From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Subject: Re: Need for a new spinlock API? Date: Thu, 22 Mar 2007 09:51:47 +0100 Message-ID: <1174553507.1158.160.camel@laptopd505.fenrus.org> References: <1174462330.1158.113.camel@laptopd505.fenrus.org> <623132dc0703211159n3781bfbdu6ffd43743a6fe377@mail.gmail.com> <1174511009.1158.150.camel@laptopd505.fenrus.org> <677342AB6AE12D4DB59A9D473F40D74B028E0441@xmb-blr-416.apac.cisco.com> <677342AB6AE12D4DB59A9D473F40D74B028E0442@xmb-blr-416.apac.cisco.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-newbie-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii" To: Rajat Jain Cc: "Ajay Singh (ajaysi)" , anubhav rakshit , kernel mail , newbie On Thu, 2007-03-22 at 11:29 +0530, Rajat Jain wrote: > > The lock contention is between the process or another instance of same > > ISR on other processor(say uP1) which are waiting for that same spinlock > > to be released. They will have to wait till old ISR instance finishes on > > processor (say uP0). > > No, by design there cannot be two instances of your ISR running on two > seperate processes (since the interrupt is disabled on all processors > untill the ISR returns). but the USERCONTEXT on the other cpu ALSO uses this lock, right? (Otherwise this entire discussion was moot already, that was your initial premise) -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org - To unsubscribe from this list: send the line "unsubscribe linux-newbie" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs