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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FUZZY_BITCOIN,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 7F9C4C433E0 for ; Tue, 16 Mar 2021 22:15:39 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 138E964E86 for ; Tue, 16 Mar 2021 22:15:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 138E964E86 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34826 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lMHyU-00073N-3V for qemu-devel@archiver.kernel.org; Tue, 16 Mar 2021 18:15:38 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40728) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lMHqm-0005dM-On for qemu-devel@nongnu.org; Tue, 16 Mar 2021 18:07:40 -0400 Received: from mail-qk1-x734.google.com ([2607:f8b0:4864:20::734]:46246) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1lMHql-0002aR-1v for qemu-devel@nongnu.org; Tue, 16 Mar 2021 18:07:40 -0400 Received: by mail-qk1-x734.google.com with SMTP id a9so36922410qkn.13 for ; Tue, 16 Mar 2021 15:07:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=J1tKnZ+Z5Gv/Sv3p+d07e5sPy6aVH49CJw3OiYMO5w8=; b=lcRy+e895cMBOA2tKqV+iD5+Q846OBuz87DmOtpKXoxvxXoWW5cp0NwCZCL+MNpCqJ DxuHQwiNXawnSPNwlgvpl3nYmjfrdJuBidrnpNBlhIartT5GeK4fFSGiBXTp2g98Uv0Y isg9FGxpa2GSa47KjN2z/Je2GXcjm4Kv5YpzVcU8WCY5HBqNvelntby4pTMg9ze7sbU5 KlthFpd0OIUhPkP1B4nTDbN20Amz67+TYKVcm2dPlRmdvLNKh6t2Tyig7HAgrzsEQrxA 1RMGiuA5kZSOT9kfNlE1K5BUqI/zLqpOy2NZZF+T3KmwD7bJEOv3MgMGm9Fd2trM+IuX Tg6Q== 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=J1tKnZ+Z5Gv/Sv3p+d07e5sPy6aVH49CJw3OiYMO5w8=; b=HqSbtZVxvxkotxpxCFzSfGugmtiLm0eTV7Zn7e030vmyiu+Y7fPrtHEXZXQzzfc85D o+zLAKnzAL2KwtOVrK1aRG15o4AB7fkc9tgXUYsZ1b0NLYbFSlPp/igNGWUBC+OegTlB jlMBJD3O3PdqFiXsz/WMpim+6pPdorJTBSGn3Of2zbTfKP7CGCeqYkKnxLmYgWVzLG0b PQ9AmbD+ZuKdAuD3feTZaTyytiM+wAjtsxFvYB4e0bw0/rOwxISYoIb3XnFJzwn+mFDa oaSF9/N0yjgV50rz1mscnOloltc1X7hDiK2+/YJ3eOBx1MXrRVwKgCaCcN2pmiF4a+4E nlPA== X-Gm-Message-State: AOAM532vLlfRcqQ4JBIF5zQsRaad04k0NF+FXWZstnpxhngfOybVJKPc qEQjjrdJR/O63/EKff3zQNLwhHxpE3JK5yXj X-Google-Smtp-Source: ABdhPJzEUxBxbbSJK9j14GE38mn7AP7g1IDRhopMGpSVLC5m2RlvzA/dfVKZjmIcO5VujJvvMeajvQ== X-Received: by 2002:a05:620a:1528:: with SMTP id n8mr1289307qkk.329.1615932457780; Tue, 16 Mar 2021 15:07:37 -0700 (PDT) Received: from localhost.localdomain (fixed-187-189-51-144.totalplay.net. [187.189.51.144]) by smtp.gmail.com with ESMTPSA id n77sm16546918qkn.128.2021.03.16.15.07.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Mar 2021 15:07:37 -0700 (PDT) From: Richard Henderson To: qemu-devel@nongnu.org Subject: [PATCH 0/5] tcg: Issue memory barriers for guest memory model Date: Tue, 16 Mar 2021 16:07:30 -0600 Message-Id: <20210316220735.2048137-1-richard.henderson@linaro.org> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::734; envelope-from=richard.henderson@linaro.org; helo=mail-qk1-x734.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FUZZY_BITCOIN=0.007, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peter.maydell@linaro.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This is intending to fix the current aarch64 host failure for s390x guest cdrom-test. This is caused by the io thread issuing memory barriers that are supposed to be matched by the vcpu, but are elided by tcg in rr mode as "unnecessary". I know Peter would like a smaller patch to sync the io thread with the vcpu thread. I've made a couple of attempts at this, but havn't managed to get something reliable (although now irritatingly infrequent -- about 1 in 500). I have further patches to further optimize barriers, and to generate load-acquire/store-release instructions in tcg. But it's late in the release cycle, etc etc. I've done nothing to measure the performance impact of this. I quit the cdtom-test cycle after 4000 passes. r~ Richard Henderson (5): tcg: Decode the operand to INDEX_op_mb in dumps tcg: Do not elide memory barriers for CF_PARALLEL tcg: Elide memory barriers implied by the host memory model tcg: Create tcg_req_mo tcg: Add host memory barriers to cpu_ldst.h interfaces include/exec/cpu_ldst.h | 7 ++++ include/tcg/tcg.h | 20 +++++++++++ accel/tcg/cputlb.c | 2 ++ accel/tcg/tcg-all.c | 6 +--- accel/tcg/user-exec.c | 17 +++++++++ tcg/tcg-op.c | 19 +++++----- tcg/tcg.c | 79 +++++++++++++++++++++++++++++++++++++++++ 7 files changed, 137 insertions(+), 13 deletions(-) -- 2.25.1