From 641f2c372605cf405f0dda8536b45a78e0e5e2e2 Mon Sep 17 00:00:00 2001 From: Giovanni Di Sirio Date: Tue, 16 Feb 2016 09:59:21 +0000 Subject: Tree reorganization. git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@8899 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/common/oslib/src/chheap.c | 383 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 383 insertions(+) create mode 100644 os/common/oslib/src/chheap.c (limited to 'os/common/oslib/src/chheap.c') diff --git a/os/common/oslib/src/chheap.c b/os/common/oslib/src/chheap.c new file mode 100644 index 000000000..a35b646ba --- /dev/null +++ b/os/common/oslib/src/chheap.c @@ -0,0 +1,383 @@ +/* + ChibiOS - Copyright (C) 2006..2015 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 . +*/ + +/** + * @file chheap.c + * @brief Heaps code. + * + * @addtogroup heaps + * @details Heap Allocator related APIs. + *

Operation mode

+ * The heap allocator implements a first-fit strategy and its APIs + * are functionally equivalent to the usual @p malloc() and @p free() + * library functions. The main difference is that the OS heap APIs + * are guaranteed to be thread safe and there is the ability to + * return memory blocks aligned to arbitrary powers of two.
+ * @pre In order to use the heap APIs the @p CH_CFG_USE_HEAP option must + * be enabled in @p chconf.h. + * @note Compatible with RT and NIL. + * @{ + */ + +#include "ch.h" + +#if (CH_CFG_USE_HEAP == TRUE) || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Module local definitions. */ +/*===========================================================================*/ + +/* + * Defaults on the best synchronization mechanism available. + */ +#if (CH_CFG_USE_MUTEXES == TRUE) || defined(__DOXYGEN__) +#define H_LOCK(h) chMtxLock(&(h)->mtx) +#define H_UNLOCK(h) chMtxUnlock(&(h)->mtx) +#else +#define H_LOCK(h) (void) chSemWait(&(h)->sem) +#define H_UNLOCK(h) chSemSignal(&(h)->sem) +#endif + +#define H_BLOCK(hp) ((hp) + 1U) + +#define H_LIMIT(hp) (H_BLOCK(hp) + H_PAGES(hp)) + +#define H_NEXT(hp) ((hp)->free.next) + +#define H_PAGES(hp) ((hp)->free.pages) + +#define H_HEAP(hp) ((hp)->used.heap) + +#define H_SIZE(hp) ((hp)->used.size) + +/*===========================================================================*/ +/* Module exported variables. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module local types. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module local variables. */ +/*===========================================================================*/ + +/** + * @brief Default heap descriptor. + */ +static memory_heap_t default_heap; + +/*===========================================================================*/ +/* Module local functions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Module exported functions. */ +/*===========================================================================*/ + +/** + * @brief Initializes the default heap. + * + * @notapi + */ +void _heap_init(void) { + + default_heap.provider = chCoreAllocAligned; + H_NEXT(&default_heap.header) = NULL; + H_PAGES(&default_heap.header) = 0; +#if (CH_CFG_USE_MUTEXES == TRUE) || defined(__DOXYGEN__) + chMtxObjectInit(&default_heap.mtx); +#else + chSemObjectInit(&default_heap.sem, (cnt_t)1); +#endif +} + +/** + * @brief Initializes a memory heap from a static memory area. + * @pre Both the heap buffer base and the heap size must be aligned to + * the @p