xref: /linux/tools/perf/util/machine.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 #include "debug.h"
2 #include "event.h"
3 #include "machine.h"
4 #include "map.h"
5 #include "strlist.h"
6 #include "thread.h"
7 #include <stdbool.h>
8 
9 int machine__init(struct machine *machine, const char *root_dir, pid_t pid)
10 {
11 	map_groups__init(&machine->kmaps);
12 	RB_CLEAR_NODE(&machine->rb_node);
13 	INIT_LIST_HEAD(&machine->user_dsos);
14 	INIT_LIST_HEAD(&machine->kernel_dsos);
15 
16 	machine->threads = RB_ROOT;
17 	INIT_LIST_HEAD(&machine->dead_threads);
18 	machine->last_match = NULL;
19 
20 	machine->kmaps.machine = machine;
21 	machine->pid = pid;
22 
23 	machine->root_dir = strdup(root_dir);
24 	if (machine->root_dir == NULL)
25 		return -ENOMEM;
26 
27 	if (pid != HOST_KERNEL_ID) {
28 		struct thread *thread = machine__findnew_thread(machine, pid);
29 		char comm[64];
30 
31 		if (thread == NULL)
32 			return -ENOMEM;
33 
34 		snprintf(comm, sizeof(comm), "[guest/%d]", pid);
35 		thread__set_comm(thread, comm);
36 	}
37 
38 	return 0;
39 }
40 
41 static void dsos__delete(struct list_head *dsos)
42 {
43 	struct dso *pos, *n;
44 
45 	list_for_each_entry_safe(pos, n, dsos, node) {
46 		list_del(&pos->node);
47 		dso__delete(pos);
48 	}
49 }
50 
51 void machine__exit(struct machine *machine)
52 {
53 	map_groups__exit(&machine->kmaps);
54 	dsos__delete(&machine->user_dsos);
55 	dsos__delete(&machine->kernel_dsos);
56 	free(machine->root_dir);
57 	machine->root_dir = NULL;
58 }
59 
60 void machine__delete(struct machine *machine)
61 {
62 	machine__exit(machine);
63 	free(machine);
64 }
65 
66 struct machine *machines__add(struct rb_root *machines, pid_t pid,
67 			      const char *root_dir)
68 {
69 	struct rb_node **p = &machines->rb_node;
70 	struct rb_node *parent = NULL;
71 	struct machine *pos, *machine = malloc(sizeof(*machine));
72 
73 	if (machine == NULL)
74 		return NULL;
75 
76 	if (machine__init(machine, root_dir, pid) != 0) {
77 		free(machine);
78 		return NULL;
79 	}
80 
81 	while (*p != NULL) {
82 		parent = *p;
83 		pos = rb_entry(parent, struct machine, rb_node);
84 		if (pid < pos->pid)
85 			p = &(*p)->rb_left;
86 		else
87 			p = &(*p)->rb_right;
88 	}
89 
90 	rb_link_node(&machine->rb_node, parent, p);
91 	rb_insert_color(&machine->rb_node, machines);
92 
93 	return machine;
94 }
95 
96 struct machine *machines__find(struct rb_root *machines, pid_t pid)
97 {
98 	struct rb_node **p = &machines->rb_node;
99 	struct rb_node *parent = NULL;
100 	struct machine *machine;
101 	struct machine *default_machine = NULL;
102 
103 	while (*p != NULL) {
104 		parent = *p;
105 		machine = rb_entry(parent, struct machine, rb_node);
106 		if (pid < machine->pid)
107 			p = &(*p)->rb_left;
108 		else if (pid > machine->pid)
109 			p = &(*p)->rb_right;
110 		else
111 			return machine;
112 		if (!machine->pid)
113 			default_machine = machine;
114 	}
115 
116 	return default_machine;
117 }
118 
119 struct machine *machines__findnew(struct rb_root *machines, pid_t pid)
120 {
121 	char path[PATH_MAX];
122 	const char *root_dir = "";
123 	struct machine *machine = machines__find(machines, pid);
124 
125 	if (machine && (machine->pid == pid))
126 		goto out;
127 
128 	if ((pid != HOST_KERNEL_ID) &&
129 	    (pid != DEFAULT_GUEST_KERNEL_ID) &&
