On 25/01/2021 16:00, Jens Axboe wrote: > On 1/25/21 4:42 AM, Pavel Begunkov wrote: >> struct io_submit_state is quite big (168 bytes) and going to grow. It's >> better to not keep it on stack as it is now. Move it to context, it's >> always protected by uring_lock, so it's fine to have only one instance >> of it. > > I don't like this one. Unless you have plans to make it much bigger, > I think it should stay on the stack. On the stack, the ownership is > clear. Thinking of it, it's not needed for this series, just traversing a list twice is not nice but bearable. For experiments I was using its persistency across syscalls + grew it to 32 to match up completion flush (allocating still by 8) to add req memory reuse, but that's out of scope of these patches. I haven't got a strong opinion on that one yet, even though alloc/dealloc are pretty heavy, this approach may loose allocation locality. -- Pavel Begunkov
