From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030568AbVLWQTE (ORCPT ); Fri, 23 Dec 2005 11:19:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932510AbVLWQSd (ORCPT ); Fri, 23 Dec 2005 11:18:33 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:51874 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S932505AbVLWQSK (ORCPT ); Fri, 23 Dec 2005 11:18:10 -0500 Date: Fri, 23 Dec 2005 17:17:23 +0100 From: Ingo Molnar To: lkml Cc: Linus Torvalds , Andrew Morton , Arjan van de Ven , Nicolas Pitre , Jes Sorensen , Zwane Mwaikambo , Oleg Nesterov , David Howells , Alan Cox , Benjamin LaHaise , Steven Rostedt , Christoph Hellwig , Andi Kleen , Russell King Subject: [patch 04/11] mutex subsystem, add include/asm-x86_64/mutex.h Message-ID: <20051223161723.GE26830@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -1.8 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.8 required=5.9 tests=ALL_TRUSTED,AWL autolearn=no SpamAssassin version=3.0.3 -2.8 ALL_TRUSTED Did not pass through any untrusted hosts 1.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org add the x86_64 version of mutex.h, optimized in assembly. Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven ---- include/asm-x86_64/mutex.h | 74 +++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 74 insertions(+) Index: linux/include/asm-x86_64/mutex.h =================================================================== --- /dev/null +++ linux/include/asm-x86_64/mutex.h @@ -0,0 +1,74 @@ +/* + * Assembly implementation of the mutex fastpath, based on atomic + * decrement/increment. + * + * started by Ingo Molnar: + * + * Copyright (C) 2004, 2005 Red Hat, Inc., Ingo Molnar + */ +#ifndef _ASM_MUTEX_H +#define _ASM_MUTEX_H + +/** + * __mutex_fastpath_lock - decrement and call function if negative + * @v: pointer of type atomic_t + * @fn: function to call if the result is negative + * + * Atomically decrements @v and calls if the result is negative. + */ +#define __mutex_fastpath_lock(v, fn_name) \ +do { \ + /* type-check the function too: */ \ + fastcall void (*__tmp)(atomic_t *) = fn_name; \ + unsigned long dummy; \ + \ + (void)__tmp; \ + typecheck(atomic_t *, v); \ + \ + __asm__ __volatile__( \ + LOCK "decl (%%rdi)\n" \ + "js 2f\n" \ + "1:\n" \ + LOCK_SECTION_START("") \ + "2: call "#fn_name"\n\t" \ + "jmp 1b\n" \ + LOCK_SECTION_END \ + :"=D" (dummy) \ + :"D" (v) \ + :"rax", "rsi", "rdx", "rcx", \ + "r8", "r9", "r10", "r11", "memory"); \ +} while (0) + +/** + * __mutex_fastpath_unlock - increment and call function if nonpositive + * @v: pointer of type atomic_t + * @fn: function to call if the result is nonpositive + * + * Atomically increments @v and calls if the result is nonpositive. + */ +#define __mutex_fastpath_unlock(v, fn_name) \ +do { \ + /* type-check the function too: */ \ + fastcall void (*__tmp)(atomic_t *) = fn_name; \ + unsigned long dummy; \ + \ + (void)__tmp; \ + typecheck(atomic_t *, v); \ + \ + __asm__ __volatile__( \ + LOCK "incl (%%rdi)\n" \ + "jle 2f\n" \ + "1:\n" \ + LOCK_SECTION_START("") \ + "2: call "#fn_name"\n\t" \ + "jmp 1b\n" \ + LOCK_SECTION_END \ + :"=D" (dummy) \ + :"D" (v) \ + :"rax", "rsi", "rdx", "rcx", \ + "r8", "r9", "r10", "r11", "memory"); \ +} while (0) + +#define __mutex_slowpath_needs_to_unlock() 1 + +#endif