drivers/bus/acpi/acpica/utilities/utcache.c

   1 /******************************************************************************
   2  *
   3  * Module Name: utcache - local cache allocation routines
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2019, 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 #include "acpi.h"
  45 #include "accommon.h"
  46
  47 #define _COMPONENT          ACPI_UTILITIES
  48         ACPI_MODULE_NAME    ("utcache")
  49
  50
  51 #ifdef ACPI_USE_LOCAL_CACHE
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    AcpiOsCreateCache
  55  *
  56  * PARAMETERS:  CacheName       - Ascii name for the cache
  57  *              ObjectSize      - Size of each cached object
  58  *              MaxDepth        - Maximum depth of the cache (in objects)
  59  *              ReturnCache     - Where the new cache object is returned
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Create a cache object
  64  *
  65  ******************************************************************************/
  66
  67 ACPI_STATUS
  68 AcpiOsCreateCache (
  69     char                    *CacheName,
  70     UINT16                  ObjectSize,
  71     UINT16                  MaxDepth,
  72     ACPI_MEMORY_LIST        **ReturnCache)
  73 {
  74     ACPI_MEMORY_LIST        *Cache;
  75
  76
  77     ACPI_FUNCTION_ENTRY ();
  78
  79
  80     if (!CacheName || !ReturnCache || !ObjectSize)
  81     {
  82         return (AE_BAD_PARAMETER);
  83     }
  84
  85     /* Create the cache object */
  86
  87     Cache = AcpiOsAllocate (sizeof (ACPI_MEMORY_LIST));
  88     if (!Cache)
  89     {
  90         return (AE_NO_MEMORY);
  91     }
  92
  93     /* Populate the cache object and return it */
  94
  95     memset (Cache, 0, sizeof (ACPI_MEMORY_LIST));
  96     Cache->ListName = CacheName;
  97     Cache->ObjectSize = ObjectSize;
  98     Cache->MaxDepth = MaxDepth;
  99
 100     *ReturnCache = Cache;
 101     return (AE_OK);
 102 }
 103
 104
 105 /*******************************************************************************
 106  *
 107  * FUNCTION:    AcpiOsPurgeCache
 108  *
 109  * PARAMETERS:  Cache           - Handle to cache object
 110  *
 111  * RETURN:      Status
 112  *
 113  * DESCRIPTION: Free all objects within the requested cache.
 114  *
 115  ******************************************************************************/
 116
 117 ACPI_STATUS
 118 AcpiOsPurgeCache (
 119     ACPI_MEMORY_LIST        *Cache)
 120 {
 121     void                    *Next;
 122     ACPI_STATUS             Status;
 123
 124
 125     ACPI_FUNCTION_ENTRY ();
 126
 127
 128     if (!Cache)
 129     {
 130         return (AE_BAD_PARAMETER);
 131     }
 132
 133     Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
 134     if (ACPI_FAILURE (Status))
 135     {
 136         return (Status);
 137     }
 138
 139     /* Walk the list of objects in this cache */
 140
 141     while (Cache->ListHead)
 142     {
 143         /* Delete and unlink one cached state object */
 144
 145         Next = ACPI_GET_DESCRIPTOR_PTR (Cache->ListHead);
 146         ACPI_FREE (Cache->ListHead);
 147
 148         Cache->ListHead = Next;
 149         Cache->CurrentDepth--;
 150     }
 151
 152     (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 153     return (AE_OK);
 154 }
 155
 156
 157 /*******************************************************************************
 158  *
 159  * FUNCTION:    AcpiOsDeleteCache
 160  *
 161  * PARAMETERS:  Cache           - Handle to cache object
 162  *
 163  * RETURN:      Status
 164  *
 165  * DESCRIPTION: Free all objects within the requested cache and delete the
 166  *              cache object.
 167  *
 168  ******************************************************************************/
 169
 170 ACPI_STATUS
 171 AcpiOsDeleteCache (
 172     ACPI_MEMORY_LIST        *Cache)
 173 {
 174     ACPI_STATUS             Status;
 175
 176
 177     ACPI_FUNCTION_ENTRY ();
 178
 179
 180    /* Purge all objects in the cache */
 181
 182     Status = AcpiOsPurgeCache (Cache);
 183     if (ACPI_FAILURE (Status))
 184     {
 185         return (Status);
 186     }
 187
 188     /* Now we can delete the cache object */
 189
 190     AcpiOsFree (Cache);
 191     return (AE_OK);
 192 }
 193
 194
 195 /*******************************************************************************
 196  *
 197  * FUNCTION:    AcpiOsReleaseObject
 198  *
 199  * PARAMETERS:  Cache       - Handle to cache object
 200  *              Object      - The object to be released
 201  *
 202  * RETURN:      None
 203  *
 204  * DESCRIPTION: Release an object to the specified cache. If cache is full,
 205  *              the object is deleted.
