[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/bsp/lk/lib/heap/cmpctmalloc/cmpctmalloc.c b/src/bsp/lk/lib/heap/cmpctmalloc/cmpctmalloc.c
new file mode 100644
index 0000000..2524949
--- /dev/null
+++ b/src/bsp/lk/lib/heap/cmpctmalloc/cmpctmalloc.c
@@ -0,0 +1,912 @@
+/*
+ * Copyright (c) 2015 Google, Inc. All rights reserved
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <debug.h>
+#include <trace.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <kernel/thread.h>
+#include <kernel/mutex.h>
+#include <kernel/spinlock.h>
+#include <lib/cmpctmalloc.h>
+#include <lib/heap.h>
+#include <lib/page_alloc.h>
+
+// Malloc implementation tuned for space.
+//
+// Allocation strategy takes place with a global mutex.  Freelist entries are
+// kept in linked lists with 8 different sizes per binary order of magnitude
+// and the header size is two words with eager coalescing on free.
+
+#ifdef DEBUG
+#define CMPCT_DEBUG
+#endif
+
+#define LOCAL_TRACE 0
+
+#define ALLOC_FILL 0x99
+#define FREE_FILL 0x77
+#define PADDING_FILL 0x55
+
+#if WITH_KERNEL_VM && !defined(HEAP_GROW_SIZE)
+#define HEAP_GROW_SIZE (1 * 1024 * 1024) /* Grow aggressively */
+#elif !defined(HEAP_GROW_SIZE)
+#define HEAP_GROW_SIZE (4 * 1024) /* Grow less aggressively */
+#endif
+
+STATIC_ASSERT(IS_PAGE_ALIGNED(HEAP_GROW_SIZE));
+
+// Individual allocations above 4Mbytes are just fetched directly from the
+// block allocator.
+#define HEAP_ALLOC_VIRTUAL_BITS 22
+
+// When we grow the heap we have to have somewhere in the freelist to put the
+// resulting freelist entry, so the freelist has to have a certain number of
+// buckets.
+STATIC_ASSERT(HEAP_GROW_SIZE <= (1u << HEAP_ALLOC_VIRTUAL_BITS));
+
+// Buckets for allocations.  The smallest 15 buckets are 8, 16, 24, etc. up to
+// 120 bytes.  After that we round up to the nearest size that can be written
+// /^0*1...0*$/, giving 8 buckets per order of binary magnitude.  The freelist
+// entries in a given bucket have at least the given size, plus the header
+// size.  On 64 bit, the 8 byte bucket is useless, since the freelist header
+// is 16 bytes larger than the header, but we have it for simplicity.
+#define NUMBER_OF_BUCKETS (1 + 15 + (HEAP_ALLOC_VIRTUAL_BITS - 7) * 8)
+
+// All individual memory areas on the heap start with this.
+typedef struct header_struct {
+    struct header_struct *left;  // Pointer to the previous area in memory order.
+    size_t size;
+} header_t;
+
+typedef struct free_struct {
+    header_t header;
+    struct free_struct *next;
+    struct free_struct *prev;
+} free_t;
+
+struct heap {
+    size_t size;
+    size_t remaining;
+    mutex_t lock;
+    free_t *free_lists[NUMBER_OF_BUCKETS];
+    // We have some 32 bit words that tell us whether there is an entry in the
+    // freelist.
+#define BUCKET_WORDS (((NUMBER_OF_BUCKETS) + 31) >> 5)
+    uint32_t free_list_bits[BUCKET_WORDS];
+};
+
+// Heap static vars.
+static struct heap theheap;
+
+static ssize_t heap_grow(size_t len, free_t **bucket);
+
+static void lock(void)
+{
+    mutex_acquire(&theheap.lock);
+}
+
+static void unlock(void)
+{
+    mutex_release(&theheap.lock);
+}
+
+static void dump_free(header_t *header)
+{
+    dprintf(INFO, "\t\tbase %p, end 0x%lx, len 0x%zx\n", header, (vaddr_t)header + header->size, header->size);
+}
+
+void cmpct_dump(void)
+{
+    lock();
+    dprintf(INFO, "Heap dump (using cmpctmalloc):\n");
+    dprintf(INFO, "\tsize %lu, remaining %lu\n",
+            (unsigned long)theheap.size,
+            (unsigned long)theheap.remaining);
+
+    dprintf(INFO, "\tfree list:\n");
+    for (int i = 0; i < NUMBER_OF_BUCKETS; i++) {
+        bool header_printed = false;
+        free_t *free_area = theheap.free_lists[i];
+        for (; free_area != NULL; free_area = free_area->next) {
+            ASSERT(free_area != free_area->next);
+            if (!header_printed) {
+                dprintf(INFO, "\tbucket %d\n", i);
+                header_printed = true;
+            }
+            dump_free(&free_area->header);
+        }
+    }
+    unlock();
+}
+
+// Operates in sizes that don't include the allocation header.