130 	    (symbol_conf.guestmount)) {
131 		sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
132 		if (access(path, R_OK)) {
133 			static struct strlist *seen;
134 
135 			if (!seen)
136 				seen = strlist__new(true, NULL);
137 
138 			if (!strlist__has_entry(seen, path)) {
139 				pr_err("Can't access file %s\n", path);
140 				strlist__add(seen, path);
141 			}
142 			machine = NULL;
143 			goto out;
144 		}
145 		root_dir = path;
146 	}
147 
148 	machine = machines__add(machines, pid, root_dir);
149 out:
150 	return machine;
151 }
152 
153 void machines__process(struct rb_root *machines,
154 		       machine__process_t process, void *data)
155 {
156 	struct rb_node *nd;
157 
158 	for (nd = rb_first(machines); nd; nd = rb_next(nd)) {
159 		struct machine *pos = rb_entry(nd, struct machine, rb_node);
160 		process(pos, data);
161 	}
162 }
163 
164 char *machine__mmap_name(struct machine *machine, char *bf, size_t size)
165 {
166 	if (machine__is_host(machine))
167 		snprintf(bf, size, "[%s]", "kernel.kallsyms");
168 	else if (machine__is_default_guest(machine))
169 		snprintf(bf, size, "[%s]", "guest.kernel.kallsyms");
170 	else {
171 		snprintf(bf, size, "[%s.%d]", "guest.kernel.kallsyms",
172 			 machine->pid);
173 	}
174 
175 	return bf;
176 }
177 
178 void machines__set_id_hdr_size(struct rb_root *machines, u16 id_hdr_size)
179 {
180 	struct rb_node *node;
181 	struct machine *machine;
182 
183 	for (node = rb_first(machines); node; node = rb_next(node)) {
184 		machine = rb_entry(node, struct machine, rb_node);
185 		machine->id_hdr_size = id_hdr_size;
186 	}
187 
188 	return;
189 }
190 
191 static struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid,
192 						bool create)
193 {
194 	struct rb_node **p = &machine->threads.rb_node;
195 	struct rb_node *parent = NULL;
196 	struct thread *th;
197 
198 	/*
199 	 * Font-end cache - PID lookups come in blocks,
200 	 * so most of the time we dont have to look up
201 	 * the full rbtree:
202 	 */
203 	if (machine->last_match && machine->last_match->pid == pid)
204 		return machine->last_match;
205 
206 	while (*p != NULL) {
207 		parent = *p;
208 		th = rb_entry(parent, struct thread, rb_node);
209 
210 		if (th->pid == pid) {
211 			machine->last_match = th;
212 			return th;
213 		}
214 
215 		if (pid < th->pid)
216 			p = &(*p)->rb_left;
217 		else
218 			p = &(*p)->rb_right;
219 	}
220 
221 	if (!create)
222 		return NULL;
223 
224 	th = thread__new(pid);
225 	if (th != NULL) {
226 		rb_link_node(&th->rb_node, parent, p);
227 		rb_insert_color(&th->rb_node, &machine->threads);
228 		machine->last_match = th;
229 	}
230 
231 	return th;
232 }
233 
234 struct thread *machine__findnew_thread(struct machine *machine, pid_t pid)
235 {
236 	return __machine__findnew_thread(machine, pid, true);
237 }
238 
239 struct thread *machine__find_thread(struct machine *machine, pid_t pid)
240 {
241 	return __machine__findnew_thread(machine, pid, false);
242 }
243 
244 int machine__process_comm_event(struct machine *machine, union perf_event *event)
245 {
246 	struct thread *thread = machine__findnew_thread(machine, event->comm.tid);
247 
248 	if (dump_trace)
249 		perf_event__fprintf_comm(event, stdout);
250 
251 	if (thread == NULL || thread__set_comm(thread, event->comm.comm)) {
