xref: /netbsd-src/sys/kern/subr_iostat.c (revision b7ae68fde0d8ef1c03714e8bbb1ee7c6118ea93b)
1 /*	$NetBSD: subr_iostat.c,v 1.11 2006/08/23 17:19:32 christos 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 1.11 2006/08/23 17:19:32 christos 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, void *parent, const char *name)
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 	stats->io_parent = parent;
143 	(void)strlcpy(stats->io_name, name, sizeof(stats->io_name));
144 
145 	/*
146 	 * Set the attached timestamp.
147 	 */
148 	getmicrouptime(&stats->io_attachtime);
149 
150 	/*
151 	 * Link into the drivelist.
152 	 */
153 	simple_lock(&iostatlist_slock);
154 	TAILQ_INSERT_TAIL(&iostatlist, stats, io_link);
155 	iostat_count++;
156 	simple_unlock(&iostatlist_slock);
157 
158 	return stats;
159 }
160 
161 /*
162  * Remove i/o from stats collection.
163  */
164 void
165 iostat_free(struct io_stats *stats)
166 {
167 
168 	/*
169 	 * Remove from the iostat list.
170 	 */
171 	if (iostat_count == 0)
172 		panic("iostat_free: iostat_count == 0");
173 	simple_lock(&iostatlist_slock);
174 	TAILQ_REMOVE(&iostatlist, stats, io_link);
175 	iostat_count--;
176 	simple_unlock(&iostatlist_slock);
177 	free(stats, M_DEVBUF);
178 }
179 
180 /*
181  * Increment a iostat busy counter.  If the counter is going from
182  * 0 to 1, set the timestamp.
183  */
184 void
185 iostat_busy(struct io_stats *stats)
186 {
187 
188 	if (stats->io_busy++ == 0)
189 		getmicrouptime(&stats->io_timestamp);
190 }
191 
192 /*
193  * Decrement a iostat busy counter, increment the byte count, total busy
194  * time, and reset the timestamp.
195  */
196 void
197 iostat_unbusy(struct io_stats *stats, long bcount, int read)
198 {
199 	struct timeval dv_time, diff_time;
200 
201 	if (stats->io_busy-- == 0) {
202 		printf("%s: busy < 0\n", stats->io_name);
203 		panic("iostat_unbusy");
204 	}
205 
206 	getmicrouptime(&dv_time);
207 
208 	timersub(&dv_time, &stats->io_timestamp, &diff_time);
209 	timeradd(&stats->io_time, &diff_time, &stats->io_time);
210 
211 	stats->io_timestamp = dv_time;
212 	if (bcount > 0) {
213 		if (read) {
214 			stats->io_rbytes += bcount;
215 			stats->io_rxfer++;
216 		} else {
217 			stats->io_wbytes += bcount;
218 			stats->io_wxfer++;
219 		}
220 	}
221 }
222 
223 /*
224  * Increment the seek counter.  This does look almost redundant but it
225  * abstracts the stats gathering.
226  */
227 void
228 iostat_seek(struct io_stats *stats)
229 {
230 
231 	stats->io_seek++;
232 }
233 
234 static int
235 sysctl_hw_disknames(SYSCTLFN_ARGS)
236 {
237 
238 	return iostati_getnames(1, oldp, oldlenp, newp, namelen);
239 }
240 
241 static int
242 sysctl_hw_iostatnames(SYSCTLFN_ARGS)
243 {
244 
245 	return iostati_getnames(0, oldp, oldlenp, newp, namelen);
246 }
247 
248 static int
249 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp,
250 		 u_int namelen)
251 {
252 	char bf[IOSTATNAMELEN + 1];
253 	char *where = oldp;
254 	struct io_stats *stats;
255 	size_t needed, left, slen;
256 	int error, first;
257 
258 	if (newp != NULL)
259 		return (EPERM);
260 	if (namelen != 0)
261 		return (EINVAL);
262 
263 	first = 1;
264 	error = 0;
265 	needed = 0;
266 	left = *oldlenp;
267 
268 	simple_lock(&iostatlist_slock);
269 	for (stats = TAILQ_FIRST(&iostatlist); stats != NULL;
270 	    stats = TAILQ_NEXT(stats, io_link)) {
271 		if ((disk_only == 1) && (stats->io_type != IOSTAT_DISK))
272 			continue;
273 
274 		if (where == NULL)
275 			needed += strlen(stats->io_name) + 1;
276 		else {
277 			memset(bf, 0, sizeof(bf));
278 			if (first) {
279 				strncpy(bf, stats->io_name, sizeof(bf));
280 				first = 0;
281 			} else {
282 				bf[0] = ' ';
283 				strncpy(bf + 1, stats->io_name,
284 				    sizeof(bf) - 1);
285 			}
286 			bf[IOSTATNAMELEN] = '\0';
287 			slen = strlen(bf);
288 			if (left < slen + 1)
289 				break;
290 			/* +1 to copy out the trailing NUL byte */
291 			error = copyout(bf, where, slen + 1);
292 			if (error)
293 				break;
294 			where += slen;
295 			needed += slen;
296 			left -= slen;
297 		}
298 	}
299 	simple_unlock(&iostatlist_slock);
300 	*oldlenp = needed;
301 	return (error);
302 }
303 
304 static int
305 sysctl_hw_iostats(SYSCTLFN_ARGS)
306 {
307 	struct io_sysctl sdrive;
308 	struct io_stats *stats;
309 	char *where = oldp;
310 	size_t tocopy, left;
311 	int error;
312 
313 	if (newp != NULL)
314 		return (EPERM);
315 
316 	/*
317 	 * The original hw.diskstats call was broken and did not require
318 	 * the userland to pass in it's size of struct disk_sysctl.  This
319 	 * was fixed after NetBSD 1.6 was released, and any applications
320 	 * that do not pass in the size are given an error only, unless
321 	 * we care about 1.6 compatibility.
