utcache.c revision 241973 
1/******************************************************************************
2 *
3 * Module Name: utcache - local cache allocation routines
4 *
5 *****************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2012, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions, and the following disclaimer,
16 *    without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 *    substantially similar to the "NO WARRANTY" disclaimer below
19 *    ("Disclaimer") and any redistribution must be conditioned upon
20 *    including a substantially similar Disclaimer requirement for further
21 *    binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 *    of any contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44#define __UTCACHE_C__
45
46#include <contrib/dev/acpica/include/acpi.h>
47#include <contrib/dev/acpica/include/accommon.h>
48
49#define _COMPONENT          ACPI_UTILITIES
50        ACPI_MODULE_NAME    ("utcache")
51
52
53#ifdef ACPI_USE_LOCAL_CACHE
54/*******************************************************************************
55 *
56 * FUNCTION:    AcpiOsCreateCache
57 *
58 * PARAMETERS:  CacheName       - Ascii name for the cache
59 *              ObjectSize      - Size of each cached object
60 *              MaxDepth        - Maximum depth of the cache (in objects)
61 *              ReturnCache     - Where the new cache object is returned
62 *
63 * RETURN:      Status
64 *
65 * DESCRIPTION: Create a cache object
66 *
67 ******************************************************************************/
68
69ACPI_STATUS
70AcpiOsCreateCache (
71    char                    *CacheName,
72    UINT16                  ObjectSize,
73    UINT16                  MaxDepth,
74    ACPI_MEMORY_LIST        **ReturnCache)
75{
76    ACPI_MEMORY_LIST        *Cache;
77
78
79    ACPI_FUNCTION_ENTRY ();
80
81
82    if (!CacheName || !ReturnCache || (ObjectSize < 16))
83    {
84        return (AE_BAD_PARAMETER);
85    }
86
87    /* Create the cache object */
88
89    Cache = AcpiOsAllocate (sizeof (ACPI_MEMORY_LIST));
90    if (!Cache)
91    {
92        return (AE_NO_MEMORY);
93    }
94
95    /* Populate the cache object and return it */
96
97    ACPI_MEMSET (Cache, 0, sizeof (ACPI_MEMORY_LIST));
98    Cache->LinkOffset = 8;
99    Cache->ListName   = CacheName;
100    Cache->ObjectSize = ObjectSize;
101    Cache->MaxDepth   = MaxDepth;
102
103    *ReturnCache = Cache;
104    return (AE_OK);
105}
106
107
108/*******************************************************************************
109 *
110 * FUNCTION:    AcpiOsPurgeCache
111 *
112 * PARAMETERS:  Cache           - Handle to cache object
113 *
114 * RETURN:      Status
115 *
116 * DESCRIPTION: Free all objects within the requested cache.
117 *
118 ******************************************************************************/
119
120ACPI_STATUS
121AcpiOsPurgeCache (
122    ACPI_MEMORY_LIST        *Cache)
123{
124    char                    *Next;
125    ACPI_STATUS             Status;
126
127
128    ACPI_FUNCTION_ENTRY ();
129
130
131    if (!Cache)
132    {
133        return (AE_BAD_PARAMETER);
134    }
135
136    Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
137    if (ACPI_FAILURE (Status))
138    {
139        return (Status);
140    }
141
142    /* Walk the list of objects in this cache */
143
144    while (Cache->ListHead)
145    {
146        /* Delete and unlink one cached state object */
147
148        Next = *(ACPI_CAST_INDIRECT_PTR (char,
149                    &(((char *) Cache->ListHead)[Cache->LinkOffset])));
150        ACPI_FREE (Cache->ListHead);
151
152        Cache->ListHead = Next;
153        Cache->CurrentDepth--;
154    }
155
156    (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
157    return (AE_OK);
158}
159
160
161/*******************************************************************************
162 *
163 * FUNCTION:    AcpiOsDeleteCache
164 *
165 * PARAMETERS:  Cache           - Handle to cache object
166 *
167 * RETURN:      Status
168 *
169 * DESCRIPTION: Free all objects within the requested cache and delete the
170 *              cache object.
171 *
172 ******************************************************************************/
173
174ACPI_STATUS
175AcpiOsDeleteCache (
176    ACPI_MEMORY_LIST        *Cache)
177{
178    ACPI_STATUS             Status;
179
180
181    ACPI_FUNCTION_ENTRY ();
182
183
184   /* Purge all objects in the cache */
185
186    Status = AcpiOsPurgeCache (Cache);
187    if (ACPI_FAILURE (Status))
188    {
189        return (Status);
190    }
191
192    /* Now we can delete the cache object */
193
194    AcpiOsFree (Cache);
195    return (AE_OK);
196}
197
198
199/*******************************************************************************
200 *
201 * FUNCTION:    AcpiOsReleaseObject
202 *
203 * PARAMETERS:  Cache       - Handle to cache object
204 *              Object      - The object to be released
205 *
206 * RETURN:      None
207 *
208 * DESCRIPTION: Release an object to the specified cache. If cache is full,
209 *              the object is deleted.
