1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2012 The Chromium OS Authors.
4 */
5
6 #include <common.h>
7 #include <mapmem.h>
8 #include <trace.h>
9 #include <asm/io.h>
10 #include <asm/sections.h>
11
12 DECLARE_GLOBAL_DATA_PTR;
13
14 static char trace_enabled __attribute__((section(".data")));
15 static char trace_inited __attribute__((section(".data")));
16
17 /* The header block at the start of the trace memory area */
18 struct trace_hdr {
19 int func_count; /* Total number of function call sites */
20 u64 call_count; /* Total number of tracked function calls */
21 u64 untracked_count; /* Total number of untracked function calls */
22 int funcs_used; /* Total number of functions used */
23
24 /*
25 * Call count for each function. This is indexed by the word offset
26 * of the function from gd->relocaddr
27 */
28 uintptr_t *call_accum;
29
30 /* Function trace list */
31 struct trace_call *ftrace; /* The function call records */
32 ulong ftrace_size; /* Num. of ftrace records we have space for */
33 ulong ftrace_count; /* Num. of ftrace records written */
34 ulong ftrace_too_deep_count; /* Functions that were too deep */
35
36 int depth;
37 int depth_limit;
38 int max_depth;
39 };
40
41 static struct trace_hdr *hdr; /* Pointer to start of trace buffer */
42
43 static inline uintptr_t __attribute__((no_instrument_function))
func_ptr_to_num(void * func_ptr)44 func_ptr_to_num(void *func_ptr)
45 {
46 uintptr_t offset = (uintptr_t)func_ptr;
47
48 #ifdef CONFIG_SANDBOX
49 offset -= (uintptr_t)&_init;
50 #else
51 if (gd->flags & GD_FLG_RELOC)
52 offset -= gd->relocaddr;
53 else
54 offset -= CONFIG_SYS_TEXT_BASE;
55 #endif
56 return offset / FUNC_SITE_SIZE;
57 }
58
add_ftrace(void * func_ptr,void * caller,ulong flags)59 static void __attribute__((no_instrument_function)) add_ftrace(void *func_ptr,
60 void *caller, ulong flags)
61 {
62 if (hdr->depth > hdr->depth_limit) {
63 hdr->ftrace_too_deep_count++;
64 return;
65 }
66 if (hdr->ftrace_count < hdr->ftrace_size) {
67 struct trace_call *rec = &hdr->ftrace[hdr->ftrace_count];
68
69 rec->func = func_ptr_to_num(func_ptr);
70 rec->caller = func_ptr_to_num(caller);
71 rec->flags = flags | (timer_get_us() & FUNCF_TIMESTAMP_MASK);
72 }
73 hdr->ftrace_count++;
74 }
75
add_textbase(void)76 static void __attribute__((no_instrument_function)) add_textbase(void)
77 {
78 if (hdr->ftrace_count < hdr->ftrace_size) {
79 struct trace_call *rec = &hdr->ftrace[hdr->ftrace_count];
80
81 rec->func = CONFIG_SYS_TEXT_BASE;
82 rec->caller = 0;
83 rec->flags = FUNCF_TEXTBASE;
84 }
85 hdr->ftrace_count++;
86 }
87
88 /**
89 * This is called on every function entry
90 *
91 * We add to our tally for this function and add to the list of called
92 * functions.
93 *
94 * @param func_ptr Pointer to function being entered
95 * @param caller Pointer to function which called this function
96 */
__cyg_profile_func_enter(void * func_ptr,void * caller)97 void __attribute__((no_instrument_function)) __cyg_profile_func_enter(
98 void *func_ptr, void *caller)
99 {
100 if (trace_enabled) {
101 int func;
102
103 add_ftrace(func_ptr, caller, FUNCF_ENTRY);
104 func = func_ptr_to_num(func_ptr);
105 if (func < hdr->func_count) {
106 hdr->call_accum[func]++;
107 hdr->call_count++;
108 } else {
109 hdr->untracked_count++;
110 }
111 hdr->depth++;
112 if (hdr->depth > hdr->depth_limit)
113 hdr->max_depth = hdr->depth;
114 }
115 }
116
117 /**
118 * This is called on every function exit
119 *
120 * We do nothing here.
