darling-bmalloc/bmalloc/PerProcess.cpp
2023-04-27 08:59:12 -07:00

92 lines
3.2 KiB
C++

/*
* Copyright (C) 2018 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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.
*/
#include "PerProcess.h"
#include "VMAllocate.h"
#include <stdio.h>
namespace bmalloc {
static constexpr unsigned tableSize = 100;
static constexpr bool verbose = false;
static Mutex s_mutex;
static char* s_bumpBase;
static size_t s_bumpOffset;
static size_t s_bumpLimit;
static PerProcessData* s_table[tableSize];
// Returns zero-filled memory by virtual of using vmAllocate.
static void* allocate(size_t size, size_t alignment)
{
s_bumpOffset = roundUpToMultipleOf(alignment, s_bumpOffset);
void* result = s_bumpBase + s_bumpOffset;
s_bumpOffset += size;
if (s_bumpOffset <= s_bumpLimit)
return result;
size_t allocationSize = vmSize(size);
void* allocation = vmAllocate(allocationSize);
s_bumpBase = static_cast<char*>(allocation);
s_bumpOffset = 0;
s_bumpLimit = allocationSize;
return allocate(size, alignment);
}
PerProcessData* getPerProcessData(unsigned hash, const char* disambiguator, size_t size, size_t alignment)
{
LockHolder lock(s_mutex);
PerProcessData*& bucket = s_table[hash % tableSize];
for (PerProcessData* data = bucket; data; data = data->next) {
if (!strcmp(data->disambiguator, disambiguator)) {
if (verbose)
fprintf(stderr, "%d: Using existing %s\n", getpid(), disambiguator);
RELEASE_BASSERT(data->size == size);
RELEASE_BASSERT(data->alignment == alignment);
return data;
}
}
if (verbose)
fprintf(stderr, "%d: Creating new %s\n", getpid(), disambiguator);
void* rawDataPtr = allocate(sizeof(PerProcessData), std::alignment_of<PerProcessData>::value);
PerProcessData* data = static_cast<PerProcessData*>(rawDataPtr);
data->disambiguator = disambiguator;
data->memory = allocate(size, alignment);
data->size = size;
data->alignment = alignment;
data->next = bucket;
bucket = data;
return data;
}
} // namespace bmalloc