xref: /netbsd-src/sys/dev/raidframe/rf_alloclist.c (revision 08c81a9c2dc8c7300e893321eb65c0925d60871c)
1 /*	$NetBSD: rf_alloclist.c,v 1.10 2002/09/14 17:53:57 oster Exp $	*/
2 /*
3  * Copyright (c) 1995 Carnegie-Mellon University.
4  * All rights reserved.
5  *
6  * Author: Mark Holland
7  *
8  * Permission to use, copy, modify and distribute this software and
9  * its documentation is hereby granted, provided that both the copyright
10  * notice and this permission notice appear in all copies of the
11  * software, derivative works or modified versions, and any portions
12  * thereof, and that both notices appear in supporting documentation.
13  *
14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
16  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17  *
18  * Carnegie Mellon requests users of this software to return to
19  *
20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21  *  School of Computer Science
22  *  Carnegie Mellon University
23  *  Pittsburgh PA 15213-3890
24  *
25  * any improvements or extensions that they make and grant Carnegie the
26  * rights to redistribute these changes.
27  */
28 
29 /****************************************************************************
30  *
31  * Alloclist.c -- code to manipulate allocation lists
32  *
33  * an allocation list is just a list of AllocListElem structures.  Each
34  * such structure contains a fixed-size array of pointers.  Calling
35  * FreeAList() causes each pointer to be freed.
36  *
37  ***************************************************************************/
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: rf_alloclist.c,v 1.10 2002/09/14 17:53:57 oster Exp $");
41 
42 #include <dev/raidframe/raidframevar.h>
43 
44 #include "rf_options.h"
45 #include "rf_threadstuff.h"
46 #include "rf_alloclist.h"
47 #include "rf_debugMem.h"
48 #include "rf_etimer.h"
49 #include "rf_general.h"
50 #include "rf_shutdown.h"
51 
52 RF_DECLARE_STATIC_MUTEX(alist_mutex)
53 static unsigned int fl_hit_count, fl_miss_count;
54 
55 static RF_AllocListElem_t *al_free_list = NULL;
56 static int al_free_list_count;
57 
58 #define RF_AL_FREELIST_MAX 256
59 
60 #define DO_FREE(_p,_sz) RF_Free((_p),(_sz))
61 
62 static void rf_ShutdownAllocList(void *);
63 
64 static void rf_ShutdownAllocList(ignored)
65 	void   *ignored;
66 {
67 	RF_AllocListElem_t *p, *pt;
68 
69 	for (p = al_free_list; p;) {
70 		pt = p;
71 		p = p->next;
72 		DO_FREE(pt, sizeof(*pt));
73 	}
74 	rf_mutex_destroy(&alist_mutex);
75 	/*
76         printf("Alloclist: Free list hit count %lu (%lu %%) miss count %lu (%lu %%)\n",
77 	       fl_hit_count, (100*fl_hit_count)/(fl_hit_count+fl_miss_count),
78 	       fl_miss_count, (100*fl_miss_count)/(fl_hit_count+fl_miss_count));
79         */
80 }
81 
82 int
83 rf_ConfigureAllocList(listp)
84 	RF_ShutdownList_t **listp;
85 {
86 	int     rc;
87 
88 	rc = rf_mutex_init(&alist_mutex);
89 	if (rc) {
90 		rf_print_unable_to_init_mutex( __FILE__, __LINE__, rc);
91 		return (rc);
92 	}
93 	al_free_list = NULL;
94 	fl_hit_count = fl_miss_count = al_free_list_count = 0;
95 	rc = rf_ShutdownCreate(listp, rf_ShutdownAllocList, NULL);
96 	if (rc) {
97 		rf_print_unable_to_add_shutdown( __FILE__, __LINE__, rc);
98 		rf_mutex_destroy(&alist_mutex);
99 		return (rc);
100 	}
101 	return (0);
102 }
103 
104 
105 /* we expect the lists to have at most one or two elements, so we're willing
106  * to search for the end.  If you ever observe the lists growing longer,
107  * increase POINTERS_PER_ALLOC_LIST_ELEMENT.
108  */
109 void
110 rf_real_AddToAllocList(l, p, size, lockflag)
111 	RF_AllocListElem_t *l;
112 	void   *p;
113 	int     size;
114 	int     lockflag;
115 {
116 	RF_AllocListElem_t *newelem;
117 
118 	for (; l->next; l = l->next)
119 		RF_ASSERT(l->numPointers == RF_POINTERS_PER_ALLOC_LIST_ELEMENT);	/* find end of list */
120 
121 	RF_ASSERT(l->numPointers >= 0 && l->numPointers <= RF_POINTERS_PER_ALLOC_LIST_ELEMENT);
122 	if (l->numPointers == RF_POINTERS_PER_ALLOC_LIST_ELEMENT) {
123 		newelem = rf_real_MakeAllocList(lockflag);
124 		l->next = newelem;
125 		l = newelem;
126 	}
127 	l->pointers[l->numPointers] = p;
128 	l->sizes[l->numPointers] = size;
129 	l->numPointers++;
130 
131 }
132 
133 
134 /* we use the debug_mem_mutex here because we need to lock it anyway to call free.
135  * this is probably a bug somewhere else in the code, but when I call malloc/free
136  * outside of any lock I have endless trouble with malloc appearing to return the
137  * same pointer twice.  Since we have to lock it anyway, we might as well use it
138  * as the lock around the al_free_list.  Note that we can't call Free with the
139  * debug_mem_mutex locked.
140  */
141 void
142 rf_FreeAllocList(l)
143 	RF_AllocListElem_t *l;
144 {
145 	int     i;
146 	RF_AllocListElem_t *temp, *p;
147 
148 	for (p = l; p; p = p->next) {
149 		RF_ASSERT(p->numPointers >= 0 && p->numPointers <= RF_POINTERS_PER_ALLOC_LIST_ELEMENT);
150 		for (i = 0; i < p->numPointers; i++) {
151 			RF_ASSERT(p->pointers[i]);
152 			RF_Free(p->pointers[i], p->sizes[i]);
153 		}
154 	}
155 	while (l) {
156 		temp = l;
157 		l = l->next;
158 		if (al_free_list_count > RF_AL_FREELIST_MAX) {
159 			DO_FREE(temp, sizeof(*temp));
160 		} else {
161 			temp->next = al_free_list;
162 			al_free_list = temp;
163 			al_free_list_count++;
164 		}
165 	}
166 }
167 
168 RF_AllocListElem_t *
169 rf_real_MakeAllocList(lockflag)
170 	int     lockflag;
171 {
172 	RF_AllocListElem_t *p;
173 
174 	if (al_free_list) {
175 		fl_hit_count++;
176 		p = al_free_list;
177 		al_free_list = p->next;
178 		al_free_list_count--;
179 	} else {
180 		fl_miss_count++;
181 		RF_Malloc(p, sizeof(RF_AllocListElem_t), (RF_AllocListElem_t *));	/* no allocation locking
182 											 * in kernel, so this is
183 											 * fine */
184 	}
185 	if (p == NULL) {
186 		return (NULL);
187 	}
188 	memset((char *) p, 0, sizeof(RF_AllocListElem_t));
189 	return (p);
190 }
191