121 *
122 * @param func_ptr Pointer to function being entered
123 * @param caller Pointer to function which called this function
124 */
__cyg_profile_func_exit(void * func_ptr,void * caller)125 void __attribute__((no_instrument_function)) __cyg_profile_func_exit(
126 void *func_ptr, void *caller)
127 {
128 if (trace_enabled) {
129 add_ftrace(func_ptr, caller, FUNCF_EXIT);
130 hdr->depth--;
131 }
132 }
133
134 /**
135 * Produce a list of called functions
136 *
137 * The information is written into the supplied buffer - a header followed
138 * by a list of function records.
139 *
140 * @param buff Buffer to place list into
141 * @param buff_size Size of buffer
142 * @param needed Returns size of buffer needed, which may be
143 * greater than buff_size if we ran out of space.
144 * @return 0 if ok, -1 if space was exhausted
145 */
trace_list_functions(void * buff,int buff_size,unsigned int * needed)146 int trace_list_functions(void *buff, int buff_size, unsigned int *needed)
147 {
148 struct trace_output_hdr *output_hdr = NULL;
149 void *end, *ptr = buff;
150 int func;
151 int upto;
152
153 end = buff ? buff + buff_size : NULL;
154
155 /* Place some header information */
156 if (ptr + sizeof(struct trace_output_hdr) < end)
157 output_hdr = ptr;
158 ptr += sizeof(struct trace_output_hdr);
159
160 /* Add information about each function */
161 for (func = upto = 0; func < hdr->func_count; func++) {
162 int calls = hdr->call_accum[func];
163
164 if (!calls)
165 continue;
166
167 if (ptr + sizeof(struct trace_output_func) < end) {
168 struct trace_output_func *stats = ptr;
169
170 stats->offset = func * FUNC_SITE_SIZE;
171 stats->call_count = calls;
172 upto++;
173 }
174 ptr += sizeof(struct trace_output_func);
175 }
176
177 /* Update the header */
178 if (output_hdr) {
179 output_hdr->rec_count = upto;
180 output_hdr->type = TRACE_CHUNK_FUNCS;
181 }
182
183 /* Work out how must of the buffer we used */
184 *needed = ptr - buff;
185 if (ptr > end)
186 return -1;
187 return 0;
188 }
189
trace_list_calls(void * buff,int buff_size,unsigned * needed)190 int trace_list_calls(void *buff, int buff_size, unsigned *needed)
191 {
192 struct trace_output_hdr *output_hdr = NULL;
193 void *end, *ptr = buff;
194 int rec, upto;
195 int count;
196
197 end = buff ? buff + buff_size : NULL;
198
199 /* Place some header information */
200 if (ptr + sizeof(struct trace_output_hdr) < end)
201 output_hdr = ptr;
202 ptr += sizeof(struct trace_output_hdr);
203
204 /* Add information about each call */
205 count = hdr->ftrace_count;
206 if (count > hdr->ftrace_size)
207 count = hdr->ftrace_size;
208 for (rec = upto = 0; rec < count; rec++) {
209 if (ptr + sizeof(struct trace_call) < end) {
210 struct trace_call *call = &hdr->ftrace[rec];
211 struct trace_call *out = ptr;
212
213 out->func = call->func * FUNC_SITE_SIZE;
214 out->caller = call->caller * FUNC_SITE_SIZE;
215 out->flags = call->flags;
216 upto++;
217 }
218 ptr += sizeof(struct trace_call);
219 }
220
221 /* Update the header */
222 if (output_hdr) {
223 output_hdr->rec_count = upto;
224 output_hdr->type = TRACE_CHUNK_CALLS;
225 }
226
227 /* Work out how must of the buffer we used */
228 *needed = ptr - buff;
229 if (ptr > end)
230 return -1;
231 return 0;
232 }
233
234 /* Print basic information about tracing */
trace_print_stats(void)235 void trace_print_stats(void)
236 {
237 ulong count;
238
239 #ifndef FTRACE
240 puts("Warning: make U-Boot with FTRACE to enable function instrumenting.\n");
241 puts("You will likely get zeroed data here\n");
242 #endif
243 if (!trace_inited) {
244 printf("Trace is disabled\n");
245 return;
246 }
247 print_grouped_ull(hdr->func_count, 10);
248 puts(" function sites\n");
