common: Implement bthread rwlock try rdlock

Signed-off-by: Hanqing Wu <wuhanqing@corp.netease.com>

WORKSPACE

@@ -143,6 +143,7 @@ git_repository(
         "//:thirdparties/brpc/brpc.patch",
         "//:thirdparties/brpc/fix-gcc11.patch",
         "//:thirdparties/brpc/0001-bvar-warning-on-conflict-bvar-name.patch",
+        "//:thirdparties/brpc/0002-Add-bthread-rwlock-try-rdlock.patch",
     ],
     patch_args = ["-p1"],
 )

curvefs/src/metaserver/mds/fsinfo_manager.cpp

@@ -25,7 +25,7 @@
 namespace curvefs {
 namespace metaserver {
 bool FsInfoManager::GetFsInfo(uint32_t fsId, FsInfo *fsInfo) {
-    std::lock_guard<std::mutex> lock(mtx_);
+    std::lock_guard<bthread::Mutex> lock(mtx_);
     auto iter = fsInfoMap_.find(fsId);
     if (iter == fsInfoMap_.end()) {
         auto ret = mdsClient_->GetFsInfo(fsId, fsInfo);

curvefs/src/metaserver/mds/fsinfo_manager.h

@@ -26,6 +26,8 @@
 #include <map>
 #include <memory>
 #include <mutex>
+
+#include "bthread/mutex.h"
 #include "curvefs/src/client/rpcclient/mds_client.h"
 
 namespace curvefs {
@@ -50,7 +52,7 @@ class FsInfoManager {
     std::shared_ptr<MdsClient> mdsClient_;
     std::map<uint32_t, FsInfo> fsInfoMap_;
 
-    std::mutex mtx_;
+    bthread::Mutex mtx_;
 };
 }  // namespace metaserver
 }  // namespace curvefs

curvefs/src/metaserver/metastore.h

@@ -352,7 +352,7 @@ class MetaStoreImpl : public MetaStore {
     bool ClearInternal();
 
  private:
-    RWLock rwLock_;  // protect partitionMap_
+    curve::common::BthreadRWLock rwLock_;  // protect partitionMap_
     std::shared_ptr<KVStorage> kvStorage_;
     std::map<uint32_t, std::shared_ptr<Partition>> partitionMap_;
     std::list<uint32_t> partitionIds_;

src/common/concurrent/rw_lock.h

@@ -180,8 +180,7 @@ class BthreadRWLock : public RWLockBase {
     }
 
     int TryRDLock() override {
-        LOG(WARNING) << "TryRDLock not support yet";
-        return EINVAL;
+        return bthread_rwlock_tryrdlock(&rwlock_);
     }
 
     void Unlock() override {

thirdparties/brpc/0002-Add-bthread-rwlock-try-rdlock.patch

@@ -0,0 +1,84 @@
+From 044f2fce36404727110cd5fd5bab563d76fba71a Mon Sep 17 00:00:00 2001
+From: Hanqing Wu <wuhanqing@corp.netease.com>
+Date: Mon, 11 Dec 2023 18:12:24 +0800
+Subject: [PATCH] Add bthread rwlock try rdlock
+
+---
+ src/bthread/rwlock.cpp                | 28 +++++++++++++++++++++++++++
+ test/bthread_brpc_rwlock_unittest.cpp | 18 +++++++++++++++++
+ 2 files changed, 46 insertions(+)
+
+diff --git a/src/bthread/rwlock.cpp b/src/bthread/rwlock.cpp
+index 418f4ad0..ca0d49b0 100644
+--- a/src/bthread/rwlock.cpp
++++ b/src/bthread/rwlock.cpp
+@@ -106,6 +106,29 @@ inline int rwlock_rlock(bthread_rwlock_t* rwlock) {
+
+ }
+
++inline int rwlock_tryrdlock(bthread_rwlock_t* rwlock) {
++    butil::atomic<unsigned>* whole =
++        (butil::atomic<unsigned>*)rwlock->lock_flag;
++    butil::atomic<unsigned>* w_wait_count =
++        (butil::atomic<unsigned>*)rwlock->w_wait_count;
++
++    while (1) {
++        unsigned w = w_wait_count->load();
++        if (w > 0) {
++            return EBUSY;
++        }
++        // FIXME!! we don't consider read_wait_count overflow yet,2^31 should be enough here
++        unsigned r = whole->load();
++        if ((r >> 31) == 0) {
++            if (whole->compare_exchange_weak(r, r + 1)) {
++                return 0;
++            }
++        } else {
++            return EBUSY;
++        }
++    }
++}
++
+ inline int rwlock_wlock(bthread_rwlock_t* rwlock) {
+     butil::atomic<unsigned>* w_wait_count = (butil::atomic<unsigned>*)rwlock->w_wait_count;
+     butil::atomic<unsigned>* whole = (butil::atomic<unsigned>*)rwlock->lock_flag;
+@@ -160,4 +183,9 @@ int bthread_rwlock_unrlock(bthread_rwlock_t* rwlock) { return bthread::rwlock_un
+ int bthread_rwlock_unwlock(bthread_rwlock_t* rwlock) { return bthread::rwlock_unwlock(rwlock); }
+
+ int bthread_rwlock_unlock(bthread_rwlock_t* rwlock) { return bthread::rwlock_unlock(rwlock); }
++
++int bthread_rwlock_tryrdlock(bthread_rwlock_t* rwlock) {
++    return bthread::rwlock_tryrdlock(rwlock);
++}
++
+ }
+diff --git a/test/bthread_brpc_rwlock_unittest.cpp b/test/bthread_brpc_rwlock_unittest.cpp
+index f5ce3fb0..345eb322 100644
+--- a/test/bthread_brpc_rwlock_unittest.cpp
++++ b/test/bthread_brpc_rwlock_unittest.cpp
+@@ -195,4 +195,22 @@ TEST(RwlockTest, mix_thread_types) {
+         pthread_join(pthreads[i], NULL);
+     }
+ }
++
++TEST(RWLockTest, try_rdlock_test) {
++    bthread_rwlock_t rwlock;
++    bthread_rwlock_init(&rwlock, NULL);
++
++    ASSERT_EQ(0, bthread_rwlock_rdlock(&rwlock));
++    ASSERT_EQ(0, bthread_rwlock_tryrdlock(&rwlock));
++    ASSERT_EQ(0, bthread_rwlock_unlock(&rwlock));
++    ASSERT_EQ(0, bthread_rwlock_unlock(&rwlock));
++
++    ASSERT_EQ(0, bthread_rwlock_wrlock(&rwlock));
++    ASSERT_EQ(EBUSY, bthread_rwlock_tryrdlock(&rwlock));
++    ASSERT_EQ(0, bthread_rwlock_unlock(&rwlock));
++
++    ASSERT_EQ(0, bthread_rwlock_tryrdlock(&rwlock));
++    ASSERT_EQ(0, bthread_rwlock_unlock(&rwlock));
++}
++
+ } // namespace
+-- 
+2.37.2
+