heap_header_t type size. + * + * @param[out] heapp pointer to the memory heap descriptor to be initialized + * @param[in] buf heap buffer base + * @param[in] size heap size + * + * @init + */ +void chHeapObjectInit(memory_heap_t *heapp, void *buf, size_t size) { + heap_header_t *hp = buf; + + chDbgCheck((heapp != NULL) && (size > 0U) && + MEM_IS_ALIGNED(buf, CH_HEAP_ALIGNMENT) && + MEM_IS_ALIGNED(size, CH_HEAP_ALIGNMENT)); + + heapp->provider = NULL; + H_NEXT(&heapp->header) = hp; + H_PAGES(&heapp->header) = 0; + H_NEXT(hp) = NULL; + H_PAGES(hp) = (size - sizeof (heap_header_t)) / CH_HEAP_ALIGNMENT; +#if (CH_CFG_USE_MUTEXES == TRUE) || defined(__DOXYGEN__) + chMtxObjectInit(&heapp->mtx); +#else + chSemObjectInit(&heapp->sem, (cnt_t)1); +#endif +} + +/** + * @brief Allocates a block of memory from the heap by using the first-fit + * algorithm. + * @details The allocated block is guaranteed to be properly aligned to the + * specified alignment. + * + * @param[in] heapp pointer to a heap descriptor or @p NULL in order to + * access the default heap. + * @param[in] size the size of the block to be allocated. Note that the + * allocated block may be a bit bigger than the requested + * size for alignment and fragmentation reasons. + * @param[in] align desired memory alignment + * @return A pointer to the aligned allocated block. + * @retval NULL if the block cannot be allocated. + * + * @api + */ +void *chHeapAllocAligned(memory_heap_t *heapp, size_t size, unsigned align) { + heap_header_t *qp, *hp; + size_t pages; + + chDbgCheck((size > 0U) && MEM_IS_VALID_ALIGNMENT(align)); + + /* If an heap is not specified then the default system header is used.*/ + if (heapp == NULL) { + heapp = &default_heap; + } + + /* Minimum alignment is constrained by the heap header structure size.*/ + if (align < CH_HEAP_ALIGNMENT) { + align = CH_HEAP_ALIGNMENT; + } + + /* Size is converted in number of elementary allocation units.*/ + pages = MEM_ALIGN_NEXT(size, CH_HEAP_ALIGNMENT) / CH_HEAP_ALIGNMENT; + + /* Taking heap mutex/semaphore.*/ + H_LOCK(heapp); + + /* Start of the free blocks list.*/ + qp = &heapp->header; + while (H_NEXT(qp) != NULL) { + heap_header_t *ahp; + + /* Next free block.*/ + hp = H_NEXT(qp); + + /* Pointer aligned to the requested alignment.*/ + ahp = (heap_header_t *)MEM_ALIGN_NEXT(H_BLOCK(hp), align) - 1U; + + if ((ahp < H_LIMIT(hp)) && (pages <= (size_t)(H_LIMIT(hp) - 1U - ahp))) { + /* The block is large enough to contain a correctly aligned area + of sufficient size.*/ + + if (ahp > hp) { + /* The block is not properly aligned, must split it.*/ + size_t bpages; + + bpages = H_LIMIT(hp) - H_BLOCK(ahp); + H_PAGES(hp) = ahp - H_BLOCK(hp); + if (bpages > pages) { + /* The block is bigger than required, must split the excess.*/ + heap_header_t *fp; + + /* Creating the excess block.*/ + fp = H_BLOCK(ahp) + pages; + H_PAGES(fp) = bpages - pages - 1U; + + /* Linking the excess block.*/ + H_NEXT(fp) = H_NEXT(hp); + H_NEXT(hp) = fp; + } + + hp = ahp; + } + else { + /* The block is already properly aligned.*/ + + if (H_PAGES(hp) == pages) { + /* Exact size, getting the whole block.*/ + H_NEXT(qp) = H_NEXT(hp); + } + else { + /* The block is bigger than required, must split the excess.*/ + heap_header_t *fp; + + fp = H_BLOCK(hp) + pages; + H_NEXT(fp) = H_NEXT(hp); + H_PAGES(fp) = H_LIMIT(hp) - H_BLOCK(fp); + H_NEXT(qp) = fp; + } + } + + /* Setting in the block owner heap and size.