All of lore.kernel.org
 help / color / mirror / Atom feed
From: John Stultz <john.stultz@linaro.org>
To: Nicolas Pitre <nico@fluxnic.net>, Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	lkml <linux-kernel@vger.kernel.org>,
	Richard Cochran <richardcochran@gmail.com>
Subject: Re: [RFC/PATCH] posix-timers: make them configurable
Date: Thu, 8 Sep 2016 14:19:24 -0700	[thread overview]
Message-ID: <CALAqxLXmbDgcc1oVZezzY=oRV4johPgxFNpWBBfO4Hk9tZiBJg@mail.gmail.com> (raw)
In-Reply-To: <alpine.LFD.2.20.1609081658570.14769@knanqh.ubzr>

On Thu, Sep 8, 2016 at 2:05 PM, Nicolas Pitre <nico@fluxnic.net> wrote:
>
> Small embedded systems typically don't need them.  This removes about
> 16KB from the kernel binary size on ARM when configured out.
> Corresponding syscalls are routed to a stub logging the attempt to
> use those syscalls which should be enough of a clue if they were
> disabled without proper consideration.
>
> Signed-off-by: Nicolas Pitre <nico@linaro.org>

Hrm... So being able to trim down the kernel is important.

Although my sense is that momentum has been moving to clock_gettime()
over gettimeofday(), such that gettimeofday() is mostly a shim over
clock_gettime() logic wise. So this is sort of going the other
direction.

Also given many other syscalls take clockids and the backing logic
isn't really getting removed (probably could cut the dynamic posix
clocks core with the same conditional), I wonder if you could get a
similar size win by taking a slightly more narrow cutting of the
subsystem. That way you could preserve the more useful clock_gettime()
functionality, but maybe stub out some of the less often used
functionality.

Josh (cc'ed) also was talking awhile back about cutting out the core
NTP logic. Having a single minimal-time option might be nice rather
then having a bunch of different conditionals that might be combined.

thanks
-john

  reply	other threads:[~2016-09-08 21:19 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-08 21:05 [RFC/PATCH] posix-timers: make them configurable Nicolas Pitre
2016-09-08 21:19 ` John Stultz [this message]
2016-09-08 21:48   ` Josh Triplett
     [not found]   ` <i7B1bN3EzSJWci7B2bJXya@videotron.ca>
2016-09-08 23:56     ` Nicolas Pitre
2016-09-09  0:37       ` Josh Triplett
2016-09-09  7:48   ` Richard Cochran
2016-09-09  8:00     ` Josh Triplett
2016-09-09 13:47       ` Thomas Gleixner
2016-09-09 13:46     ` Thomas Gleixner
2016-09-09 13:39 ` Thomas Gleixner
2016-09-13 20:57   ` Nicolas Pitre
2016-09-14  9:47     ` Thomas Gleixner

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='CALAqxLXmbDgcc1oVZezzY=oRV4johPgxFNpWBBfO4Hk9tZiBJg@mail.gmail.com' \
    --to=john.stultz@linaro.org \
    --cc=josh@joshtriplett.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nico@fluxnic.net \
    --cc=richardcochran@gmail.com \
    --cc=tglx@linutronix.de \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.