249 print_grouped_ull(hdr->call_count, 10);
250 puts(" function calls\n");
251 print_grouped_ull(hdr->untracked_count, 10);
252 puts(" untracked function calls\n");
253 count = min(hdr->ftrace_count, hdr->ftrace_size);
254 print_grouped_ull(count, 10);
255 puts(" traced function calls");
256 if (hdr->ftrace_count > hdr->ftrace_size) {
257 printf(" (%lu dropped due to overflow)",
258 hdr->ftrace_count - hdr->ftrace_size);
259 }
260 puts("\n");
261 printf("%15d maximum observed call depth\n", hdr->max_depth);
262 printf("%15d call depth limit\n", hdr->depth_limit);
263 print_grouped_ull(hdr->ftrace_too_deep_count, 10);
264 puts(" calls not traced due to depth\n");
265 }
266
trace_set_enabled(int enabled)267 void __attribute__((no_instrument_function)) trace_set_enabled(int enabled)
268 {
269 trace_enabled = enabled != 0;
270 }
271
272 /**
273 * Init the tracing system ready for used, and enable it
274 *
275 * @param buff Pointer to trace buffer
276 * @param buff_size Size of trace buffer
277 */
trace_init(void * buff,size_t buff_size)278 int __attribute__((no_instrument_function)) trace_init(void *buff,
279 size_t buff_size)
280 {
281 ulong func_count = gd->mon_len / FUNC_SITE_SIZE;
282 size_t needed;
283 int was_disabled = !trace_enabled;
284
285 if (!was_disabled) {
286 #ifdef CONFIG_TRACE_EARLY
287 char *end;
288 ulong used;
289
290 /*
291 * Copy over the early trace data if we have it. Disable
292 * tracing while we are doing this.
293 */
294 trace_enabled = 0;
295 hdr = map_sysmem(CONFIG_TRACE_EARLY_ADDR,
296 CONFIG_TRACE_EARLY_SIZE);
297 end = (char *)&hdr->ftrace[hdr->ftrace_count];
298 used = end - (char *)hdr;
299 printf("trace: copying %08lx bytes of early data from %x to %08lx\n",
300 used, CONFIG_TRACE_EARLY_ADDR,
301 (ulong)map_to_sysmem(buff));
302 memcpy(buff, hdr, used);
303 #else
304 puts("trace: already enabled\n");
305 return -1;
306 #endif
307 }
308 hdr = (struct trace_hdr *)buff;
309 needed = sizeof(*hdr) + func_count * sizeof(uintptr_t);
310 if (needed > buff_size) {
311 printf("trace: buffer size %zd bytes: at least %zd needed\n",
312 buff_size, needed);
313 return -1;
314 }
315
316 if (was_disabled)
317 memset(hdr, '\0', needed);
318 hdr->func_count = func_count;
319 hdr->call_accum = (uintptr_t *)(hdr + 1);
320
321 /* Use any remaining space for the timed function trace */
322 hdr->ftrace = (struct trace_call *)(buff + needed);
323 hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
324 add_textbase();
325
326 puts("trace: enabled\n");
327 hdr->depth_limit = 15;
328 trace_enabled = 1;
329 trace_inited = 1;
330 return 0;
331 }
332
333 #ifdef CONFIG_TRACE_EARLY
trace_early_init(void)334 int __attribute__((no_instrument_function)) trace_early_init(void)
335 {
336 ulong func_count = gd->mon_len / FUNC_SITE_SIZE;
337 size_t buff_size = CONFIG_TRACE_EARLY_SIZE;
338 size_t needed;
339
340 /* We can ignore additional calls to this function */
341 if (trace_enabled)
342 return 0;
343
344 hdr = map_sysmem(CONFIG_TRACE_EARLY_ADDR, CONFIG_TRACE_EARLY_SIZE);
345 needed = sizeof(*hdr) + func_count * sizeof(uintptr_t);
346 if (needed > buff_size) {
347 printf("trace: buffer size is %zd bytes, at least %zd needed\n",
348 buff_size, needed);
349 return -1;
350 }
351
352 memset(hdr, '\0', needed);
353 hdr->call_accum = (uintptr_t *)(hdr + 1);
354 hdr->func_count = func_count;
355
356 /* Use any remaining space for the timed function trace */
357 hdr->ftrace = (struct trace_call *)((char *)hdr + needed);
358 hdr->ftrace_size = (buff_size - needed) / sizeof(*hdr->ftrace);
359 add_textbase();
360 hdr->depth_limit = 200;
361 printf("trace: early enable at %08x\n", CONFIG_TRACE_EARLY_ADDR);
362
363 trace_enabled = 1;
364 return 0;
365 }
366 #endif
367