xref: /linux/tools/perf/util/perf-regs-arch/perf_regs_aarch64.c (revision c7decec2f2d2ab0366567f9e30c0e1418cece43f)
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 "../debug.h"
10 #include "../event.h"
11 #include "../perf_regs.h"
12 #include "../../perf-sys.h"
13 #include "../../arch/arm64/include/perf_regs.h"
14 
15 #define SMPL_REG_MASK(b) (1ULL << (b))
16 
17 #ifndef HWCAP_SVE
18 #define HWCAP_SVE	(1 << 22)
19 #endif
20 
21 /* %xNUM */
22 #define SDT_OP_REGEX1  "^(x[1-2]?[0-9]|3[0-1])$"
23 
24 /* [sp], [sp, NUM] */
25 #define SDT_OP_REGEX2  "^\\[sp(, )?([0-9]+)?\\]$"
26 
27 static regex_t sdt_op_regex1, sdt_op_regex2;
28 
sdt_init_op_regex(void)29 static int sdt_init_op_regex(void)
30 {
31 	static int initialized;
32 	int ret = 0;
33 
34 	if (initialized)
35 		return 0;
36 
37 	ret = regcomp(&sdt_op_regex1, SDT_OP_REGEX1, REG_EXTENDED);
38 	if (ret)
39 		goto error;
40 
41 	ret = regcomp(&sdt_op_regex2, SDT_OP_REGEX2, REG_EXTENDED);
42 	if (ret)
43 		goto free_regex1;
44 
45 	initialized = 1;
46 	return 0;
47 
48 free_regex1:
49 	regfree(&sdt_op_regex1);
50 error:
51 	pr_debug4("Regex compilation error.\n");
52 	return ret;
53 }
54 
55 /*
56  * SDT marker arguments on Arm64 uses %xREG or [sp, NUM], currently
57  * support these two formats.
58  */
__perf_sdt_arg_parse_op_arm64(char * old_op,char ** new_op)59 int __perf_sdt_arg_parse_op_arm64(char *old_op, char **new_op)
60 {
61 	int ret, new_len;
62 	regmatch_t rm[5];
63 
64 	ret = sdt_init_op_regex();
65 	if (ret < 0)
66 		return ret;
67 
68 	if (!regexec(&sdt_op_regex1, old_op, 3, rm, 0)) {
69 		/* Extract xNUM */
70 		new_len = 2;	/* % NULL */
71 		new_len += (int)(rm[1].rm_eo - rm[1].rm_so);
72 
73 		*new_op = zalloc(new_len);
74 		if (!*new_op)
75 			return -ENOMEM;
76 
77 		scnprintf(*new_op, new_len, "%%%.*s",
78 			(int)(rm[1].rm_eo - rm[1].rm_so), old_op + rm[1].rm_so);
79 	} else if (!regexec(&sdt_op_regex2, old_op, 5, rm, 0)) {
80 		/* [sp], [sp, NUM] or [sp,NUM] */
81 		new_len = 7;	/* + ( % s p ) NULL */
82 
83 		/* If the argument is [sp], need to fill offset '0' */
84 		if (rm[2].rm_so == -1)
85 			new_len += 1;
86 		else
87 			new_len += (int)(rm[2].rm_eo - rm[2].rm_so);
88 
89 		*new_op = zalloc(new_len);
90 		if (!*new_op)
91 			return -ENOMEM;
92 
93 		if (rm[2].rm_so == -1)
94 			scnprintf(*new_op, new_len, "+0(%%sp)");
95 		else
96 			scnprintf(*new_op, new_len, "+%.*s(%%sp)",
97 				  (int)(rm[2].rm_eo - rm[2].rm_so),
98 				  old_op + rm[2].rm_so);
99 	} else {
100 		pr_debug4("Skipping unsupported SDT argument: %s\n", old_op);
101 		return SDT_ARG_SKIP;
102 	}
103 
104 	return SDT_ARG_VALID;
105 }
106 
__perf_reg_mask_arm64(bool intr)107 uint64_t __perf_reg_mask_arm64(bool intr)
108 {
109 	struct perf_event_attr attr = {
110 		.type                   = PERF_TYPE_HARDWARE,
111 		.config                 = PERF_COUNT_HW_CPU_CYCLES,
112 		.sample_type            = PERF_SAMPLE_REGS_USER,
113 		.disabled               = 1,
114 		.exclude_kernel         = 1,
115 		.sample_period		= 1,
116 		.sample_regs_user	= PERF_REGS_MASK
117 	};
118 	int fd;
119 
120 	if (intr)
121 		return PERF_REGS_MASK;
122 
123 	if (getauxval(AT_HWCAP) & HWCAP_SVE)
124 		attr.sample_regs_user |= SMPL_REG_MASK(PERF_REG_ARM64_VG);
125 
126 	/*
127 	 * Check if the pmu supports perf extended regs, before
128 	 * returning the register mask to sample. Open the event
129 	 * on the perf process to check this.
