Commit | Line | Data |
---|---|---|
fb7b71a3 JA |
1 | /* |
2 | * blktrace support code for fio | |
3 | */ | |
4 | #include <stdio.h> | |
5 | #include <stdlib.h> | |
8c1fdf04 | 6 | |
fb7b71a3 JA |
7 | #include "list.h" |
8 | #include "fio.h" | |
9 | #include "blktrace_api.h" | |
10 | ||
e2887563 JA |
11 | #define TRACE_FIFO_SIZE (sizeof(struct blk_io_trace) * 1000) |
12 | ||
13 | /* | |
14 | * fifo refill frontend, to avoid reading data in trace sized bites | |
15 | */ | |
16 | static int refill_fifo(struct thread_data *td, struct fifo *fifo, int fd) | |
17 | { | |
18 | char buf[TRACE_FIFO_SIZE]; | |
19 | unsigned int total, left; | |
20 | void *ptr; | |
21 | int ret; | |
22 | ||
23 | total = 0; | |
24 | ptr = buf; | |
25 | while (total < TRACE_FIFO_SIZE) { | |
26 | left = TRACE_FIFO_SIZE - total; | |
27 | ||
28 | ret = read(fd, ptr, left); | |
29 | if (ret < 0) { | |
30 | td_verror(td, errno, "read blktrace file"); | |
31 | return -1; | |
32 | } else if (!ret) | |
33 | break; | |
34 | ||
35 | fifo_put(fifo, ptr, ret); | |
36 | ptr += ret; | |
37 | total += ret; | |
38 | } | |
39 | ||
40 | return 0; | |
41 | } | |
42 | ||
43 | /* | |
44 | * Retrieve 'len' bytes from the fifo, refilling if necessary. | |
45 | */ | |
46 | static int trace_fifo_get(struct thread_data *td, struct fifo *fifo, int fd, | |
47 | void *buf, unsigned int len) | |
48 | { | |
49 | int ret; | |
50 | ||
51 | if (fifo_len(fifo) >= len) | |
52 | return fifo_get(fifo, buf, len); | |
53 | ||
54 | ret = refill_fifo(td, fifo, fd); | |
55 | if (ret < 0) | |
56 | return ret; | |
57 | ||
58 | if (fifo_len(fifo) < len) | |
59 | return 0; | |
60 | ||
61 | return fifo_get(fifo, buf, len); | |
62 | } | |
63 | ||
8c1fdf04 JA |
64 | /* |
65 | * Just discard the pdu by seeking past it. | |
66 | */ | |
fb7b71a3 JA |
67 | static int discard_pdu(int fd, struct blk_io_trace *t) |
68 | { | |
69 | if (t->pdu_len == 0) | |
70 | return 0; | |
71 | ||
72 | if (lseek(fd, t->pdu_len, SEEK_CUR) < 0) | |
73 | return errno; | |
74 | ||
75 | return 0; | |
76 | } | |
77 | ||
8c1fdf04 JA |
78 | /* |
79 | * Check if this is a blktrace binary data file. We read a single trace | |
80 | * into memory and check for the magic signature. | |
81 | */ | |
fb7b71a3 JA |
82 | int is_blktrace(const char *filename) |
83 | { | |
84 | struct blk_io_trace t; | |
85 | int fd, ret; | |
86 | ||
87 | fd = open(filename, O_RDONLY); | |
88 | if (fd < 0) { | |
89 | perror("open blktrace"); | |
90 | return 0; | |
91 | } | |
92 | ||
93 | ret = read(fd, &t, sizeof(t)); | |
94 | close(fd); | |
95 | ||
96 | if (ret < 0) { | |
97 | perror("read blktrace"); | |
98 | return 0; | |
99 | } else if (ret != sizeof(t)) { | |
100 | log_err("fio: short read on blktrace file\n"); | |
101 | return 0; | |
102 | } | |
103 | ||
104 | if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC) | |
105 | return 1; | |
106 | ||
107 | return 0; | |
108 | } | |
109 | ||
8c1fdf04 JA |
110 | /* |
111 | * Store blk_io_trace data in an ipo for later retrieval. | |
112 | */ | |
fdefd987 | 113 | static void store_ipo(struct thread_data *td, unsigned long long offset, |
8c1fdf04 | 114 | unsigned int bytes, int rw, unsigned long long ttime) |
fdefd987 JA |
115 | { |
116 | struct io_piece *ipo = malloc(sizeof(*ipo)); | |
117 | ||
118 | memset(ipo, 0, sizeof(*ipo)); | |
119 | INIT_LIST_HEAD(&ipo->list); | |
a2eea81b JA |
120 | /* |
121 | * the 512 is wrong here, it should be the hardware sector size... | |
122 | */ | |
123 | ipo->offset = offset * 512; | |
fdefd987 | 124 | ipo->len = bytes; |
8c1fdf04 | 125 | ipo->delay = ttime / 1000; |
fdefd987 JA |
126 | if (rw) |
127 | ipo->ddir = DDIR_WRITE; | |
128 | else | |
129 | ipo->ddir = DDIR_READ; | |
130 | ||
131 | list_add_tail(&ipo->list, &td->io_log_list); | |
132 | } | |
133 | ||
8c1fdf04 JA |
134 | /* |
135 | * We only care for queue traces, most of the others are side effects | |
136 | * due to internal workings of the block layer. | |
137 | */ | |
138 | static void handle_trace(struct thread_data *td, struct blk_io_trace *t, | |
d84f8d49 JA |
139 | unsigned long long ttime, unsigned long *ios, |
140 | unsigned int *bs) | |
fb7b71a3 | 141 | { |
