More cache code, small fix in a comment.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@12951 27425a3e-05d8-49a3-a47f-9c15f0e5edd8

os/oslib/include/chobjcaches.h

@@ -1,5 +1,5 @@
 /*
-    ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio.
+    ChibiOS - Copyright (C) 2006..2019 Giovanni Di Sirio.
 
     This file is part of ChibiOS.
 
@@ -18,10 +18,10 @@
 */
 
 /**
- * @file    chcaches.h
+ * @file    chobjcaches.h
- * @brief   Caches macros and structures.
+ * @brief   Objects Caches macros and structures.
  *
- * @addtogroup oslib_chaches
+ * @addtogroup oslib_objchaches
  * @{
  */
 
@@ -34,6 +34,20 @@
 /* Module constants.                                                         */
 /*===========================================================================*/
 
+/**
+ * @name    Cached objects flags
+ * @{
+ */
+#define OC_FLAG_INVALID                     0x00000001U
+#define OC_FLAG_CACHEHIT                    0x00000002U
+#define OC_FLAG_ERROR                       0x00000004U
+/** @} */
+
+/**
+ * @brief   Identifier for an invalid group.
+ */
+#define OC_NO_GROUP                         0xFFFFFFFFU
+
 /*===========================================================================*/
 /* Module pre-compile time settings.                                         */
 /*===========================================================================*/
@@ -149,27 +163,45 @@ struct ch_oc_object {
    */
   oc_flags_t            obj_flags;
   /**
-   * @brief   Data part of the object.
+   * @brief   Pointer to the data part of the object.
+   * @note    This pointer must be initialized outside this module after
+   *          calling @p chCacheObjectInit() which sets it to @p NULL.
    */
-  uint8_t               data[];
+  void                  *data;
 };
 
 /**
  * @brief   Type of a cache object.
  */
 typedef struct {
+  /**
+   * @brief   Number of elements in the hash table.
+   */
+  size_t                hashn;
+  /**
+   * @brief   Pointer to the hash table.
+   */
+  oc_hash_header_t      *hashp;
+  /**
+   * @brief   Number of elements in the objects table.
+   */
+  size_t                objn;
+  /**
+   * @brief   Pointer to the objects table.
+   */
+  oc_object_t           *objp;
   /**
    * @brief   LRU list header.
    */
   oc_lru_header_t       lru;
+  /**
+   * @brief   Semaphore for cache access.
+   */
+  semaphore_t           cache_sem;
   /**
    * @brief   Semaphore for LRU access.
    */
   semaphore_t           lru_sem;
-  /**
-   * @brief   Size of the cached objects.
-   */
-  size_t                obj_size;
   /**
    * @brief   Reader functions for cached objects.
    */
@@ -192,16 +224,15 @@ typedef struct {
 extern "C" {
 #endif
   void chCacheObjectInit(objects_cache_t *ocp,
-                         size_t hashn,
+                         ucnt_t hashn,
                          oc_hash_header_t *hashp,
-                         size_t objn,
+                         ucnt_t objn,
                          oc_object_t *objp,
                          oc_readf_t readf,
                          oc_writef_t writef);
-  msg_t chCacheGetObject(objects_cache_t *ocp,
+  oc_object_t *chCacheGetObject(objects_cache_t *ocp,
                                 uint32_t group,
-                         uint32_t key,
+                                uint32_t key);
-                         oc_object_t **objpp);
   void chCacheReleaseObject(objects_cache_t *ocp,
                             oc_object_t *objp);
 #ifdef __cplusplus

