From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King Subject: Re: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb Date: Thu, 17 May 2012 10:51:24 +0100 Message-ID: <20120517095124.GN23420@flint.arm.linux.org.uk> References: <20110302175928.022902359@chello.nl> <20110302180259.109909335@chello.nl> <20120517030551.GA11623@linux-sh.org> <20120517093022.GA14666@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20120517093022.GA14666@arm.com> Sender: owner-linux-mm@kvack.org To: Catalin Marinas Cc: Paul Mundt , Peter Zijlstra , Andrea Arcangeli , Thomas Gleixner , Rik van Riel , Ingo Molnar , "akpm@linux-foundation.org" , Linus Torvalds , "linux-kernel@vger.kernel.org" , "linux-arch@vger.kernel.org" , "linux-mm@kvack.org" , Benjamin Herrenschmidt , David Miller , Hugh Dickins , Mel Gorman , Nick Piggin , Chris Metcalf , Martin Schwidefsky List-Id: linux-arch.vger.kernel.org On Thu, May 17, 2012 at 10:30:23AM +0100, Catalin Marinas wrote: > Another minor thing is that on newer ARM processors (Cortex-A15) we > need the TLB shootdown even on UP systems, so tlb_fast_mode should > always return 0. Something like below (untested): No Catalin, we need this for virtually all ARMv7 CPUs whether they're UP or SMP, not just for A15, because of the speculative prefetch which can re-load TLB entries from the page tables at _any_ time. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from caramon.arm.linux.org.uk ([78.32.30.218]:37914 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760054Ab2EQJxM (ORCPT ); Thu, 17 May 2012 05:53:12 -0400 Date: Thu, 17 May 2012 10:51:24 +0100 From: Russell King Subject: Re: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb Message-ID: <20120517095124.GN23420@flint.arm.linux.org.uk> References: <20110302175928.022902359@chello.nl> <20110302180259.109909335@chello.nl> <20120517030551.GA11623@linux-sh.org> <20120517093022.GA14666@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120517093022.GA14666@arm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Catalin Marinas Cc: Paul Mundt , Peter Zijlstra , Andrea Arcangeli , Thomas Gleixner , Rik van Riel , Ingo Molnar , "akpm@linux-foundation.org" , Linus Torvalds , "linux-kernel@vger.kernel.org" , "linux-arch@vger.kernel.org" , "linux-mm@kvack.org" , Benjamin Herrenschmidt , David Miller , Hugh Dickins , Mel Gorman , Nick Piggin , Chris Metcalf , Martin Schwidefsky Message-ID: <20120517095124.Y6ISf5hyRAefBEbIZnZ9_Nhe75CNjGglFN556Lq-NZA@z> On Thu, May 17, 2012 at 10:30:23AM +0100, Catalin Marinas wrote: > Another minor thing is that on newer ARM processors (Cortex-A15) we > need the TLB shootdown even on UP systems, so tlb_fast_mode should > always return 0. Something like below (untested): No Catalin, we need this for virtually all ARMv7 CPUs whether they're UP or SMP, not just for A15, because of the speculative prefetch which can re-load TLB entries from the page tables at _any_ time. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: