summaryrefslogtreecommitdiff
path: root/tools/perf/util/dsos.c
blob: cf80aa42dd07b036e3ed7816a22e90e96ef94581 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
// SPDX-License-Identifier: GPL-2.0
#include "debug.h"
#include "dsos.h"
#include "dso.h"
#include "util.h"
#include "vdso.h"
#include "namespaces.h"
#include <errno.h>
#include <libgen.h>
#include <stdlib.h>
#include <string.h>
#include <symbol.h> // filename__read_build_id
#include <unistd.h>

static int __dso_id__cmp(struct dso_id *a, struct dso_id *b)
{
	if (a->maj > b->maj) return -1;
	if (a->maj < b->maj) return 1;

	if (a->min > b->min) return -1;
	if (a->min < b->min) return 1;

	if (a->ino > b->ino) return -1;
	if (a->ino < b->ino) return 1;

	/*
	 * Synthesized MMAP events have zero ino_generation, avoid comparing
	 * them with MMAP events with actual ino_generation.
	 *
	 * I found it harmful because the mismatch resulted in a new
	 * dso that did not have a build ID whereas the original dso did have a
	 * build ID. The build ID was essential because the object was not found
	 * otherwise. - Adrian
	 */
	if (a->ino_generation && b->ino_generation) {
		if (a->ino_generation > b->ino_generation) return -1;
		if (a->ino_generation < b->ino_generation) return 1;
	}

	return 0;
}

static bool dso_id__empty(struct dso_id *id)
{
	if (!id)
		return true;

	return !id->maj && !id->min && !id->ino && !id->ino_generation;
}

static void dso__inject_id(struct dso *dso, struct dso_id *id)
{
	dso->id.maj = id->maj;
	dso->id.min = id->min;
	dso->id.ino = id->ino;
	dso->id.ino_generation = id->ino_generation;
}

static int dso_id__cmp(struct dso_id *a, struct dso_id *b)
{
	/*
	 * The second is always dso->id, so zeroes if not set, assume passing
	 * NULL for a means a zeroed id
	 */
	if (dso_id__empty(a) || dso_id__empty(b))
		return 0;

	return __dso_id__cmp(a, b);
}

int dso__cmp_id(struct dso *a, struct dso *b)
{
	return __dso_id__cmp(&a->id, &b->id);
}

bool __dsos__read_build_ids(struct list_head *head, bool with_hits)
{
	bool have_build_id = false;
	struct dso *pos;
	struct nscookie nsc;

	list_for_each_entry(pos, head, node) {
		if (with_hits && !pos->hit && !dso__is_vdso(pos))
			continue;
		if (pos->has_build_id) {
			have_build_id = true;
			continue;
		}
		nsinfo__mountns_enter(pos->nsinfo, &nsc);
		if (filename__read_build_id(pos->long_name, &pos->bid) > 0) {
			have_build_id	  = true;
			pos->has_build_id = true;
		} else if (errno == ENOENT && pos->nsinfo) {
			char *new_name = dso__filename_with_chroot(pos, pos->long_name);

			if (new_name && filename__read_build_id(new_name,
								&pos->bid) > 0) {
				have_build_id = true;
				pos->has_build_id = true;
			}
			free(new_name);
		}
		nsinfo__mountns_exit(&nsc);
	}

	return have_build_id;
}

static int __dso__cmp_long_name(const char *long_name, struct dso_id *id, struct dso *b)
{
	int rc = strcmp(long_name, b->long_name);
	return rc ?: dso_id__cmp(id, &b->id);
}

static int __dso__cmp_short_name(const char *short_name, struct dso_id *id, struct dso *b)
{
	int rc = strcmp(short_name, b->short_name);
	return rc ?: dso_id__cmp(id, &b->id);
}

static int dso__cmp_short_name(struct dso *a, struct dso *b)
{
	return __dso__cmp_short_name(a->short_name, &a->id, b);
}

/*
 * Find a matching entry and/or link current entry to RB tree.
 * Either one of the dso or name parameter must be non-NULL or the
 * function will not work.
 */
struct dso *__dsos__findnew_link_by_longname_id(struct rb_root *root, struct dso *dso,
						const char *name, struct dso_id *id)
{
	struct rb_node **p = &root->rb_node;
	struct rb_node  *parent = NULL;

	if (!name)
		name = dso->long_name;
	/*
	 * Find node with the matching name
	 */
	while (*p) {
		struct dso *this = rb_entry(*p, struct dso, rb_node);
		int rc = __dso__cmp_long_name(name, id, this);

		parent = *p;
		if (rc == 0) {
			/*
			 * In case the new DSO is a duplicate of an existing
			 * one, print a one-time warning & put the new entry
			 * at the end of the list of duplicates.
			 */
			if (!dso || (dso == this))
				return this;	/* Find matching dso */
			/*
			 * The core kernel DSOs may have duplicated long name.
			 * In this case, the short name should be different.
			 * Comparing the short names to differentiate the DSOs.
			 */
			rc = dso__cmp_short_name(dso, this);
			if (rc == 0) {
				pr_err("Duplicated dso name: %s\n", name);
				return NULL;
			}
		}
		if (rc < 0)
			p = &parent->rb_left;
		else
			p = &parent->rb_right;
	}
	if (dso) {
		/* Add new node and rebalance tree */
		rb_link_node(&dso->rb_node, parent, p);
		rb_insert_color(&dso->rb_node, root);
		dso->root = root;
	}
	return NULL;
}

