aboutsummaryrefslogtreecommitdiff
path: root/tools/perf/builtin-diff.c
blob: a6e2fdc7a04e16613087a4c65e70d832ab903505 (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
/*
 * builtin-diff.c
 *
 * Builtin diff command: Analyze two perf.data input files, look up and read
 * DSOs and symbol information, sort them and produce a diff.
 */
#include "builtin.h"

#include "util/debug.h"
#include "util/event.h"
#include "util/hist.h"
#include "util/session.h"
#include "util/sort.h"
#include "util/symbol.h"
#include "util/util.h"

#include <stdlib.h>

static char const *input_old = "perf.data.old",
		  *input_new = "perf.data";
static char	  diff__default_sort_order[] = "dso,symbol";
static bool  force;
static bool show_displacement;

static int hists__add_entry(struct hists *self,
			    struct addr_location *al, u64 period)
{
	if (__hists__add_entry(self, al, NULL, period) != NULL)
		return 0;
	return -ENOMEM;
}

static int diff__process_sample_event(event_t *event, struct perf_session *session)
{
	struct addr_location al;
	struct sample_data data = { .period = 1, };

	dump_printf("(IP, %d): %d: %#Lx\n", event->header.misc,
		    event->ip.pid, event->ip.ip);

	if (event__preprocess_sample(event, session, &al, NULL) < 0) {
		pr_warning("problem processing %d event, skipping it.\n",
			   event->header.type);
		return -1;
	}

	if (al.filtered || al.sym == NULL)
		return 0;

	event__parse_sample(event, session->sample_type, &data);

	if (hists__add_entry(&session->hists, &al, data.period)) {
		pr_warning("problem incrementing symbol period, skipping event\n");
		return -1;
	}

	session->hists.stats.total_period += data.period;
	return 0;
}

static struct perf_event_ops event_ops = {
	.sample	= diff__process_sample_event,
	.mmap	= event__process_mmap,
	.comm	= event__process_comm,
	.exit	= event__process_task,
	.fork	= event__process_task,
	.lost	= event__process_lost,
};

static void perf_session__insert_hist_entry_by_name(struct rb_root *root,
						    struct hist_entry *he)
{
	struct rb_node **p = &root->rb_node;
	struct rb_node *parent = NULL;
	struct hist_entry *iter;

	while (*p != NULL) {
		parent = *p;
		iter = rb_entry(parent, struct hist_entry, rb_node);
		if (hist_entry__cmp(he, iter) < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}

	rb_link_node(&he->rb_node, parent, p);
	rb_insert_color(&he->rb_node, root);
}

static void hists__resort_entries(struct hists *self)
{
	unsigned long position = 1;
	struct rb_root tmp = RB_ROOT;
	struct rb_node *next = rb_first(&self->entries);

	while (next != NULL) {
		struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);

		next = rb_next(&n->rb_node);
		rb_erase(&n->rb_node, &self->entries);
		n->position = position++;
		perf_session__insert_hist_entry_by_name(&tmp, n);
	}

	self->entries = tmp;
}

static void hists__set_positions(struct hists *self)
{
	hists__output_resort(self);
	hists__resort_entries(self);
}

static struct hist_entry *hists__find_entry(struct hists *self,
					    struct hist_entry *he)
{
	struct rb_node *n = self->entries.rb_node;

	while (n) {
		struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
		int64_t cmp = hist_entry__cmp(he, iter);

		if (cmp < 0)
			n = n->rb_left;
		else if (cmp > 0)
			n = n->rb_right;
		else 
			return iter;
	}

	return NULL;
}

static void hists__match(struct hists *older, struct hists *newer)
{
	struct rb_node *nd;

	for (nd = rb_first(&newer->entries); nd; nd = rb_next(nd)) {
		struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
		pos->pair = hists__find_entry(older, pos);
	}
}

static int __cmd_diff(void)
{
	int ret, i;
	struct perf_session *session[2];

	session[0] = perf_session__new(input_old, O_RDONLY, force, false);
	session[1] = perf_session__new(input_new, O_RDONLY, force, false);
	if (session[0] == NULL || session[1] == NULL)
		return -ENOMEM;

	for (i = 0; i < 2; ++i) {
		ret = perf_session__process_events(session[i], &event_ops);
		if (ret)
			goto out_delete;
	}

	hists__output_resort(&session[1]->hists);
	if (show_displacement)
		hists__set_positions(&session[0]->hists);

	hists__match(&session[0]->hists, &session[1]->hists);
	hists__fprintf(&session[1]->hists, &session[0]->hists,
		       show_displacement, stdout);
out_delete:
	for (i = 0; i < 2; ++i)
		perf_session__delete(session[i]);
	return ret;
}

static const char * const diff_usage[] = {
	"perf diff [<options>] [old_file] [new_file]",
	NULL,
};

static const struct option options[] = {
	OPT_INCR('v', "verbose", &verbose,
		    "be more verbose (show symbol address, etc)"),
	OPT_BOOLEAN('m', "displacement", &show_displacement,
		    "Show position displacement relative to baseline"),
	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
		    "dump raw trace in ASCII"),
	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
	OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
		    "load module symbols - WARNING: use only with -k and LIVE kernel"),
	OPT_BOOLEAN('P', "full-paths", &symbol_conf.full_paths,
		    "Don't shorten the pathnames taking into account the cwd"),
	OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
		   "only consider symbols in these dsos"),
	OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
		   "only consider symbols in these comms"),
	OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
		   "only consider these symbols"),
	OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
		   "sort by key(s): pid, comm, dso, symbol, parent"),
	OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
		   "separator for columns, no spaces will be added between "
		   "columns '.' is reserved."),
	OPT_END()
};

int cmd_diff(int argc, const char **argv, const char *prefix __used)
{
	sort_order = diff__default_sort_order;
	argc = parse_options(argc, argv, options, diff_usage, 0);
	if (argc) {
		if (argc > 2)
			usage_with_options(diff_usage, options);
		if (argc == 2) {
			input_old = argv[0];
			input_new = argv[1];
		} else
			input_new = argv[0];
	} else if (symbol_conf.default_guest_vmlinux_name ||
		   symbol_conf.default_guest_kallsyms) {
		input_old = "perf.data.host";
		input_new = "perf.data.guest";
	}

	symbol_conf.exclude_other = false;
	if (symbol__init() < 0)
		return -1;

	setup_sorting(diff_usage, options);
	setup_pager();

	sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
	sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
	sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);

	return __cmd_diff();
}