Re: [PATCH 05/18] Add io_uring IO interface

On 1/29/19 9:18 AM, Arnd Bergmann wrote:

On Tue, Jan 29, 2019 at 4:20 PM Jens Axboe [off-list ref] wrote:

quoted

On 1/29/19 4:58 AM, Arnd Bergmann wrote:

quoted

On Tue, Jan 29, 2019 at 7:30 AM Christoph Hellwig [off-list ref] wrote:

quoted

quoted

On Mon, Jan 28, 2019 at 11:25:12AM -0700, Jens Axboe wrote:

quoted

Especially with poll support now in the series, don't we need a ѕigmask
argument similar to pselect/ppoll/io_pgetevents now to deal with signal
blocking during waiting for events?

Is there any way to avoid passing in the sigset_t size? If it's just a
32-bit/64-bit thing, surely the in_compat_syscall() could cover it? Or
are there other cases that need to be catered to?

As far as I can tell we never look at it, never looked at it and don't
have any plans to look at it anytime soon.  But when I tried to omit
it for io_pgetevents I got stong pushback and thus had to add the
crazy double indirection calling convention.

That's good info. I am currently using set_user_sigmask() for it.
I'd really like to avoid having to pass in a sigset_t size for the
system call, however.

I really wouldn't do it, given that all other signal handling interfaces
are prepared for longer signal masks. You /could/ probably extend
it later with a flags bit to signify a longer mask instead of using
the entire register to hold the bit length, it just seems really
inconsistent with all other system calls.

Damnit! OK, I'll keep what I currently have then.

-- 
Jens Axboe

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