Function borrow_keytable

src/bthread/key.cpp:329–370

};

KeyTable* borrow_keytable(bthread_keytable_pool_t* pool) {
    if (pool != NULL && (pool->list || pool->free_keytables)) {
        KeyTable* p;
        pthread_rwlock_rdlock(&pool->rwlock);
        auto list = (butil::ThreadLocal<bthread::KeyTableList>*)pool->list;
        if (list) {
            p = list->get()->remove_front();
            if (p) {
                pthread_rwlock_unlock(&pool->rwlock);
                return p;
            }
        }
        pthread_rwlock_unlock(&pool->rwlock);
        if (pool->free_keytables) {
            pthread_rwlock_wrlock(&pool->rwlock);
            p = (KeyTable*)pool->free_keytables;
            if (list) {
                for (uint32_t i = 0; i < FLAGS_borrow_from_globle_size; ++i) {
                    if (p) {
                        pool->free_keytables = p->next;
                        list->get()->append(p);
                        p = (KeyTable*)pool->free_keytables;
                        --pool->size;
                    } else {
                        break;
                    }
                }
                KeyTable* result = list->get()->remove_front();
                pthread_rwlock_unlock(&pool->rwlock);
                return result;
            } else {
                if (p) {
                    pool->free_keytables = p->next;
                    pthread_rwlock_unlock(&pool->rwlock);
                    return p;
                }
            }
            pthread_rwlock_unlock(&pool->rwlock);
        }
    }
    return NULL;
}

// Referenced in task_group.cpp, must be extern.
// Caller of this function must hold the KeyTable