From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id 498C46B007E for ; Wed, 4 May 2016 09:53:48 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id e201so49319731wme.1 for ; Wed, 04 May 2016 06:53:48 -0700 (PDT) Received: from mail.free-electrons.com (down.free-electrons.com. [37.187.137.238]) by mx.google.com with ESMTP id dc5si5056267wjb.14.2016.05.04.06.53.47 for ; Wed, 04 May 2016 06:53:47 -0700 (PDT) Date: Wed, 4 May 2016 15:53:45 +0200 From: Thomas Petazzoni Subject: Re: kmap_atomic and preemption Message-ID: <20160504155345.5fdd366e@free-electrons.com> In-Reply-To: <20160504134729.GP3430@twins.programming.kicks-ass.net> References: <5729D0F4.9090907@synopsys.com> <20160504134729.GP3430@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Peter Zijlstra Cc: Vineet Gupta , Nicolas Pitre , Andrew Morton , David Hildenbrand , Russell King , lkml , "linux-mm@kvack.org" , "linux-arch@vger.kernel.org" Hello, On Wed, 4 May 2016 15:47:29 +0200, Peter Zijlstra wrote: > static inline void *kmap_atomic(struct page *page) > { > preempt_disable(); > pagefault_disable(); > if (!PageHighMem(page)) > return page_address(page); > > return __kmap_atomic(page); > } This is essentially what has been done on ARM in commit 9ff0bb5ba60638a688a46e93df8c5009896672eb, showing a pretty significant improvement in network workloads. Best regards, Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- 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