From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 95F389000C2 for ; Thu, 7 Jul 2011 08:38:52 -0400 (EDT) Date: Thu, 7 Jul 2011 13:38:25 +0100 From: Russell King - ARM Linux Subject: Re: [PATCH 3/8] ARM: dma-mapping: use asm-generic/dma-mapping-common.h Message-ID: <20110707123825.GO8286@n2100.arm.linux.org.uk> References: <1308556213-24970-1-git-send-email-m.szyprowski@samsung.com> <201106241736.43576.arnd@arndb.de> <000601cc34c4$430f91f0$c92eb5d0$%szyprowski@samsung.com> <201106271519.43581.arnd@arndb.de> <20110707120918.GF7810@wantstofly.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110707120918.GF7810@wantstofly.org> Sender: owner-linux-mm@kvack.org List-ID: To: Lennert Buytenhek Cc: Arnd Bergmann , Marek Szyprowski , linux-arm-kernel@lists.infradead.org, linaro-mm-sig@lists.linaro.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, 'Kyungmin Park' , 'Joerg Roedel' On Thu, Jul 07, 2011 at 02:09:18PM +0200, Lennert Buytenhek wrote: > On Mon, Jun 27, 2011 at 03:19:43PM +0200, Arnd Bergmann wrote: > > > > > I suppose for the majority of the cases, the overhead of the indirect > > > > function call is near-zero, compared to the overhead of the cache > > > > management operation, so it would only make a difference for coherent > > > > systems without an IOMMU. Do we care about micro-optimizing those? > > FWIW, when I was hacking on ARM access point routing performance some > time ago, turning the L1/L2 cache maintenance operations into inline > functions (inlined into the ethernet driver) gave me a significant and > measurable performance boost. On what architecture? Can you show what you did to gain that? -- 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