDT Uprobe Prefix 236 * ----------------------------- 237 * +24(%rdi) +24(%di) + 238 * 24(%rdi) +24(%di) + 239 * %rdi %di 240 * (%rdi) +0(%di) +0 241 * -80(%rbx) -80(%bx) - 242 */ 243 if (rm[3].rm_so != rm[3].rm_eo) { 244 if (rm[1].rm_so != rm[1].rm_eo) 245 prefix[0] = *(old_op + rm[1].rm_so); 246 else if (rm[2].rm_so != rm[2].rm_eo) 247 prefix[0] = '+'; 248 else 249 scnprintf(prefix, sizeof(prefix), "+0"); 250 } 251 252 /* Rename register */ 253 sdt_rename_register(old_op + rm[4].rm_so, rm[4].rm_eo - rm[4].rm_so, 254 new_reg); 255 256 /* Prepare final OP which should be valid for uprobe_events */ 257 new_len = strlen(prefix) + 258 (rm[2].rm_eo - rm[2].rm_so) + 259 (rm[3].rm_eo - rm[3].rm_so) + 260 strlen(new_reg) + 261 (rm[5].rm_eo - rm[5].rm_so) + 262 1; /* NULL */ 263 264 *new_op = zalloc(new_len); 265 if (!*new_op) 266 return -ENOMEM; 267 268 scnprintf(*new_op, new_len, "%.*s%.*s%.*s%.*s%.*s", 269 strlen(prefix), prefix, 270 (int)(rm[2].rm_eo - rm[2].rm_so), old_op + rm[2].rm_so, 271 (int)(rm[3].rm_eo - rm[3].rm_so), old_op + rm[3].rm_so, 272 strlen(new_reg), new_reg, 273 (int)(rm[5].rm_eo - rm[5].rm_so), old_op + rm[5].rm_so); 274 275 return SDT_ARG_VALID; 276 } 277 278 uint64_t arch__intr_reg_mask(void) 279 { 280 struct perf_event_attr attr = { 281 .type = PERF_TYPE_HARDWARE, 282 .config = PERF_COUNT_HW_CPU_CYCLES, 283 .sample_type = PERF_SAMPLE_REGS_INTR, 284 .sample_regs_intr = PERF_REG_EXTENDED_MASK, 285 .precise_ip = 1, 286 .disabled = 1, 287 .exclude_kernel = 1, 288 }; 289 int fd; 290 /* 291 * In an unnamed union, init it here to build on older gcc versions 292 */ 293 attr.sample_period = 1; 294 295 if (perf_pmus__num_core_pmus() > 1) { 296 struct perf_pmu *pmu = NULL; 297 __u64 type = PERF_TYPE_RAW; 298 299 /* 300 * The same register set is supported among different hybrid PMUs. 301 * Only check the first available one. 302 */ 303 while ((pmu = perf_pmus__scan_core(pmu)) != NULL) { 304 type = pmu->type; 305 break; 306 } 307 attr.config |= type << PERF_PMU_TYPE_SHIFT; 308 } 309 310 event_attr_init(&attr); 311 312 fd = sys_perf_event_open(&attr, 0, -1, -1, 0); 313 if (fd != -1) { 314 close(fd); 315 return (PERF_REG_EXTENDED_MASK | PERF_REGS_MASK); 316 } 317 318 return PERF_REGS_MASK; 319 } 320