1 /* mallocator - recycle objects to avoid malloc() / free() */
3 /* Copyright (c) 2006-2011. The SimGrid Team.
4 * All rights reserved. */
6 /* This program is free software; you can redistribute it and/or modify it
7 * under the terms of the license (GNU LGPL) which comes with this package. */
9 #include "xbt/mallocator.h"
10 #include "xbt/asserts.h"
11 #include "xbt/sysdep.h"
12 #include "mc/mc.h" /* kill mallocators when model-checking is enabled */
13 #include "mallocator_private.h"
15 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_mallocator, xbt, "Mallocators");
19 * \param size size of the internal stack: number of objects the mallocator
20 * will be able to store
21 * \param new_f function to allocate a new object of your datatype, called
22 * in \a xbt_mallocator_get() when the mallocator is empty
23 * \param free_f function to free an object of your datatype, called
24 * in \a xbt_mallocator_release() when the stack is full, and when
25 * the mallocator is freed.
26 * \param reset_f function to reinitialise an object of your datatype, called
27 * when you extract an object from the mallocator
29 * Create and initialize a new mallocator for a given datatype.
31 * \return pointer to the created mallocator
32 * \see xbt_mallocator_free()
34 xbt_mallocator_t xbt_mallocator_new(int size,
36 void_f_pvoid_t free_f,
37 void_f_pvoid_t reset_f)
43 xbt_assert(size > 0, "size must be positive");
44 xbt_assert(new_f != NULL && free_f != NULL
45 && reset_f != NULL, "invalid parameter");
47 /* Let's force 0 size mallocator! (Dirty hack, blame Martin :) ) */
49 /* mallocators and memory mess introduced by model-checking do not mix well together:
50 * The mallocator will give standard memory when we are using raw memory (so these blocks are killed on restore)
51 * and the contrary (so these blocks will leak accross restores)
56 m = xbt_new0(s_xbt_mallocator_t, 1);
57 XBT_VERB("Create mallocator %p", m);
59 m->objects = xbt_new0(void *, MC_IS_ENABLED ? 1 : size);
70 * \param m the mallocator you want to destroy
72 * Destroy the mallocator and all its data. The function
73 * free_f is called on each object in the mallocator.
75 * \see xbt_mallocator_new()
77 void xbt_mallocator_free(xbt_mallocator_t m)
81 xbt_assert(m != NULL, "Invalid parameter");
83 XBT_VERB("Frees mallocator %p (size:%d/%d)", m, m->current_size,
85 for (i = 0; i < m->current_size; i++) {
86 (*(m->free_f)) (m->objects[i]);
93 * \brief Extract an object from a mallocator
94 * \param m a mallocator
96 * Remove an object from the mallocator and return it.
97 * This function is designed to be used instead of malloc().
98 * If the mallocator is not empty, an object is
99 * extracted from the mallocator and no malloc is done.
101 * If the mallocator is empty, a new object is created,
102 * by calling the function new_f().
104 * In both cases, the function reset_f() is called on the object.
106 * \see xbt_mallocator_release()
108 void *xbt_mallocator_get(xbt_mallocator_t m)
112 if (m->current_size <= 0) {
113 /* No object is ready yet. Create a bunch of them to try to group the mallocs
114 * on the same memory pages (to help the cache lines) */
116 /* XBT_DEBUG("Create a new object for mallocator %p (size:%d/%d)", m,
117 m->current_size, m->max_size); */
119 int amount=MIN( (m->max_size) /2,1000);
120 for (i=0;i<amount;i++)
121 m->objects[i] = (*(m->new_f)) ();
122 m->current_size=amount;
125 /* there is at least an available object, now */
126 /* XBT_DEBUG("Reuse an old object for mallocator %p (size:%d/%d)", m,
127 m->current_size, m->max_size); */
128 if (MC_IS_ENABLED) /* no mallocator with MC */
129 object = (*(m->new_f)) ();
131 object = m->objects[--m->current_size];
133 (*(m->reset_f)) (object);
137 /** \brief Push an object into a mallocator
138 * \param m a mallocator
139 * \param object an object you don't need anymore
141 * Push into the mallocator an object you don't need anymore.
142 * This function is designed to be used instead of free().
143 * If the mallocator is not full, your object if stored into
144 * the mallocator and no free is done.
145 * If the mallocator is full, the object is freed by calling
146 * the function free_f().
148 * \see xbt_mallocator_get()
150 void xbt_mallocator_release(xbt_mallocator_t m, void *object)
152 if (m->current_size < m->max_size) {
153 /* there is enough place to push the object */
155 ("Store deleted object in mallocator %p for further use (size:%d/%d)",
156 m, m->current_size, m->max_size); */
157 m->objects[m->current_size++] = object;
159 /* otherwise we don't have a choice, we must free the object */
160 /* XBT_DEBUG("Free deleted object: mallocator %p is full (size:%d/%d)", m,
161 m->current_size, m->max_size); */
162 (*(m->free_f)) (object);