xref: /netbsd-src/sys/kern/subr_iostat.c (revision fad4c9f71477ae11cea2ee75ec82151ac770a534)
1 /*	$NetBSD: subr_iostat.c,v 1.10 2006/06/07 22:33:40 kardel Exp $	*/
2 /*	NetBSD: subr_disk.c,v 1.69 2005/05/29 22:24:15 christos Exp	*/
3 
4 /*-
5  * Copyright (c) 1996, 1997, 1999, 2000 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
10  * NASA Ames Research Center.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the NetBSD
23  *	Foundation, Inc. and its contributors.
24  * 4. Neither the name of The NetBSD Foundation nor the names of its
25  *    contributors may be used to endorse or promote products derived
26  *    from this software without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
29  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
30  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
31  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
32  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38  * POSSIBILITY OF SUCH DAMAGE.
39  */
40 
41 /*
42  * Copyright (c) 1982, 1986, 1988, 1993
43  *	The Regents of the University of California.  All rights reserved.
44  * (c) UNIX System Laboratories, Inc.
45  * All or some portions of this file are derived from material licensed
46  * to the University of California by American Telephone and Telegraph
47  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
48  * the permission of UNIX System Laboratories, Inc.
49  *
50  * Redistribution and use in source and binary forms, with or without
51  * modification, are permitted provided that the following conditions
52  * are met:
53  * 1. Redistributions of source code must retain the above copyright
54  *    notice, this list of conditions and the following disclaimer.
55  * 2. Redistributions in binary form must reproduce the above copyright
56  *    notice, this list of conditions and the following disclaimer in the
57  *    documentation and/or other materials provided with the distribution.
58  * 3. Neither the name of the University nor the names of its contributors
59  *    may be used to endorse or promote products derived from this software
60  *    without specific prior written permission.
61  *
62  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
63  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
64  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
65  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
66  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
67  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
68  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
69  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
70  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
71  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
72  * SUCH DAMAGE.
73  *
74  *	@(#)ufs_disksubr.c	8.5 (Berkeley) 1/21/94
75  */
76 
77 #include <sys/cdefs.h>
78 __KERNEL_RCSID(0, "$NetBSD: subr_iostat.c,v 1.10 2006/06/07 22:33:40 kardel Exp $");
79 
80 #include "opt_compat_netbsd.h"
81 
82 #include <sys/param.h>
83 #include <sys/kernel.h>
84 #include <sys/malloc.h>
85 #include <sys/iostat.h>
86 #include <sys/sysctl.h>
87 
88 /*
89  * Function prototypes for sysctl nodes
90  */
91 static int	sysctl_hw_disknames(SYSCTLFN_PROTO);
92 static int	sysctl_hw_iostatnames(SYSCTLFN_PROTO);
93 static int	sysctl_hw_iostats(SYSCTLFN_PROTO);
94 
95 static int
96 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp,
97 		u_int namelen);
98 
99 /*
100  * A global list of all drives attached to the system.  May grow or
101  * shrink over time.
102  */
103 struct iostatlist_head iostatlist = TAILQ_HEAD_INITIALIZER(iostatlist);
104 int iostat_count;		/* number of drives in global drivelist */
105 struct simplelock iostatlist_slock = SIMPLELOCK_INITIALIZER;
106 
107 /*
108  * Searches the iostatlist for the iostat corresponding to the
109  * name provided.
110  */
111 struct io_stats *
112 iostat_find(const char *name)
113 {
114 	struct io_stats *iostatp;
115 
116 	KASSERT(name != NULL);
117 
118 	simple_lock(&iostatlist_slock);
119 	TAILQ_FOREACH(iostatp, &iostatlist, io_link) {
120 		if (strcmp(iostatp->io_name, name) == 0) {
121 			break;
122 		}
123 	}
124 	simple_unlock(&iostatlist_slock);
125 
126 	return iostatp;
127 }
128 
129 /*
130  * Allocate and initialise memory for the i/o statistics.
131  */
132 struct io_stats *
133 iostat_alloc(int32_t type)
134 {
135 	struct io_stats *stats;
136 
137 	stats = malloc(sizeof(struct io_stats), M_DEVBUF, M_WAITOK|M_ZERO);
138 	if (stats == NULL)
139 		panic("iostat_alloc: cannot allocate memory for stats buffer");
140 
141 	stats->io_type = type;
142 
143 	/*
144 	 * Set the attached timestamp.
