On Thu, Mar 4, 2021 at 11:19 AM Jens Axboe <axboe@xxxxxxxxx> wrote:
>
> Took a quick look at this, and I agree that's _much_ better. In fact, it
> boils down to just calling copy_process() and then having the caller do
> wake_up_new_task(). So not sure if it's worth adding an
> create_io_thread() helper, or just make copy_process() available
> instead. This is ignoring the trace point for now...
I really don't want to expose copy_process() outside of kernel/fork.c.
The whole three-phase "copy - setup - activate" model is a really
really good thing, and it's how we've done things internally almost
forever, but I really don't want to expose those middle stages to any
outsiders.
So I'd really prefer a simple new "create_io_worker()", even if it's
literally just some four-line function that does
p = copy_process(..);
if (!IS_ERR(p)) {
block all signals in p
set PF_IO_WORKER flag
wake_up_new_task(p);
}
return p;
I very much want that to be inside kernel/fork.c and have all these
rules about creating new threads localized there.
Linus