 206  *
 207  ******************************************************************************/
 208
 209 ACPI_STATUS
 210 AcpiOsReleaseObject (
 211     ACPI_MEMORY_LIST        *Cache,
 212     void                    *Object)
 213 {
 214     ACPI_STATUS             Status;
 215
 216
 217     ACPI_FUNCTION_ENTRY ();
 218
 219
 220     if (!Cache || !Object)
 221     {
 222         return (AE_BAD_PARAMETER);
 223     }
 224
 225     /* If cache is full, just free this object */
 226
 227     if (Cache->CurrentDepth >= Cache->MaxDepth)
 228     {
 229         ACPI_FREE (Object);
 230         ACPI_MEM_TRACKING (Cache->TotalFreed++);
 231     }
 232
 233     /* Otherwise put this object back into the cache */
 234
 235     else
 236     {
 237         Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
 238         if (ACPI_FAILURE (Status))
 239         {
 240             return (Status);
 241         }
 242
 243         /* Mark the object as cached */
 244
 245         memset (Object, 0xCA, Cache->ObjectSize);
 246         ACPI_SET_DESCRIPTOR_TYPE (Object, ACPI_DESC_TYPE_CACHED);
 247
 248         /* Put the object at the head of the cache list */
 249
 250         ACPI_SET_DESCRIPTOR_PTR (Object, Cache->ListHead);
 251         Cache->ListHead = Object;
 252         Cache->CurrentDepth++;
 253
 254         (void) AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 255     }
 256
 257     return (AE_OK);
 258 }
 259
 260
 261 /*******************************************************************************
 262  *
 263  * FUNCTION:    AcpiOsAcquireObject
 264  *
 265  * PARAMETERS:  Cache           - Handle to cache object
 266  *
 267  * RETURN:      the acquired object. NULL on error
 268  *
 269  * DESCRIPTION: Get an object from the specified cache. If cache is empty,
 270  *              the object is allocated.
 271  *
 272  ******************************************************************************/
 273
 274 void *
 275 AcpiOsAcquireObject (
 276     ACPI_MEMORY_LIST        *Cache)
 277 {
 278     ACPI_STATUS             Status;
 279     void                    *Object;
 280
 281
 282     ACPI_FUNCTION_TRACE (OsAcquireObject);
 283
 284
 285     if (!Cache)
 286     {
 287         return_PTR (NULL);
 288     }
 289
 290     Status = AcpiUtAcquireMutex (ACPI_MTX_CACHES);
 291     if (ACPI_FAILURE (Status))
 292     {
 293         return_PTR (NULL);
 294     }
 295
 296     ACPI_MEM_TRACKING (Cache->Requests++);
 297
 298     /* Check the cache first */
 299
 300     if (Cache->ListHead)
 301     {
 302         /* There is an object available, use it */
 303
 304         Object = Cache->ListHead;
 305         Cache->ListHead = ACPI_GET_DESCRIPTOR_PTR (Object);
 306
 307         Cache->CurrentDepth--;
 308
 309         ACPI_MEM_TRACKING (Cache->Hits++);
 310         ACPI_DEBUG_PRINT_RAW ((ACPI_DB_EXEC,
 311             "%s: Object %p from %s cache\n",
 312             ACPI_GET_FUNCTION_NAME, Object, Cache->ListName));
 313
 314         Status = AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 315         if (ACPI_FAILURE (Status))
 316         {
 317             return_PTR (NULL);
 318         }
 319
 320         /* Clear (zero) the previously used Object */
 321
 322         memset (Object, 0, Cache->ObjectSize);
 323     }
 324     else
 325     {
 326         /* The cache is empty, create a new object */
 327
 328         ACPI_MEM_TRACKING (Cache->TotalAllocated++);
 329
 330 #ifdef ACPI_DBG_TRACK_ALLOCATIONS
 331         if ((Cache->TotalAllocated - Cache->TotalFreed) > Cache->MaxOccupied)
 332         {
 333             Cache->MaxOccupied = Cache->TotalAllocated - Cache->TotalFreed;
 334         }
 335 #endif
 336
 337         /* Avoid deadlock with ACPI_ALLOCATE_ZEROED */
 338
 339         Status = AcpiUtReleaseMutex (ACPI_MTX_CACHES);
 340         if (ACPI_FAILURE (Status))
 341         {
 342             return_PTR (NULL);
 343         }
 344
 345         Object = ACPI_ALLOCATE_ZEROED (Cache->ObjectSize);
 346         if (!Object)
 347         {
 348             return_PTR (NULL);
 349         }
 350     }
 351
 352     return_PTR (Object);
 353 }
 354 #endif /* ACPI_USE_LOCAL_CACHE */