252 		dump_printf("problem processing PERF_RECORD_COMM, skipping event.\n");
253 		return -1;
254 	}
255 
256 	return 0;
257 }
258 
259 int machine__process_lost_event(struct machine *machine __maybe_unused,
260 				union perf_event *event)
261 {
262 	dump_printf(": id:%" PRIu64 ": lost:%" PRIu64 "\n",
263 		    event->lost.id, event->lost.lost);
264 	return 0;
265 }
266 
267 static void machine__set_kernel_mmap_len(struct machine *machine,
268 					 union perf_event *event)
269 {
270 	int i;
271 
272 	for (i = 0; i < MAP__NR_TYPES; i++) {
273 		machine->vmlinux_maps[i]->start = event->mmap.start;
274 		machine->vmlinux_maps[i]->end   = (event->mmap.start +
275 						   event->mmap.len);
276 		/*
277 		 * Be a bit paranoid here, some perf.data file came with
278 		 * a zero sized synthesized MMAP event for the kernel.
279 		 */
280 		if (machine->vmlinux_maps[i]->end == 0)
281 			machine->vmlinux_maps[i]->end = ~0ULL;
282 	}
283 }
284 
285 static int machine__process_kernel_mmap_event(struct machine *machine,
286 					      union perf_event *event)
287 {
288 	struct map *map;
289 	char kmmap_prefix[PATH_MAX];
290 	enum dso_kernel_type kernel_type;
291 	bool is_kernel_mmap;
292 
293 	machine__mmap_name(machine, kmmap_prefix, sizeof(kmmap_prefix));
294 	if (machine__is_host(machine))
295 		kernel_type = DSO_TYPE_KERNEL;
296 	else
297 		kernel_type = DSO_TYPE_GUEST_KERNEL;
298 
299 	is_kernel_mmap = memcmp(event->mmap.filename,
300 				kmmap_prefix,
301 				strlen(kmmap_prefix) - 1) == 0;
302 	if (event->mmap.filename[0] == '/' ||
303 	    (!is_kernel_mmap && event->mmap.filename[0] == '[')) {
304 
305 		char short_module_name[1024];
306 		char *name, *dot;
307 
308 		if (event->mmap.filename[0] == '/') {
309 			name = strrchr(event->mmap.filename, '/');
310 			if (name == NULL)
311 				goto out_problem;
312 
313 			++name; /* skip / */
314 			dot = strrchr(name, '.');
315 			if (dot == NULL)
316 				goto out_problem;
317 			snprintf(short_module_name, sizeof(short_module_name),
318 					"[%.*s]", (int)(dot - name), name);
319 			strxfrchar(short_module_name, '-', '_');
320 		} else
321 			strcpy(short_module_name, event->mmap.filename);
322 
323 		map = machine__new_module(machine, event->mmap.start,
324 					  event->mmap.filename);
325 		if (map == NULL)
326 			goto out_problem;
327 
328 		name = strdup(short_module_name);
329 		if (name == NULL)
330 			goto out_problem;
331 
332 		map->dso->short_name = name;
333 		map->dso->sname_alloc = 1;
334 		map->end = map->start + event->mmap.len;
335 	} else if (is_kernel_mmap) {
336 		const char *symbol_name = (event->mmap.filename +
337 				strlen(kmmap_prefix));
338 		/*
339 		 * Should be there already, from the build-id table in
340 		 * the header.
341 		 */
342 		struct dso *kernel = __dsos__findnew(&machine->kernel_dsos,
343 						     kmmap_prefix);
344 		if (kernel == NULL)
345 			goto out_problem;
346 
347 		kernel->kernel = kernel_type;
348 		if (__machine__create_kernel_maps(machine, kernel) < 0)
349 			goto out_problem;
350 
351 		machine__set_kernel_mmap_len(machine, event);
352 
353 		/*
354 		 * Avoid using a zero address (kptr_restrict) for the ref reloc
355 		 * symbol. Effectively having zero here means that at record
356 		 * time /proc/sys/kernel/kptr_restrict was non zero.
