xref: /netbsd-src/sys/kern/kern_history.c (revision a536ee5124e62c9a0051a252f7833dc8f50f44c9)
1 /*	$NetBSD: kern_history.c,v 1.1 2011/05/17 04:18:06 mrg Exp $	 */
2 
3 /*
4  * Copyright (c) 1997 Charles D. Cranor and Washington University.
5  * All rights reserved.
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  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  * from: NetBSD: uvm_stat.c,v 1.36 2011/02/02 15:13:34 chuck Exp
28  * from: Id: uvm_stat.c,v 1.1.2.3 1997/12/19 15:01:00 mrg Exp
29  */
30 
31 /*
32  * subr_kernhist.c
33  */
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: kern_history.c,v 1.1 2011/05/17 04:18:06 mrg Exp $");
37 
38 #include "opt_kernhist.h"
39 #include "opt_uvmhist.h"
40 #include "opt_ddb.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/cpu.h>
45 #include <sys/kernhist.h>
46 
47 #include <uvm/uvm.h>
48 
49 /*
50  * globals
51  */
52 
53 struct kern_history_head kern_histories;
54 
55 int kernhist_print_enabled = 1;
56 
57 #ifdef DDB
58 
59 /*
60  * prototypes
61  */
62 
63 void kernhist_dump(struct kern_history *);
64 void kernhist_dumpmask(u_int32_t);
65 static void kernhist_dump_histories(struct kern_history *[]);
66 
67 
68 /*
69  * call this from ddb
70  *
71  * expects the system to be quiesced, no locking
72  */
73 void
74 kernhist_dump(struct kern_history *l)
75 {
76 	int lcv;
77 
78 	lcv = l->f;
79 	do {
80 		if (l->e[lcv].fmt)
81 			kernhist_entry_print(&l->e[lcv]);
82 		lcv = (lcv + 1) % l->n;
83 	} while (lcv != l->f);
84 }
85 
86 /*
87  * print a merged list of kern_history structures
88  */
89 static void
90 kernhist_dump_histories(struct kern_history *hists[])
91 {
92 	struct timeval  tv;
93 	int	cur[MAXHISTS];
94 	int	lcv, hi;
95 
96 	/* find the first of each list */
97 	for (lcv = 0; hists[lcv]; lcv++)
98 		 cur[lcv] = hists[lcv]->f;
99 
100 	/*
101 	 * here we loop "forever", finding the next earliest
102 	 * history entry and printing it.  cur[X] is the current
103 	 * entry to test for the history in hists[X].  if it is
104 	 * -1, then this history is finished.
105 	 */
106 	for (;;) {
107 		hi = -1;
108 		tv.tv_sec = tv.tv_usec = 0;
109 
110 		/* loop over each history */
111 		for (lcv = 0; hists[lcv]; lcv++) {
112 restart:
113 			if (cur[lcv] == -1)
114 				continue;
115 
116 			/*
117 			 * if the format is empty, go to the next entry
118 			 * and retry.
119 			 */
120 			if (hists[lcv]->e[cur[lcv]].fmt == NULL) {
121 				cur[lcv] = (cur[lcv] + 1) % (hists[lcv]->n);
122 				if (cur[lcv] == hists[lcv]->f)
123 					cur[lcv] = -1;
124 				goto restart;
125 			}
126 
127 			/*
128 			 * if the time hasn't been set yet, or this entry is
129 			 * earlier than the current tv, set the time and history
130 			 * index.
131 			 */
132 			if (tv.tv_sec == 0 ||
133 			    timercmp(&hists[lcv]->e[cur[lcv]].tv, &tv, <)) {
134 				tv = hists[lcv]->e[cur[lcv]].tv;
135 				hi = lcv;
136 			}
137 		}
138 
139 		/* if we didn't find any entries, we must be done */
140 		if (hi == -1)
141 			break;
142 
143 		/* print and move to the next entry */
144 		kernhist_entry_print(&hists[hi]->e[cur[hi]]);
145 		cur[hi] = (cur[hi] + 1) % (hists[hi]->n);
146 		if (cur[hi] == hists[hi]->f)
147 			cur[hi] = -1;
148 	}
149 }
150 
151 /*
152  * call this from ddb.  `bitmask' is from <sys/kernhist.h>.  it
153  * merges the named histories.
154  *
155  * expects the system to be quiesced, no locking
156  */
157 void
158 kernhist_dumpmask(u_int32_t bitmask)	/* XXX only support 32 hists */
159 {
160 	struct kern_history *hists[MAXHISTS + 1];
161 	int i = 0;
162 
163 #ifdef UVMHIST
164 	if ((bitmask & KERNHIST_UVMMAPHIST) || bitmask == 0)
165 		hists[i++] = &maphist;
166 
167 	if ((bitmask & KERNHIST_UVMPDHIST) || bitmask == 0)
168 		hists[i++] = &pdhist;
169 
170 	if ((bitmask & KERNHIST_UVMUBCHIST) || bitmask == 0)
171 		hists[i++] = &ubchist;
172 
173 	if ((bitmask & KERNHIST_UVMLOANHIST) || bitmask == 0)
174 		hists[i++] = &loanhist;
175 #endif
176 
177 	hists[i] = NULL;
178 
179 	kernhist_dump_histories(hists);
180 }
181 
182 /*
183  * kernhist_print: ddb hook to print kern history
184  */
185 void
186 kernhist_print(void (*pr)(const char *, ...))
187 {
188 	kernhist_dump(LIST_FIRST(&kern_histories));
189 }
190 
191 #endif
192