2 * blktrace output analysis: generate a timeline & gather statistics
4 * Copyright (C) 2006 Alan D. Brunelle <Alan.Brunelle@hp.com>
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.
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.
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
24 #include <sys/types.h>
33 #define DEF_LEN (16 * 1024 * 1024)
36 static void *cur_map = MAP_FAILED;
37 static off_t cur_min, cur, cur_max, total_size;
39 static struct blk_io_trace *next_t;
42 int data_is_native = -1;
44 static inline size_t min_len(size_t a, size_t b) { return a < b ? a : b; }
46 static inline size_t convert_to_cpu(struct blk_io_trace *t,
47 struct blk_io_trace *tp,
50 if (data_is_native == -1)
51 check_data_endianness(t->magic);
54 memcpy(tp, t, sizeof(*tp));
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);
69 assert(CHECK_MAGIC(tp));
70 assert((tp->magic & 0xff) == SUPPORTED_VERSION);
73 *pdu = malloc(tp->pdu_len);
74 memcpy(*pdu, t+1, tp->pdu_len);
79 return sizeof(*tp) + tp->pdu_len;
82 static int move_map(void)
84 if (cur_map != MAP_FAILED)
87 cur_min = (cur & ~(pgsz-1));
88 len = min_len(DEF_LEN, total_size - cur_min);
89 if (len < sizeof(*next_t))
92 cur_map = mmap(NULL, len, PROT_READ, MAP_SHARED, fd,
94 if (cur_map == MAP_FAILED) {
99 cur_max = cur_min + len;
100 return (cur < cur_max);
103 void setup_ifile(char *fname)
107 pgsz = sysconf(_SC_PAGESIZE);
109 fd = open(fname, O_RDONLY);
114 if (fstat(fd, &buf) < 0) {
118 total_size = buf.st_size;
124 void cleanup_ifile(void)
126 if (cur_map != MAP_FAILED)
127 munmap(cur_map, len);
131 int next_trace(struct blk_io_trace *t, void **pdu)
135 if ((cur + 512) > cur_max)
139 next_t = cur_map + (cur - cur_min);
140 this_len = convert_to_cpu(next_t, t, pdu);