From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 487026B0044 for ; Mon, 21 Dec 2009 04:10:52 -0500 (EST) Date: Mon, 21 Dec 2009 09:07:50 +0000 From: Russell King - ARM Linux Subject: Re: CPU consumption is going as high as 95% on ARM Cortex A8 Message-ID: <20091221090750.GA11669@n2100.arm.linux.org.uk> References: <19F8576C6E063C45BE387C64729E73940449F43857@dbde02.ent.ti.com> <20091217095641.GA399@n2100.arm.linux.org.uk> <19F8576C6E063C45BE387C64729E73940449F43E29@dbde02.ent.ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <19F8576C6E063C45BE387C64729E73940449F43E29@dbde02.ent.ti.com> Sender: owner-linux-mm@kvack.org To: "Hiremath, Vaibhav" Cc: "linux-arm-kernel@lists.infradead.org" , "linux-mm@kvack.org" , "linux-omap@vger.kernel.org" List-ID: On Mon, Dec 21, 2009 at 11:56:23AM +0530, Hiremath, Vaibhav wrote: > > vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > > > > will result in the memory being mapped as 'Strongly Ordered', > > resulting > > in there being multiple mappings with differing types. In later > > kernels, we have pgprot_dmacoherent() and I'd suggest changing the > > above > > macro for that. > > > > I tried with your suggestion above but unfortunately it didn't work for > me. I am seeing the same behavior with the pgprot_dmacoherent(). I > pulled your patch (which got applied cleanly on 2.6.32-rc5) - What happens if you comment out the pgprot_dmacoherent() / pgprot_noncached() line completely? I suspect that will "solve" the problem - but you'll then no longer have DMA coherency with userspace, so its not really a solution. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org