From patchwork Thu Apr 7 15:12:30 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Hocko X-Patchwork-Id: 8773881 Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id A0B28C0554 for ; Thu, 7 Apr 2016 15:13:43 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BF8D82026D for ; Thu, 7 Apr 2016 15:13:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D26342026F for ; Thu, 7 Apr 2016 15:13:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756707AbcDGPNh (ORCPT ); Thu, 7 Apr 2016 11:13:37 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:33305 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756157AbcDGPM4 (ORCPT ); Thu, 7 Apr 2016 11:12:56 -0400 Received: by mail-wm0-f65.google.com with SMTP id y144so5242925wmd.0; Thu, 07 Apr 2016 08:12:55 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=qoe9kg5YxndYJjQeKtW34uqB2pHGCxwJYWsNO2aobRw=; b=SfM3SQ8WiySS+M3zJDhtAby3gylNtvYOz7wMHWT8FTOa3zhTCiqGwrjrXZ6Btp3REL BhL+0hIaCnXvwnqdMjS8+Uhvi0G+oveui8+f6gfDRSPk3/KkrUCrPalsrknB46osvmtU OJbC9sP9ZjkPATxrtcXijPsFFbl+v1kUNa9IDwjUjjlDMA00uVsShSxqAjyiy2iBcPCg X9V+al2DTAmdko255yvNOBRfTIZgkz0kbJVCLWd85mDaPlajksS7AvYJwDM0lsRj20gT ASN6Y3Mnm/6TK840RmRPYDaaAbyNZdBPiN4cwsY3dY73xxookNMLr543FnkbFE6Fc47a sA+A== X-Gm-Message-State: AD7BkJKv8bgxLDxyzpXDEcJfjcUN3oRFlOn6flTv+om8NlVu9pdsjFS1WlNF2RRAppmVZg== X-Received: by 10.28.19.204 with SMTP id 195mr31899813wmt.1.1460041971809; Thu, 07 Apr 2016 08:12:51 -0700 (PDT) Received: from tiehlicka.suse.cz (nat1.scz.suse.com. [213.151.88.250]) by smtp.gmail.com with ESMTPSA id ks5sm8995472wjb.13.2016.04.07.08.12.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 07 Apr 2016 08:12:51 -0700 (PDT) From: Michal Hocko To: LKML Cc: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , "David S. Miller" , Tony Luck , Andrew Morton , Chris Zankel , Max Filippov , x86@kernel.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org, Michal Hocko Subject: [PATCH 10/11] x86, rwsem: provide __down_write_killable Date: Thu, 7 Apr 2016 17:12:30 +0200 Message-Id: <1460041951-22347-11-git-send-email-mhocko@kernel.org> X-Mailer: git-send-email 2.8.0.rc3 In-Reply-To: <1460041951-22347-1-git-send-email-mhocko@kernel.org> References: <1460041951-22347-1-git-send-email-mhocko@kernel.org> Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Michal Hocko which uses the same fast path as __down_write except it falls back to call_rwsem_down_write_failed_killable slow path and return -EINTR if killed. To prevent from code duplication extract the skeleton of __down_write into a helper macro which just takes the semaphore and the slow path function to be called. Signed-off-by: Michal Hocko --- arch/x86/include/asm/rwsem.h | 41 ++++++++++++++++++++++++++++------------- arch/x86/lib/rwsem.S | 8 ++++++++ 2 files changed, 36 insertions(+), 13 deletions(-) diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h index d79a218675bc..4c3d90dbe89a 100644 --- a/arch/x86/include/asm/rwsem.h +++ b/arch/x86/include/asm/rwsem.h @@ -99,21 +99,36 @@ static inline int __down_read_trylock(struct rw_semaphore *sem) /* * lock for writing */ +#define ____down_write(sem, slow_path) \ +({ \ + long tmp; \ + struct rw_semaphore* ret = sem; \ + asm volatile("# beginning down_write\n\t" \ + LOCK_PREFIX " xadd %1,(%2)\n\t" \ + /* adds 0xffff0001, returns the old value */ \ + " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" \ + /* was the active mask 0 before? */\ + " jz 1f\n" \ + " call " slow_path "\n" \ + "1:\n" \ + "# ending down_write" \ + : "+m" (sem->count), "=d" (tmp), "+a" (ret) \ + : "a" (sem), "1" (RWSEM_ACTIVE_WRITE_BIAS) \ + : "memory", "cc"); \ + ret; \ +}) + static inline void __down_write(struct rw_semaphore *sem) { - long tmp; - asm volatile("# beginning down_write\n\t" - LOCK_PREFIX " xadd %1,(%2)\n\t" - /* adds 0xffff0001, returns the old value */ - " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" - /* was the active mask 0 before? */ - " jz 1f\n" - " call call_rwsem_down_write_failed\n" - "1:\n" - "# ending down_write" - : "+m" (sem->count), "=d" (tmp) - : "a" (sem), "1" (RWSEM_ACTIVE_WRITE_BIAS) - : "memory", "cc"); + ____down_write(sem, "call_rwsem_down_write_failed"); +} + +static inline int __down_write_killable(struct rw_semaphore *sem) +{ + if (IS_ERR(____down_write(sem, "call_rwsem_down_write_failed_killable"))) + return -EINTR; + + return 0; } /* diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S index 40027db99140..d1a1397e1fb3 100644 --- a/arch/x86/lib/rwsem.S +++ b/arch/x86/lib/rwsem.S @@ -101,6 +101,14 @@ ENTRY(call_rwsem_down_write_failed) ret ENDPROC(call_rwsem_down_write_failed) +ENTRY(call_rwsem_down_write_failed_killable) + save_common_regs + movq %rax,%rdi + call rwsem_down_write_failed_killable + restore_common_regs + ret +ENDPROC(call_rwsem_down_write_failed_killable) + ENTRY(call_rwsem_wake) /* do nothing if still outstanding active readers */ __ASM_HALF_SIZE(dec) %__ASM_HALF_REG(dx)