From a78ebc27de56c80826f4ae27f8954dba65671b47 Mon Sep 17 00:00:00 2001
From: Coldwings <coldwings@me.com>
Date: Wed, 10 Jul 2024 16:47:11 +0800
Subject: [PATCH] Use atomic sharedptr operation (for C++11~20) instead of
 reflock

---
 common/objectcachev2.h        | 12 ++++++------
 common/test/perf_objcache.cpp |  4 ++--
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/common/objectcachev2.h b/common/objectcachev2.h
index 4fdcfcce..20e7422a 100644
--- a/common/objectcachev2.h
+++ b/common/objectcachev2.h
@@ -37,7 +37,6 @@ class ObjectCacheV2 {
         const K key;
         std::shared_ptr<V> ref;
         photon::spinlock boxlock;
-        photon::spinlock reflock;
         uint64_t lastcreate = 0;
         uint64_t timestamp = 0;
 
@@ -50,11 +49,12 @@ class ObjectCacheV2 {
             // other reader will get new one after updated
             std::shared_ptr<V> update(V* val, uint64_t ts = 0,
                                       std::shared_ptr<V>* newptr = nullptr) {
-                SCOPED_LOCK(box->reflock);
                 auto r = std::shared_ptr<V>(val);
-                if (newptr) *newptr = r;
+                if (newptr)
+                    std::atomic_store(newptr, r);
+                *newptr = r;
                 box->lastcreate = ts;
-                std::swap(r, box->ref);
+                r = std::atomic_exchange(&box->ref, r);
                 return r;
             }
 
@@ -79,8 +79,7 @@ class ObjectCacheV2 {
 
         Updater writer() { return Updater(this); }
         std::shared_ptr<V> reader() {
-            SCOPED_LOCK(reflock);
-            return ref;
+            return std::atomic_load(&ref);
         }
     };
     struct ItemHash {
@@ -173,6 +172,7 @@ class ObjectCacheV2 {
         Borrow& operator=(Borrow&& rhs) {
             std::swap(_oc, rhs._oc);
             std::swap(_item, rhs._item);
+            _reader = std::atomic_exchange(&rhs._reader, _reader);
             std::swap(_reader, rhs._reader);
             std::swap(_recycle, rhs._recycle);
             return *this;
diff --git a/common/test/perf_objcache.cpp b/common/test/perf_objcache.cpp
index 257af4f1..71a7e558 100644
--- a/common/test/perf_objcache.cpp
+++ b/common/test/perf_objcache.cpp
@@ -40,7 +40,7 @@ void *task(void *arg) {
     for (const auto &x : k) {
         auto strx = std::to_string(x);
         auto b = oc->borrow(strx, [&strx] {
-            photon::thread_usleep(1 * 1000);
+            // photon::thread_usleep(1 * 1000);
             // LOG_INFO("CTOR `", photon::now);
             return new std::string(strx);
         });
@@ -64,7 +64,7 @@ void test_objcache(OC<std::string, std::string *> &oc, const char *name) {
 
 template <template <class, class> class OC>
 void test(const char *name) {
-    OC<std::string, std::string *> oc(-1UL);
+    OC<std::string, std::string *> oc(0);
     std::vector<std::thread> ths;
     photon::semaphore sem(0);
     for (int i = 0; i < 10; i++) {