1 /*
2 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved.
3 *
4 * This code is derived from software contributed to The DragonFly Project
5 * by Hiten Pandya <hmp@backplane.com>.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * Useful functions that are used across the source base for
37 * various purpose.
38 */
39
40 #include <sys/param.h>
41 #include <sys/nchstats.h>
42 #include <sys/sysctl.h>
43 #include <strings.h>
44
45 #include "kvm.h"
46
47 /*
48 * Aggregate the per-cpu counters we retrieved via sysctl(2)
49 * to give the total across the CPUs. Use a nasty trick to
50 * aggregate the counters in the structure! YYY
51 */
52 void
kvm_nch_cpuagg(struct nchstats * unagg,struct nchstats * ttl,int cpucnt)53 kvm_nch_cpuagg(struct nchstats *unagg, struct nchstats *ttl, int cpucnt)
54 {
55 int i, off, siz;
56 siz = sizeof(struct nchstats);
57
58 if (!unagg && !ttl)
59 return;
60
61 bzero(ttl, siz);
62
63 /* kick hmp@ for this nasty loop! :-) */
64 for (i = 0; i < cpucnt; ++i) {
65 for (off = 0; off < siz; off += sizeof(u_long)) {
66 *(u_long *)((char *)(*(&ttl)) + off) +=
67 *(u_long *)((char *)&unagg[i] + off);
68 }
69 }
70 }
71