Re: [PATCH] Add IORING_FEAT_FILES_SKIP feature flag

[Pavel Begunkov <asml.silence@gmail.com>]

On 5/20/21 10:55 PM, Drew DeVault wrote:
> On Thu May 20, 2021 at 9:32 AM EDT, Jens Axboe wrote:
>>> diff --git a/src/include/liburing/io_uring.h b/src/include/liburing/io_uring.h
>>> index 5a3cb90..091dcf7 100644
>>> --- a/src/include/liburing/io_uring.h
>>> +++ b/src/include/liburing/io_uring.h
>>> @@ -285,6 +285,7 @@ struct io_uring_params {
>>>  #define IORING_FEAT_SQPOLL_NONFIXED	(1U << 7)
>>>  #define IORING_FEAT_EXT_ARG		(1U << 8)
>>>  #define IORING_FEAT_NATIVE_WORKERS	(1U << 9)
>>> +#define IORING_FEAT_FILES_SKIP		IORING_FEAT_NATIVE_WORKERS
>>
>> I don't think this is a great idea. It can be used as a "probably we
>> have this feature" in userspace, but I don't like aliasing on the
>> kernel side.
> 
> This patch is for liburing, following the feedback on the kernel patch
> (which didn't alias, but regardless).

This file is a copy (almost) of the kernel's uapi header, so better be
off this file and have naming that wouldn't alias with names in this
header.

I think that's the problem Jens mean. Jens, is it? And I do still
believe it's a better way to not have an itchy one release gap
between actual feature introduction and new feat flag.

-- 
Pavel Begunkov