From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C638FC43387 for ; Thu, 3 Jan 2019 14:18:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D02820815 for ; Thu, 3 Jan 2019 14:18:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="L5xO1kq4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730780AbfACOSW (ORCPT ); Thu, 3 Jan 2019 09:18:22 -0500 Received: from mail-it1-f194.google.com ([209.85.166.194]:51170 "EHLO mail-it1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727650AbfACOSW (ORCPT ); Thu, 3 Jan 2019 09:18:22 -0500 Received: by mail-it1-f194.google.com with SMTP id z7so45396322iti.0 for ; Thu, 03 Jan 2019 06:18:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=p+jVw7m1VkU55Z+h4vl73u59DzM+akbkAL24Sfw8S3w=; b=L5xO1kq4T/nMKepbB02U3sVRnVdRIO/ECLd/mPXPnktVzn9jS1Lpj6Xq2p/g6cKKXr d0EXpUEMx3eWSNpzDs6EcCQ15Be5ANXCMoRBR+SOPxN1SCmCnJJvodfRiJ30OuQSo7ye 4TyWZnedDKSr/EWsyVht12SVqXYmh/+veTOmvvwmnL7mF6UkJiPUbsNlZr4mdRDrFKa+ d80f1SyLiZezK7Z/nrerVPI989v3ol6+bN6zQ4kbZak6x9ch21yAPtnvgsOZroA9oLOU JjZVpj4Kaqjd0rPFAGUyTcc39hs/566UNdJkaEBtCFnwHZraLnIkx3b09yGpXsvlekug grFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=p+jVw7m1VkU55Z+h4vl73u59DzM+akbkAL24Sfw8S3w=; b=Kf3DB3tOYDIynqnuoagXah54hP88aPsAuaXLlLoaMByf3SWPCrf/DN4+BNCcnq+Gma 5s79cqQF7cKZshHC3feSCbTGeohWOcMDa8V9SyVIba5+2Elau6bVY/UaHQC4POgtINB8 qQ8Nvp2CvfdNpNBo8mWUuMzTh1xDgPwFQcBHeXqWKaCOii5DYKE/ZDAf+EbVqC0y2H+K hOmaN3gU9OBW+BVuCcbEmss4nd/Lq6kuzS/ZcYrOv2OdoAJrzP3x5U4GD+ATTAJWfYSy eDtFogJeQRva9rY+3FyOy9/XlaFb9FCopSg0v0wul7qj+WJ15fywB9zocjXjtqoDQzOZ 67Gg== X-Gm-Message-State: AA+aEWaPZl57zr+t32pRINoaNi1XmCFlRFbN4mEXU8RFC47/DsgXXP0/ u7lnM84cvmKwlqZZgSDC2h2R9gU0tg== X-Google-Smtp-Source: AFSGD/VXoI224Db8NldVtvrDS6JDF/Sps5OqLv5SSRGqR8+hVU+zh9hSrsI0mFJzN+ok7PgAFGGg4g== X-Received: by 2002:a02:1217:: with SMTP id i23mr32642395jad.53.1546525101594; Thu, 03 Jan 2019 06:18:21 -0800 (PST) Received: from localhost.localdomain (c-68-40-189-247.hsd1.mi.comcast.net. [68.40.189.247]) by smtp.gmail.com with ESMTPSA id h64sm24472886itb.14.2019.01.03.06.18.20 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 03 Jan 2019 06:18:21 -0800 (PST) From: Trond Myklebust X-Google-Original-From: Trond Myklebust To: J Bruce Fields Cc: linux-nfs@vger.kernel.org Subject: [PATCH] SUNRPC: Don't allow compiler optimisation of svc_xprt_release_slot() Date: Thu, 3 Jan 2019 09:17:12 -0500 Message-Id: <20190103141712.24381-1-trond.myklebust@hammerspace.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Use READ_ONCE() to tell the compiler to not optimse away the read of xprt->xpt_flags in svc_xprt_release_slot(). Signed-off-by: Trond Myklebust --- net/sunrpc/svc_xprt.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 51d36230b6e3..94d344325e22 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -363,9 +363,11 @@ static void svc_xprt_release_slot(struct svc_rqst *rqstp) static bool svc_xprt_has_something_to_do(struct svc_xprt *xprt) { - if (xprt->xpt_flags & ((1<xpt_flags); + + if (xpt_flags & (BIT(XPT_CONN) | BIT(XPT_CLOSE))) return true; - if (xprt->xpt_flags & ((1<xpt_ops->xpo_has_wspace(xprt) && svc_xprt_slots_in_range(xprt)) return true; -- 2.20.1