more refactoring

Author: bajajneha27

google/cloud/storage/internal/bucket_metadata_cache.cc

@@ -21,27 +21,27 @@ namespace cloud {
 namespace storage_internal {
 GOOGLE_CLOUD_CPP_INLINE_NAMESPACE_BEGIN
 
+void BucketMetadataCache::MoveToFront(std::list<std::string>::iterator it) {
+  list_.splice(list_.begin(), list_, it);
+}
+
 absl::optional<BucketCacheEntry> BucketMetadataCache::Get(
     std::string const& bucket_name) {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   auto it = map_.find(bucket_name);
   if (it == map_.end()) return absl::nullopt;
 
-  list_.erase(it->second.second);
-  list_.push_front(bucket_name);
-  it->second.second = list_.begin();
+  MoveToFront(it->second.second);
   return it->second.first;
 }
 
 void BucketMetadataCache::Put(std::string const& bucket_name,
                               BucketCacheEntry entry) {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   auto it = map_.find(bucket_name);
   if (it != map_.end()) {
     it->second.first = std::move(entry);
-    list_.erase(it->second.second);
-    list_.push_front(bucket_name);
-    it->second.second = list_.begin();
+    MoveToFront(it->second.second);
     return;
   }
 
@@ -56,7 +56,7 @@ void BucketMetadataCache::Put(std::string const& bucket_name,
 }
 
 void BucketMetadataCache::Invalidate(std::string const& bucket_name) {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   auto it = map_.find(bucket_name);
   if (it != map_.end()) {
     list_.erase(it->second.second);
@@ -65,14 +65,14 @@ void BucketMetadataCache::Invalidate(std::string const& bucket_name) {
 }
 
 void BucketMetadataCache::Clear() {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   map_.clear();
   list_.clear();
   in_flight_fetch_.clear();
 }
 
 bool BucketMetadataCache::StartFetch(std::string const& bucket_name) {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   if (in_flight_fetch_.find(bucket_name) != in_flight_fetch_.end()) {
     return false;
   }
@@ -81,7 +81,7 @@ bool BucketMetadataCache::StartFetch(std::string const& bucket_name) {
 }
 
 void BucketMetadataCache::EndFetch(std::string const& bucket_name) {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   in_flight_fetch_.erase(bucket_name);
 }
 

google/cloud/storage/internal/bucket_metadata_cache.h

@@ -48,6 +48,8 @@ class BucketMetadataCache {
   void EndFetch(std::string const& bucket_name);
 
  private:
+  void MoveToFront(std::list<std::string>::iterator it);
+
   std::size_t max_size_;
   std::mutex mu_;
   std::list<std::string> list_;

google/cloud/storage/internal/tracing_connection.cc

@@ -18,7 +18,6 @@
 #include "google/cloud/internal/opentelemetry.h"
 #include "google/cloud/options.h"
 #include <algorithm>
-#include <iostream>
 #include <memory>
 #include <string>
 #include <utility>
@@ -48,7 +47,7 @@ void TracingConnection::ResetCacheForTesting() { cache().Clear(); }
 Options TracingConnection::options() const { return impl_->options(); }
 
 void TracingConnection::CleanupCompletedTasks() {
-  std::lock_guard<std::mutex> lock(mu_);
+  std::unique_lock<std::mutex> lk(mu_);
   bg_tasks_.erase(std::remove_if(bg_tasks_.begin(), bg_tasks_.end(),
                                  [](std::future<void> const& f) {
                                    return f.wait_for(std::chrono::seconds(0)) ==
@@ -71,14 +70,6 @@ void TracingConnection::MaybeTriggerBackgroundFetch(
         google::cloud::internal::OptionsSpan span(current_options);
         storage::internal::GetBucketMetadataRequest request(bucket_name);
         auto result = impl_->GetBucketMetadata(request);
-        std::cout << "BG Thread: GetBucketMetadata returned ok: " << result.ok()
-                  << "\n";
-        if (!result.ok()) {
-          std::cout << "BG Thread: GetBucketMetadata status: "
-                    << result.status().message()
-                    << " code: " << static_cast<int>(result.status().code())
-                    << "\n";
-        }
 
         BucketCacheEntry entry;
         if (result.ok()) {