summaryrefslogtreecommitdiff
path: root/tools/perf/util/data_map.c
blob: c458db9ede6d00b68fb209a70978cf0efedbb8f9 (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
#include "data_map.h"
#include "symbol.h"
#include "util.h"
#include "debug.h"


static struct perf_file_handler *curr_handler;
static unsigned long	mmap_window = 32;
static char		__cwd[PATH_MAX];

static int
process_event_stub(event_t *event __used,
		   unsigned long offset __used,
		   unsigned long head __used)
{
	return 0;
}

void register_perf_file_handler(struct perf_file_handler *handler)
{
	if (!handler->process_sample_event)
		handler->process_sample_event = process_event_stub;
	if (!handler->process_mmap_event)
		handler->process_mmap_event = process_event_stub;
	if (!handler->process_comm_event)
		handler->process_comm_event = process_event_stub;
	if (!handler->process_fork_event)
		handler->process_fork_event = process_event_stub;
	if (!handler->process_exit_event)
		handler->process_exit_event = process_event_stub;
	if (!handler->process_lost_event)
		handler->process_lost_event = process_event_stub;
	if (!handler->process_read_event)
		handler->process_read_event = process_event_stub;
	if (!handler->process_throttle_event)
		handler->process_throttle_event = process_event_stub;
	if (!handler->process_unthrottle_event)
		handler->process_unthrottle_event = process_event_stub;

	curr_handler = handler;
}

static int
process_event(event_t *event, unsigned long offset, unsigned long head)
{
	trace_event(event);

	switch (event->header.type) {
	case PERF_RECORD_SAMPLE:
		return curr_handler->process_sample_event(event, offset, head);
	case PERF_RECORD_MMAP:
		return curr_handler->process_mmap_event(event, offset, head);
	case PERF_RECORD_COMM:
		return curr_handler->process_comm_event(event, offset, head);
	case PERF_RECORD_FORK:
		return curr_handler->process_fork_event(event, offset, head);
	case PERF_RECORD_EXIT:
		return curr_handler->process_exit_event(event, offset, head);
	case PERF_RECORD_LOST:
		return curr_handler->process_lost_event(event, offset, head);
	case PERF_RECORD_READ:
		return curr_handler->process_read_event(event, offset, head);
	case PERF_RECORD_THROTTLE:
		return curr_handler->process_throttle_event(event, offset, head);
	case PERF_RECORD_UNTHROTTLE:
		return curr_handler->process_unthrottle_event(event, offset, head);
	default:
		curr_handler->total_unknown++;
		return -1;
	}
}

int mmap_dispatch_perf_file(struct perf_header **pheader,
			    const char *input_name,
			    int force,
			    int full_paths,
			    int *cwdlen,
			    char **cwd)
{
	int ret, rc = EXIT_FAILURE;
	struct perf_header *header;
	unsigned long head, shift;
	unsigned long offset = 0;
	struct stat input_stat;
	size_t	page_size;
	u64 sample_type;
	event_t *event;
	uint32_t size;
	int input;
	char *buf;

	if (!curr_handler)
		die("Forgot to register perf file handler");

	page_size = getpagesize();

	input = open(input_name, O_RDONLY);
	if (input < 0) {
		fprintf(stderr, " failed to open file: %s", input_name);
		if (!strcmp(input_name, "perf.data"))
			fprintf(stderr, "  (try 'perf record' first)");
		fprintf(stderr, "\n");
		exit(-1);
	}

	ret = fstat(input, &input_stat);
	if (ret < 0) {
		perror("failed to stat file");
		exit(-1);
	}

	if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
		fprintf(stderr, "file: %s not owned by current user or root\n",
			input_name);
		exit(-1);
	}

	if (!input_stat.st_size) {
		fprintf(stderr, "zero-sized file, nothing to do!\n");
		exit(0);
	}

	*pheader = perf_header__read(input);
	header = *pheader;
	head = header->data_offset;

	sample_type = perf_header__sample_type(header);

	if (curr_handler->sample_type_check)
		if (curr_handler->sample_type_check(sample_type) < 0)
			exit(-1);

	if (load_kernel(NULL) < 0) {
		perror("failed to load kernel symbols");
		return EXIT_FAILURE;
	}

	if (!full_paths) {
		if (getcwd(__cwd, sizeof(__cwd)) == NULL) {
			perror("failed to get the current directory");
			return EXIT_FAILURE;
		}
		*cwd = __cwd;
		*cwdlen = strlen(*cwd);
	} else {
		*cwd = NULL;
		*cwdlen = 0;
	}

	shift = page_size * (head / page_size);
	offset += shift;
	head -= shift;

remap:
	buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
			   MAP_SHARED, input, offset);
	if (buf == MAP_FAILED) {
		perror("failed to mmap file");
		exit(-1);
	}

more:
	event = (event_t *)(buf + head);

	size = event->header.size;
	if (!size)
		size = 8;

	if (head + event->header.size >= page_size * mmap_window) {
		int munmap_ret;

		shift = page_size * (head / page_size);

		munmap_ret = munmap(buf, page_size * mmap_window);
		assert(munmap_ret == 0);

		offset += shift;
		head -= shift;
		goto remap;
	}

	size = event->header.size;

	dump_printf("\n%p [%p]: event: %d\n",
			(void *)(offset + head),
			(void *)(long)event->header.size,
			event->header.type);

	if (!size || process_event(event, offset, head) < 0) {

		dump_printf("%p [%p]: skipping unknown header type: %d\n",
			(void *)(offset + head),
			(void *)(long)(event->header.size),
			event->header.type);

		/*
		 * assume we lost track of the stream, check alignment, and
		 * increment a single u64 in the hope to catch on again 'soon'.
		 */

		if (unlikely(head & 7))
			head &= ~7ULL;

		size = 8;
	}

	head += size;

	if (offset + head >= header->data_offset + header->data_size)
		goto done;

	if (offset + head < (unsigned long)input_stat.st_size)
		goto more;

done:
	rc = EXIT_SUCCESS;
	close(input);

	return rc;
}