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Date:   Wed, 21 Jun 2023 23:08:15 +0700
From:   Ammar Faizi <ammarfaizi2@gnuweeb.org>
To:     Guillem Jover <guillem@hadrons.org>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        io-uring Mailing List <io-uring@vger.kernel.org>,
        Jens Axboe <axboe@kernel.dk>, Jeff Moyer <jmoyer@redhat.com>,
        Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>
Subject: Re: False positives in nolibc check
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On Wed, Jun 21, 2023 at 01:51:56PM +0200, Guillem Jover wrote:
> So, I also think I'd appreciate a --use-libc mode (or similar) which I'd
> probably consider enabling for Debian.

I'll send a patch to add that mode for review tomorrow morning.

> OTOH, I've no idea how much impact that would cause to performance? Do
> any of you have numbers?

The only real *hot path* that depended on a libc function was
io_uring_submit(). It used syscall(2) function.

But now even when compiled with libc, we no longer use syscall(2),
instead we use inline assembly to invoke syscall. So there is nothing to
worry about performance here.

Side note:
liburing still uses syscall(2) on architectures other than x86, x86-64
and aarch64.

-- 
Ammar Faizi