fdefd987 JA |
142 | int rw; |
143 | ||
144 | if ((t->action & 0xffff) != __BLK_TA_QUEUE) | |
145 | return; | |
a2eea81b JA |
146 | if (t->action & BLK_TC_ACT(BLK_TC_PC)) |
147 | return; | |
148 | ||
149 | /* | |
150 | * should not happen, need to look into that... | |
151 | */ | |
152 | if (!t->bytes) | |
153 | return; | |
fdefd987 | 154 | |
e7a7d70b | 155 | rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0; |
d84f8d49 JA |
156 | |
157 | if (t->bytes > bs[rw]) | |
158 | bs[rw] = t->bytes; | |
159 | ||
8c1fdf04 | 160 | ios[rw]++; |
6df8adaa | 161 | td->o.size += t->bytes; |
8c1fdf04 | 162 | store_ipo(td, t->sector, t->bytes, rw, ttime); |
fb7b71a3 JA |
163 | } |
164 | ||
8c1fdf04 JA |
165 | /* |
166 | * Load a blktrace file by reading all the blk_io_trace entries, and storing | |
167 | * them as io_pieces like the fio text version would do. | |
168 | */ | |
fb7b71a3 JA |
169 | int load_blktrace(struct thread_data *td, const char *filename) |
170 | { | |
a61eddec | 171 | unsigned long long ttime, delay; |
fb7b71a3 | 172 | struct blk_io_trace t; |
8c1fdf04 | 173 | unsigned long ios[2]; |
a61eddec | 174 | unsigned int cpu; |
d84f8d49 | 175 | unsigned int rw_bs[2]; |
e2887563 | 176 | struct fifo *fifo; |
fb7b71a3 JA |
177 | int fd; |
178 | ||
179 | fd = open(filename, O_RDONLY); | |
180 | if (fd < 0) { | |
181 | td_verror(td, errno, "open blktrace file"); | |
182 | return 1; | |
183 | } | |
184 | ||
e2887563 JA |
185 | fifo = fifo_alloc(TRACE_FIFO_SIZE); |
186 | ||
6df8adaa JA |
187 | td->o.size = 0; |
188 | ||
a61eddec | 189 | cpu = 0; |
d84f8d49 JA |
190 | ttime = 0; |
191 | ios[0] = ios[1] = 0; | |
192 | rw_bs[0] = rw_bs[1] = 0; | |
fb7b71a3 | 193 | do { |
e2887563 | 194 | int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t)); |
fb7b71a3 | 195 | |
e2887563 | 196 | if (ret < 0) |
8c1fdf04 | 197 | goto err; |
e2887563 JA |
198 | else if (!ret) |
199 | break; | |
200 | else if (ret < (int) sizeof(t)) { | |
201 | log_err("fio: short fifo get\n"); | |
fb7b71a3 | 202 | break; |
fb7b71a3 JA |
203 | } |
204 | ||
205 | if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) { | |
206 | log_err("fio: bad magic in blktrace data\n"); | |
8c1fdf04 | 207 | goto err; |
fb7b71a3 JA |
208 | } |
209 | if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) { | |
210 | log_err("fio: bad blktrace version %d\n", t.magic & 0xff); | |
8c1fdf04 | 211 | goto err; |
fb7b71a3 JA |
212 | } |
213 | ret = discard_pdu(fd, &t); | |
214 | if (ret) { | |
215 | td_verror(td, ret, "blktrace lseek"); | |
8c1fdf04 | 216 | goto err; |
fb7b71a3 | 217 | } |
a61eddec | 218 | if (!ttime) { |
8c1fdf04 | 219 | ttime = t.time; |
a61eddec JA |
220 | cpu = t.cpu; |
221 | } | |
222 | delay = 0; | |
223 | if (cpu == t.cpu) | |
224 | delay = t.time - ttime; | |
d84f8d49 | 225 | handle_trace(td, &t, delay, ios, rw_bs); |
8c1fdf04 | 226 | ttime = t.time; |
a61eddec | 227 | cpu = t.cpu; |
fb7b71a3 JA |
228 | } while (1); |
229 | ||
38470f85 | 230 | fifo_free(fifo); |
fb7b71a3 | 231 | close(fd); |
8c1fdf04 JA |
232 | |
233 | if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) { | |
234 | log_err("fio: found no ios in blktrace data\n"); | |
235 | return 1; | |
d84f8d49 | 236 | } else if (ios[DDIR_READ] && !ios[DDIR_READ]) { |
8c1fdf04 | 237 | td->o.td_ddir = TD_DDIR_READ; |
d84f8d49 JA |
238 | td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ]; |
239 | } else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) { | |
8c1fdf04 | 240 | td->o.td_ddir = TD_DDIR_WRITE; |
d84f8d49 JA |
241 | td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE]; |
242 | } else { | |
8c1fdf04 | 243 | td->o.td_ddir = TD_DDIR_RW; |
d84f8d49 JA |
244 | td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ]; |
245 | td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE]; | |
246 | } | |
8c1fdf04 JA |
247 | |
248 | /* | |
249 | * We need to do direct/raw ios to the device, to avoid getting | |
250 | * read-ahead in our way. | |
251 | */ | |
252 | td->o.odirect = 1; | |
253 | ||
fb7b71a3 | 254 | return 0; |
8c1fdf04 JA |
255 | err: |
256 | close(fd); | |
38470f85 | 257 | fifo_free(fifo); |
8c1fdf04 | 258 | return 1; |
fb7b71a3 | 259 | } |