322 	 */
323 	if (namelen == 0)
324 #ifdef COMPAT_16
325 		tocopy = offsetof(struct io_sysctl, busy);
326 #else
327 		return (EINVAL);
328 #endif
329 	else
330 		tocopy = name[0];
331 
332 	if (where == NULL) {
333 		*oldlenp = iostat_count * tocopy;
334 		return (0);
335 	}
336 
337 	error = 0;
338 	left = *oldlenp;
339 	memset(&sdrive, 0, sizeof(sdrive));
340 	*oldlenp = 0;
341 
342 	simple_lock(&iostatlist_slock);
343 	TAILQ_FOREACH(stats, &iostatlist, io_link) {
344 		if (left < tocopy)
345 			break;
346 		strncpy(sdrive.name, stats->io_name, sizeof(sdrive.name));
347 		sdrive.xfer = stats->io_rxfer + stats->io_wxfer;
348 		sdrive.rxfer = stats->io_rxfer;
349 		sdrive.wxfer = stats->io_wxfer;
350 		sdrive.seek = stats->io_seek;
351 		sdrive.bytes = stats->io_rbytes + stats->io_wbytes;
352 		sdrive.rbytes = stats->io_rbytes;
353 		sdrive.wbytes = stats->io_wbytes;
354 		sdrive.attachtime_sec = stats->io_attachtime.tv_sec;
355 		sdrive.attachtime_usec = stats->io_attachtime.tv_usec;
356 		sdrive.timestamp_sec = stats->io_timestamp.tv_sec;
357 		sdrive.timestamp_usec = stats->io_timestamp.tv_usec;
358 		sdrive.time_sec = stats->io_time.tv_sec;
359 		sdrive.time_usec = stats->io_time.tv_usec;
360 		sdrive.busy = stats->io_busy;
361 
362 		error = copyout(&sdrive, where, min(tocopy, sizeof(sdrive)));
363 		if (error)
364 			break;
365 		where += tocopy;
366 		*oldlenp += tocopy;
367 		left -= tocopy;
368 	}
369 	simple_unlock(&iostatlist_slock);
370 	return (error);
371 }
372 
373 SYSCTL_SETUP(sysctl_io_stats_setup, "sysctl i/o stats setup")
374 {
375 
376 	sysctl_createv(clog, 0, NULL, NULL,
377 		       CTLFLAG_PERMANENT,
378 		       CTLTYPE_STRING, "disknames",
379 		       SYSCTL_DESCR("List of disk drives present"),
380 		       sysctl_hw_disknames, 0, NULL, 0,
381 		       CTL_HW, HW_DISKNAMES, CTL_EOL);
382 	sysctl_createv(clog, 0, NULL, NULL,
383 		       CTLFLAG_PERMANENT,
384 		       CTLTYPE_STRING, "iostatnames",
385 		       SYSCTL_DESCR("I/O stats are being collected for these"
386 				    " devices"),
387 		       sysctl_hw_iostatnames, 0, NULL, 0,
388 		       CTL_HW, HW_IOSTATNAMES, CTL_EOL);
389 	sysctl_createv(clog, 0, NULL, NULL,
390 		       CTLFLAG_PERMANENT,
391 		       CTLTYPE_STRUCT, "iostats",
392 		       SYSCTL_DESCR("Statistics on device I/O operations"),
393 		       sysctl_hw_iostats, 0, NULL, 0,
394 		       CTL_HW, HW_IOSTATS, CTL_EOL);
395 }
396