DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (c68fe15a81fc)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et ft=cpp : */
/* 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 "mozilla/ShmemPool.h"

#include <utility>

#include "mozilla/Assertions.h"
#include "mozilla/Assertions.h"
#include "mozilla/Logging.h"

mozilla::LazyLogModule sShmemPoolLog("ShmemPool");

#define SHMEMPOOL_LOG_VERBOSE(args) \
  MOZ_LOG(sShmemPoolLog, mozilla::LogLevel::Verbose, args)


namespace mozilla {

ShmemPool::ShmemPool(size_t aPoolSize, PoolType aPoolType)
    : mPoolType(aPoolType),
      mMutex("mozilla::ShmemPool"),
      mMutex("mozilla::ShmemPool"),
      mPoolFree(aPoolSize),
      mErrorLogged(false)
#ifdef DEBUG
      ,
      mMaxPoolUse(0)
      mMaxPoolUse(0)
#endif
{
  mShmemPool.SetLength(aPoolSize);
}

mozilla::ShmemBuffer ShmemPool::GetIfAvailable(size_t aSize) {
mozilla::ShmemBuffer ShmemPool::GetIfAvailable(size_t aSize) {
  MutexAutoLock lock(mMutex);

  // Pool is empty, don't block caller.
  if (mPoolFree == 0) {
    if (!mErrorLogged) {
    if (!mErrorLogged) {
      // log "out of pool" once as error to avoid log spam
      mErrorLogged = true;
      SHMEMPOOL_LOG_ERROR(
          ("ShmemPool is empty, future occurrences "
           "will be logged as warnings"));
           "will be logged as warnings"));
    } else {
      SHMEMPOOL_LOG_WARN(("ShmemPool is empty"));
    }
    // This isn't initialized, so will be understood as an error.
    return ShmemBuffer();
  }

  ShmemBuffer& res = mShmemPool[mPoolFree - 1];


  if (!res.mInitialized) {
    SHMEMPOOL_LOG(("No free preallocated Shmem"));
    return ShmemBuffer();
  }


  MOZ_ASSERT(res.mShmem.IsWritable(), "Pool in Shmem is not writable?");

  if (res.mShmem.Size<uint8_t>() < aSize) {
    SHMEMPOOL_LOG(("Free Shmem but not of the right size"));
    return ShmemBuffer();
    return ShmemBuffer();
  }

  mPoolFree--;
#ifdef DEBUG
  size_t poolUse = mShmemPool.Length() - mPoolFree;
  size_t poolUse = mShmemPool.Length() - mPoolFree;
  if (poolUse > mMaxPoolUse) {
    mMaxPoolUse = poolUse;
    SHMEMPOOL_LOG(
        ("Maximum ShmemPool use increased: %zu buffers", mMaxPoolUse));
  }
#endif
#endif
  return std::move(res);
}

void ShmemPool::Put(ShmemBuffer&& aShmem) {
  MutexAutoLock lock(mMutex);
  MutexAutoLock lock(mMutex);
  MOZ_ASSERT(mPoolFree < mShmemPool.Length());
  mShmemPool[mPoolFree] = std::move(aShmem);
  mPoolFree++;
#ifdef DEBUG
#ifdef DEBUG
  size_t poolUse = mShmemPool.Length() - mPoolFree;
  if (poolUse > 0) {
    SHMEMPOOL_LOG_VERBOSE(("ShmemPool usage reduced to %zu buffers", poolUse));
  }
#endif
#endif
}

ShmemPool::~ShmemPool() {
#ifdef DEBUG
  for (size_t i = 0; i < mShmemPool.Length(); i++) {
  for (size_t i = 0; i < mShmemPool.Length(); i++) {
    MOZ_ASSERT(!mShmemPool[i].Valid());
  }
#endif
}


}  // namespace mozilla