void __dsos__add(struct dsos *dsos, struct dso *dso)
{
	list_add_tail(&dso->node, &dsos->head);
	__dsos__findnew_link_by_longname_id(&dsos->root, dso, NULL, &dso->id);
	/*
	 * It is now in the linked list, grab a reference, then garbage collect
	 * this when needing memory, by looking at LRU dso instances in the
	 * list with atomic_read(&dso->refcnt) == 1, i.e. no references
	 * anywhere besides the one for the list, do, under a lock for the
	 * list: remove it from the list, then a dso__put(), that probably will
	 * be the last and will then call dso__delete(), end of life.
	 *
	 * That, or at the end of the 'struct machine' lifetime, when all
	 * 'struct dso' instances will be removed from the list, in
	 * dsos__exit(), if they have no other reference from some other data
	 * structure.
	 *
	 * E.g.: after processing a 'perf.data' file and storing references
	 * to objects instantiated while processing events, we will have
	 * references to the 'thread', 'map', 'dso' structs all from 'struct
	 * hist_entry' instances, but we may not need anything not referenced,
	 * so we might as well call machines__exit()/machines__delete() and
	 * garbage collect it.
	 */
	dso__get(dso);
}

void dsos__add(struct dsos *dsos, struct dso *dso)
{
	down_write(&dsos->lock);
	__dsos__add(dsos, dso);
	up_write(&dsos->lock);
}

static struct dso *__dsos__findnew_by_longname_id(struct rb_root *root, const char *name, struct dso_id *id)
{
	return __dsos__findnew_link_by_longname_id(root, NULL, name, id);
}

static struct dso *__dsos__find_id(struct dsos *dsos, const char *name, struct dso_id *id, bool cmp_short)
{
	struct dso *pos;

	if (cmp_short) {
		list_for_each_entry(pos, &dsos->head, node)
			if (__dso__cmp_short_name(name, id, pos) == 0)
				return pos;
		return NULL;
	}
	return __dsos__findnew_by_longname_id(&dsos->root, name, id);
}

struct dso *__dsos__find(struct dsos *dsos, const char *name, bool cmp_short)
{
	return __dsos__find_id(dsos, name, NULL, cmp_short);
}

static void dso__set_basename(struct dso *dso)
{
	char *base, *lname;
	int tid;

	if (sscanf(dso->long_name, "/tmp/perf-%d.map", &tid) == 1) {
		if (asprintf(&base, "[JIT] tid %d", tid) < 0)
			return;
	} else {
	      /*
	       * basename() may modify path buffer, so we must pass
               * a copy.
               */
		lname = strdup(dso->long_name);
		if (!lname)
			return;

		/*
		 * basename() may return a pointer to internal
		 * storage which is reused in subsequent calls
		 * so copy the result.
		 */
		base = strdup(basename(lname));

		free(lname);

		if (!base)
			return;
	}
	dso__set_short_name(dso, base, true);
}

static struct dso *__dsos__addnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
{
	struct dso *dso = dso__new_id(name, id);

	if (dso != NULL) {
		__dsos__add(dsos, dso);
		dso__set_basename(dso);
		/* Put dso here because __dsos_add already got it */
		dso__put(dso);
	}
	return dso;
}

struct dso *__dsos__addnew(struct dsos *dsos, const char *name)
{
	return __dsos__addnew_id(dsos, name, NULL);
}

static struct dso *__dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
{
	struct dso *dso = __dsos__find_id(dsos, name, id, false);

	if (dso && dso_id__empty(&dso->id) && !dso_id__empty(id))
		dso__inject_id(dso, id);

	return dso ? dso : __dsos__addnew_id(dsos, name, id);
}

struct dso *dsos__findnew_id(struct dsos *dsos, const char *name, struct dso_id *id)
{
	struct dso *dso;
	down_write(&dsos->lock);
	dso = dso__get(__dsos__findnew_id(dsos, name, id));
	up_write(&dsos->lock);
	return dso;
}

size_t __dsos__fprintf_buildid(struct list_head *head, FILE *fp,
			       bool (skip)(struct dso *dso, int parm), int parm)
{
	struct dso *pos;
	size_t ret = 0;

	list_for_each_entry(pos, head, node) {
		char sbuild_id[SBUILD_ID_SIZE];

		if (skip && skip(pos, parm))
			continue;
		build_id__sprintf(&pos->bid, sbuild_id);
		ret += fprintf(fp, "%-40s %s\n", sbuild_id, pos->long_name);
	}
	return ret;
}

size_t __dsos__fprintf(struct list_head *head, FILE *fp)
{
	struct dso *pos;
	size_t ret = 0;

	list_for_each_entry(pos, head, node) {
		ret += dso__fprintf(pos, fp);
	}

	return ret;
}