From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761869Ab0J2Uhi (ORCPT ); Fri, 29 Oct 2010 16:37:38 -0400 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:46238 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756391Ab0J2Uhf (ORCPT ); Fri, 29 Oct 2010 16:37:35 -0400 Date: Fri, 29 Oct 2010 13:37:59 -0700 (PDT) Message-Id: <20101029.133759.48489968.davem@davemloft.net> To: rostedt@goodmis.org Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, akpm@linux-foundation.org, fweisbec@gmail.com, jbaron@redhat.com, ddaney@caviumnetworks.com Subject: Re: [PATCH 4/8] jump label: Make arch_jump_label_text_poke_early() optional From: David Miller In-Reply-To: <20101028135647.822609872@goodmis.org> References: <20101028135548.055490014@goodmis.org> <20101028135647.822609872@goodmis.org> X-Mailer: Mew version 6.3 on Emacs 23.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt Date: Thu, 28 Oct 2010 09:55:52 -0400 > From: David Daney > > For the forthcoming MIPS jump label support, > arch_jump_label_text_poke_early() is unneeded as the MIPS NOP > instruction is already optimal. > > Supply a default implementation that does nothing. Flag x86 and SPARC > as having arch_jump_label_text_poke_early(). > > Cc: Jason Baron > Cc: David Miller > Signed-off-by: David Daney > LKML-Reference: <1286218615-24011-2-git-send-email-ddaney@caviumnetworks.com> > Signed-off-by: Steven Rostedt On the SPARC side, it's not that the nop isn't optimal, on sparc it's always 0x01000000. The issue is that when written an I-cache flush is necessary using a 'flushi' instruction. Does MIPS not need a flush when poking instructions? I find this hard to believe, although it's been some time since I last touched that architecture :-)