1 /*	$OpenBSD: rf_alloclist.c,v 1.4 2002/12/16 07:01:03 tdeval Exp $	*/
2 /*	$NetBSD: rf_alloclist.c,v 1.4 1999/08/13 03:41:53 oster Exp $	*/
3 
4 /*
5  * Copyright (c) 1995 Carnegie-Mellon University.
6  * All rights reserved.
7  *
8  * Author: Mark Holland
9  *
10  * Permission to use, copy, modify and distribute this software and
11  * its documentation is hereby granted, provided that both the copyright
12  * notice and this permission notice appear in all copies of the
13  * software, derivative works or modified versions, and any portions
14  * thereof, and that both notices appear in supporting documentation.
15  *
16  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19  *
20  * Carnegie Mellon requests users of this software to return to
21  *
22  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23  *  School of Computer Science
24  *  Carnegie Mellon University
25  *  Pittsburgh PA 15213-3890
26  *
27  * any improvements or extensions that they make and grant Carnegie the
28  * rights to redistribute these changes.
29  */
30 
31 /****************************************************************************
32  *
33  * Alloclist.c -- Code to manipulate allocation lists.
34  *
35  * An allocation list is just a list of AllocListElem structures. Each
36  * such structure contains a fixed-size array of pointers. Calling
37  * FreeAList() causes each pointer to be freed.
38  *
39  ***************************************************************************/
40 
41 #include "rf_types.h"
42 #include "rf_threadstuff.h"
43 #include "rf_alloclist.h"
44 #include "rf_debugMem.h"
45 #include "rf_etimer.h"
46 #include "rf_general.h"
47 #include "rf_shutdown.h"
48 
49 RF_DECLARE_STATIC_MUTEX(alist_mutex);
50 static unsigned int fl_hit_count, fl_miss_count;
51 
52 static RF_AllocListElem_t *al_free_list = NULL;
53 static int al_free_list_count;
54 
55 #define	RF_AL_FREELIST_MAX	256
56 
57 #define	DO_FREE(_p,_sz)		RF_Free((_p), (_sz))
58 
59 void rf_ShutdownAllocList(void *);
60 
61 void
rf_ShutdownAllocList(void * ignored)62 rf_ShutdownAllocList(void *ignored)
63 {
64 	RF_AllocListElem_t *p, *pt;
65 
66 	for (p = al_free_list; p;) {
67 		pt = p;
68 		p = p->next;
69 		DO_FREE(pt, sizeof(*pt));
70 	}
71 	rf_mutex_destroy(&alist_mutex);
72 	/*
73 	 * printf("Alloclist: Free list hit count %lu (%lu %%) miss count %lu"
74 	 *     " (%lu %%).\n", fl_hit_count,
75 	 *     (100*fl_hit_count)/(fl_hit_count+fl_miss_count),
76 	 *     fl_miss_count, (100*fl_miss_count)/(fl_hit_count+fl_miss_count));
77 	 */
78 }
79 
80 int
rf_ConfigureAllocList(RF_ShutdownList_t ** listp)81 rf_ConfigureAllocList(RF_ShutdownList_t **listp)
82 {
83 	int rc;
84 
85 	rc = rf_mutex_init(&alist_mutex);
86 	if (rc) {
87 		RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d.\n",
88 		    __FILE__, __LINE__, rc);
89 		return (rc);
90 	}
91 	al_free_list = NULL;
92 	fl_hit_count = fl_miss_count = al_free_list_count = 0;
93 	rc = rf_ShutdownCreate(listp, rf_ShutdownAllocList, NULL);
94 	if (rc) {
95 		RF_ERRORMSG3("Unable to add to shutdown list file %s line %d"
96 		    " rc=%d.\n", __FILE__, __LINE__, rc);
97 		rf_mutex_destroy(&alist_mutex);
98 		return (rc);
99 	}
100 	return (0);
101 }
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
rf_real_AddToAllocList(RF_AllocListElem_t * l,void * p,int size,int lockflag)110 rf_real_AddToAllocList(RF_AllocListElem_t *l, void *p, int size, int lockflag)
111 {
112 	RF_AllocListElem_t *newelem;
113 
114 	for (; l->next; l = l->next)
115 		RF_ASSERT(l->numPointers == RF_POINTERS_PER_ALLOC_LIST_ELEMENT);	/* Find end of list. */
116 
117 	RF_ASSERT(l->numPointers >= 0 &&
118 	    l->numPointers <= RF_POINTERS_PER_ALLOC_LIST_ELEMENT);
119 	if (l->numPointers == RF_POINTERS_PER_ALLOC_LIST_ELEMENT) {
120 		newelem = rf_real_MakeAllocList(lockflag);
121 		l->next = newelem;
122 		l = newelem;
123 	}
124 	l->pointers[l->numPointers] = p;
125 	l->sizes[l->numPointers] = size;
126 	l->numPointers++;
127 
128 }
129 
130 
131 /*
132  * We use the debug_mem_mutex here because we need to lock it anyway to call
133  * free. This is probably a bug somewhere else in the code, but when I call
134  * malloc/free outside of any lock, I have endless trouble with malloc
135  * appearing to return the same pointer twice. Since we have to lock it
136  * anyway, we might as well use it as the lock around the al_free_list.
137  * Note that we can't call Free with the debug_mem_mutex locked.
138  */
139 void
rf_FreeAllocList(RF_AllocListElem_t * l)140 rf_FreeAllocList(RF_AllocListElem_t *l)
141 {
142 	int i;
143 	RF_AllocListElem_t *temp, *p;
144 
145 	for (p = l; p; p = p->next) {
146 		RF_ASSERT(p->numPointers >= 0 &&
147 		    p->numPointers <= RF_POINTERS_PER_ALLOC_LIST_ELEMENT);
148 		for (i = 0; i < p->numPointers; i++) {
149 			RF_ASSERT(p->pointers[i]);
150 			RF_Free(p->pointers[i], p->sizes[i]);
151 		}
152 	}
153 	while (l) {
154 		temp = l;
155 		l = l->next;
156 		if (al_free_list_count > RF_AL_FREELIST_MAX) {
157 			DO_FREE(temp, sizeof(*temp));
158 		} else {
159 			temp->next = al_free_list;
160 			al_free_list = temp;
161 			al_free_list_count++;
162 		}
163 	}
164 }
165 
166 RF_AllocListElem_t *
rf_real_MakeAllocList(int lockflag)167 rf_real_MakeAllocList(int lockflag)
168 {
169 	RF_AllocListElem_t *p;
170 
171 	if (al_free_list) {
172 		fl_hit_count++;
173 		p = al_free_list;
174 		al_free_list = p->next;
175 		al_free_list_count--;
176 	} else {
177 		fl_miss_count++;
178 		RF_Malloc(p, sizeof(RF_AllocListElem_t),
179 		    (RF_AllocListElem_t *));	/*
180 						 * No allocation locking
181 						 * in kernel, so this is
182 						 * fine.
183 						 */
184 	}
185 	if (p == NULL) {
186 		return (NULL);
187 	}
188 	bzero((char *) p, sizeof(RF_AllocListElem_t));
189 	return (p);
190 }
191