Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(75)

Unified Diff: src/circular-queue.cc

Issue 22849002: Rewrite SamplingCircularQueue (Closed) Base URL: https://v8.googlecode.com/svn/branches/bleeding_edge
Patch Set: Use V8_ALIGNAS from include/v8config.h Created 7 years, 4 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « src/circular-queue.h ('k') | src/circular-queue-inl.h » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: src/circular-queue.cc
diff --git a/src/circular-queue.cc b/src/circular-queue.cc
deleted file mode 100644
index 0aea3435927491511ef72b56147949389250f79d..0000000000000000000000000000000000000000
--- a/src/circular-queue.cc
+++ /dev/null
@@ -1,125 +0,0 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-// * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-// * 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.
-// * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived
-// from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "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 THE COPYRIGHT
-// OWNER 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.
-
-#include "v8.h"
-
-#include "circular-queue-inl.h"
-
-namespace v8 {
-namespace internal {
-
-
-SamplingCircularQueue::SamplingCircularQueue(size_t record_size_in_bytes,
- size_t desired_chunk_size_in_bytes,
- unsigned buffer_size_in_chunks)
- : record_size_(record_size_in_bytes / sizeof(Cell)),
- chunk_size_in_bytes_(desired_chunk_size_in_bytes / record_size_in_bytes *
- record_size_in_bytes + sizeof(Cell)),
- chunk_size_(chunk_size_in_bytes_ / sizeof(Cell)),
- buffer_size_(chunk_size_ * buffer_size_in_chunks),
- buffer_(NewArray<Cell>(buffer_size_)) {
- ASSERT(record_size_ * sizeof(Cell) == record_size_in_bytes);
- ASSERT(chunk_size_ * sizeof(Cell) == chunk_size_in_bytes_);
- ASSERT(buffer_size_in_chunks > 2);
- // Mark all chunks as clear.
- for (size_t i = 0; i < buffer_size_; i += chunk_size_) {
- buffer_[i] = kClear;
- }
-
- // Layout producer and consumer position pointers each on their own
- // cache lines to avoid cache lines thrashing due to simultaneous
- // updates of positions by different processor cores.
- const int positions_size =
- RoundUp(1, kProcessorCacheLineSize) +
- RoundUp(static_cast<int>(sizeof(ProducerPosition)),
- kProcessorCacheLineSize) +
- RoundUp(static_cast<int>(sizeof(ConsumerPosition)),
- kProcessorCacheLineSize);
- positions_ = NewArray<byte>(positions_size);
-
- producer_pos_ = reinterpret_cast<ProducerPosition*>(
- RoundUp(positions_, kProcessorCacheLineSize));
- producer_pos_->next_chunk_pos = buffer_;
- producer_pos_->enqueue_pos = buffer_;
-
- consumer_pos_ = reinterpret_cast<ConsumerPosition*>(
- reinterpret_cast<byte*>(producer_pos_) + kProcessorCacheLineSize);
- ASSERT(reinterpret_cast<byte*>(consumer_pos_ + 1) <=
- positions_ + positions_size);
- consumer_pos_->dequeue_chunk_pos = buffer_;
- // The distance ensures that producer and consumer never step on
- // each other's chunks and helps eviction of produced data from
- // the CPU cache (having that chunk size is bigger than the cache.)
- const size_t producer_consumer_distance = (2 * chunk_size_);
- consumer_pos_->dequeue_chunk_poll_pos = buffer_ + producer_consumer_distance;
- consumer_pos_->dequeue_pos = NULL;
-}
-
-
-SamplingCircularQueue::~SamplingCircularQueue() {
- DeleteArray(positions_);
- DeleteArray(buffer_);
-}
-
-
-void* SamplingCircularQueue::StartDequeue() {
- if (consumer_pos_->dequeue_pos != NULL) {
- return consumer_pos_->dequeue_pos;
- } else {
- if (Acquire_Load(consumer_pos_->dequeue_chunk_poll_pos) != kClear) {
- // Skip marker.
- consumer_pos_->dequeue_pos = consumer_pos_->dequeue_chunk_pos + 1;
- consumer_pos_->dequeue_end_pos =
- consumer_pos_->dequeue_chunk_pos + chunk_size_;
- return consumer_pos_->dequeue_pos;
- } else {
- return NULL;
- }
- }
-}
-
-
-void SamplingCircularQueue::FinishDequeue() {
- consumer_pos_->dequeue_pos += record_size_;
- if (consumer_pos_->dequeue_pos < consumer_pos_->dequeue_end_pos) return;
- // Move to next chunk.
- consumer_pos_->dequeue_pos = NULL;
- *consumer_pos_->dequeue_chunk_pos = kClear;
- consumer_pos_->dequeue_chunk_pos += chunk_size_;
- WrapPositionIfNeeded(&consumer_pos_->dequeue_chunk_pos);
- consumer_pos_->dequeue_chunk_poll_pos += chunk_size_;
- WrapPositionIfNeeded(&consumer_pos_->dequeue_chunk_poll_pos);
-}
-
-
-void SamplingCircularQueue::FlushResidualRecords() {
- // Eliminate producer / consumer distance.
- consumer_pos_->dequeue_chunk_poll_pos = consumer_pos_->dequeue_chunk_pos;
-}
-
-
-} } // namespace v8::internal
« no previous file with comments | « src/circular-queue.h ('k') | src/circular-queue-inl.h » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698