From: Ingo Molnar <mingo@kernel.org>
To: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: linux-kernel@vger.kernel.org, Al Viro <viro@zeniv.linux.org.uk>,
Andi Kleen <ak@linux.intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Andy Lutomirski <luto@kernel.org>,
Brian Gerst <brgerst@gmail.com>,
Denys Vlasenko <dvlasenk@redhat.com>,
"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
x86@kernel.org, Maninder Singh <maninder1.s@samsung.com>,
Arnd Bergmann <arnd@arndb.de>,
linux-arch <linux-arch@vger.kernel.org>
Subject: Re: [PATCH 0/3] syscalls: clean up stub naming convention
Date: Mon, 9 Apr 2018 09:06:11 +0200 [thread overview]
Message-ID: <20180409070611.43iq66eay2ctwv2m@gmail.com> (raw)
In-Reply-To: <20180409064511.ejhfqcurtlq2srq5@gmail.com>
* Ingo Molnar <mingo@kernel.org> wrote:
>
> * Dominik Brodowski <linux@dominikbrodowski.net> wrote:
>
> > On Sun, Apr 08, 2018 at 10:35:50AM +0200, Ingo Molnar wrote:
> > > - _____sys_waitid() # ridiculous number of underscores?
> > > - __sys_waitid() # too generic sounding?
> >
> > ... and we'd need to rename internal helpers in net/
> >
> > > - __inline_sys_waitid() # too long?
> >
> > sounds acceptable, though a bit long (especially for the compat case, though
> > it doesn't really matter in the case of
> > __inline_compat_sys_sched_rr_get_interval)
>
> So as per the previous mail this is not just an inline function, but an active
> type conversion wrapper that sign-extends 32-bit ints to longs, which is important
> on some 64-bit architectures.
>
> And that's a really non-obvious property IMO, and the name should probably reflect
> _that_ non-obvious property, not the inlining property which is really just a
> small detail.
>
> I.e. how about:
>
> __se_sys_waitid()
>
> ... where 'se' stands for sign-extended, with a comment in the macro that explains
> the prefix? (The historical abbreviation for sign extension is 'sext', which I
> think wouldn't really be suitable these days.)
Ok, so I got confused there: I think it's the do_sys_waitid() intermediate that
is actually doing the sign-extension - and the inlined helper is what is in the
syscall definition body.
So it's all still somewhat of a confusing misnomer: the 'do' named function is
actually the sign-extension function variant - and the '_il' variant actually
'does' the real work ...
I.e., old naming:
810f08d0 t kernel_waitid # common C function (see kernel/exit.c)
<inline> __il_sys_waitid # inlined helper doing the actual work
# (takes parameters as declared)
810f1aa0 T __do_sys_waitid # C function calling inlined helper
# (takes parameters of type long; casts
# them to the declared type)
810f1aa0 T sys_waitid # alias to __do_sys_waitid() (taking
# parameters as declared), to be included
# in syscall table
New suggested naming:
810f08d0 t kernel_waitid # common C function (see kernel/exit.c)
<inline> __do_sys_waitid # inlined helper doing the actual work
# (takes original parameters as declared)
810f1aa0 T __se_sys_waitid # sign-extending C function calling inlined
# helper (takes parameters of type long;
# casts them to the declared type)
810f1aa0 T sys_waitid # alias to __se_sys_waitid() (but taking
# original parameters as declared), to be
# included in syscall table
Agreed?
Thanks,
Ingo
next prev parent reply other threads:[~2018-04-09 7:06 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-07 7:46 [PATCH 0/3] syscalls: clean up stub naming convention Dominik Brodowski
2018-04-07 7:46 ` [PATCH 1/3] syscalls: clean up syscall " Dominik Brodowski
2018-04-07 7:46 ` [PATCH 2/3] syscalls: clean up compat " Dominik Brodowski
2018-04-07 7:46 ` [PATCH 3/3] syscalls: rename struct pt_regs-based sys_*() to __x64_sys_*() Dominik Brodowski
2018-04-08 8:35 ` [PATCH 0/3] syscalls: clean up stub naming convention Ingo Molnar
2018-04-08 9:15 ` Dominik Brodowski
2018-04-08 19:59 ` Dominik Brodowski
2018-04-08 20:06 ` [PATCH 4/3] syscalls/x86: adapt syscall_wrapper.h to the new syscall " Dominik Brodowski
2018-04-09 6:49 ` [PATCH 0/3] syscalls: clean up " Ingo Molnar
2018-04-09 6:54 ` Dominik Brodowski
2018-04-09 6:39 ` Ingo Molnar
2018-04-09 19:13 ` Linus Torvalds
2018-04-09 6:45 ` Ingo Molnar
2018-04-09 6:53 ` Dominik Brodowski
2018-04-09 7:06 ` Ingo Molnar [this message]
2018-04-09 7:08 ` Dominik Brodowski
2018-04-09 7:34 ` Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180409070611.43iq66eay2ctwv2m@gmail.com \
--to=mingo@kernel.org \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=brgerst@gmail.com \
--cc=dvlasenk@redhat.com \
--cc=hpa@zytor.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@dominikbrodowski.net \
--cc=luto@kernel.org \
--cc=maninder1.s@samsung.com \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=viro@zeniv.linux.org.uk \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).