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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include <math.h>
#include "nsString.h"
#include "nsIMemoryReporter.h"
#include "mozilla/ipc/SharedMemory.h"
#include "mozilla/Atomics.h"
namespace mozilla {
namespace ipc {
static Atomic<size_t> gShmemAllocated;
static Atomic<size_t> gShmemMapped;
class ShmemReporter final : public nsIMemoryReporter {
~ShmemReporter() = default;
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_IMETHOD
CollectReports(nsIHandleReportCallback* aHandleReport, nsISupports* aData,
bool aAnonymize) override {
MOZ_COLLECT_REPORT(
"shmem-allocated", KIND_OTHER, UNITS_BYTES, gShmemAllocated,
"Memory shared with other processes that is accessible (but not "
"necessarily mapped).");
MOZ_COLLECT_REPORT(
"shmem-mapped", KIND_OTHER, UNITS_BYTES, gShmemMapped,
"Memory shared with other processes that is mapped into the address "
"space.");
return NS_OK;
}
};
NS_IMPL_ISUPPORTS(ShmemReporter, nsIMemoryReporter)
SharedMemory::SharedMemory() : mAllocSize(0), mMappedSize(0) {
static Atomic<bool> registered;
if (registered.compareExchange(false, true)) {
RegisterStrongMemoryReporter(new ShmemReporter());
}
}
/*static*/
size_t SharedMemory::PageAlignedSize(size_t aSize) {
size_t pageSize = SystemPageSize();
size_t nPagesNeeded = size_t(ceil(double(aSize) / double(pageSize)));
return pageSize * nPagesNeeded;
}
void SharedMemory::Created(size_t aNBytes) {
mAllocSize = aNBytes;
gShmemAllocated += mAllocSize;
}
void SharedMemory::Mapped(size_t aNBytes) {
mMappedSize = aNBytes;
gShmemMapped += mMappedSize;
}
void SharedMemory::Unmapped() {
MOZ_ASSERT(gShmemMapped >= mMappedSize, "Can't unmap more than mapped");
gShmemMapped -= mMappedSize;
mMappedSize = 0;
}
/*static*/
void SharedMemory::Destroyed() {
MOZ_ASSERT(gShmemAllocated >= mAllocSize,
"Can't destroy more than allocated");
gShmemAllocated -= mAllocSize;
mAllocSize = 0;
}
} // namespace ipc
} // namespace mozilla