darling-bmalloc/bmalloc/IsoDeallocatorInlines.h
2023-04-27 08:59:12 -07:00

85 lines
3.0 KiB
C++

/*
* Copyright (C) 2017 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.
*/
#pragma once
#include "BInline.h"
#include "IsoDeallocator.h"
#include "IsoPage.h"
#include "IsoSharedPage.h"
#include "Mutex.h"
#include <mutex>
namespace bmalloc {
template<typename Config>
IsoDeallocator<Config>::IsoDeallocator(Mutex& lock)
: m_lock(&lock)
{
}
template<typename Config>
IsoDeallocator<Config>::~IsoDeallocator()
{
}
template<typename Config>
template<typename Type>
void IsoDeallocator<Config>::deallocate(api::IsoHeap<Type>& handle, void* ptr)
{
static constexpr bool verbose = false;
if (verbose)
fprintf(stderr, "%p: deallocating %p of size %u\n", &IsoPage<Config>::pageFor(ptr)->heap(), ptr, Config::objectSize);
// For allocation from shared pages, we deallocate immediately rather than batching deallocations with object log.
// The batching delays the reclamation of the shared cells, which can make allocator mistakenly think that "we exhaust shared
// cells because this is allocated a lot". Since the number of shared cells are limited, this immediate deallocation path
// should be rarely taken. If we see frequent malloc-and-free pattern, we tier up the allocator from shared mode to fast mode.
IsoPageBase* page = IsoPageBase::pageFor(ptr);
if (page->isShared()) {
LockHolder locker(*m_lock);
static_cast<IsoSharedPage*>(page)->free<Config>(locker, handle, ptr);
return;
}
if (m_objectLog.size() == m_objectLog.capacity())
scavenge();
m_objectLog.push(ptr);
}
template<typename Config>
BNO_INLINE void IsoDeallocator<Config>::scavenge()
{
LockHolder locker(*m_lock);
for (void* ptr : m_objectLog)
IsoPage<Config>::pageFor(ptr)->free(locker, ptr);
m_objectLog.clear();
}
} // namespace bmalloc