diskutil.c revision ccb0fa24f0ff37f9270754ea5a1b66de9fd7053e 
1#include <stdio.h>
2#include <string.h>
3#include <sys/time.h>
4#include <sys/types.h>
5#include <sys/stat.h>
6#include <dirent.h>
7#include <libgen.h>
8#include <math.h>
9
10#include "fio.h"
11
12static int last_majdev, last_mindev;
13
14static struct list_head disk_list = LIST_HEAD_INIT(disk_list);
15
16static int get_io_ticks(struct disk_util *du, struct disk_util_stat *dus)
17{
18	unsigned in_flight;
19	char line[256];
20	FILE *f;
21	char *p;
22	int ret;
23
24	dprint(FD_DISKUTIL, "open stat file: %s\n", du->path);
25
26	f = fopen(du->path, "r");
27	if (!f)
28		return 1;
29
30	p = fgets(line, sizeof(line), f);
31	if (!p) {
32		fclose(f);
33		return 1;
34	}
35
36	dprint(FD_DISKUTIL, "%s: %s", du->path, p);
37
38	ret = sscanf(p, "%u %u %llu %u %u %u %llu %u %u %u %u\n", &dus->ios[0],
39					&dus->merges[0], &dus->sectors[0],
40					&dus->ticks[0], &dus->ios[1],
41					&dus->merges[1], &dus->sectors[1],
42					&dus->ticks[1], &in_flight,
43					&dus->io_ticks, &dus->time_in_queue);
44	fclose(f);
45	dprint(FD_DISKUTIL, "%s: stat read ok? %d\n", du->path, ret == 1);
46	return ret != 11;
47}
48
49static void update_io_tick_disk(struct disk_util *du)
50{
51	struct disk_util_stat __dus, *dus, *ldus;
52	struct timeval t;
53
54	if (get_io_ticks(du, &__dus))
55		return;
56
57	dus = &du->dus;
58	ldus = &du->last_dus;
59
60	dus->sectors[0] += (__dus.sectors[0] - ldus->sectors[0]);
61	dus->sectors[1] += (__dus.sectors[1] - ldus->sectors[1]);
62	dus->ios[0] += (__dus.ios[0] - ldus->ios[0]);
63	dus->ios[1] += (__dus.ios[1] - ldus->ios[1]);
64	dus->merges[0] += (__dus.merges[0] - ldus->merges[0]);
65	dus->merges[1] += (__dus.merges[1] - ldus->merges[1]);
66	dus->ticks[0] += (__dus.ticks[0] - ldus->ticks[0]);
67	dus->ticks[1] += (__dus.ticks[1] - ldus->ticks[1]);
68	dus->io_ticks += (__dus.io_ticks - ldus->io_ticks);
69	dus->time_in_queue += (__dus.time_in_queue - ldus->time_in_queue);
70
71	fio_gettime(&t, NULL);
72	du->msec += mtime_since(&du->time, &t);
73	memcpy(&du->time, &t, sizeof(t));
74	memcpy(ldus, &__dus, sizeof(__dus));
75}
76
77void update_io_ticks(void)
78{
79	struct list_head *entry;
80	struct disk_util *du;
81
82	dprint(FD_DISKUTIL, "update io ticks\n");
83
84	list_for_each(entry, &disk_list) {
85		du = list_entry(entry, struct disk_util, list);
86		update_io_tick_disk(du);
87	}
88}
89
90static struct disk_util *disk_util_exists(int major, int minor)
91{
92	struct list_head *entry;
93	struct disk_util *du;
94
95	list_for_each(entry, &disk_list) {
96		du = list_entry(entry, struct disk_util, list);
97
98		if (major == du->major && minor == du->minor)
99			return du;
100	}
101
102	return NULL;
103}
104
105static void disk_util_add(int majdev, int mindev, char *path)
106{
107	struct disk_util *du, *__du;
108	struct list_head *entry;
109
110	dprint(FD_DISKUTIL, "add maj/min %d/%d: %s\n", majdev, mindev, path);
111
112	du = malloc(sizeof(*du));
113	memset(du, 0, sizeof(*du));
114	INIT_LIST_HEAD(&du->list);
115	sprintf(du->path, "%s/stat", path);
116	du->name = strdup(basename(path));
117	du->sysfs_root = path;
118	du->major = majdev;
119	du->minor = mindev;
120
121	list_for_each(entry, &disk_list) {
122		__du = list_entry(entry, struct disk_util, list);
123
124		dprint(FD_DISKUTIL, "found %s in list\n", __du->name);
125
126		if (!strcmp(du->name, __du->name)) {
127			free(du->name);
128			free(du);
129			return;
130		}
131	}
132
133	dprint(FD_DISKUTIL, "add %s to list\n", du->name);
134
135	fio_gettime(&du->time, NULL);
136	get_io_ticks(du, &du->last_dus);
137
138	list_add_tail(&du->list, &disk_list);
139}
140
141static int check_dev_match(int majdev, int mindev, char *path)
142{
143	int major, minor;
144	char line[256], *p;
145	FILE *f;
146
147	f = fopen(path, "r");
148	if (!f) {
149		perror("open path");
150		return 1;
151	}
152
153	p = fgets(line, sizeof(line), f);
154	if (!p) {
155		fclose(f);
156		return 1;
157	}
158
159	if (sscanf(p, "%u:%u", &major, &minor) != 2) {
160		fclose(f);
161		return 1;
162	}
163
164	if (majdev == major && mindev == minor) {
165		fclose(f);
166		return 0;
167	}
168
169	fclose(f);
170	return 1;
171}
172
173static int find_block_dir(int majdev, int mindev, char *path)
174{
175	struct dirent *dir;
176	struct stat st;
177	int found = 0;
178	DIR *D;
179
180	D = opendir(path);
181	if (!D)
182		return 0;
183
184	while ((dir = readdir(D)) != NULL) {
185		char full_path[256];
186
187		if (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, ".."))
