src/cluster_client.cpp

@@ -193,10 +193,6 @@ void cluster_client_t::inc_wait(uint64_t opcode, uint64_t flags, cluster_op_t *n
                     bh_op_max *= 2;
                     cluster_op_t **n = (cluster_op_t**)malloc_or_die(sizeof(cluster_op_t*) * bh_op_max);
                     memcpy(n, bh_ops, sizeof(cluster_op_t*) * bh_op_count);
-                    if (bh_ops != bh_ops_local)
-                    {
-                        free(bh_ops);
-                    }
                     bh_ops = n;
                 }
                 bh_ops[bh_op_count++] = next;

src/epoll_manager.cpp

@@ -23,24 +23,19 @@ epoll_manager_t::epoll_manager_t(ring_loop_t *ringloop)
 
     tfd = new timerfd_manager_t([this](int fd, bool wr, std::function<void(int, int)> handler) { set_fd_handler(fd, wr, handler); });
 
-    if (ringloop)
-    {
     consumer.loop = [this]()
     {
         if (pending)
-                handle_uring_event();
+            handle_epoll_events();
     };
     ringloop->register_consumer(&consumer);
-        handle_uring_event();
-    }
+
+    handle_epoll_events();
 }
 
 epoll_manager_t::~epoll_manager_t()
-{
-    if (ringloop)
 {
     ringloop->unregister_consumer(&consumer);
-    }
     if (tfd)
     {
         delete tfd;
@@ -49,11 +44,6 @@ epoll_manager_t::~epoll_manager_t()
     close(epoll_fd);
 }
 
-int epoll_manager_t::get_fd()
-{
-    return epoll_fd;
-}
-
 void epoll_manager_t::set_fd_handler(int fd, bool wr, std::function<void(int, int)> handler)
 {
     if (handler != NULL)
@@ -85,7 +75,7 @@ void epoll_manager_t::set_fd_handler(int fd, bool wr, std::function<void(int, in
     }
 }
 
-void epoll_manager_t::handle_uring_event()
+void epoll_manager_t::handle_epoll_events()
 {
     io_uring_sqe *sqe = ringloop->get_sqe();
     if (!sqe)
@@ -105,20 +95,14 @@ void epoll_manager_t::handle_uring_event()
         {
             throw std::runtime_error(std::string("epoll failed: ") + strerror(-data->res));
         }
-        handle_uring_event();
+        handle_epoll_events();
     };
     ringloop->submit();
-    handle_events(0);
-}
-
-void epoll_manager_t::handle_events(int timeout)
-{
     int nfds;
     epoll_event events[MAX_EPOLL_EVENTS];
     do
     {
-        nfds = epoll_wait(epoll_fd, events, MAX_EPOLL_EVENTS, timeout);
-        timeout = 0;
+        nfds = epoll_wait(epoll_fd, events, MAX_EPOLL_EVENTS, 0);
         for (int i = 0; i < nfds; i++)
         {
             auto cb_it = epoll_handlers.find(events[i].data.fd);

src/epoll_manager.h

@@ -15,14 +15,11 @@ class epoll_manager_t
     ring_consumer_t consumer;
     ring_loop_t *ringloop;
     std::map<int, std::function<void(int, int)>> epoll_handlers;
-
-    void handle_uring_event();
 public:
     epoll_manager_t(ring_loop_t *ringloop);
     ~epoll_manager_t();
-    int get_fd();
     void set_fd_handler(int fd, bool wr, std::function<void(int, int)> handler);
-    void handle_events(int timeout);
+    void handle_epoll_events();
 
     timerfd_manager_t *tfd;
 };

src/fio_cluster.cpp

@@ -32,7 +32,6 @@
 struct sec_data
 {
     vitastor_c *cli = NULL;
-    bool epoll_based = false;
     void *watch = NULL;
     bool last_sync = false;
     /* The list of completed io_u structs. */
@@ -59,7 +58,6 @@ struct sec_options
     int rdma_port_num = 0;
     int rdma_gid_index = 0;
     int rdma_mtu = 0;
-    int no_io_uring = 0;
 };
 
