xref: /linux/tools/perf/util/debug.c (revision 088e88be5a380cc4e81963a9a02815da465d144f)
1 // SPDX-License-Identifier: GPL-2.0
2 /* For general debugging purposes */
3 
4 #include "../perf.h"
5 
6 #include <inttypes.h>
7 #include <string.h>
8 #include <stdarg.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <sys/wait.h>
12 #include <api/debug.h>
13 #include <linux/time64.h>
14 #ifdef HAVE_BACKTRACE_SUPPORT
15 #include <execinfo.h>
16 #endif
17 #include "cache.h"
18 #include "color.h"
19 #include "event.h"
20 #include "debug.h"
21 #include "print_binary.h"
22 #include "util.h"
23 #include "target.h"
24 
25 #include <linux/ctype.h>
26 
27 int verbose;
28 bool dump_trace = false, quiet = false;
29 int debug_ordered_events;
30 static int redirect_to_stderr;
31 int debug_data_convert;
32 
33 int veprintf(int level, int var, const char *fmt, va_list args)
34 {
35 	int ret = 0;
36 
37 	if (var >= level) {
38 		if (use_browser >= 1 && !redirect_to_stderr)
39 			ui_helpline__vshow(fmt, args);
40 		else
41 			ret = vfprintf(stderr, fmt, args);
42 	}
43 
44 	return ret;
45 }
46 
47 int eprintf(int level, int var, const char *fmt, ...)
48 {
49 	va_list args;
50 	int ret;
51 
52 	va_start(args, fmt);
53 	ret = veprintf(level, var, fmt, args);
54 	va_end(args);
55 
56 	return ret;
57 }
58 
59 static int veprintf_time(u64 t, const char *fmt, va_list args)
60 {
61 	int ret = 0;
62 	u64 secs, usecs, nsecs = t;
63 
64 	secs   = nsecs / NSEC_PER_SEC;
65 	nsecs -= secs  * NSEC_PER_SEC;
66 	usecs  = nsecs / NSEC_PER_USEC;
67 
68 	ret = fprintf(stderr, "[%13" PRIu64 ".%06" PRIu64 "] ",
69 		      secs, usecs);
70 	ret += vfprintf(stderr, fmt, args);
71 	return ret;
72 }
73 
74 int eprintf_time(int level, int var, u64 t, const char *fmt, ...)
75 {
76 	int ret = 0;
77 	va_list args;
78 
79 	if (var >= level) {
80 		va_start(args, fmt);
81 		ret = veprintf_time(t, fmt, args);
82 		va_end(args);
83 	}
84 
85 	return ret;
86 }
87 
88 /*
89  * Overloading libtraceevent standard info print
90  * function, display with -v in perf.
91  */
92 void pr_stat(const char *fmt, ...)
93 {
94 	va_list args;
95 
96 	va_start(args, fmt);
97 	veprintf(1, verbose, fmt, args);
98 	va_end(args);
99 	eprintf(1, verbose, "\n");
100 }
101 
102 int dump_printf(const char *fmt, ...)
103 {
104 	va_list args;
105 	int ret = 0;
106 
107 	if (dump_trace) {
108 		va_start(args, fmt);
109 		ret = vprintf(fmt, args);
110 		va_end(args);
111 	}
112 
113 	return ret;
114 }
115 
116 static int trace_event_printer(enum binary_printer_ops op,
117 			       unsigned int val, void *extra, FILE *fp)
118 {
119 	const char *color = PERF_COLOR_BLUE;
120 	union perf_event *event = (union perf_event *)extra;
121 	unsigned char ch = (unsigned char)val;
122 	int printed = 0;
123 
124 	switch (op) {
125 	case BINARY_PRINT_DATA_BEGIN:
126 		printed += fprintf(fp, ".");
127 		printed += color_fprintf(fp, color, "\n. ... raw event: size %d bytes\n",
128 					 event->header.size);
129 		break;
130 	case BINARY_PRINT_LINE_BEGIN:
131 		printed += fprintf(fp, ".");
132 		break;
133 	case BINARY_PRINT_ADDR:
134 		printed += color_fprintf(fp, color, "  %04x: ", val);
135 		break;
136 	case BINARY_PRINT_NUM_DATA:
137 		printed += color_fprintf(fp, color, " %02x", val);
138 		break;
139 	case BINARY_PRINT_NUM_PAD:
