Commit | Line | Data |
---|---|---|
d76c5b81 AB |
1 | /* |
2 | * blktrace output analysis: generate a timeline & gather statistics | |
3 | * | |
4 | * Copyright (C) 2006 Alan D. Brunelle <Alan.Brunelle@hp.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
19 | * | |
20 | */ | |
21 | ||
22 | #include <stdio.h> | |
23 | #include <unistd.h> | |
24 | #include <sys/types.h> | |
25 | #include <sys/stat.h> | |
26 | #include <fcntl.h> | |
27 | #include <assert.h> | |
28 | #include <sys/mman.h> | |
29 | #include <string.h> | |
30 | ||
31 | #include "blktrace.h" | |
32 | ||
33 | #define DEF_LEN (16 * 1024 * 1024) | |
34 | ||
35 | static int fd; | |
36 | static void *cur_map = MAP_FAILED; | |
37 | static off_t cur_min, cur, cur_max, total_size; | |
38 | static size_t len; | |
39 | static struct blk_io_trace *next_t; | |
40 | static long pgsz; | |
41 | ||
42 | int data_is_native = -1; | |
43 | ||
44 | static inline size_t min_len(size_t a, size_t b) { return a < b ? a : b; } | |
45 | ||
46 | static inline size_t convert_to_cpu(struct blk_io_trace *t, | |
47 | struct blk_io_trace *tp, | |
48 | void **pdu) | |
49 | { | |
50 | if (data_is_native == -1) | |
51 | check_data_endianness(t->magic); | |
52 | ||
53 | if (data_is_native) | |
54 | memcpy(tp, t, sizeof(*tp)); | |
55 | else { | |
56 | tp->magic = be32_to_cpu(t->magic); | |
57 | tp->sequence = be32_to_cpu(t->sequence); | |
58 | tp->time = be64_to_cpu(t->time); | |
59 | tp->sector = be64_to_cpu(t->sector); | |
60 | tp->bytes = be32_to_cpu(t->bytes); | |
61 | tp->action = be32_to_cpu(t->action); | |
62 | tp->pid = be32_to_cpu(t->pid); | |
63 | tp->device = be32_to_cpu(t->device); | |
64 | tp->cpu = be16_to_cpu(t->cpu); | |
65 | tp->error = be16_to_cpu(t->error); | |
66 | tp->pdu_len = be16_to_cpu(t->pdu_len); | |
67 | } | |
68 | ||
69 | assert(CHECK_MAGIC(tp)); | |
70 | assert((tp->magic & 0xff) == SUPPORTED_VERSION); | |
71 | ||
72 | if (tp->pdu_len) { | |
73 | *pdu = malloc(tp->pdu_len); | |
74 | memcpy(*pdu, t+1, tp->pdu_len); | |
75 | } | |
76 | else | |
77 | *pdu = NULL; | |
78 | ||
79 | return sizeof(*tp) + tp->pdu_len; | |
80 | } | |
81 | ||
82 | static int move_map(void) | |
83 | { | |
84 | if (cur_map != MAP_FAILED) | |
85 | munmap(cur_map, len); | |
86 | ||
87 | cur_min = (cur & ~(pgsz-1)); | |
88 | len = min_len(DEF_LEN, total_size - cur_min); | |
89 | if (len < sizeof(*next_t)) | |
90 | return 0; | |
91 | ||
92 | cur_map = mmap(NULL, len, PROT_READ, MAP_SHARED, fd, | |
93 | cur_min); | |
94 | if (cur_map == MAP_FAILED) { | |
95 | perror("mmap"); | |
96 | exit(1); | |
97 | } | |
98 | ||
99 | cur_max = cur_min + len; | |
100 | return (cur < cur_max); | |
101 | } | |
102 | ||
103 | void setup_ifile(char *fname) | |
104 | { | |
105 | struct stat buf; | |
106 | ||
107 | pgsz = sysconf(_SC_PAGESIZE); | |
108 | ||
109 | fd = open(fname, O_RDONLY); | |
110 | if (fd < 0) { | |
111 | perror(fname); | |
112 | exit(1); | |
113 | } | |
114 | if (fstat(fd, &buf) < 0) { | |
115 | perror(fname); | |
116 | exit(1); | |
117 | } | |
118 | total_size = buf.st_size; | |
119 | ||
120 | if (!move_map()) | |
121 | exit(0); | |
122 | } | |
123 | ||
124 | void cleanup_ifile(void) | |
125 | { | |
126 | if (cur_map != MAP_FAILED) | |
127 | munmap(cur_map, len); | |
128 | close(fd); | |
129 | } | |
130 | ||
131 | int next_trace(struct blk_io_trace *t, void **pdu) | |
132 | { | |
133 | size_t this_len; | |
134 | ||
135 | if ((cur + 512) > cur_max) | |
136 | if (!move_map()) | |
137 | return 0; | |
138 | ||
139 | next_t = cur_map + (cur - cur_min); | |
140 | this_len = convert_to_cpu(next_t, t, pdu); | |
141 | cur += this_len; | |
142 | ||
143 | return 1; | |
144 | } |