210 *
211 ******************************************************************************/
212
213ACPI_STATUS
214AcpiOsReleaseObject (
215    ACPI_MEMORY_LIST        *Cache,
216    void                    *Object)
217{
218    ACPI_STATUS             Status;
219
220
221    ACPI_FUNCTION_ENTRY ();
222
223
224    if (!Cache || !Object)
225    {
226        return (AE_BAD_PARAMETER);
227    }
228
229    /* If cache is full, just free this object */
230
231    if (Cache->CurrentDepth >= Cache->MaxDepth)
232    {
233        ACPI_FREE (Object);
234        ACPI_MEM_TRACKING (Cache->TotalFreed++);
235    }
236
237    /* Otherwise put this object back into the cache */
238
239    else
240    {
241        Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
242        if (ACPI_FAILURE (Status))
243        {
244            return (Status);
245        }
246
247        /* Mark the object as cached */
248
249        ACPI_MEMSET (Object, 0xCA, Cache->ObjectSize);
250        ACPI_SET_DESCRIPTOR_TYPE (Object, ACPI_DESC_TYPE_CACHED);
251
252        /* Put the object at the head of the cache list */
253
254        * (ACPI_CAST_INDIRECT_PTR (char,
255            &(((char *) Object)[Cache->LinkOffset]))) = Cache->ListHead;
256        Cache->ListHead = Object;
257        Cache->CurrentDepth++;
258
259        (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
260    }
261
262    return (AE_OK);
263}
264
265
266/*******************************************************************************
267 *
268 * FUNCTION:    AcpiOsAcquireObject
269 *
270 * PARAMETERS:  Cache           - Handle to cache object
271 *
272 * RETURN:      the acquired object. NULL on error
273 *
274 * DESCRIPTION: Get an object from the specified cache. If cache is empty,
275 *              the object is allocated.
276 *
277 ******************************************************************************/
278
279void *
280AcpiOsAcquireObject (
281    ACPI_MEMORY_LIST        *Cache)
282{
283    ACPI_STATUS             Status;
284    void                    *Object;
285
286
287    ACPI_FUNCTION_NAME (OsAcquireObject);
288
289
290    if (!Cache)
291    {
292        return (NULL);
293    }
294
295    Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
296    if (ACPI_FAILURE (Status))
297    {
298        return (NULL);
299    }
300
301    ACPI_MEM_TRACKING (Cache->Requests++);
302
303    /* Check the cache first */
304
305    if (Cache->ListHead)
306    {
307        /* There is an object available, use it */
308
309        Object = Cache->ListHead;
310        Cache->ListHead = *(ACPI_CAST_INDIRECT_PTR (char,
311                                &(((char *) Object)[Cache->LinkOffset])));
312
313        Cache->CurrentDepth--;
314
315        ACPI_MEM_TRACKING (Cache->Hits++);
316        ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
317            "Object %p from %s cache\n", Object, Cache->ListName));
318
319        Status = AcpiUtReleaseMutex (ACPI_MTX_CACHES);
320        if (ACPI_FAILURE (Status))
321        {
322            return (NULL);
323        }
324
325        /* Clear (zero) the previously used Object */
326
327        ACPI_MEMSET (Object, 0, Cache->ObjectSize);
328    }
329    else
330    {
331        /* The cache is empty, create a new object */
332
333        ACPI_MEM_TRACKING (Cache->TotalAllocated++);
334
335#ifdef ACPI_DBG_TRACK_ALLOCATIONS
336        if ((Cache->TotalAllocated - Cache->TotalFreed) > Cache->MaxOccupied)
337        {
338            Cache->MaxOccupied = Cache->TotalAllocated - Cache->TotalFreed;
339        }
340#endif
341
342        /* Avoid deadlock with ACPI_ALLOCATE_ZEROED */
343
344        Status = AcpiUtReleaseMutex (ACPI_MTX_CACHES);
345        if (ACPI_FAILURE (Status))
346        {
347            return (NULL);
348        }
349
350        Object = ACPI_ALLOCATE_ZEROED (Cache->ObjectSize);
351        if (!Object)
352        {
353            return (NULL);
354        }
355    }
356
357    return (Object);
358}
359#endif /* ACPI_USE_LOCAL_CACHE */
360