 static struct fio_option options[] = {
@@ -195,16 +193,6 @@ static struct fio_option options[] = {
         .category = FIO_OPT_C_ENGINE,
         .group  = FIO_OPT_G_FILENAME,
     },
-    {
-        .name   = "no_io_uring",
-        .lname  = "Disable io_uring",
-        .type   = FIO_OPT_BOOL,
-        .off1   = offsetof(struct sec_options, no_io_uring),
-        .help   = "Use epoll and plain sendmsg/recvmsg instead of io_uring (slower)",
-        .def    = "0",
-        .category = FIO_OPT_C_ENGINE,
-        .group  = FIO_OPT_G_FILENAME,
-    },
     {
         .name = NULL,
     },
@@ -293,17 +281,7 @@ static int sec_setup(struct thread_data *td)
         opt_push(options, "log_level", std::to_string(o->cluster_log).c_str());
     // allow writeback caching if -direct is not set
     opt_push(options, "client_writeback_allowed", td->o.odirect ? "0" : "1");
-    bsd->cli = o->no_io_uring ? NULL : vitastor_c_create_uring_json((const char**)options.data(), options.size());
-    bsd->epoll_based = false;
-    if (!bsd->cli)
-    {
-        if (o->no_io_uring)
-            fprintf(stderr, "vitastor: io_uring disabled - I/O will be slower\n");
-        else
-            fprintf(stderr, "vitastor: failed to create io_uring: %s - I/O will be slower\n", strerror(errno));
-        bsd->cli = vitastor_c_create_epoll_json((const char**)options.data(), options.size());
-        bsd->epoll_based = true;
-    }
+    bsd->cli = vitastor_c_create_uring_json((const char**)options.data(), options.size());
     for (auto opt: options)
         free(opt);
     options.clear();
@@ -311,8 +289,6 @@ static int sec_setup(struct thread_data *td)
     {
         bsd->watch = NULL;
         vitastor_c_watch_inode(bsd->cli, o->image, watch_callback, bsd);
-        if (!bsd->epoll_based)
-        {
         while (true)
         {
             vitastor_c_uring_handle_events(bsd->cli);
@@ -320,16 +296,6 @@ static int sec_setup(struct thread_data *td)
                 break;
             vitastor_c_uring_wait_events(bsd->cli);
         }
-        }
-        else
-        {
-            while (true)
-            {
-                if (bsd->watch)
-                    break;
-                vitastor_c_epoll_handle_events(bsd->cli, 1000);
-            }
-        }
         td->files[0]->real_file_size = vitastor_c_inode_get_size(bsd->watch);
         if (!vitastor_c_inode_get_num(bsd->watch) ||
             !td->files[0]->real_file_size)
@@ -471,8 +437,6 @@ static enum fio_q_status sec_queue(struct thread_data *td, struct io_u *io)
 static int sec_getevents(struct thread_data *td, unsigned int min, unsigned int max, const struct timespec *t)
 {
     sec_data *bsd = (sec_data*)td->io_ops_data;
-    if (!bsd->epoll_based)
-    {
     while (true)
     {
         vitastor_c_uring_handle_events(bsd->cli);
@@ -480,16 +444,6 @@ static int sec_getevents(struct thread_data *td, unsigned int min, unsigned int
             break;
         vitastor_c_uring_wait_events(bsd->cli);
     }
-    }
-    else
-    {
-        while (true)
-        {
-            if (bsd->completed.size() >= min)
-                break;
-            vitastor_c_epoll_handle_events(bsd->cli, 1000);
-        }
-    }
     return bsd->completed.size();
 }
 

src/vitastor_c.cpp

@@ -186,26 +186,12 @@ vitastor_c *vitastor_c_create_uring_json(const char **options, int options_len)
     return self;
 }
 
-vitastor_c *vitastor_c_create_epoll_json(const char **options, int options_len)
-{
-    json11::Json::object cfg;
-    for (int i = 0; i < options_len-1; i += 2)
-    {
-        cfg[options[i]] = std::string(options[i+1]);
-    }
-    json11::Json cfg_json(cfg);
-    vitastor_c *self = new vitastor_c;
-    self->epmgr = new epoll_manager_t(NULL);
-    self->cli = new cluster_client_t(NULL, self->epmgr->tfd, cfg_json);
-    return self;
-}
-
 void vitastor_c_destroy(vitastor_c *client)
 {
     delete client->cli;
     if (client->epmgr)
         delete client->epmgr;
-    else if (client->tfd)
+    else
         delete client->tfd;
     if (client->ringloop)
         delete client->ringloop;
@@ -243,16 +229,6 @@ int vitastor_c_uring_has_work(vitastor_c *client)
     return client->ringloop->has_work();
 }
 
-int vitastor_c_epoll_get_fd(vitastor_c *client)
-{
-    return !client->ringloop && client->epmgr ? client->epmgr->get_fd() : -1;
-}
-
-void vitastor_c_epoll_handle_events(vitastor_c *client, int timeout)
-{
-    return client->epmgr->handle_events(timeout);
-}
-
 void vitastor_c_read(vitastor_c *client, uint64_t inode, uint64_t offset, uint64_t len,
     struct iovec *iov, int iovcnt, VitastorReadHandler cb, void *opaque)
 {

src/vitastor_c.h

@@ -7,7 +7,7 @@
 #define VITASTOR_QEMU_PROXY_H
 
 // C API wrapper version
-#define VITASTOR_C_API_VERSION 3
+#define VITASTOR_C_API_VERSION 2
 
 #ifndef POOL_ID_BITS
 #define POOL_ID_BITS 16
@@ -40,7 +40,6 @@ vitastor_c *vitastor_c_create_qemu_uring(QEMUSetFDHandler *aio_set_fd_handler, v
 vitastor_c *vitastor_c_create_uring(const char *config_path, const char *etcd_host, const char *etcd_prefix,
     int use_rdma, const char *rdma_device, int rdma_port_num, int rdma_gid_index, int rdma_mtu, int log_level);
 vitastor_c *vitastor_c_create_uring_json(const char **options, int options_len);
-vitastor_c *vitastor_c_create_epoll_json(const char **options, int options_len);
 void vitastor_c_destroy(vitastor_c *client);
 int vitastor_c_is_ready(vitastor_c *client);
 int vitastor_c_uring_register_eventfd(vitastor_c *client);
@@ -48,8 +47,6 @@ void vitastor_c_uring_wait_ready(vitastor_c *client);
 void vitastor_c_uring_handle_events(vitastor_c *client);
 void vitastor_c_uring_wait_events(vitastor_c *client);
 int vitastor_c_uring_has_work(vitastor_c *client);
-int vitastor_c_epoll_get_fd(vitastor_c *client);
-void vitastor_c_epoll_handle_events(vitastor_c *client, int timeout);
 void vitastor_c_read(vitastor_c *client, uint64_t inode, uint64_t offset, uint64_t len,
     struct iovec *iov, int iovcnt, VitastorReadHandler cb, void *opaque);
 void vitastor_c_write(vitastor_c *client, uint64_t inode, uint64_t offset, uint64_t len, uint64_t check_version,