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