+static int size_to_index_helper(
+    size_t size, size_t *rounded_up_out, int adjust, int increment)
+{
+    // First buckets are simply 8-spaced up to 128.
+    if (size <= 128) {
+        if (sizeof(size_t) == 8u && size <= sizeof(free_t) - sizeof(header_t)) {
+            *rounded_up_out = sizeof(free_t) - sizeof(header_t);
+        } else {
+            *rounded_up_out = size;
+        }
+        // No allocation is smaller than 8 bytes, so the first bucket is for 8
+        // byte spaces (not including the header).  For 64 bit, the free list
+        // struct is 16 bytes larger than the header, so no allocation can be
+        // smaller than that (otherwise how to free it), but we have empty 8
+        // and 16 byte buckets for simplicity.
+        return (size >> 3) - 1;
+    }
+
+    // We are going to go up to the next size to round up, but if we hit a
+    // bucket size exactly we don't want to go up. By subtracting 8 here, we
+    // will do the right thing (the carry propagates up for the round numbers
+    // we are interested in).
+    size += adjust;
+    // After 128 the buckets are logarithmically spaced, every 16 up to 256,
+    // every 32 up to 512 etc.  This can be thought of as rows of 8 buckets.
+    // GCC intrinsic count-leading-zeros.
+    // Eg. 128-255 has 24 leading zeros and we want row to be 4.
+    unsigned row = sizeof(size_t) * 8 - 4 - __builtin_clzl(size);
+    // For row 4 we want to shift down 4 bits.
+    unsigned column = (size >> row) & 7;
+    int row_column = (row << 3) | column;
+    row_column += increment;
+    size = (8 + (row_column & 7)) << (row_column >> 3);
+    *rounded_up_out = size;
+    // We start with 15 buckets, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96,
+    // 104, 112, 120.  Then we have row 4, sizes 128 and up, with the
+    // row-column 8 and up.
+    int answer = row_column + 15 - 32;
+    DEBUG_ASSERT(answer < NUMBER_OF_BUCKETS);
+    return answer;
+}
+
+// Round up size to next bucket when allocating.
+static int size_to_index_allocating(size_t size, size_t *rounded_up_out)
+{
+    size_t rounded = ROUNDUP(size, 8);
+    return size_to_index_helper(rounded, rounded_up_out, -8, 1);
+}
+
+// Round down size to next bucket when freeing.
+static int size_to_index_freeing(size_t size)
+{
+    size_t dummy;
+    return size_to_index_helper(size, &dummy, 0, 0);
+}
+
+inline header_t *tag_as_free(void *left)
+{
+    return (header_t *)((uintptr_t)left | 1);
+}
+
+inline bool is_tagged_as_free(header_t *header)
+{
+    return ((uintptr_t)(header->left) & 1) != 0;
+}
+
+inline header_t *untag(void *left)
+{
+    return (header_t *)((uintptr_t)left & ~1);
+}
+
+inline header_t *right_header(header_t *header)
+{
+    return (header_t *)((char *)header + header->size);
+}
+
+inline static void set_free_list_bit(int index)
+{
+    theheap.free_list_bits[index >> 5] |= (1u << (31 - (index & 0x1f)));
+}
+
+inline static void clear_free_list_bit(int index)
+{
+    theheap.free_list_bits[index >> 5] &= ~(1u << (31 - (index & 0x1f)));
+}
+
+static int find_nonempty_bucket(int index)
+{
+    uint32_t mask = (1u << (31 - (index & 0x1f))) - 1;
+    mask = mask * 2 + 1;
+    mask &= theheap.free_list_bits[index >> 5];
+    if (mask != 0) return (index & ~0x1f) + __builtin_clz(mask);
+    for (index = ROUNDUP(index + 1, 32); index <= NUMBER_OF_BUCKETS; index += 32) {
+        mask = theheap.free_list_bits[index >> 5];
+        if (mask != 0u) return index + __builtin_clz(mask);
+    }
+    return -1;
+}
+
+static bool is_start_of_os_allocation(header_t *header)
+{
+    return header->left == untag(NULL);
+}
+
+static void create_free_area(void *address, void *left, size_t size, free_t **bucket)
+{
+    free_t *free_area = (free_t *)address;
+    free_area->header.size = size;
+    free_area->header.left = tag_as_free(left);
+    if (bucket == NULL) {
+        int index = size_to_index_freeing(size - sizeof(header_t));
+        set_free_list_bit(index);
+        bucket = &theheap.free_lists[index];
+    }
+    free_t *old_head = *bucket;
+    if (old_head != NULL) old_head->prev = free_area;