*/ + H_SIZE(hp) = size; + H_HEAP(hp) = heapp; + + /* Releasing heap mutex/semaphore.*/ + H_UNLOCK(heapp); + + /*lint -save -e9087 [11.3] Safe cast.*/ + return (void *)H_BLOCK(hp); + /*lint -restore*/ + } + + /* Next in the free blocks list.*/ + qp = hp; + } + + /* Releasing heap mutex/semaphore.*/ + H_UNLOCK(heapp); + + /* More memory is required, tries to get it from the associated provider + else fails.*/ + if (heapp->provider != NULL) { + hp = heapp->provider((pages + 1U) * CH_HEAP_ALIGNMENT, align); + if (hp != NULL) { + H_HEAP(hp) = heapp; + H_SIZE(hp) = size; + + /*lint -save -e9087 [11.3] Safe cast.*/ + return (void *)H_BLOCK(hp); + /*lint -restore*/ + } + } + + return NULL; +} + +/** + * @brief Frees a previously allocated memory block. + * + * @param[in] p pointer to the memory block to be freed + * + * @api + */ +void chHeapFree(void *p) { + heap_header_t *qp, *hp; + memory_heap_t *heapp; + + chDbgCheck((p != NULL) && MEM_IS_ALIGNED(p, CH_HEAP_ALIGNMENT)); + + /*lint -save -e9087 [11.3] Safe cast.*/ + hp = (heap_header_t *)p - 1U; + /*lint -restore*/ + heapp = H_HEAP(hp); + qp = &heapp->header; + + /* Size is converted in number of elementary allocation units.*/ + H_PAGES(hp) = MEM_ALIGN_NEXT(H_SIZE(hp), + CH_HEAP_ALIGNMENT) / CH_HEAP_ALIGNMENT; + + /* Taking heap mutex/semaphore.*/ + H_LOCK(heapp); + + while (true) { + chDbgAssert((hp < qp) || (hp >= H_LIMIT(qp)), "within free block"); + + if (((qp == &heapp->header) || (hp > qp)) && + ((H_NEXT(qp) == NULL) || (hp < H_NEXT(qp)))) { + /* Insertion after qp.*/ + H_NEXT(hp) = H_NEXT(qp); + H_NEXT(qp) = hp; + /* Verifies if the newly inserted block should be merged.*/ + if (H_LIMIT(hp) == H_NEXT(hp)) { + /* Merge with the next block.*/ + H_PAGES(hp) += H_PAGES(H_NEXT(hp)) + 1U; + H_NEXT(hp) = H_NEXT(H_NEXT(hp)); + } + if ((H_LIMIT(qp) == hp)) { + /* Merge with the previous block.*/ + H_PAGES(qp) += H_PAGES(hp) + 1U; + H_NEXT(qp) = H_NEXT(hp); + } + break; + } + qp = H_NEXT(qp); + } + + /* Releasing heap mutex/semaphore.*/ + H_UNLOCK(heapp); + + return; +} + +/** + * @brief Reports the heap status. + * @note This function is meant to be used in the test suite, it should + * not be really useful for the application code. + * + * @param[in] heapp pointer to a heap descriptor or @p NULL in order to + * access the default heap. + * @param[in] totalp pointer to a variable that will receive the total + * fragmented free space or @ NULL + * @param[in] largestp pointer to a variable that will receive the largest + * free free block found space or @ NULL + * @return The number of fragments in the heap. + * + * @api + */ +size_t chHeapStatus(memory_heap_t *heapp, size_t *totalp, size_t *largestp) { + heap_header_t *qp; + size_t n, tpages, lpages; + + if (heapp == NULL) { + heapp = &default_heap; + } + + H_LOCK(heapp); + tpages = 0U; + lpages = 0U; + n = 0U; + qp = &heapp->header; + while (H_NEXT(qp) != NULL) { + size_t pages = H_PAGES(H_NEXT(qp)); + + /* Updating counters.*/ + n++; + tpages += pages; + if (pages > lpages) { + lpages = pages; + } + + qp = H_NEXT(qp); + } + + /* Writing out fragmented free memory.*/ + if (totalp != NULL) { + *totalp = tpages * CH_HEAP_ALIGNMENT; + } + + /* Writing out unfragmented free memory.*/ + if (largestp != NULL) { + *largestp = lpages * CH_HEAP_ALIGNMENT; + } + H_UNLOCK(heapp); + + return n; +} + +#endif /* CH_CFG_USE_HEAP == TRUE */ + +/** @} */ -- cgit v1.2.3