/*
- * null engine - doesn't do any transfers. Used to test fio.
+ * null engine
+ *
+ * IO engine that doesn't do any real IO transfers, it just pretends to.
+ * The main purpose is to test fio itself.
+ *
+ * It also can act as external C++ engine - compiled with:
+ *
+ * g++ -O2 -g -shared -rdynamic -fPIC -o cpp_null null.c -DFIO_EXTERNAL_ENGINE
+ *
+ * to test it execute:
+ *
+ * LD_LIBRARY_PATH=./engines ./fio examples/cpp_null.fio
*
*/
#include <stdio.h>
#include <assert.h>
#include "../fio.h"
-#include "../os.h"
-static int fio_null_queue(struct thread_data fio_unused *td, struct io_u *io_u)
+struct null_data {
+ struct io_u **io_us;
+ int queued;
+ int events;
+};
+
+static struct io_u *null_event(struct null_data *nd, int event)
+{
+ return nd->io_us[event];
+}
+
+static int null_getevents(struct null_data *nd, unsigned int min_events,
+ unsigned int fio_unused max,
+ const struct timespec fio_unused *t)
+{
+ int ret = 0;
+
+ if (min_events) {
+ ret = nd->events;
+ nd->events = 0;
+ }
+
+ return ret;
+}
+
+static int null_commit(struct thread_data *td, struct null_data *nd)
+{
+ if (!nd->events) {
+#ifndef FIO_EXTERNAL_ENGINE
+ io_u_mark_submit(td, nd->queued);
+#endif
+ nd->events = nd->queued;
+ nd->queued = 0;
+ }
+
+ return 0;
+}
+
+static int null_queue(struct thread_data *td, struct null_data *nd,
+ struct io_u *io_u)
+{
+ fio_ro_check(td, io_u);
+
+ if (td->io_ops->flags & FIO_SYNCIO)
+ return FIO_Q_COMPLETED;
+ if (nd->events)
+ return FIO_Q_BUSY;
+
+ nd->io_us[nd->queued++] = io_u;
+ return FIO_Q_QUEUED;
+}
+
+static int null_open(struct null_data fio_unused *nd,
+ struct fio_file fio_unused *f)
{
- io_u->resid = 0;
- io_u->error = 0;
- return FIO_Q_COMPLETED;
+ return 0;
+}
+
+static void null_cleanup(struct null_data *nd)
+{
+ if (nd) {
+ free(nd->io_us);
+ free(nd);
+ }
+}
+
+static int null_init(struct thread_data *td, struct null_data **nd_ptr)
+{
+ struct null_data *nd = (struct null_data *) malloc(sizeof(**nd_ptr));
+
+ memset(nd, 0, sizeof(*nd));
+
+ if (td->o.iodepth != 1) {
+ nd->io_us = (struct io_u **) malloc(td->o.iodepth * sizeof(struct io_u *));
+ memset(nd->io_us, 0, td->o.iodepth * sizeof(struct io_u *));
+ } else
+ td->io_ops->flags |= FIO_SYNCIO;
+
+ *nd_ptr = nd;
+ return 0;
+}
+
+#ifndef __cplusplus
+
+static struct io_u *fio_null_event(struct thread_data *td, int event)
+{
+ return null_event((struct null_data *)td->io_ops_data, event);
+}
+
+static int fio_null_getevents(struct thread_data *td, unsigned int min_events,
+ unsigned int max, const struct timespec *t)
+{
+ struct null_data *nd = (struct null_data *)td->io_ops_data;
+ return null_getevents(nd, min_events, max, t);
+}
+
+static int fio_null_commit(struct thread_data *td)
+{
+ return null_commit(td, (struct null_data *)td->io_ops_data);
+}
+
+static int fio_null_queue(struct thread_data *td, struct io_u *io_u)
+{
+ return null_queue(td, (struct null_data *)td->io_ops_data, io_u);
+}
+
+static int fio_null_open(struct thread_data *td, struct fio_file *f)
+{
+ return null_open((struct null_data *)td->io_ops_data, f);
+}
+