+    free_area->next = old_head;
+    free_area->prev = NULL;
+    *bucket = free_area;
+    theheap.remaining += size;
+#ifdef CMPCT_DEBUG
+    memset(free_area + 1, FREE_FILL, size - sizeof(free_t));
+#endif
+}
+
+static bool is_end_of_os_allocation(char *address)
+{
+    return ((header_t *)address)->size == 0;
+}
+
+static void free_to_os(header_t *header, size_t size)
+{
+    DEBUG_ASSERT(IS_PAGE_ALIGNED(size));
+    page_free(header, size >> PAGE_SIZE_SHIFT);
+    theheap.size -= size;
+}
+
+static void free_memory(void *address, void *left, size_t size)
+{
+    left = untag(left);
+    if (IS_PAGE_ALIGNED(left) &&
+            is_start_of_os_allocation(left) &&
+            is_end_of_os_allocation((char *)address + size)) {
+        free_to_os(left, size + ((header_t *)left)->size + sizeof(header_t));
+    } else {
+        create_free_area(address, left, size, NULL);
+    }
+}
+
+static void unlink_free(free_t *free_area, int bucket)
+{
+    theheap.remaining -= free_area->header.size;
+    ASSERT(theheap.remaining < 4000000000u);
+    free_t *next = free_area->next;
+    free_t *prev = free_area->prev;
+    if (theheap.free_lists[bucket] == free_area) {
+        theheap.free_lists[bucket] = next;
+        if (next == NULL) clear_free_list_bit(bucket);
+    }
+    if (prev != NULL) prev->next = next;
+    if (next != NULL) next->prev = prev;
+}
+
+static void unlink_free_unknown_bucket(free_t *free_area)
+{
+    return unlink_free(free_area, size_to_index_freeing(free_area->header.size - sizeof(header_t)));
+}
+
+static void *create_allocation_header(
+    void *address, size_t offset, size_t size, void *left)
+{
+    header_t *standalone = (header_t *)((char *)address + offset);
+    standalone->left = untag(left);
+    standalone->size = size;
+    return standalone + 1;
+}
+
+static void FixLeftPointer(header_t *right, header_t *new_left)
+{
+    int tag = (uintptr_t)right->left & 1;
+    right->left = (header_t *)(((uintptr_t)new_left & ~1) | tag);
+}
+
+static void WasteFreeMemory(void)
+{
+    while (theheap.remaining != 0) cmpct_alloc(1);
+}
+
+// If we just make a big allocation it gets rounded off.  If we actually
+// want to use a reasonably accurate amount of memory for test purposes, we
+// have to do many small allocations.
+static void *TestTrimHelper(ssize_t target)
+{
+   char *answer = NULL;
+   size_t remaining = theheap.remaining;
+   while (theheap.remaining - target > 512) {
+       char *next_block = cmpct_alloc(8 + ((theheap.remaining - target) >> 2));
+       *(char**)next_block = answer;
+       answer = next_block;
+       if (theheap.remaining > remaining) return answer;
+       // Abandon attemt to hit particular freelist entry size if we accidentally got more memory
+       // from the OS.
+       remaining = theheap.remaining;
+   }
+   return answer;
+}
+
+static void TestTrimFreeHelper(char *block)
+{
+    while (block) {
+        char *next_block = *(char **)block;
+        cmpct_free(block);
+        block = next_block;
+    }
+}
+
+static void cmpct_test_trim(void)
+{
+    WasteFreeMemory();
+
+    size_t test_sizes[200];
+    int sizes = 0;
+
+    for (size_t s = 1; s < PAGE_SIZE * 4; s = (s + 1) * 1.1) {
+        test_sizes[sizes++] = s;
+        ASSERT(sizes < 200);
+    }
+    for (ssize_t s = -32; s <= 32; s += 8) {
+        test_sizes[sizes++] = PAGE_SIZE + s;
+        ASSERT(sizes < 200);
+    }
+
+    // Test allocations at the start of an OS allocation.
+    for (int with_second_alloc = 0; with_second_alloc < 2; with_second_alloc++) {
+        for (int i = 0; i < sizes; i++) {
+            size_t s = test_sizes[i];
+
+            char *a, *a2 = NULL;
+            a = cmpct_alloc(s);
+            if (with_second_alloc) {
+                a2 = cmpct_alloc(1);
+                if (s < PAGE_SIZE >> 1) {
+                    // It is the intention of the test that a is at the start of an OS allocation
+                    // and that a2 is "right after" it.  Otherwise we are not testing what I
+                    // thought.  OS allocations are certainly not smaller than a page, so check in
+                    // that case.