140 		printed += color_fprintf(fp, color, "   ");
141 		break;
142 	case BINARY_PRINT_SEP:
143 		printed += color_fprintf(fp, color, "  ");
144 		break;
145 	case BINARY_PRINT_CHAR_DATA:
146 		printed += color_fprintf(fp, color, "%c",
147 			      isprint(ch) ? ch : '.');
148 		break;
149 	case BINARY_PRINT_CHAR_PAD:
150 		printed += color_fprintf(fp, color, " ");
151 		break;
152 	case BINARY_PRINT_LINE_END:
153 		printed += color_fprintf(fp, color, "\n");
154 		break;
155 	case BINARY_PRINT_DATA_END:
156 		printed += fprintf(fp, "\n");
157 		break;
158 	default:
159 		break;
160 	}
161 
162 	return printed;
163 }
164 
165 void trace_event(union perf_event *event)
166 {
167 	unsigned char *raw_event = (void *)event;
168 
169 	if (!dump_trace)
170 		return;
171 
172 	print_binary(raw_event, event->header.size, 16,
173 		     trace_event_printer, event);
174 }
175 
176 static struct debug_variable {
177 	const char *name;
178 	int *ptr;
179 } debug_variables[] = {
180 	{ .name = "verbose",		.ptr = &verbose },
181 	{ .name = "ordered-events",	.ptr = &debug_ordered_events},
182 	{ .name = "stderr",		.ptr = &redirect_to_stderr},
183 	{ .name = "data-convert",	.ptr = &debug_data_convert },
184 	{ .name = NULL, }
185 };
186 
187 int perf_debug_option(const char *str)
188 {
189 	struct debug_variable *var = &debug_variables[0];
190 	char *vstr, *s = strdup(str);
191 	int v = 1;
192 
193 	vstr = strchr(s, '=');
194 	if (vstr)
195 		*vstr++ = 0;
196 
197 	while (var->name) {
198 		if (!strcmp(s, var->name))
199 			break;
200 		var++;
201 	}
202 
203 	if (!var->name) {
204 		pr_err("Unknown debug variable name '%s'\n", s);
205 		free(s);
206 		return -1;
207 	}
208 
209 	if (vstr) {
210 		v = atoi(vstr);
211 		/*
212 		 * Allow only values in range (0, 10),
213 		 * otherwise set 0.
214 		 */
215 		v = (v < 0) || (v > 10) ? 0 : v;
216 	}
217 
218 	if (quiet)
219 		v = -1;
220 
221 	*var->ptr = v;
222 	free(s);
223 	return 0;
224 }
225 
226 int perf_quiet_option(void)
227 {
228 	struct debug_variable *var = &debug_variables[0];
229 
230 	/* disable all debug messages */
231 	while (var->name) {
232 		*var->ptr = -1;
233 		var++;
234 	}
235 
236 	return 0;
237 }
238 
239 #define DEBUG_WRAPPER(__n, __l)				\
240 static int pr_ ## __n ## _wrapper(const char *fmt, ...)	\
241 {							\
242 	va_list args;					\
243 	int ret;					\
244 							\
245 	va_start(args, fmt);				\
246 	ret = veprintf(__l, verbose, fmt, args);	\
247 	va_end(args);					\
248 	return ret;					\
249 }
250 
251 DEBUG_WRAPPER(warning, 0);
252 DEBUG_WRAPPER(debug, 1);
253 
254 void perf_debug_setup(void)
255 {
256 	libapi_set_print(pr_warning_wrapper, pr_warning_wrapper, pr_debug_wrapper);
257 }
258 
259 /* Obtain a backtrace and print it to stdout. */
260 #ifdef HAVE_BACKTRACE_SUPPORT
261 void dump_stack(void)
262 {
263 	void *array[16];
264 	size_t size = backtrace(array, ARRAY_SIZE(array));
265 	char **strings = backtrace_symbols(array, size);
266 	size_t i;
267 
268 	printf("Obtained %zd stack frames.\n", size);
269 
270 	for (i = 0; i < size; i++)
271 		printf("%s\n", strings[i]);
272 
273 	free(strings);
274 }
275 #else
276 void dump_stack(void) {}
277 #endif
278 
279 void sighandler_dump_stack(int sig)
280 {
281 	psignal(sig, "perf");
282 	dump_stack();
283 	signal(sig, SIG_DFL);
284 	raise(sig);
285 }
286