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-rw-r--r--lib/librte_malloc/malloc_elem.c280
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diff --git a/lib/librte_malloc/malloc_elem.c b/lib/librte_malloc/malloc_elem.c
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+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2012 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+#include <stdint.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <sys/queue.h>
+
+#include <rte_memory.h>
+#include <rte_memzone.h>
+#include <rte_tailq.h>
+#include <rte_eal.h>
+#include <rte_launch.h>
+#include <rte_per_lcore.h>
+#include <rte_lcore.h>
+#include <rte_debug.h>
+#include <rte_common.h>
+#include <rte_spinlock.h>
+
+#include "malloc_elem.h"
+#include "malloc_heap.h"
+
+#define MIN_DATA_SIZE (CACHE_LINE_SIZE * 2)
+
+/*
+ * initialise a general malloc_elem header structure
+ */
+void
+malloc_elem_init(struct malloc_elem *elem,
+ struct malloc_heap *heap, size_t size)
+{
+ elem->heap = heap;
+ elem->prev = elem->next_free = NULL;
+ elem->state = ELEM_FREE;
+ elem->size = size;
+ elem->pad = 0;
+ set_header(elem);
+ set_trailer(elem);
+}
+
+/*
+ * initialise a dummy malloc_elem header for the end-of-memzone marker
+ */
+void
+malloc_elem_mkend(struct malloc_elem *elem, struct malloc_elem *prev)
+{
+ malloc_elem_init(elem, prev->heap, 0);
+ elem->prev = prev;
+ elem->state = ELEM_BUSY; /* mark busy so its never merged */
+}
+
+/*
+ * calculate the starting point of where data of the requested size
+ * and alignment would fit in the current element. If the data doesn't
+ * fit, return NULL.
+ */
+static void *
+elem_start_pt(struct malloc_elem *elem, size_t size, unsigned align)
+{
+ const uintptr_t end_pt = (uintptr_t)elem +
+ elem->size - MALLOC_ELEM_TRAILER_LEN;
+ const uintptr_t new_data_start = rte_align_floor_int((end_pt - size),align);
+ const uintptr_t new_elem_start = new_data_start - MALLOC_ELEM_HEADER_LEN;
+
+ /* if the new start point is before the exist start, it won't fit */
+ return (new_elem_start < (uintptr_t)elem) ? NULL : (void *)new_elem_start;
+}
+
+/*
+ * use elem_start_pt to determine if we get meet the size and
+ * alignment request from the current element
+ */
+int
+malloc_elem_can_hold(struct malloc_elem *elem, size_t size, unsigned align)
+{
+ return elem_start_pt(elem, size, align) != NULL;
+}
+
+/*
+ * split an existing element into two smaller elements at the given
+ * split_pt parameter.
+ */
+static void
+split_elem(struct malloc_elem *elem, struct malloc_elem *split_pt)
+{
+ struct malloc_elem *next_elem = RTE_PTR_ADD(elem, elem->size);
+ const unsigned old_elem_size = (uintptr_t)split_pt - (uintptr_t)elem;
+ const unsigned new_elem_size = elem->size - old_elem_size;
+
+ malloc_elem_init(split_pt, elem->heap, new_elem_size);
+ split_pt->prev = elem;
+ next_elem->prev = split_pt;
+ elem->size = old_elem_size;
+ set_trailer(elem);
+}
+
+/*
+ * reserve a block of data in an existing malloc_elem. If the malloc_elem
+ * is much larger than the data block requested, we split the element in two.
+ * This function is only called from malloc_heap_alloc so parameter checking
+ * is not done here, as it's done there previously.
+ */
+struct malloc_elem *
+malloc_elem_alloc(struct malloc_elem *elem, size_t size,
+ unsigned align, struct malloc_elem *prev_free)
+{
+ struct malloc_elem *new_elem = elem_start_pt(elem, size, align);
+ const unsigned old_elem_size = (uintptr_t)new_elem - (uintptr_t)elem;
+
+ if (old_elem_size <= MALLOC_ELEM_OVERHEAD + MIN_DATA_SIZE){
+ /* don't split it, pad the element instead */
+ elem->state = ELEM_BUSY;
+ elem->pad = old_elem_size;
+
+ /* put a dummy header in padding, to point to real element header */
+ if (elem->pad > 0){ /* pad will be at least 64-bytes, as everything
+ * is cache-line aligned */
+ new_elem->pad = elem->pad;
+ new_elem->state = ELEM_PAD;
+ new_elem->size = elem->size - elem->pad;
+ set_header(new_elem);
+ }
+ /* remove element from free list */
+ if (prev_free == NULL)
+ elem->heap->free_head = elem->next_free;
+ else
+ prev_free->next_free = elem->next_free;
+
+ return new_elem;
+ }
+
+ /* we are going to split the element in two. The original element
+ * remains free, and the new element is the one allocated, so no free list
+ * changes need to be made.