+                    ASSERT((uintptr_t)(a2 - a) < s * 1.13 + 48);
+                }
+            }
+            cmpct_trim();
+            size_t remaining = theheap.remaining;
+            // We should have < 1 page on either side of the a allocation.
+            ASSERT(remaining < PAGE_SIZE * 2);
+            cmpct_free(a);
+            if (with_second_alloc) {
+                // Now only a2 is holding onto the OS allocation.
+                ASSERT(theheap.remaining > remaining);
+            } else {
+                ASSERT(theheap.remaining == 0);
+            }
+            remaining = theheap.remaining;
+            cmpct_trim();
+            ASSERT(theheap.remaining <= remaining);
+            // If a was at least one page then the trim should have freed up that page.
+            if (s >= PAGE_SIZE && with_second_alloc) ASSERT(theheap.remaining < remaining);
+            if (with_second_alloc) cmpct_free(a2);
+        }
+        ASSERT(theheap.remaining == 0);
+    }
+
+    ASSERT(theheap.remaining == 0);
+
+    // Now test allocations near the end of an OS allocation.
+    for (ssize_t wobble = -64; wobble <= 64; wobble += 8) {
+        for (int i = 0; i < sizes; i++) {
+            size_t s = test_sizes[i];
+
+            if ((ssize_t)s + wobble < 0) continue;
+
+            char *start_of_os_alloc = cmpct_alloc(1);
+
+            // If the OS allocations are very small this test does not make sense.
+            if (theheap.remaining <= s + wobble) {
+                cmpct_free(start_of_os_alloc);
+                continue;
+            }
+
+            char *big_bit_in_the_middle = TestTrimHelper(s + wobble);
+            size_t remaining = theheap.remaining;
+
+            // If the remaining is big we started a new OS allocation and the test
+            // makes no sense.
+            if (remaining > 128 + s * 1.13 + wobble) {
+                cmpct_free(start_of_os_alloc);
+                TestTrimFreeHelper(big_bit_in_the_middle);
+                continue;
+            }
+
+            cmpct_free(start_of_os_alloc);
+            remaining = theheap.remaining;
+
+            // This trim should sometimes trim a page off the end of the OS allocation.
+            cmpct_trim();
+            ASSERT(theheap.remaining <= remaining);
+            remaining = theheap.remaining;
+
+            // We should have < 1 page on either side of the big allocation.
+            ASSERT(remaining < PAGE_SIZE * 2);
+
+            TestTrimFreeHelper(big_bit_in_the_middle);
+        }
+    }
+}
+
+
+static void cmpct_test_buckets(void)
+{
+    size_t rounded;
+    unsigned bucket;
+    // Check for the 8-spaced buckets up to 128.
+    for (unsigned i = 1; i <= 128; i++) {
+        // Round up when allocating.
+        bucket = size_to_index_allocating(i, &rounded);
+        unsigned expected = (ROUNDUP(i, 8) >> 3) - 1;
+        ASSERT(bucket == expected);
+        ASSERT(IS_ALIGNED(rounded, 8));
+        ASSERT(rounded >= i);
+        if (i >= sizeof(free_t) - sizeof(header_t)) {
+            // Once we get above the size of the free area struct (4 words), we
+            // won't round up much for these small size.
+            ASSERT(rounded - i < 8);
+        }
+        // Only rounded sizes are freed.
+        if ((i & 7) == 0) {
+            // Up to size 128 we have exact buckets for each multiple of 8.
+            ASSERT(bucket == (unsigned)size_to_index_freeing(i));
+        }
+    }
+    int bucket_base = 7;
+    for (unsigned j = 16; j < 1024; j *= 2, bucket_base += 8) {
+        // Note the "<=", which ensures that we test the powers of 2 twice to ensure
+        // that both ways of calculating the bucket number match.
+        for (unsigned i = j * 8; i <= j * 16; i++) {
+            // Round up to j multiple in this range when allocating.
+            bucket = size_to_index_allocating(i, &rounded);
+            unsigned expected = bucket_base + ROUNDUP(i, j) / j;
+            ASSERT(bucket == expected);
+            ASSERT(IS_ALIGNED(rounded, j));
+            ASSERT(rounded >= i);
+            ASSERT(rounded - i < j);
+            // Only 8-rounded sizes are freed or chopped off the end of a free area
+            // when allocating.
