xref: /linux/tools/perf/util/debug.c (revision 17cfcb68af3bc7d5e8ae08779b1853310a2949f3)
1 // SPDX-License-Identifier: GPL-2.0
2 /* For general debugging purposes */
3 
4 #include <inttypes.h>
5 #include <string.h>
6 #include <stdarg.h>
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <sys/wait.h>
10 #include <api/debug.h>
11 #include <linux/kernel.h>
12 #include <linux/time64.h>
13 #ifdef HAVE_BACKTRACE_SUPPORT
14 #include <execinfo.h>
15 #endif
16 #include "color.h"
17 #include "event.h"
18 #include "debug.h"
19 #include "print_binary.h"
20 #include "target.h"
21 #include "ui/helpline.h"
22 #include "ui/ui.h"
23 
24 #include <linux/ctype.h>
25 
26 int verbose;
27 bool dump_trace = false, quiet = false;
28 int debug_ordered_events;
29 static int redirect_to_stderr;
30 int debug_data_convert;
31 
32 int veprintf(int level, int var, const char *fmt, va_list args)
33 {
34 	int ret = 0;
35 
36 	if (var >= level) {
37 		if (use_browser >= 1 && !redirect_to_stderr)
38 			ui_helpline__vshow(fmt, args);
39 		else
40 			ret = vfprintf(stderr, fmt, args);
41 	}
42 
43 	return ret;
44 }
45 
46 int eprintf(int level, int var, const char *fmt, ...)
47 {
48 	va_list args;
49 	int ret;
50 
51 	va_start(args, fmt);
52 	ret = veprintf(level, var, fmt, args);
53 	va_end(args);
54 
55 	return ret;
56 }
57 
58 static int veprintf_time(u64 t, const char *fmt, va_list args)
59 {
60 	int ret = 0;
61 	u64 secs, usecs, nsecs = t;
62 
63 	secs   = nsecs / NSEC_PER_SEC;
64 	nsecs -= secs  * NSEC_PER_SEC;
65 	usecs  = nsecs / NSEC_PER_USEC;
66 
67 	ret = fprintf(stderr, "[%13" PRIu64 ".%06" PRIu64 "] ",
68 		      secs, usecs);
69 	ret += vfprintf(stderr, fmt, args);
70 	return ret;
71 }
72 
73 int eprintf_time(int level, int var, u64 t, const char *fmt, ...)
74 {
75 	int ret = 0;
76 	va_list args;
77 
78 	if (var >= level) {
79 		va_start(args, fmt);
80 		ret = veprintf_time(t, fmt, args);
81 		va_end(args);
82 	}
83 
84 	return ret;
85 }
86 
87 /*
88  * Overloading libtraceevent standard info print
89  * function, display with -v in perf.
90  */
91 void pr_stat(const char *fmt, ...)
92 {
93 	va_list args;
94 
95 	va_start(args, fmt);
96 	veprintf(1, verbose, fmt, args);
97 	va_end(args);
98 	eprintf(1, verbose, "\n");
99 }
100 
101 int dump_printf(const char *fmt, ...)
102 {
103 	va_list args;
104 	int ret = 0;
105 
106 	if (dump_trace) {
107 		va_start(args, fmt);
108 		ret = vprintf(fmt, args);
109 		va_end(args);
110 	}
111 
112 	return ret;
113 }
114 
115 static int trace_event_printer(enum binary_printer_ops op,
116 			       unsigned int val, void *extra, FILE *fp)
117 {
118 	const char *color = PERF_COLOR_BLUE;
119 	union perf_event *event = (union perf_event *)extra;
120 	unsigned char ch = (unsigned char)val;
121 	int printed = 0;
122 
123 	switch (op) {
124 	case BINARY_PRINT_DATA_BEGIN:
125 		printed += fprintf(fp, ".");
126 		printed += color_fprintf(fp, color, "\n. ... raw event: size %d bytes\n",
127 					 event->header.size);
128 		break;
129 	case BINARY_PRINT_LINE_BEGIN:
130 		printed += fprintf(fp, ".");
131 		break;
132 	case BINARY_PRINT_ADDR:
133 		printed += color_fprintf(fp, color, "  %04x: ", val);
134 		break;
135 	case BINARY_PRINT_NUM_DATA:
136 		printed += color_fprintf(fp, color, " %02x", val);
137 		break;
138 	case BINARY_PRINT_NUM_PAD:
139 		printed += color_fprintf(fp, color, "   ");
140 		break;
141 	case BINARY_PRINT_SEP:
142 		printed += color_fprintf(fp, color, "  ");
143 		break;
144 	case BINARY_PRINT_CHAR_DATA:
145 		printed += color_fprintf(fp, color, "%c",
146 			      isprint(ch) ? ch : '.');
147 		break;
148 	case BINARY_PRINT_CHAR_PAD:
149 		printed += color_fprintf(fp, color, " ");
150 		break;
151 	case BINARY_PRINT_LINE_END:
152 		printed += color_fprintf(fp, color, "\n");
153 		break;
154 	case BINARY_PRINT_DATA_END:
155 		printed += fprintf(fp, "\n");
156 		break;
157 	default:
158 		break;
159 	}
160 
161 	return printed;
162 }
163 
164 void trace_event(union perf_event *event)
165 {
166 	unsigned char *raw_event = (void *)event;
167 
168 	if (!dump_trace)
169 		return;
170 
171 	print_binary(raw_event, event->header.size, 16,
172 		     trace_event_printer, event);
173 }
174 
175 static struct debug_variable {
176 	const char *name;
177 	int *ptr;
178 } debug_variables[] = {
179 	{ .name = "verbose",		.ptr = &verbose },
180 	{ .name = "ordered-events",	.ptr = &debug_ordered_events},
181 	{ .name = "stderr",		.ptr = &redirect_to_stderr},
182 	{ .name = "data-convert",	.ptr = &debug_data_convert },
183 	{ .name = NULL, }
184 };
185 
186 int perf_debug_option(const char *str)
187 {
188 	struct debug_variable *var = &debug_variables[0];
189 	char *vstr, *s = strdup(str);
190 	int v = 1;
191 
192 	vstr = strchr(s, '=');
193 	if (vstr)
194 		*vstr++ = 0;
195 
196 	while (var->name) {
197 		if (!strcmp(s, var->name))
198 			break;
199 		var++;
200 	}
201 
202 	if (!var->name) {
203 		pr_err("Unknown debug variable name '%s'\n", s);
204 		free(s);
205 		return -1;
206 	}
207 
208 	if (vstr) {
209 		v = atoi(vstr);
210 		/*
211 		 * Allow only values in range (0, 10),
212 		 * otherwise set 0.
213 		 */
214 		v = (v < 0) || (v > 10) ? 0 : v;
215 	}
216 
217 	if (quiet)
218 		v = -1;
219 
220 	*var->ptr = v;
221 	free(s);
222 	return 0;
223 }
224 
225 int perf_quiet_option(void)
226 {
227 	struct debug_variable *var = &debug_variables[0];
228 
229 	/* disable all debug messages */
230 	while (var->name) {
231 		*var->ptr = -1;
232 		var++;
233 	}
234 
235 	return 0;
236 }
237 
238 #define DEBUG_WRAPPER(__n, __l)				\
239 static int pr_ ## __n ## _wrapper(const char *fmt, ...)	\
240 {							\
241 	va_list args;					\
242 	int ret;					\
243 							\
244 	va_start(args, fmt);				\
245 	ret = veprintf(__l, verbose, fmt, args);	\
246 	va_end(args);					\
247 	return ret;					\
248 }
249 
250 DEBUG_WRAPPER(warning, 0);
251 DEBUG_WRAPPER(debug, 1);
252 
253 void perf_debug_setup(void)
254 {
255 	libapi_set_print(pr_warning_wrapper, pr_warning_wrapper, pr_debug_wrapper);
256 }
257 
258 /* Obtain a backtrace and print it to stdout. */
259 #ifdef HAVE_BACKTRACE_SUPPORT
260 void dump_stack(void)
261 {
262 	void *array[16];
263 	size_t size = backtrace(array, ARRAY_SIZE(array));
264 	char **strings = backtrace_symbols(array, size);
265 	size_t i;
266 
267 	printf("Obtained %zd stack frames.\n", size);
268 
269 	for (i = 0; i < size; i++)
270 		printf("%s\n", strings[i]);
271 
272 	free(strings);
273 }
274 #else
275 void dump_stack(void) {}
276 #endif
277 
278 void sighandler_dump_stack(int sig)
279 {
280 	psignal(sig, "perf");
281 	dump_stack();
282 	signal(sig, SIG_DFL);
283 	raise(sig);
284 }
285