From 88b942cf07bce15956c20bbba3d3e4edd0a24d8c Mon Sep 17 00:00:00 2001
From: itrofimow <itrofimow@userver.tech>
Date: Thu, 16 Nov 2023 04:25:44 +0300
Subject: [PATCH] feat all: drop phdr-cache experiment, enable it by default

---
 core/include/userver/utils/impl/userver_experiments.hpp | 2 --
 core/src/engine/task/exception_hacks.cpp                | 6 +++---
 core/src/utils/impl/userver_experiments.cpp             | 2 --
 core/testing/src/utest/gtest_hooks.cpp                  | 9 +--------
 4 files changed, 4 insertions(+), 15 deletions(-)

diff --git a/core/include/userver/utils/impl/userver_experiments.hpp b/core/include/userver/utils/impl/userver_experiments.hpp
index ddcf66341e54..c448e49e0983 100644
--- a/core/include/userver/utils/impl/userver_experiments.hpp
+++ b/core/include/userver/utils/impl/userver_experiments.hpp
@@ -62,8 +62,6 @@ class UserverExperimentsScope final {
 // TODO move to userver/mongo once the issues with linker are resolved.
 extern UserverExperiment kRedisClusterAutoTopologyExperiment;
 
-extern UserverExperiment kPhdrCacheExperiment;
-
 }  // namespace utils::impl
 
 USERVER_NAMESPACE_END
diff --git a/core/src/engine/task/exception_hacks.cpp b/core/src/engine/task/exception_hacks.cpp
index ae26cf51573d..afed70b5030e 100644
--- a/core/src/engine/task/exception_hacks.cpp
+++ b/core/src/engine/task/exception_hacks.cpp
@@ -151,11 +151,12 @@ std::atomic<PhdrCacheStorage*> phdr_cache_ptr{nullptr};
 class PhdrCache final {
  public:
   void Initialize() {
-    if (!utils::impl::kPhdrCacheExperiment.IsEnabled()) {
+    if (phdr_cache_ptr.load() != nullptr) {
       return;
     }
     LOG_INFO() << "Initializing phdr cache";
 
+    cache_.clear();
     GetOriginalDlIteratePhdr()(
         [](dl_phdr_info* info, size_t /* size */, void* data) {
           reinterpret_cast<PhdrCacheStorage*>(data)->push_back(*info);
@@ -163,8 +164,7 @@ class PhdrCache final {
         },
         &cache_);
 
-    [[maybe_unused]] const auto* old_cache = phdr_cache_ptr.exchange(&cache_);
-    UASSERT(!old_cache);
+    phdr_cache_ptr.exchange(&cache_);
 
     LOG_INFO() << "Initialized phdr cache for " << cache_.size() << " objects";
   }
diff --git a/core/src/utils/impl/userver_experiments.cpp b/core/src/utils/impl/userver_experiments.cpp
index 0f22ee9527fa..fb75b4e55a4c 100644
--- a/core/src/utils/impl/userver_experiments.cpp
+++ b/core/src/utils/impl/userver_experiments.cpp
@@ -99,8 +99,6 @@ void UserverExperimentsScope::EnableOnly(
 UserverExperiment kRedisClusterAutoTopologyExperiment{
     "redis-cluster-autotopology"};
 
-UserverExperiment kPhdrCacheExperiment{"phdr-cache"};
-
 }  // namespace utils::impl
 
 USERVER_NAMESPACE_END
diff --git a/core/testing/src/utest/gtest_hooks.cpp b/core/testing/src/utest/gtest_hooks.cpp
index 10596ff36627..ea9c3c3bfe18 100644
--- a/core/testing/src/utest/gtest_hooks.cpp
+++ b/core/testing/src/utest/gtest_hooks.cpp
@@ -45,14 +45,7 @@ void SetLogLevel(logging::Level log_level) {
   logging::SetDefaultLoggerLevel(log_level);
 }
 
-void InitPhdrCache() {
-  static USERVER_NAMESPACE::utils::impl::UserverExperimentsScope
-      phdr_cache_scope{};
-  phdr_cache_scope.Set(USERVER_NAMESPACE::utils::impl::kPhdrCacheExperiment,
-                       true);
-
-  USERVER_NAMESPACE::engine::impl::InitPhdrCache();
-}
+void InitPhdrCache() { USERVER_NAMESPACE::engine::impl::InitPhdrCache(); }
 
 void TeardownPhdrCache() {
   USERVER_NAMESPACE::engine::impl::TeardownPhdrCacheAndEnableDynamicLoading();