Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-22 Thread David Miller
From: Nicolas Pitre Date: Tue, 20 Sep 2016 15:56:38 -0400 > Many embedded systems don't need the full POSIX timer support. > Configuring them out provides a nice kernel image size reduction. > > When POSIX timers are configured out, the PTP clock subsystem should be >

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-21 Thread Jiri Benc
On Wed, 21 Sep 2016 10:38:52 +0200, Richard Cochran wrote: > Embedded people like to optimize their systems. One pattern I have > more than once is that a multihomed design designates a special PTP > interface, often with a different HW than the other ports. PTP > support adds extra code into

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-21 Thread Jiri Benc
On Tue, 20 Sep 2016 23:09:52 +0200 (CEST), Thomas Gleixner wrote: > Now if you want to distangle PTP from a driver then you split it at the > driver level and not at the PTP level: > > DRIVER_X > tristate "Driver X" > > DRIVER_X_PTP > bool "Enable PTP

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-21 Thread Thomas Gleixner
On Tue, 20 Sep 2016, Nicolas Pitre wrote: > There are way more drivers than subsystems and if you had to go around > unselecting all NIC drivers for CONFIG_ETHERNET to be turned off, and > with CONFIG_ETHERNET=n you'd finally be able to turn networking off, > then this would be a nightmare.

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-21 Thread Richard Cochran
On Tue, Sep 20, 2016 at 06:47:02PM -0400, Nicolas Pitre wrote: > IMHO it is much nicer for the poor user configuring the kernel to have a > single configuration prompt for PTP support, and then have whatever > driver that can provide a PTP clock just do it (or omit it) based on > that single

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-20 Thread Nicolas Pitre
On Tue, 20 Sep 2016, Thomas Gleixner wrote: > I think the whole approach is wrong because it makes the PTP split at the > wrong level. > > Currently we have: > > DRIVER_X > tristate "Driver X" > select PTP > > In order to make POSIX_CLOCK configurable we should have >

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-20 Thread Thomas Gleixner
On Tue, 20 Sep 2016, Nicolas Pitre wrote: > On Tue, 20 Sep 2016, Richard Cochran wrote: > > > On Tue, Sep 20, 2016 at 10:25:56PM +0200, Richard Cochran wrote: > > > After this series, if I don't pay enough attention to dmesg, then I > > > have lost functionality that I had in step #1. That

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-20 Thread Nicolas Pitre
On Tue, 20 Sep 2016, Richard Cochran wrote: > On Tue, Sep 20, 2016 at 10:25:56PM +0200, Richard Cochran wrote: > > After this series, if I don't pay enough attention to dmesg, then I > > have lost functionality that I had in step #1. That sucks, and it has > > nothing to do with the tinification

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-20 Thread Nicolas Pitre
On Tue, 20 Sep 2016, Richard Cochran wrote: > On Tue, Sep 20, 2016 at 03:56:38PM -0400, Nicolas Pitre wrote: > > - Add a warning for the case where PTP clock subsystem is modular and a > > driver providing a clock is built-in rather than silently ignoring it. > > Suggested by Jiri Benc. > >

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-20 Thread Richard Cochran
On Tue, Sep 20, 2016 at 10:25:56PM +0200, Richard Cochran wrote: > After this series, if I don't pay enough attention to dmesg, then I > have lost functionality that I had in step #1. That sucks, and it has > nothing to do with the tinification option at all. It will bite even > if I have no

Re: [PATCH v2 0/2] make POSIX timers optional

2016-09-20 Thread Richard Cochran
On Tue, Sep 20, 2016 at 03:56:38PM -0400, Nicolas Pitre wrote: > - Add a warning for the case where PTP clock subsystem is modular and a > driver providing a clock is built-in rather than silently ignoring it. > Suggested by Jiri Benc. So I am really not happy with this. Here is a common