1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/ipc/glue/SharedMemory.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,99 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set ts=8 sts=2 et sw=2 tw=80: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#include <math.h>
1.11 +
1.12 +#include "nsString.h"
1.13 +#include "nsIMemoryReporter.h"
1.14 +#include "mozilla/ipc/SharedMemory.h"
1.15 +#include "mozilla/Atomics.h"
1.16 +
1.17 +namespace mozilla {
1.18 +namespace ipc {
1.19 +
1.20 +static Atomic<size_t> gShmemAllocated;
1.21 +static Atomic<size_t> gShmemMapped;
1.22 +
1.23 +class ShmemReporter MOZ_FINAL : public nsIMemoryReporter
1.24 +{
1.25 +public:
1.26 + NS_DECL_THREADSAFE_ISUPPORTS
1.27 +
1.28 + NS_IMETHOD
1.29 + CollectReports(nsIHandleReportCallback* aHandleReport, nsISupports* aData)
1.30 + {
1.31 + nsresult rv;
1.32 + rv = MOZ_COLLECT_REPORT(
1.33 + "shmem-allocated", KIND_OTHER, UNITS_BYTES, gShmemAllocated,
1.34 + "Memory shared with other processes that is accessible (but not "
1.35 + "necessarily mapped).");
1.36 + NS_ENSURE_SUCCESS(rv, rv);
1.37 +
1.38 + rv = MOZ_COLLECT_REPORT(
1.39 + "shmem-mapped", KIND_OTHER, UNITS_BYTES, gShmemMapped,
1.40 + "Memory shared with other processes that is mapped into the address "
1.41 + "space.");
1.42 + NS_ENSURE_SUCCESS(rv, rv);
1.43 +
1.44 + return NS_OK;
1.45 + }
1.46 +};
1.47 +
1.48 +NS_IMPL_ISUPPORTS(ShmemReporter, nsIMemoryReporter)
1.49 +
1.50 +SharedMemory::SharedMemory()
1.51 + : mAllocSize(0)
1.52 + , mMappedSize(0)
1.53 +{
1.54 + MOZ_COUNT_CTOR(SharedMemory);
1.55 + static Atomic<bool> registered;
1.56 + if (registered.compareExchange(false, true)) {
1.57 + RegisterStrongMemoryReporter(new ShmemReporter());
1.58 + }
1.59 +}
1.60 +
1.61 +/*static*/ size_t
1.62 +SharedMemory::PageAlignedSize(size_t aSize)
1.63 +{
1.64 + size_t pageSize = SystemPageSize();
1.65 + size_t nPagesNeeded = size_t(ceil(double(aSize) / double(pageSize)));
1.66 + return pageSize * nPagesNeeded;
1.67 +}
1.68 +
1.69 +void
1.70 +SharedMemory::Created(size_t aNBytes)
1.71 +{
1.72 + mAllocSize = aNBytes;
1.73 + gShmemAllocated += mAllocSize;
1.74 +}
1.75 +
1.76 +void
1.77 +SharedMemory::Mapped(size_t aNBytes)
1.78 +{
1.79 + mMappedSize = aNBytes;
1.80 + gShmemMapped += mMappedSize;
1.81 +}
1.82 +
1.83 +void
1.84 +SharedMemory::Unmapped()
1.85 +{
1.86 + NS_ABORT_IF_FALSE(gShmemMapped >= mMappedSize,
1.87 + "Can't unmap more than mapped");
1.88 + gShmemMapped -= mMappedSize;
1.89 + mMappedSize = 0;
1.90 +}
1.91 +
1.92 +/*static*/ void
1.93 +SharedMemory::Destroyed()
1.94 +{
1.95 + NS_ABORT_IF_FALSE(gShmemAllocated >= mAllocSize,
1.96 + "Can't destroy more than allocated");
1.97 + gShmemAllocated -= mAllocSize;
1.98 + mAllocSize = 0;
1.99 +}
1.100 +
1.101 +} // namespace ipc
1.102 +} // namespace mozilla
