tools/perf/arch/arm64/util/perf_regs.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <errno.h>
   3 #include <regex.h>
   4 #include <string.h>
   5 #include <sys/auxv.h>
   6 #include <linux/kernel.h>
   7 #include <linux/zalloc.h>
   8
   9 #include "perf_regs.h"
  10 #include "../../../perf-sys.h"
  11 #include "../../../util/debug.h"
  12 #include "../../../util/event.h"
  13 #include "../../../util/perf_regs.h"
  14
  15 #ifndef HWCAP_SVE
  16 #define HWCAP_SVE       (1 << 22)
  17 #endif
  18
  19 const struct sample_reg sample_reg_masks[] = {
  20         SMPL_REG(x0, PERF_REG_ARM64_X0),
  21         SMPL_REG(x1, PERF_REG_ARM64_X1),
  22         SMPL_REG(x2, PERF_REG_ARM64_X2),
  23         SMPL_REG(x3, PERF_REG_ARM64_X3),
  24         SMPL_REG(x4, PERF_REG_ARM64_X4),
  25         SMPL_REG(x5, PERF_REG_ARM64_X5),
  26         SMPL_REG(x6, PERF_REG_ARM64_X6),
  27         SMPL_REG(x7, PERF_REG_ARM64_X7),
  28         SMPL_REG(x8, PERF_REG_ARM64_X8),
  29         SMPL_REG(x9, PERF_REG_ARM64_X9),
  30         SMPL_REG(x10, PERF_REG_ARM64_X10),
  31         SMPL_REG(x11, PERF_REG_ARM64_X11),
  32         SMPL_REG(x12, PERF_REG_ARM64_X12),
  33         SMPL_REG(x13, PERF_REG_ARM64_X13),
  34         SMPL_REG(x14, PERF_REG_ARM64_X14),
  35         SMPL_REG(x15, PERF_REG_ARM64_X15),
  36         SMPL_REG(x16, PERF_REG_ARM64_X16),
  37         SMPL_REG(x17, PERF_REG_ARM64_X17),
  38         SMPL_REG(x18, PERF_REG_ARM64_X18),
  39         SMPL_REG(x19, PERF_REG_ARM64_X19),
  40         SMPL_REG(x20, PERF_REG_ARM64_X20),
  41         SMPL_REG(x21, PERF_REG_ARM64_X21),
  42         SMPL_REG(x22, PERF_REG_ARM64_X22),
  43         SMPL_REG(x23, PERF_REG_ARM64_X23),
  44         SMPL_REG(x24, PERF_REG_ARM64_X24),
  45         SMPL_REG(x25, PERF_REG_ARM64_X25),
  46         SMPL_REG(x26, PERF_REG_ARM64_X26),
  47         SMPL_REG(x27, PERF_REG_ARM64_X27),
  48         SMPL_REG(x28, PERF_REG_ARM64_X28),
  49         SMPL_REG(x29, PERF_REG_ARM64_X29),
  50         SMPL_REG(lr, PERF_REG_ARM64_LR),
  51         SMPL_REG(sp, PERF_REG_ARM64_SP),
  52         SMPL_REG(pc, PERF_REG_ARM64_PC),
  53         SMPL_REG(vg, PERF_REG_ARM64_VG),
  54         SMPL_REG_END
  55 };
  56
  57 /* %xNUM */
  58 #define SDT_OP_REGEX1  "^(x[1-2]?[0-9]|3[0-1])$"
  59
  60 /* [sp], [sp, NUM] */
  61 #define SDT_OP_REGEX2  "^\\[sp(, )?([0-9]+)?\\]$"
  62
  63 static regex_t sdt_op_regex1, sdt_op_regex2;
  64
  65 static int sdt_init_op_regex(void)
  66 {
  67         static int initialized;
  68         int ret = 0;
  69
  70         if (initialized)
  71                 return 0;
  72
  73         ret = regcomp(&sdt_op_regex1, SDT_OP_REGEX1, REG_EXTENDED);
  74         if (ret)
  75                 goto error;
  76
  77         ret = regcomp(&sdt_op_regex2, SDT_OP_REGEX2, REG_EXTENDED);
  78         if (ret)
  79                 goto free_regex1;
  80
  81         initialized = 1;
  82         return 0;
  83
  84 free_regex1:
  85         regfree(&sdt_op_regex1);
  86 error:
  87         pr_debug4("Regex compilation error.\n");
  88         return ret;
  89 }
  90
  91 /*
  92  * SDT marker arguments on Arm64 uses %xREG or [sp, NUM], currently
  93  * support these two formats.
