From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Stultz Subject: Re: Minimum timing resolution in Ubuntu/Linaro on the PandaBoard ES Date: Wed, 08 Feb 2012 08:58:42 -0800 Message-ID: <1328720322.8119.7.camel@js-netbook> References: <4F31A91B.8080106@umich.edu> <4F32063F.1020607@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4F32063F.1020607-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linaro-dev-bounces-cunTk1MwBs8s++Sfvej+rw@public.gmane.org Errors-To: linaro-dev-bounces-cunTk1MwBs8s++Sfvej+rw@public.gmane.org To: Dmitry Antipov Cc: Andrew Richardson , linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linaro-dev-cunTk1MwBs8s++Sfvej+rw@public.gmane.org List-Id: linux-omap@vger.kernel.org On Tue, 2012-02-07 at 21:21 -0800, Dmitry Antipov wrote: > BTW, I have no ideas why clock_getres(CLOCK_REALTIME,...) returns {0, 1} > regardless of underlying clock source. I expect {0, 30517} for 32K timer > and {0, 26} for MPU timer. Yea. I had proposed to export the underlying clocksource's resolution via clock_getres, but it was argued against. The concern is that applications might not expect clock_getres to change while the application is running. Between any clock_getres() call and a time read, the clocksources could change. But if someone has a different reading of the posix spec, it might be good to revisit this. thanks -john