130 	 */
131 	if (attr.sample_regs_user != PERF_REGS_MASK) {
132 		event_attr_init(&attr);
133 		fd = sys_perf_event_open(&attr, /*pid=*/0, /*cpu=*/-1,
134 					 /*group_fd=*/-1, /*flags=*/0);
135 		if (fd != -1) {
136 			close(fd);
137 			return attr.sample_regs_user;
138 		}
139 	}
140 	return PERF_REGS_MASK;
141 }
142 
__perf_reg_name_arm64(int id)143 const char *__perf_reg_name_arm64(int id)
144 {
145 	switch (id) {
146 	case PERF_REG_ARM64_X0:
147 		return "x0";
148 	case PERF_REG_ARM64_X1:
149 		return "x1";
150 	case PERF_REG_ARM64_X2:
151 		return "x2";
152 	case PERF_REG_ARM64_X3:
153 		return "x3";
154 	case PERF_REG_ARM64_X4:
155 		return "x4";
156 	case PERF_REG_ARM64_X5:
157 		return "x5";
158 	case PERF_REG_ARM64_X6:
159 		return "x6";
160 	case PERF_REG_ARM64_X7:
161 		return "x7";
162 	case PERF_REG_ARM64_X8:
163 		return "x8";
164 	case PERF_REG_ARM64_X9:
165 		return "x9";
166 	case PERF_REG_ARM64_X10:
167 		return "x10";
168 	case PERF_REG_ARM64_X11:
169 		return "x11";
170 	case PERF_REG_ARM64_X12:
171 		return "x12";
172 	case PERF_REG_ARM64_X13:
173 		return "x13";
174 	case PERF_REG_ARM64_X14:
175 		return "x14";
176 	case PERF_REG_ARM64_X15:
177 		return "x15";
178 	case PERF_REG_ARM64_X16:
179 		return "x16";
180 	case PERF_REG_ARM64_X17:
181 		return "x17";
182 	case PERF_REG_ARM64_X18:
183 		return "x18";
184 	case PERF_REG_ARM64_X19:
185 		return "x19";
186 	case PERF_REG_ARM64_X20:
187 		return "x20";
188 	case PERF_REG_ARM64_X21:
189 		return "x21";
190 	case PERF_REG_ARM64_X22:
191 		return "x22";
192 	case PERF_REG_ARM64_X23:
193 		return "x23";
194 	case PERF_REG_ARM64_X24:
195 		return "x24";
196 	case PERF_REG_ARM64_X25:
197 		return "x25";
198 	case PERF_REG_ARM64_X26:
199 		return "x26";
200 	case PERF_REG_ARM64_X27:
201 		return "x27";
202 	case PERF_REG_ARM64_X28:
203 		return "x28";
204 	case PERF_REG_ARM64_X29:
205 		return "x29";
206 	case PERF_REG_ARM64_SP:
207 		return "sp";
208 	case PERF_REG_ARM64_LR:
209 		return "lr";
210 	case PERF_REG_ARM64_PC:
211 		return "pc";
212 	case PERF_REG_ARM64_VG:
213 		return "vg";
214 	default:
215 		return NULL;
216 	}
217 
218 	return NULL;
219 }
220 
__perf_reg_ip_arm64(void)221 uint64_t __perf_reg_ip_arm64(void)
222 {
223 	return PERF_REG_ARM64_PC;
224 }
225 
__perf_reg_sp_arm64(void)226 uint64_t __perf_reg_sp_arm64(void)
227 {
228 	return PERF_REG_ARM64_SP;
229 }
230