+static void fio_null_cleanup(struct thread_data *td)
+{
+ null_cleanup((struct null_data *)td->io_ops_data);
+}
+
+static int fio_null_init(struct thread_data *td)
+{
+ return null_init(td, (struct null_data **)&td->io_ops_data);
}
static struct ioengine_ops ioengine = {
.name = "null",
.version = FIO_IOOPS_VERSION,
.queue = fio_null_queue,
- .flags = FIO_SYNCIO | FIO_NULLIO,
+ .commit = fio_null_commit,
+ .getevents = fio_null_getevents,
+ .event = fio_null_event,
+ .init = fio_null_init,
+ .cleanup = fio_null_cleanup,
+ .open_file = fio_null_open,
+ .flags = FIO_DISKLESSIO | FIO_FAKEIO,
};
static void fio_init fio_null_register(void)
{
unregister_ioengine(&ioengine);
}
+
+#else
+
+#ifdef FIO_EXTERNAL_ENGINE
+
+struct NullData {
+ NullData(struct thread_data *td)
+ {
+ null_init(td, &impl_);
+ }
+
+ ~NullData()
+ {
+ null_cleanup(impl_);
+ }
+
+ static NullData *get(struct thread_data *td)
+ {
+ return reinterpret_cast<NullData *>(td->io_ops_data);
+ }
+
+ io_u *fio_null_event(struct thread_data *, int event)
+ {
+ return null_event(impl_, event);
+ }
+
+ int fio_null_getevents(struct thread_data *, unsigned int min_events,
+ unsigned int max, const struct timespec *t)
+ {
+ return null_getevents(impl_, min_events, max, t);
+ }
+
+ int fio_null_commit(struct thread_data *td)
+ {
+ return null_commit(td, impl_);
+ }
+
+ int fio_null_queue(struct thread_data *td, struct io_u *io_u)
+ {
+ return null_queue(td, impl_, io_u);
+ }
+
+ int fio_null_open(struct thread_data *, struct fio_file *f)
+ {
+ return null_open(impl_, f);
+ }
+
+ struct null_data *impl_;
+};
+
+extern "C" {
+
+static struct io_u *fio_null_event(struct thread_data *td, int event)
+{
+ return NullData::get(td)->fio_null_event(td, event);
+}
+
+static int fio_null_getevents(struct thread_data *td, unsigned int min_events,
+ unsigned int max, const struct timespec *t)
+{
+ return NullData::get(td)->fio_null_getevents(td, min_events, max, t);
+}
+
+static int fio_null_commit(struct thread_data *td)
+{
+ return NullData::get(td)->fio_null_commit(td);
+}
+
+static int fio_null_queue(struct thread_data *td, struct io_u *io_u)
+{
+ return NullData::get(td)->fio_null_queue(td, io_u);
+}
+
+static int fio_null_open(struct thread_data *td, struct fio_file *f)
+{
+ return NullData::get(td)->fio_null_open(td, f);
+}
+
+static int fio_null_init(struct thread_data *td)
+{
+ td->io_ops_data = new NullData(td);
+ return 0;
+}
+
+static void fio_null_cleanup(struct thread_data *td)
+{
+ delete NullData::get(td);
+}
+
+static struct ioengine_ops ioengine;
+void get_ioengine(struct ioengine_ops **ioengine_ptr)
+{
+ *ioengine_ptr = &ioengine;
+
+ ioengine.name = "cpp_null";
+ ioengine.version = FIO_IOOPS_VERSION;
+ ioengine.queue = fio_null_queue;
+ ioengine.commit = fio_null_commit;
+ ioengine.getevents = fio_null_getevents;
+ ioengine.event = fio_null_event;
+ ioengine.init = fio_null_init;
+ ioengine.cleanup = fio_null_cleanup;
+ ioengine.open_file = fio_null_open;
+ ioengine.flags = FIO_DISKLESSIO | FIO_FAKEIO;
+}
+}
+#endif /* FIO_EXTERNAL_ENGINE */
+
+#endif /* __cplusplus */