From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4666B6AE.2070209@domain.hid> Date: Wed, 06 Jun 2007 15:29:18 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 References: <46649F7E.3060104@domain.hid> <46651F7D.9090702@domain.hid> <4666AD52.1050101@domain.hid> In-Reply-To: <4666AD52.1050101@domain.hid> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-core] [PATCH-STACK] Updates, timerstats, rtdm-timers List-Id: "Xenomai life and development \(bug reports, patches, discussions\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: xenomai-core Jan Kiszka wrote: > Jan Kiszka wrote: > >>Jan Kiszka wrote: >>... >> >>>fast-tsc-to-ns-v2.patch >>> >>> [Rebased, improved rounding of least significant digit] >> >>Rounding in the fast path for the sake of the last digit was silly. >>Instead, I'm now addressing the ugly interval printing via >>xnarch_precise_tsc_to_ns when converting the timer interval back into >>nanos. -v3 incorporating this has just been uploaded. >> > > > After noticing yesterday that even unpatched Xenomai sometimes converts > inaccurately when showing small timer intervals under /proc, I just got > an idea how to address this beautification issue even better: -v4 now > rounds up in the slow, precise tsc-to-ns path, see > > http://www.rts.uni-hannover.de/rtaddon/patches/xenomai/fast-tsc-to-ns-v4.patch I am the one who decided of the rounding behaviour of llimd, RTAI version had the same rounding policy as the one you propose, and I made it for the following reasons: - rouding towards 0 is the policy used by the C language, so doing this for llimd made it consistent with what one expects from C code; - values computed by llimd are used to program timers, and we prefer the timer to be programmed for a too short value than for a too long value. -- Gilles Chanteperdrix