+            if ((i & 7) == 0) {
+                // When freeing, if we don't hit the size of the bucket precisely,
+                // we have to put the free space into a smaller bucket, because
+                // the buckets have entries that will always be big enough for
+                // the corresponding allocation size (so we don't have to
+                // traverse the free chains to find a big enough one).
+                if ((i % j) == 0) {
+                    ASSERT((int)bucket == size_to_index_freeing(i));
+                } else {
+                    ASSERT((int)bucket - 1 == size_to_index_freeing(i));
+                }
+            }
+        }
+    }
+}
+
+static void cmpct_test_get_back_newly_freed_helper(size_t size)
+{
+    void *allocated = cmpct_alloc(size);
+    if (allocated == NULL) return;
+    char *allocated2 = cmpct_alloc(8);
+    char *expected_position = (char *)allocated + size;
+    if (allocated2 < expected_position || allocated2 > expected_position + 128) {
+        // If the allocated2 allocation is not in the same OS allocation as the
+        // first allocation then the test may not work as expected (the memory
+        // may be returned to the OS when we free the first allocation, and we
+        // might not get it back).
+        cmpct_free(allocated);
+        cmpct_free(allocated2);
+        return;
+    }
+
+    cmpct_free(allocated);
+    void *allocated3 = cmpct_alloc(size);
+    // To avoid churn and fragmentation we would want to get the newly freed
+    // memory back again when we allocate the same size shortly after.
+    ASSERT(allocated3 == allocated);
+    cmpct_free(allocated2);
+    cmpct_free(allocated3);
+}
+
+static void cmpct_test_get_back_newly_freed(void)
+{
+    size_t increment = 16;
+    for (size_t i = 128; i <= 0x8000000; i *= 2, increment *= 2) {
+        for (size_t j = i; j < i * 2; j += increment) {
+            cmpct_test_get_back_newly_freed_helper(i - 8);
+            cmpct_test_get_back_newly_freed_helper(i);
+            cmpct_test_get_back_newly_freed_helper(i + 1);
+        }
+    }
+    for (size_t i = 1024; i <= 2048; i++) {
+        cmpct_test_get_back_newly_freed_helper(i);
+    }
+}
+
+static void cmpct_test_return_to_os(void)
+{
+    cmpct_trim();
+    size_t remaining = theheap.remaining;
+    // This goes in a new OS allocation since the trim above removed any free
+    // area big enough to contain it.
+    void *a = cmpct_alloc(5000);
+    void *b = cmpct_alloc(2500);
+    cmpct_free(a);
+    cmpct_free(b);
+    // If things work as expected the new allocation is at the start of an OS
+    // allocation.  There's just one sentinel and one header to the left of it.
+    // It that's not the case then the allocation was met from some space in
+    // the middle of an OS allocation, and our test won't work as expected, so
+    // bail out.
+    if (((uintptr_t)a & (PAGE_SIZE - 1)) != sizeof(header_t) * 2) return;
+    // No trim needed when the entire OS allocation is free.
+    ASSERT(remaining == theheap.remaining);
+}
+
+void cmpct_test(void)
+{
+    cmpct_test_buckets();
+    cmpct_test_get_back_newly_freed();
+    cmpct_test_return_to_os();
+    cmpct_test_trim();
+    cmpct_dump();
+    void *ptr[16];
+
+    ptr[0] = cmpct_alloc(8);
+    ptr[1] = cmpct_alloc(32);
+    ptr[2] = cmpct_alloc(7);
+    cmpct_trim();
+    ptr[3] = cmpct_alloc(0);
+    ptr[4] = cmpct_alloc(98713);
+    ptr[5] = cmpct_alloc(16);
+
+    cmpct_free(ptr[5]);
+    cmpct_free(ptr[1]);
+    cmpct_free(ptr[3]);
+    cmpct_free(ptr[0]);
+    cmpct_free(ptr[4]);
+    cmpct_free(ptr[2]);
+
+    cmpct_dump();
+    cmpct_trim();
+    cmpct_dump();
+
+    int i;
+    for (i=0; i < 16; i++)
+        ptr[i] = 0;
+
+    for (i=0; i < 32768; i++) {
+        unsigned int index = (unsigned int)rand() % 16;
+
+        if ((i % (16*1024)) == 0)
+            printf("pass %d\n", i);
+
+//      printf("index 0x%x\n", index);
+        if (ptr[index]) {
+//          printf("freeing ptr[0x%x] = %p\n", index, ptr[index]);
+            cmpct_free(ptr[index]);
+            ptr[index] = 0;
+        }
+        unsigned int align = 1 << ((unsigned int)rand() % 8);
+        ptr[index] = cmpct_memalign((unsigned int)rand() % 32768, align);
+//      printf("ptr[0x%x] = %p, align 0x%x\n", index, ptr[index], align);
+
+        DEBUG_ASSERT(((addr_t)ptr[index] % align) == 0);
+//      cmpct_dump();
+    }
+
+    for (i=0; i < 16; i++) {
+        if (ptr[i])
+            cmpct_free(ptr[i]);
+    }
+
+    cmpct_dump();
+}
+
+static void *large_alloc(size_t size)
+{
+#ifdef CMPCT_DEBUG
+    size_t requested_size = size;
+#endif
+    size = ROUNDUP(size, 8);
+    free_t *free_area = NULL;
+    lock();
+    heap_grow(size, &free_area);
+    void *result =
+        create_allocation_header(free_area, 0, free_area->header.size, free_area->header.left);
+    // Normally the 'remaining free space' counter would be decremented when we
+    // unlink the free area from its bucket.  However in this case the free
+    // area was too big to go in any bucket and we had it in our own
+    // "free_area" variable so there is no unlinking and we have to adjust the
+    // counter here.
