From mboxrd@z Thu Jan 1 00:00:00 1970 From: john stultz Subject: Re: [PATCH V7 1/8] ntp: add ADJ_SETOFFSET mode bit Date: Tue, 21 Dec 2010 13:59:44 -0800 Message-ID: <1292968784.2618.51.camel@work-vm> References: <880d82bb8120f73973db27e0c48e949014b1a106.1292512461.git.richard.cochran@omicron.at> <1292960224.2618.4.camel@work-vm> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Kuwahara,T." <6vvetjsrt26xsrzlh1z0zn4d2grdah-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Alexander Gordeev , Rodolfo Giometti Cc: Richard Cochran , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Alan Cox , Arnd Bergmann , Christoph Lameter , David Miller , Krzysztof Halasa , Peter Zijlstra , Rodolfo Giometti , Thomas Gleixner List-Id: linux-api@vger.kernel.org On Wed, 2010-12-22 at 06:13 +0900, Kuwahara,T. wrote: > On Wed, Dec 22, 2010 at 4:37 AM, john stultz wrote: > > adjtimex is a linux specific interface, which is compatible but not > > identical to the ntp specified interfaces. The ntp client code already > > has Linux specific modifications, so I don't think we have to worry > > about 0x40 specifically being reserved by the NTP client. > > But struct timex is not linux-specific... It is if you're compiling against linux's timex.h file. We already have a number of differences compared with BSD's timex mode definitions: We have ADJ_TICK: 0x4000, which is MOD_CLKB in FreeBSD. We also have ADJ_OFFSET_SINGLESHOT and ADJ_OFFSET_SS_READ which allow adjtimex act like the original ntp_adjtime. The key bit is that we map the shared MOD_* definitions that the NTP client uses to the linux specific ADJ_* values in the linux timex.h However, your concern does bring up a good point: 0x40 is MOD_PPSMAX in BSD, and we should at-least check to make sure that the PPS code that is currently floating around on the lists and is in akpm's tree hasn't already reserved that bit. Rodolfo, Alexander: Any comments here? thanks -john