On Tue, Apr 27, 2021 at 08:58:32PM +0200, Niklas Cassel wrote: > Hello there, > > > If running fio with --create_serialize=1 and --numjobs=2 > > ->setup() callback will be called for each thread, > before the ->init() callback is called for each thread: > > my_fio_setup: td: 0x7eff72d6a000 > my_fio_setup: td: 0x7eff72daea70 > my_fio_init: td: 0x7eff72d6a000 > my_fio_init: td: 0x7eff72daea70 > > However, if running fio with --create_serialize=0 and --numjobs=2 > you will instead see that ->init() callback will be called for each > thread, before the ->setup() callback is called for each thread: > > my_fio_init: td: 0x7eff72d6a000 > my_fio_init: td: 0x7eff72daea70 > my_fio_setup: td: 0x7eff72d6a000 > my_fio_setup: td: 0x7eff72daea70 > > > This is because, in backend.c:thread_main() looks like this: > > ... > > if (!init_iolog(td)) > goto err; > > if (td_io_init(td)) > goto err; > > if (init_io_u(td)) > goto err; > > ... > > if (!o->create_serialize && setup_files(td)) > goto err; > > if (!init_random_map(td)) > goto err; > > ... > > > > td_io_init() will call td->io_ops->init(td) and setup_files() will > call td->io_ops->setup(td). > > Is it just me who thinks that it is extremely confusing for an ioengine > developer to not be able to know if the ->setup() or ->init() callback > will be called first? > > Should we perhaps consider moving the > > if (!o->create_serialize && setup_files(td)) > goto err; > > chunk so that it is before the td_io_init() call? > > That way, ->setup() would always be called before ->init() > (which is the default, since --create_serialize defaults to 1), > no matter what value --create_serialize is set to. > > > Kind regards, > Niklas Hello Jens, any thoughts on this? Kind regards, Niklas