+    theheap.remaining -= free_area->header.size;
+    unlock();
+#ifdef CMPCT_DEBUG
+    memset(result, ALLOC_FILL, requested_size);
+    memset((char *)result + requested_size, PADDING_FILL, free_area->header.size - requested_size);
+#endif
+    return result;
+}
+
+void cmpct_trim(void)
+{
+    // Look at free list entries that are at least as large as one page plus a
+    // header. They might be at the start or the end of a block, so we can trim
+    // them and free the page(s).
+    lock();
+    for (int bucket = size_to_index_freeing(PAGE_SIZE);
+            bucket < NUMBER_OF_BUCKETS;
+            bucket++) {
+        free_t * next;
+        for (free_t *free_area = theheap.free_lists[bucket];
+                free_area != NULL;
+                free_area = next) {
+            DEBUG_ASSERT(free_area->header.size >= PAGE_SIZE + sizeof(header_t));
+            next = free_area->next;
+            header_t *right = right_header(&free_area->header);
+            if (is_end_of_os_allocation((char *)right)) {
+                char *old_os_allocation_end = (char *)ROUNDUP((uintptr_t)right, PAGE_SIZE);
+                // The page will end with a smaller free list entry and a header-sized sentinel.
+                char *new_os_allocation_end = (char *)
+                    ROUNDUP((uintptr_t)free_area + sizeof(header_t) + sizeof(free_t), PAGE_SIZE);
+                size_t freed_up = old_os_allocation_end - new_os_allocation_end;
+                DEBUG_ASSERT(IS_PAGE_ALIGNED(freed_up));
+                // Rare, because we only look at large freelist entries, but unlucky rounding
+                // could mean we can't actually free anything here.
+                if (freed_up == 0) continue;
+                unlink_free(free_area, bucket);
+                size_t new_free_size = free_area->header.size - freed_up;
+                DEBUG_ASSERT(new_free_size >= sizeof(free_t));
+                // Right sentinel, not free, stops attempts to coalesce right.
+                create_allocation_header(free_area, new_free_size, 0, free_area);
+                // Also puts it in the correct bucket.
+                create_free_area(free_area, untag(free_area->header.left), new_free_size, NULL);
+                page_free(new_os_allocation_end, freed_up >> PAGE_SIZE_SHIFT);
+                theheap.size -= freed_up;
+            } else if (is_start_of_os_allocation(untag(free_area->header.left))) {
+                char *old_os_allocation_start =
+                    (char *)ROUNDDOWN((uintptr_t)free_area, PAGE_SIZE);
+                // For the sentinel, we need at least one header-size of space between the page
+                // edge and the first allocation to the right of the free area.
+                char *new_os_allocation_start =
+                    (char *)ROUNDDOWN((uintptr_t)(right - 1), PAGE_SIZE);
+                size_t freed_up = new_os_allocation_start - old_os_allocation_start;
+                DEBUG_ASSERT(IS_PAGE_ALIGNED(freed_up));
+                // This should not happen because we only look at the large free list buckets.
+                if (freed_up == 0) continue;
+                unlink_free(free_area, bucket);
+                size_t sentinel_size = sizeof(header_t);
+                size_t new_free_size = free_area->header.size - freed_up;
+                if (new_free_size < sizeof(free_t)) {
+                    sentinel_size += new_free_size;
+                    new_free_size = 0;
+                }
+                // Left sentinel, not free, stops attempts to coalesce left.
+                create_allocation_header(new_os_allocation_start, 0, sentinel_size, NULL);
+                if (new_free_size == 0) {
+                    FixLeftPointer(right, (header_t *)new_os_allocation_start);
+                } else {
+                    DEBUG_ASSERT(new_free_size >= sizeof(free_t));
+                    char *new_free = new_os_allocation_start + sentinel_size;
+                    // Also puts it in the correct bucket.