145 	 */
146 	getmicrouptime(&stats->io_attachtime);
147 
148 	/*
149 	 * Link into the drivelist.
150 	 */
151 	simple_lock(&iostatlist_slock);
152 	TAILQ_INSERT_TAIL(&iostatlist, stats, io_link);
153 	iostat_count++;
154 	simple_unlock(&iostatlist_slock);
155 
156 	return stats;
157 }
158 
159 /*
160  * Remove i/o from stats collection.
161  */
162 void
163 iostat_free(struct io_stats *stats)
164 {
165 
166 	/*
167 	 * Remove from the iostat list.
168 	 */
169 	if (iostat_count == 0)
170 		panic("iostat_free: iostat_count == 0");
171 	simple_lock(&iostatlist_slock);
172 	TAILQ_REMOVE(&iostatlist, stats, io_link);
173 	iostat_count--;
174 	simple_unlock(&iostatlist_slock);
175 	free(stats, M_DEVBUF);
176 }
177 
178 /*
179  * Increment a iostat busy counter.  If the counter is going from
180  * 0 to 1, set the timestamp.
181  */
182 void
183 iostat_busy(struct io_stats *stats)
184 {
185 
186 	if (stats->io_busy++ == 0)
187 		getmicrouptime(&stats->io_timestamp);
188 }
189 
190 /*
191  * Decrement a iostat busy counter, increment the byte count, total busy
192  * time, and reset the timestamp.
193  */
194 void
195 iostat_unbusy(struct io_stats *stats, long bcount, int read)
196 {
197 	struct timeval dv_time, diff_time;
198 
199 	if (stats->io_busy-- == 0) {
200 		printf("%s: busy < 0\n", stats->io_name);
201 		panic("iostat_unbusy");
202 	}
203 
204 	getmicrouptime(&dv_time);
205 
206 	timersub(&dv_time, &stats->io_timestamp, &diff_time);
207 	timeradd(&stats->io_time, &diff_time, &stats->io_time);
208 
209 	stats->io_timestamp = dv_time;
210 	if (bcount > 0) {
211 		if (read) {
212 			stats->io_rbytes += bcount;
213 			stats->io_rxfer++;
214 		} else {
215 			stats->io_wbytes += bcount;
216 			stats->io_wxfer++;
217 		}
218 	}
219 }
220 
221 /*
222  * Increment the seek counter.  This does look almost redundant but it
223  * abstracts the stats gathering.
224  */
225 void
226 iostat_seek(struct io_stats *stats)
227 {
228 
229 	stats->io_seek++;
230 }
231 
232 static int
233 sysctl_hw_disknames(SYSCTLFN_ARGS)
234 {
235 
236 	return iostati_getnames(1, oldp, oldlenp, newp, namelen);
237 }
238 
239 static int
240 sysctl_hw_iostatnames(SYSCTLFN_ARGS)
241 {
242 
243 	return iostati_getnames(0, oldp, oldlenp, newp, namelen);
244 }
245 
246 static int
247 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp,
248 		 u_int namelen)
249 {
250 	char bf[IOSTATNAMELEN + 1];
251 	char *where = oldp;
252 	struct io_stats *stats;
253 	size_t needed, left, slen;
254 	int error, first;
255 
256 	if (newp != NULL)
257 		return (EPERM);
258 	if (namelen != 0)
259 		return (EINVAL);
260 
261 	first = 1;
262 	error = 0;
263 	needed = 0;
264 	left = *oldlenp;
265 
266 	simple_lock(&iostatlist_slock);
267 	for (stats = TAILQ_FIRST(&iostatlist); stats != NULL;
268 	    stats = TAILQ_NEXT(stats, io_link)) {
269 		if ((disk_only == 1) && (stats->io_type != IOSTAT_DISK))
270 			continue;
271 
272 		if (where == NULL)
273 			needed += strlen(stats->io_name) + 1;
274 		else {
275 			memset(bf, 0, sizeof(bf));
276 			if (first) {
277 				strncpy(bf, stats->io_name, sizeof(bf));
278 				first = 0;
279 			} else {
280 				bf[0] = ' ';
281 				strncpy(bf + 1, stats->io_name,
282 				    sizeof(bf) - 1);
283 			}
284 			bf[IOSTATNAMELEN] = '\0';
285 			slen = strlen(bf);
286 			if (left < slen + 1)
287 				break;
288 			/* +1 to copy out the trailing NUL byte */
289 			error = copyout(bf, where, slen + 1);
290 			if (error)
291 				break;
292 			where += slen;
293 			needed += slen;
294 			left -= slen;
295 		}
296 	}
297 	simple_unlock(&iostatlist_slock);
298 	*oldlenp = needed;
299 	return (error);
300 }
301 
302 static int
303 sysctl_hw_iostats(SYSCTLFN_ARGS)
304 {
305 	struct io_sysctl sdrive;
306 	struct io_stats *stats;
307 	char *where = oldp;
308 	size_t tocopy, left;
309 	int error;
310 
311 	if (newp != NULL)
312 		return (EPERM);
313 
314 	/*
315 	 * The original hw.diskstats call was broken and did not require
316 	 * the userland to pass in it's size of struct disk_sysctl.  This
317 	 * was fixed after NetBSD 1.6 was released, and any applications
318 	 * that do not pass in the size are given an error only, unless
319 	 * we care about 1.6 compatibility.
