1 files changed, 76 insertions, 0 deletions
diff --git a/src/rocksdb/util/dynamic_bloom.cc b/src/rocksdb/util/dynamic_bloom.cc
new file mode 100644
index 00000000..8e90efd8
--- /dev/null
+++ b/src/rocksdb/util/dynamic_bloom.cc
@@ -0,0 +1,76 @@
+// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#include "dynamic_bloom.h"
+
+#include <algorithm>
+
+#include "port/port.h"
+#include "rocksdb/slice.h"
+#include "util/allocator.h"
+#include "util/hash.h"
+
+namespace rocksdb {
+
+namespace {
+
+uint32_t GetTotalBitsForLocality(uint32_t total_bits) {
+  uint32_t num_blocks =
+      (total_bits + CACHE_LINE_SIZE * 8 - 1) / (CACHE_LINE_SIZE * 8);
+
+  // Make num_blocks an odd number to make sure more bits are involved
+  // when determining which block.
+  if (num_blocks % 2 == 0) {
+    num_blocks++;
+  }
+
+  return num_blocks * (CACHE_LINE_SIZE * 8);
+}
+}
+
+DynamicBloom::DynamicBloom(Allocator* allocator, uint32_t total_bits,
+                           uint32_t locality, uint32_t num_probes,
+                           size_t huge_page_tlb_size, Logger* logger)
+    : DynamicBloom(num_probes) {
+  SetTotalBits(allocator, total_bits, locality, huge_page_tlb_size, logger);
+}
+
+DynamicBloom::DynamicBloom(uint32_t num_probes)
+    : kTotalBits(0), kNumBlocks(0), kNumProbes(num_probes), data_(nullptr) {}
+
+void DynamicBloom::SetRawData(unsigned char* raw_data, uint32_t total_bits,
+                              uint32_t num_blocks) {
+  data_ = reinterpret_cast<std::atomic<uint8_t>*>(raw_data);
+  kTotalBits = total_bits;
+  kNumBlocks = num_blocks;
+}
+
+void DynamicBloom::SetTotalBits(Allocator* allocator,
+                                uint32_t total_bits, uint32_t locality,
+                                size_t huge_page_tlb_size,
+                                Logger* logger) {
+  kTotalBits = (locality > 0) ? GetTotalBitsForLocality(total_bits)
+                              : (total_bits + 7) / 8 * 8;
+  kNumBlocks = (locality > 0) ? (kTotalBits / (CACHE_LINE_SIZE * 8)) : 0;
+
+  assert(kNumBlocks > 0 || kTotalBits > 0);
+  assert(kNumProbes > 0);
+
+  uint32_t sz = kTotalBits / 8;
+  if (kNumBlocks > 0) {
+    sz += CACHE_LINE_SIZE - 1;
+  }
+  assert(allocator);
+
+  char* raw = allocator->AllocateAligned(sz, huge_page_tlb_size, logger);
+  memset(raw, 0, sz);
+  auto cache_line_offset = reinterpret_cast<uintptr_t>(raw) % CACHE_LINE_SIZE;
+  if (kNumBlocks > 0 && cache_line_offset > 0) {
+    raw += CACHE_LINE_SIZE - cache_line_offset;
+  }
+  data_ = reinterpret_cast<std::atomic<uint8_t>*>(raw);
+}
+
+}  // rocksdb