+                    create_free_area(new_free, new_os_allocation_start, new_free_size, NULL);
+                    FixLeftPointer(right, (header_t *)new_free);
+                }
+                page_free(old_os_allocation_start, freed_up >> PAGE_SIZE_SHIFT);
+                theheap.size -= freed_up;
+            }
+        }
+    }
+    unlock();
+}
+
+void *cmpct_alloc(size_t size)
+{
+    if (size == 0u) return NULL;
+
+    if (size + sizeof(header_t) > (1u << HEAP_ALLOC_VIRTUAL_BITS)) return large_alloc(size);
+
+    size_t rounded_up;
+    int start_bucket = size_to_index_allocating(size, &rounded_up);
+
+    rounded_up += sizeof(header_t);
+
+    lock();
+    int bucket = find_nonempty_bucket(start_bucket);
+    if (bucket == -1) {
+        // Grow heap by at least 12% if we can.
+        size_t growby = MIN(1u << HEAP_ALLOC_VIRTUAL_BITS,
+                            MAX(theheap.size >> 3,
+                                MAX(HEAP_GROW_SIZE, rounded_up)));
+        while (heap_grow(growby, NULL) < 0) {
+            if (growby <= rounded_up) {
+                unlock();
+                return NULL;
+            }
+            growby = MAX(growby >> 1, rounded_up);
+        }
+        bucket = find_nonempty_bucket(start_bucket);
+    }
+    free_t *head = theheap.free_lists[bucket];
+    size_t left_over = head->header.size - rounded_up;
+    // We can't carve off the rest for a new free space if it's smaller than the
+    // free-list linked structure.  We also don't carve it off if it's less than
+    // 1.6% the size of the allocation.  This is to avoid small long-lived
+    // allocations being placed right next to large allocations, hindering
+    // coalescing and returning pages to the OS.
+    if (left_over >= sizeof(free_t) && left_over > (size >> 6)) {
+        header_t *right = right_header(&head->header);
+        unlink_free(head, bucket);
+        void *free = (char *)head + rounded_up;
+        create_free_area(free, head, left_over, NULL);
+        FixLeftPointer(right, (header_t *)free);
+        head->header.size -= left_over;
+    } else {
+        unlink_free(head, bucket);
+    }
+    void *result =
+        create_allocation_header(head, 0, head->header.size, head->header.left);
+#ifdef CMPCT_DEBUG
+    memset(result, ALLOC_FILL, size);
+    memset(((char *)result) + size, PADDING_FILL, rounded_up - size - sizeof(header_t));
+#endif
+    unlock();
+    return result;
+}
+
+void *cmpct_memalign(size_t size, size_t alignment)
+{
+    if (alignment < 8) return cmpct_alloc(size);
+    size_t padded_size =
+        size + alignment + sizeof(free_t) + sizeof(header_t);
+    char *unaligned = (char *)cmpct_alloc(padded_size);
+    lock();
+    size_t mask = alignment - 1;
+    uintptr_t payload_int = (uintptr_t)unaligned + sizeof(free_t) +
+                            sizeof(header_t) + mask;
+    char *payload = (char *)(payload_int & ~mask);
+    if (unaligned != payload) {
+        header_t *unaligned_header = (header_t *)unaligned - 1;
+        header_t *header = (header_t *)payload - 1;
+        size_t left_over = payload - unaligned;
+        create_allocation_header(
+            header, 0, unaligned_header->size - left_over, unaligned_header);
+        header_t *right = right_header(unaligned_header);
+        unaligned_header->size = left_over;
+        FixLeftPointer(right, header);
+        unlock();
+        cmpct_free(unaligned);
+    } else {
+        unlock();
+    }
+    // TODO: Free the part after the aligned allocation.
+    return payload;
+}
+
+void cmpct_free(void *payload)
+{
+    if (payload == NULL) return;
+    header_t *header = (header_t *)payload - 1;
+    DEBUG_ASSERT(!is_tagged_as_free(header));  // Double free!
+    size_t size = header->size;
+    lock();
+    header_t *left = header->left;
+    if (left != NULL && is_tagged_as_free(left)) {
+        // Coalesce with left free object.
+        unlink_free_unknown_bucket((free_t *)left);
+        header_t *right = right_header(header);
+        if (is_tagged_as_free(right)) {
+            // Coalesce both sides.
+            unlink_free_unknown_bucket((free_t *)right);
+            header_t *right_right = right_header(right);
+            FixLeftPointer(right_right, left);
+            free_memory(left, left->left, left->size + size + right->size);
+        } else {
+            // Coalesce only left.