188			continue;
189
190		sprintf(full_path, "%s/%s", path, dir->d_name);
191
192		if (!strcmp(dir->d_name, "dev")) {
193			if (!check_dev_match(majdev, mindev, full_path)) {
194				found = 1;
195				break;
196			}
197		}
198
199		if (lstat(full_path, &st) == -1) {
200			perror("stat");
201			break;
202		}
203
204		if (!S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode))
205			continue;
206
207		found = find_block_dir(majdev, mindev, full_path);
208		if (found) {
209			strcpy(path, full_path);
210			break;
211		}
212	}
213
214	closedir(D);
215	return found;
216}
217
218static void __init_disk_util(struct thread_data *td, struct fio_file *f)
219{
220	struct stat st;
221	char foo[PATH_MAX], tmp[PATH_MAX];
222	struct disk_util *du;
223	int mindev, majdev;
224	char *p;
225
226	if (!lstat(f->file_name, &st)) {
227		if (S_ISBLK(st.st_mode)) {
228			majdev = major(st.st_rdev);
229			mindev = minor(st.st_rdev);
230		} else if (S_ISCHR(st.st_mode)) {
231			majdev = major(st.st_rdev);
232			mindev = minor(st.st_rdev);
233			if (fio_lookup_raw(st.st_rdev, &majdev, &mindev))
234				return;
235		} else if (S_ISFIFO(st.st_mode))
236			return;
237		else {
238			majdev = major(st.st_dev);
239			mindev = minor(st.st_dev);
240		}
241	} else {
242		/*
243		 * must be a file, open "." in that path
244		 */
245		strncpy(foo, f->file_name, PATH_MAX - 1);
246		p = dirname(foo);
247		if (stat(p, &st)) {
248			perror("disk util stat");
249			return;
250		}
251
252		majdev = major(st.st_dev);
253		mindev = minor(st.st_dev);
254	}
255
256	dprint(FD_DISKUTIL, "%s belongs to maj/min %d/%d\n", f->file_name,
257							majdev, mindev);
258
259	du = disk_util_exists(majdev, mindev);
260	if (du) {
261		if (td->o.ioscheduler && !td->sysfs_root)
262			td->sysfs_root = strdup(du->sysfs_root);
263
264		return;
265	}
266
267	/*
268	 * for an fs without a device, we will repeatedly stat through
269	 * sysfs which can take oodles of time for thousands of files. so
270	 * cache the last lookup and compare with that before going through
271	 * everything again.
272	 */
273	if (mindev == last_mindev && majdev == last_majdev)
274		return;
275
276	last_mindev = mindev;
277	last_majdev = majdev;
278
279	sprintf(foo, "/sys/block");
280	if (!find_block_dir(majdev, mindev, foo))
281		return;
282
283	/*
284	 * If there's a ../queue/ directory there, we are inside a partition.
285	 * Check if that is the case and jump back. For loop/md/dm etc we
286	 * are already in the right spot.
287	 */
288	sprintf(tmp, "%s/../queue", foo);
289	if (!stat(tmp, &st)) {
290		p = dirname(foo);
291		sprintf(tmp, "%s/queue", p);
292		if (stat(tmp, &st)) {
293			log_err("unknown sysfs layout\n");
294			return;
295		}
296		strncpy(tmp, p, PATH_MAX - 1);
297		sprintf(foo, "%s", tmp);
298	}
299
300	if (td->o.ioscheduler && !td->sysfs_root)
301		td->sysfs_root = strdup(foo);
302
303	disk_util_add(majdev, mindev, foo);
304}
305
306void init_disk_util(struct thread_data *td)
307{
308	struct fio_file *f;
309	unsigned int i;
310
311	if (!td->o.do_disk_util ||
312	    (td->io_ops->flags & (FIO_DISKLESSIO | FIO_NODISKUTIL)))
313		return;
314
315	for_each_file(td, f, i)
316		__init_disk_util(td, f);
317}
318
319void show_disk_util(void)
320{
321	struct disk_util_stat *dus;
322	struct list_head *entry, *next;
323	struct disk_util *du;
324	double util;
325
326	if (list_empty(&disk_list))
327		return;
328
329	log_info("\nDisk stats (read/write):\n");
330
331	list_for_each(entry, &disk_list) {
332		du = list_entry(entry, struct disk_util, list);
333		dus = &du->dus;
334
335		util = (double) 100 * du->dus.io_ticks / (double) du->msec;
336		if (util > 100.0)
337			util = 100.0;
338
339		log_info("  %s: ios=%u/%u, merge=%u/%u, ticks=%u/%u, "
340			 "in_queue=%u, util=%3.2f%%\n", du->name,
341						dus->ios[0], dus->ios[1],
342						dus->merges[0], dus->merges[1],
343						dus->ticks[0], dus->ticks[1],
344						dus->time_in_queue, util);
345	}
346
347	/*
348	 * now free the list
349	 */
350	list_for_each_safe(entry, next, &disk_list) {
351		list_del(entry);
352		du = list_entry(entry, struct disk_util, list);
353		free(du->name);
354		free(du);
355	}
356}
357