320 	 */
321 	if (namelen == 0)
322 #ifdef COMPAT_16
323 		tocopy = offsetof(struct io_sysctl, busy);
324 #else
325 		return (EINVAL);
326 #endif
327 	else
328 		tocopy = name[0];
329 
330 	if (where == NULL) {
331 		*oldlenp = iostat_count * tocopy;
332 		return (0);
333 	}
334 
335 	error = 0;
336 	left = *oldlenp;
337 	memset(&sdrive, 0, sizeof(sdrive));
338 	*oldlenp = 0;
339 
340 	simple_lock(&iostatlist_slock);
341 	TAILQ_FOREACH(stats, &iostatlist, io_link) {
342 		if (left < tocopy)
343 			break;
344 		strncpy(sdrive.name, stats->io_name, sizeof(sdrive.name));
345 		sdrive.xfer = stats->io_rxfer + stats->io_wxfer;
346 		sdrive.rxfer = stats->io_rxfer;
347 		sdrive.wxfer = stats->io_wxfer;
348 		sdrive.seek = stats->io_seek;
349 		sdrive.bytes = stats->io_rbytes + stats->io_wbytes;
350 		sdrive.rbytes = stats->io_rbytes;
351 		sdrive.wbytes = stats->io_wbytes;
352 		sdrive.attachtime_sec = stats->io_attachtime.tv_sec;
353 		sdrive.attachtime_usec = stats->io_attachtime.tv_usec;
354 		sdrive.timestamp_sec = stats->io_timestamp.tv_sec;
355 		sdrive.timestamp_usec = stats->io_timestamp.tv_usec;
356 		sdrive.time_sec = stats->io_time.tv_sec;
357 		sdrive.time_usec = stats->io_time.tv_usec;
358 		sdrive.busy = stats->io_busy;
359 
360 		error = copyout(&sdrive, where, min(tocopy, sizeof(sdrive)));
361 		if (error)
362 			break;
363 		where += tocopy;
364 		*oldlenp += tocopy;
365 		left -= tocopy;
366 	}
367 	simple_unlock(&iostatlist_slock);
368 	return (error);
369 }
370 
371 SYSCTL_SETUP(sysctl_io_stats_setup, "sysctl i/o stats setup")
372 {
373 
374 	sysctl_createv(clog, 0, NULL, NULL,
375 		       CTLFLAG_PERMANENT,
376 		       CTLTYPE_STRING, "disknames",
377 		       SYSCTL_DESCR("List of disk drives present"),
378 		       sysctl_hw_disknames, 0, NULL, 0,
379 		       CTL_HW, HW_DISKNAMES, CTL_EOL);
380 	sysctl_createv(clog, 0, NULL, NULL,
381 		       CTLFLAG_PERMANENT,
382 		       CTLTYPE_STRING, "iostatnames",
383 		       SYSCTL_DESCR("I/O stats are being collected for these"
384 				    " devices"),
385 		       sysctl_hw_iostatnames, 0, NULL, 0,
386 		       CTL_HW, HW_IOSTATNAMES, CTL_EOL);
387 	sysctl_createv(clog, 0, NULL, NULL,
388 		       CTLFLAG_PERMANENT,
389 		       CTLTYPE_STRUCT, "iostats",
390 		       SYSCTL_DESCR("Statistics on device I/O operations"),
391 		       sysctl_hw_iostats, 0, NULL, 0,
392 		       CTL_HW, HW_IOSTATS, CTL_EOL);
393 }
394