+            FixLeftPointer(right, left);
+            free_memory(left, left->left, left->size + size);
+        }
+    } else {
+        header_t *right = right_header(header);
+        if (is_tagged_as_free(right)) {
+            // Coalesce only right.
+            header_t *right_right = right_header(right);
+            unlink_free_unknown_bucket((free_t *)right);
+            FixLeftPointer(right_right, header);
+            free_memory(header, left, size + right->size);
+        } else {
+            free_memory(header, left, size);
+        }
+    }
+    unlock();
+}
+
+void *cmpct_realloc(void *payload, size_t size)
+{
+    if (payload == NULL) return cmpct_alloc(size);
+    header_t *header = (header_t *)payload - 1;
+    size_t old_size = header->size - sizeof(header_t);
+    void *new_payload = cmpct_alloc(size);
+    memcpy(new_payload, payload, MIN(size, old_size));
+    cmpct_free(payload);
+    return new_payload;
+}
+
+static void add_to_heap(void *new_area, size_t size, free_t **bucket)
+{
+    void *top = (char *)new_area + size;
+    header_t *left_sentinel = (header_t *)new_area;
+    // Not free, stops attempts to coalesce left.
+    create_allocation_header(left_sentinel, 0, sizeof(header_t), NULL);
+    header_t *new_header = left_sentinel + 1;
+    size_t free_size = size - 2 * sizeof(header_t);
+    create_free_area(new_header, left_sentinel, free_size, bucket);
+    header_t *right_sentinel = (header_t *)(top - sizeof(header_t));
+    // Not free, stops attempts to coalesce right.
+    create_allocation_header(right_sentinel, 0, 0, new_header);
+}
+
+// Create a new free-list entry of at least size bytes (including the
+// allocation header).  Called with the lock, apart from during init.
+static ssize_t heap_grow(size_t size, free_t **bucket)
+{
+    // The new free list entry will have a header on each side (the
+    // sentinels) so we need to grow the gross heap size by this much more.
+    size += 2 * sizeof(header_t);
+    size = ROUNDUP(size, PAGE_SIZE);
+    void *ptr = page_alloc(size >> PAGE_SIZE_SHIFT);
+    theheap.size += size;
+    if (ptr == NULL) return -1;
+    LTRACEF("growing heap by 0x%zx bytes, new ptr %p\n", size, ptr);
+    add_to_heap(ptr, size, bucket);
+    return size;
+}
+
+void cmpct_init(void)
+{
+    LTRACE_ENTRY;
+
+    // Create a mutex.
+    mutex_init(&theheap.lock);
+
+    // Initialize the free list.
+    for (int i = 0; i < NUMBER_OF_BUCKETS; i++) {
+        theheap.free_lists[i] = NULL;
+    }
+    for (int i = 0; i < BUCKET_WORDS; i++) {
+        theheap.free_list_bits[i] = 0;
+    }
+
+    size_t initial_alloc = HEAP_GROW_SIZE - 2 * sizeof(header_t);
+
+    theheap.remaining = 0;
+
+    heap_grow(initial_alloc, NULL);
+}
diff --git a/src/bsp/lk/lib/heap/cmpctmalloc/include/lib/cmpctmalloc.h b/src/bsp/lk/lib/heap/cmpctmalloc/include/lib/cmpctmalloc.h
new file mode 100644
index 0000000..11a4010
--- /dev/null
+++ b/src/bsp/lk/lib/heap/cmpctmalloc/include/lib/cmpctmalloc.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2015 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#pragma once
+
+#include <compiler.h>
+
+__BEGIN_CDECLS;
+
+void *cmpct_alloc(size_t);
+void *cmpct_realloc(void *, size_t);
+void cmpct_free(void *);
+void *cmpct_memalign(size_t size, size_t alignment);
+
+void cmpct_init(void);
+void cmpct_dump(void);
+void cmpct_test(void);
+void cmpct_trim(void);
+
+__END_CDECLS;
diff --git a/src/bsp/lk/lib/heap/cmpctmalloc/rules.mk b/src/bsp/lk/lib/heap/cmpctmalloc/rules.mk
new file mode 100644
index 0000000..9a4451d
--- /dev/null
+++ b/src/bsp/lk/lib/heap/cmpctmalloc/rules.mk
@@ -0,0 +1,8 @@
+LOCAL_DIR := $(GET_LOCAL_DIR)
+
+MODULE := $(LOCAL_DIR)
+
+MODULE_SRCS += \
+	$(LOCAL_DIR)/cmpctmalloc.c
+
+include make/module.mk