From mboxrd@z Thu Jan 1 00:00:00 1970 From: skannan@codeaurora.org (Saravana Kannan) Date: Tue, 20 Apr 2010 23:43:23 -0700 Subject: udelay() broken for SMP cores? In-Reply-To: References: <4BCE60C4.8020505@codeaurora.org> Message-ID: <4BCE9E8B.2070103@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org >> I looked at arch/arm/lib/delay.S and it looks like __udelay and >> __const_udelay won't work correctly for SMP cores. The code just uses >> the loops_per_jiffy variable instead of the per-CPU loops per jiffy data. >> >> Is anyone already working on a fix for that? If not, I can fix it up in >> a way that's hopefully palatable to the community. > > If you have case where individual CPUs are running at different speed and different > Tick rate then only this can make difference. Yes. I was talking about the case where the CPUs could be running at different speeds. Thanks, Saravana