From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765312AbXGYMKy (ORCPT ); Wed, 25 Jul 2007 08:10:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762137AbXGYMIw (ORCPT ); Wed, 25 Jul 2007 08:08:52 -0400 Received: from rex.snapgear.com ([203.143.235.140]:33041 "EHLO snapgear.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1758301AbXGYMIu (ORCPT ); Wed, 25 Jul 2007 08:08:50 -0400 Date: Wed, 25 Jul 2007 22:07:20 +1000 From: Greg Ungerer Message-Id: <200707251207.l6PC7Ks4032174@goober> To: torvalds@linux-foundation.org Subject: [M68KNOMMU]: simplify ColdFire resume code Cc: gerg@uclinux.org, linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org It is useless to preserve THREAD_SR in `resume'. The real user's sr is actually in the stack. We also don't need to disable interrupts : we'll never be in an invalid state, the sp switch is atomic. Signed-off-by: Philippe De Muyter Signed-off-by: Greg Ungerer --- diff -Naur linux-2.6.22/arch/m68knommu/platform/5307/entry.S linux-2.6.22-uc0/arch/m68knommu/platform/5307/entry.S --- linux-2.6.22/arch/m68knommu/platform/5307/entry.S 2007-07-12 15:23:02.000000000 +1000 +++ linux-2.6.22-uc0/arch/m68knommu/platform/5307/entry.S 2007-07-12 15:27:01.000000000 +1000 @@ -235,16 +216,12 @@ * Beware - when entering resume, prev (the current task) is * in a0, next (the new task) is in a1,so don't change these * registers until their contents are no longer needed. + * This is always called in supervisor mode, so don't bother to save + * and restore sr; user's process sr is actually in the stack. */ ENTRY(resume) movel %a0, %d1 /* get prev thread in d1 */ - movew %sr,%d0 /* save thread status reg */ - movew %d0,%a0@(TASK_THREAD+THREAD_SR) - - oril #0x700,%d0 /* disable interrupts */ - move %d0,%sr - movel sw_usp,%d0 /* save usp */ movel %d0,%a0@(TASK_THREAD+THREAD_USP) @@ -255,7 +232,4 @@ movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore thread user stack */ movel %a0, sw_usp - - movew %a1@(TASK_THREAD+THREAD_SR),%d0 /* restore thread status reg */ - movew %d0, %sr rts