whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 1 | // Copyright 2010 the V8 project authors. All rights reserved. |
| 2 | // Redistribution and use in source and binary forms, with or without |
| 3 | // modification, are permitted provided that the following conditions are |
| 4 | // met: |
| 5 | // |
| 6 | // * Redistributions of source code must retain the above copyright |
| 7 | // notice, this list of conditions and the following disclaimer. |
| 8 | // * Redistributions in binary form must reproduce the above |
| 9 | // copyright notice, this list of conditions and the following |
| 10 | // disclaimer in the documentation and/or other materials provided |
| 11 | // with the distribution. |
| 12 | // * Neither the name of Google Inc. nor the names of its |
| 13 | // contributors may be used to endorse or promote products derived |
| 14 | // from this software without specific prior written permission. |
| 15 | // |
| 16 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 17 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 18 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 19 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 20 | // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 21 | // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 22 | // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 23 | // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 24 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 25 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 26 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | |
| 28 | #include "v8.h" |
| 29 | |
| 30 | #include "circular-queue-inl.h" |
| 31 | |
| 32 | namespace v8 { |
| 33 | namespace internal { |
| 34 | |
| 35 | |
| 36 | SamplingCircularQueue::SamplingCircularQueue(int record_size_in_bytes, |
| 37 | int desired_chunk_size_in_bytes, |
| 38 | int buffer_size_in_chunks) |
| 39 | : record_size_(record_size_in_bytes / sizeof(Cell)), |
| 40 | chunk_size_in_bytes_(desired_chunk_size_in_bytes / record_size_in_bytes * |
| 41 | record_size_in_bytes), |
| 42 | chunk_size_(chunk_size_in_bytes_ / sizeof(Cell)), |
| 43 | buffer_size_(chunk_size_ * buffer_size_in_chunks), |
| 44 | // The distance ensures that producer and consumer never step on |
| 45 | // each other's chunks and helps eviction of produced data from |
| 46 | // the CPU cache (having that chunk size is bigger than the cache.) |
| 47 | producer_consumer_distance_(2 * chunk_size_), |
| 48 | buffer_(NewArray<Cell>(buffer_size_ + 1)) { |
| 49 | ASSERT(buffer_size_in_chunks > 2); |
| 50 | // Only need to keep the first cell of a chunk clean. |
| 51 | for (int i = 0; i < buffer_size_; i += chunk_size_) { |
| 52 | buffer_[i] = kClear; |
| 53 | } |
| 54 | buffer_[buffer_size_] = kEnd; |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 55 | |
| 56 | // Layout producer and consumer position pointers each on their own |
| 57 | // cache lines to avoid cache lines thrashing due to simultaneous |
| 58 | // updates of positions by different processor cores. |
| 59 | const int positions_size = |
| 60 | RoundUp(1, kProcessorCacheLineSize) + |
whesse@chromium.org | b6e43bb | 2010-04-14 09:36:28 +0000 | [diff] [blame^] | 61 | RoundUp(static_cast<int>(sizeof(ProducerPosition)), |
| 62 | kProcessorCacheLineSize) + |
| 63 | RoundUp(static_cast<int>(sizeof(ConsumerPosition)), |
| 64 | kProcessorCacheLineSize); |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 65 | positions_ = NewArray<byte>(positions_size); |
| 66 | |
| 67 | producer_pos_ = reinterpret_cast<ProducerPosition*>( |
| 68 | RoundUp(positions_, kProcessorCacheLineSize)); |
| 69 | producer_pos_->enqueue_pos = buffer_; |
| 70 | |
| 71 | consumer_pos_ = reinterpret_cast<ConsumerPosition*>( |
| 72 | reinterpret_cast<byte*>(producer_pos_) + kProcessorCacheLineSize); |
| 73 | ASSERT(reinterpret_cast<byte*>(consumer_pos_ + 1) <= |
| 74 | positions_ + positions_size); |
| 75 | consumer_pos_->dequeue_chunk_pos = buffer_; |
| 76 | consumer_pos_->dequeue_chunk_poll_pos = buffer_ + producer_consumer_distance_; |
| 77 | consumer_pos_->dequeue_pos = NULL; |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 78 | } |
| 79 | |
| 80 | |
| 81 | SamplingCircularQueue::~SamplingCircularQueue() { |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 82 | DeleteArray(positions_); |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 83 | DeleteArray(buffer_); |
| 84 | } |
| 85 | |
| 86 | |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 87 | void* SamplingCircularQueue::StartDequeue() { |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 88 | if (consumer_pos_->dequeue_pos != NULL) { |
| 89 | return consumer_pos_->dequeue_pos; |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 90 | } else { |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 91 | if (*consumer_pos_->dequeue_chunk_poll_pos != kClear) { |
| 92 | consumer_pos_->dequeue_pos = consumer_pos_->dequeue_chunk_pos; |
| 93 | consumer_pos_->dequeue_end_pos = consumer_pos_->dequeue_pos + chunk_size_; |
| 94 | return consumer_pos_->dequeue_pos; |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 95 | } else { |
| 96 | return NULL; |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | |
| 102 | void SamplingCircularQueue::FinishDequeue() { |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 103 | consumer_pos_->dequeue_pos += record_size_; |
| 104 | if (consumer_pos_->dequeue_pos < consumer_pos_->dequeue_end_pos) return; |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 105 | // Move to next chunk. |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 106 | consumer_pos_->dequeue_pos = NULL; |
| 107 | *consumer_pos_->dequeue_chunk_pos = kClear; |
| 108 | consumer_pos_->dequeue_chunk_pos += chunk_size_; |
| 109 | WrapPositionIfNeeded(&consumer_pos_->dequeue_chunk_pos); |
| 110 | consumer_pos_->dequeue_chunk_poll_pos += chunk_size_; |
| 111 | WrapPositionIfNeeded(&consumer_pos_->dequeue_chunk_poll_pos); |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 112 | } |
| 113 | |
| 114 | |
| 115 | void SamplingCircularQueue::FlushResidualRecords() { |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 116 | // Eliminate producer / consumer distance. |
kmillikin@chromium.org | 5d8f0e6 | 2010-03-24 08:21:20 +0000 | [diff] [blame] | 117 | consumer_pos_->dequeue_chunk_poll_pos = consumer_pos_->dequeue_chunk_pos; |
whesse@chromium.org | cec079d | 2010-03-22 14:44:04 +0000 | [diff] [blame] | 118 | } |
| 119 | |
| 120 | |
| 121 | } } // namespace v8::internal |