os/oslib/src/chobjcaches.c

@@ -0,0 +1,190 @@
+/*
+    ChibiOS - Copyright (C) 2006..2019 Giovanni Di Sirio.
+
+    This file is part of ChibiOS.
+
+    ChibiOS is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    ChibiOS is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file    chobjcaches.c
+ * @brief   Objects Caches code.
+ * @details Byte pipes.
+ *          <h2>Operation mode</h2>
+ *          A pipe is an asynchronous communication mechanism.<br>
+ *          Operations defined for mailboxes:
+ *          - <b>Write</b>: Writes a buffer of data in the pipe in FIFO order.
+ *          - <b>Read</b>: A buffer of data is read from the read and removed.
+ *          - <b>Reset</b>: The pipe is emptied and all the stored data
+ *            is lost.
+ *          .
+ * @pre     In order to use the pipes APIs the @p CH_CFG_USE_PIPES
+ *          option must be enabled in @p chconf.h.
+ * @note    Compatible with RT and NIL.
+ *
+ * @addtogroup oslib_objchaches
+ * @{
+ */
+
+#include "ch.h"
+
+#if (CH_CFG_USE_OBJ_CACHES == TRUE) || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Module local definitions.                                                 */
+/*===========================================================================*/
+
+/* Default hash function.*/
+#if !defined(OC_HASH_FUNCTION) || defined(__DOXYGEN__)
+#define OC_HASH_FUNCTION(ocp, group, key)                                   \
+  (((unsigned)(group) + (unsigned)(key)) & ((unsigned)(ocp)->hashn - 1U))
+#endif
+
+/* Insertion into an hash slot list.*/
+#define HASH_INSERT(ocp, objp, group, key) {                                \
+  oc_hash_header_t *hhp;                                                    \
+  (hhp) = &(ocp)->hashp[OC_HASH_FUNCTION(ocp, group, key)];                 \
+  (objp)->hash_next = (hhp)->hash_next;                                     \
+  (objp)->hash_prev = (oc_object_t *)(hhp);                                 \
+  (hhp)->hash_next->hash_prev = (objp);                                     \
+  (hhp)->hash_next = (objp);                                                \
+}
+
+/* Insertion on LRU head (newer objects).*/
+#define LRU_INSERT_HEAD(ocp, objp) {                                        \
+  (objp)->lru_next = (ocp)->lru.lru_next;                                   \
+  (objp)->lru_prev = (oc_object_t *)&(ocp)->lru;                            \
+  (ocp)->lru.lru_next->lru_prev = (objp);                                   \
+  (ocp)->lru.lru_next = (objp);                                             \
+}
+
+/*===========================================================================*/
+/* Module exported variables.                                                */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local types.                                                       */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local variables.                                                   */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local functions.                                                   */
+/*===========================================================================*/
+
+static oc_object_t *oc_hash_get(objects_cache_t *ocp,
+                                uint32_t group,
+                                uint32_t key) {
+
+}
+
+/*===========================================================================*/
+/* Module exported functions.                                                */
+/*===========================================================================*/
+
+/**
+ * @brief   Initializes a @p objects_cache_t object.
+ *
+ * @param[out] ocp      pointer to the @p objects_cache_t structure to be
+ *                      initialized
+ * @param[in] hashn     number of elements in the hash table array, must be
+ *                      a power of two and not lower than @p objn
+ * @param[in] hashp     pointer to the hash table as an array of
+ *                      @p oc_hash_header_t
+ * @param[in] objn      number of elements in the objects table array
+ * @param[in] hashp     pointer to the hash objects as an array of
+ *                      @p oc_object_t
+ * @param[in] readf     pointer to an object reader function
+ * @param[in] writef    pointer to an object writer function
+ *
+ * @init
+ */
+void chCacheObjectInit(objects_cache_t *ocp,
+                       ucnt_t hashn,
+                       oc_hash_header_t *hashp,
+                       ucnt_t objn,
+                       oc_object_t *objp,
+                       oc_readf_t readf,
+                       oc_writef_t writef) {
+  unsigned i;
+
+  chDbgCheck((ocp != NULL) && (hashp != NULL) && (objp != NULL) &&
+             (hashn & (hashn - 1U) == 0U) &&
+             (objn > (size_t)0) && (hashn >= objn));
+
+  chSemObjectInit(&ocp->cache_sem, (cnt_t)1);
+  chSemObjectInit(&ocp->lru_sem, (cnt_t)objn);
+  ocp->hashn            = hashn;
+  ocp->hashp            = hashp;
+  ocp->objn             = objn;
+  ocp->objp             = objp;
+  ocp->readf            = readf;
+  ocp->writef           = writef;
+  ocp->lru.hash_next    = NULL;
+  ocp->lru.hash_prev    = NULL;
+  ocp->lru.lru_next     = (oc_object_t *)&ocp->lru;
+  ocp->lru.lru_prev     = (oc_object_t *)&ocp->lru;
+
+  /* Hash headers initialization.*/
+  while (hashp < &ocp->hashp[ocp->hashn]) {
+    hashp->hash_next = (oc_object_t *)hashp;
+    hashp->hash_prev = (oc_object_t *)hashp;
+  }
+
+  /* Object headers initialization.*/
+  while (objp < &ocp->objp[ocp->objn]) {
+    chSemObjectInit(&objp->obj_sem, (cnt_t)1);
+    HASH_INSERT(ocp, objp, OC_NO_GROUP, (uint32_t)i);
+    LRU_INSERT_HEAD(ocp, objp);
+    objp->obj_group = OC_NO_GROUP;
+    objp->obj_key   = 0U;
+    objp->obj_flags = OC_FLAG_INVALID;
+    objp->data      = NULL;
+  }
+}
+
+/**
+ * @brief   Retrieves an object from the cache.
+ * @note    If the object is not in cache then the returned object does
+ *          not specify the flag @p OC_FLAG_CACHEHIT meaning its data contains
+ *          garbage and must be initialized.
+ *
+ * @param[in] ocp       pointer to the @p objects_cache_t structure
+ * @param[in] group     object group identifier
+ * @param[in] key       object identifier within the group
+ * @return              The pointer to the retrieved object.
+ * @retval NULL         is a reserved value.
+ */
+oc_object_t *chCacheGetObject(objects_cache_t *ocp,
+                              uint32_t group,
+                              uint32_t key) {
+
+}
+
+/**
+ * @brief   Releases an object into the cache.
+ *
+ * @param[in] ocp       pointer to the @p objects_cache_t structure
+ * @param[in] objp      pointer to the @p oc_object_t structure
+ */
+void chCacheReleaseObject(objects_cache_t *ocp,
+                          oc_object_t *objp) {
+
+}
+
+#endif /* CH_CFG_USE_OBJ_CACHES == TRUE */
+
+/** @} */

os/oslib/src/chpipes.c

@@ -383,6 +383,6 @@ size_t chPipeReadTimeout(pipe_t *pp, uint8_t *bp,
   return max - n;
 }
 
-#endif /* CH_CFG_USE_MAILBOXES == TRUE */
+#endif /* CH_CFG_USE_PIPES == TRUE */
 
 /** @} */