+ */
+ split_elem(elem, new_elem);
+ new_elem->state = ELEM_BUSY;
+
+ return new_elem;
+}
+
+/*
+ * joing two struct malloc_elem together. elem1 and elem2 must
+ * be contiguous in memory.
+ */
+static inline void
+join_elem(struct malloc_elem *elem1, struct malloc_elem *elem2)
+{
+ struct malloc_elem *next = RTE_PTR_ADD(elem2, elem2->size);
+ elem1->size += elem2->size;
+ next->prev = elem1;
+}
+
+/*
+ * scan the free list, and remove the request element from that
+ * free list. (Free list to scan is got from heap pointer in element)
+ */
+static inline void
+remove_from_free_list(struct malloc_elem *elem)
+{
+ if (elem == elem->heap->free_head)
+ elem->heap->free_head = elem->next_free;
+ else{
+ struct malloc_elem *prev_free = elem->heap->free_head;
+ while (prev_free && prev_free->next_free != elem)
+ prev_free = prev_free->next_free;
+ if (!prev_free)
+ rte_panic("Corrupted free list\n");
+ prev_free->next_free = elem->next_free;
+ }
+}
+
+/*
+ * free a malloc_elem block by adding it to the free list. If the
+ * blocks either immediately before or immediately after newly freed block
+ * are also free, the blocks are merged together.
+ */
+int
+malloc_elem_free(struct malloc_elem *elem)
+{
+ if (!malloc_elem_cookies_ok(elem) || elem->state != ELEM_BUSY)
+ return -1;
+
+ rte_spinlock_lock(&(elem->heap->lock));
+ struct malloc_elem *next = RTE_PTR_ADD(elem, elem->size);
+ if (next->state == ELEM_FREE){
+ /* join to this one, and remove from free list */
+ join_elem(elem, next);
+ remove_from_free_list(next);
+ }
+
+ /* check if previous element is free, if so join with it and return,
+ * no need to update free list, as that element is already there
+ */
+ if (elem->prev != NULL && elem->prev->state == ELEM_FREE)
+ join_elem(elem->prev, elem);
+ /* otherwise add ourselves to the free list */
+ else {
+ elem->next_free = elem->heap->free_head;
+ elem->heap->free_head = elem;
+ elem->state = ELEM_FREE;
+ elem->pad = 0;
+ }
+ rte_spinlock_unlock(&(elem->heap->lock));
+ return 0;
+}
+
+/*
+ * attempt to resize a malloc_elem by expanding into any free space
+ * immediately after it in memory.
+ */
+int
+malloc_elem_resize(struct malloc_elem *elem, size_t size)
+{
+ const size_t new_size = size + MALLOC_ELEM_OVERHEAD;
+ /* if we request a smaller size, then always return ok */
+ const size_t current_size = elem->size - elem->pad;
+ if (current_size >= new_size)
+ return 0;
+
+ struct malloc_elem *next = RTE_PTR_ADD(elem, elem->size);
+ rte_spinlock_lock(&elem->heap->lock);
+ if (next ->state != ELEM_FREE)
+ goto err_return;
+ if (current_size + next->size < new_size)
+ goto err_return;
+
+ /* we now know the element fits, so join the two, then remove from free
+ * list
+ */
+ join_elem(elem, next);
+ remove_from_free_list(next);
+
+ if (elem->size - new_size > MIN_DATA_SIZE + MALLOC_ELEM_OVERHEAD){
+ /* now we have a big block together. Lets cut it down a bit, by splitting */
+ struct malloc_elem *split_pt = RTE_PTR_ADD(elem, new_size);
+ split_pt = RTE_ALIGN_CEIL(split_pt, CACHE_LINE_SIZE);
+ split_elem(elem, split_pt);
+ split_pt->state = ELEM_FREE;
+ split_pt->next_free = elem->heap->free_head;
+ elem->heap->free_head = split_pt;
+ }
+ rte_spinlock_unlock(&elem->heap->lock);
+ return 0;
+
+err_return:
+ rte_spinlock_unlock(&elem->heap->lock);
+ return -1;
+}