  94  */
  95 int arch_sdt_arg_parse_op(char *old_op, char **new_op)
  96 {
  97         int ret, new_len;
  98         regmatch_t rm[5];
  99
 100         ret = sdt_init_op_regex();
 101         if (ret < 0)
 102                 return ret;
 103
 104         if (!regexec(&sdt_op_regex1, old_op, 3, rm, 0)) {
 105                 /* Extract xNUM */
 106                 new_len = 2;    /* % NULL */
 107                 new_len += (int)(rm[1].rm_eo - rm[1].rm_so);
 108
 109                 *new_op = zalloc(new_len);
 110                 if (!*new_op)
 111                         return -ENOMEM;
 112
 113                 scnprintf(*new_op, new_len, "%%%.*s",
 114                         (int)(rm[1].rm_eo - rm[1].rm_so), old_op + rm[1].rm_so);
 115         } else if (!regexec(&sdt_op_regex2, old_op, 5, rm, 0)) {
 116                 /* [sp], [sp, NUM] or [sp,NUM] */
 117                 new_len = 7;    /* + ( % s p ) NULL */
 118
 119                 /* If the argument is [sp], need to fill offset '0' */
 120                 if (rm[2].rm_so == -1)
 121                         new_len += 1;
 122                 else
 123                         new_len += (int)(rm[2].rm_eo - rm[2].rm_so);
 124
 125                 *new_op = zalloc(new_len);
 126                 if (!*new_op)
 127                         return -ENOMEM;
 128
 129                 if (rm[2].rm_so == -1)
 130                         scnprintf(*new_op, new_len, "+0(%%sp)");
 131                 else
 132                         scnprintf(*new_op, new_len, "+%.*s(%%sp)",
 133                                   (int)(rm[2].rm_eo - rm[2].rm_so),
 134                                   old_op + rm[2].rm_so);
 135         } else {
 136                 pr_debug4("Skipping unsupported SDT argument: %s\n", old_op);
 137                 return SDT_ARG_SKIP;
 138         }
 139
 140         return SDT_ARG_VALID;
 141 }
 142
 143 uint64_t arch__intr_reg_mask(void)
 144 {
 145         return PERF_REGS_MASK;
 146 }
 147
 148 uint64_t arch__user_reg_mask(void)
 149 {
 150         struct perf_event_attr attr = {
 151                 .type                   = PERF_TYPE_HARDWARE,
 152                 .config                 = PERF_COUNT_HW_CPU_CYCLES,
 153                 .sample_type            = PERF_SAMPLE_REGS_USER,
 154                 .disabled               = 1,
 155                 .exclude_kernel         = 1,
 156                 .sample_period          = 1,
 157                 .sample_regs_user       = PERF_REGS_MASK
 158         };
 159         int fd;
 160
 161         if (getauxval(AT_HWCAP) & HWCAP_SVE)
 162                 attr.sample_regs_user |= SMPL_REG_MASK(PERF_REG_ARM64_VG);
 163
 164         /*
 165          * Check if the pmu supports perf extended regs, before
 166          * returning the register mask to sample.
 167          */
 168         if (attr.sample_regs_user != PERF_REGS_MASK) {
 169                 event_attr_init(&attr);
 170                 fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
 171                 if (fd != -1) {
 172                         close(fd);
 173                         return attr.sample_regs_user;
 174                 }
 175         }
 176         return PERF_REGS_MASK;
 177 }