357 		 */
358 		if (event->mmap.pgoff != 0) {
359 			maps__set_kallsyms_ref_reloc_sym(machine->vmlinux_maps,
360 							 symbol_name,
361 							 event->mmap.pgoff);
362 		}
363 
364 		if (machine__is_default_guest(machine)) {
365 			/*
366 			 * preload dso of guest kernel and modules
367 			 */
368 			dso__load(kernel, machine->vmlinux_maps[MAP__FUNCTION],
369 				  NULL);
370 		}
371 	}
372 	return 0;
373 out_problem:
374 	return -1;
375 }
376 
377 int machine__process_mmap_event(struct machine *machine, union perf_event *event)
378 {
379 	u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
380 	struct thread *thread;
381 	struct map *map;
382 	int ret = 0;
383 
384 	if (dump_trace)
385 		perf_event__fprintf_mmap(event, stdout);
386 
387 	if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL ||
388 	    cpumode == PERF_RECORD_MISC_KERNEL) {
389 		ret = machine__process_kernel_mmap_event(machine, event);
390 		if (ret < 0)
391 			goto out_problem;
392 		return 0;
393 	}
394 
395 	thread = machine__findnew_thread(machine, event->mmap.pid);
396 	if (thread == NULL)
397 		goto out_problem;
398 	map = map__new(&machine->user_dsos, event->mmap.start,
399 			event->mmap.len, event->mmap.pgoff,
400 			event->mmap.pid, event->mmap.filename,
401 			MAP__FUNCTION);
402 	if (map == NULL)
403 		goto out_problem;
404 
405 	thread__insert_map(thread, map);
406 	return 0;
407 
408 out_problem:
409 	dump_printf("problem processing PERF_RECORD_MMAP, skipping event.\n");
410 	return 0;
411 }
412 
413 int machine__process_fork_event(struct machine *machine, union perf_event *event)
414 {
415 	struct thread *thread = machine__findnew_thread(machine, event->fork.tid);
416 	struct thread *parent = machine__findnew_thread(machine, event->fork.ptid);
417 
418 	if (dump_trace)
419 		perf_event__fprintf_task(event, stdout);
420 
421 	if (thread == NULL || parent == NULL ||
422 	    thread__fork(thread, parent) < 0) {
423 		dump_printf("problem processing PERF_RECORD_FORK, skipping event.\n");
424 		return -1;
425 	}
426 
427 	return 0;
428 }
429 
430 int machine__process_exit_event(struct machine *machine, union perf_event *event)
431 {
432 	struct thread *thread = machine__find_thread(machine, event->fork.tid);
433 
434 	if (dump_trace)
435 		perf_event__fprintf_task(event, stdout);
436 
437 	if (thread != NULL)
438 		machine__remove_thread(machine, thread);
439 
440 	return 0;
441 }
442 
443 int machine__process_event(struct machine *machine, union perf_event *event)
444 {
445 	int ret;
446 
447 	switch (event->header.type) {
448 	case PERF_RECORD_COMM:
449 		ret = machine__process_comm_event(machine, event); break;
450 	case PERF_RECORD_MMAP:
451 		ret = machine__process_mmap_event(machine, event); break;
452 	case PERF_RECORD_FORK:
453 		ret = machine__process_fork_event(machine, event); break;
454 	case PERF_RECORD_EXIT:
455 		ret = machine__process_exit_event(machine, event); break;
456 	case PERF_RECORD_LOST:
457 		ret = machine__process_lost_event(machine, event); break;
458 	default:
459 		ret = -1;
460 		break;
461 	}
462 
463 	return ret;
464 }
465