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=-9.6 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 D9CF5C433DF for ; Thu, 2 Jul 2020 07:56:29 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 898B020772 for ; Thu, 2 Jul 2020 07:56:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PCTOgeyX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 898B020772 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 49y9Qg5sKHzDqVb for ; Thu, 2 Jul 2020 17:56:27 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::1044; helo=mail-pj1-x1044.google.com; envelope-from=npiggin@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=PCTOgeyX; dkim-atps=neutral Received: from mail-pj1-x1044.google.com (mail-pj1-x1044.google.com [IPv6:2607:f8b0:4864:20::1044]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 49y9GB1dWtzDqKl for ; Thu, 2 Jul 2020 17:49:06 +1000 (AEST) Received: by mail-pj1-x1044.google.com with SMTP id o22so7113983pjw.2 for ; Thu, 02 Jul 2020 00:49:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=fa9T6PNML2/xkl0bGh/Ztj2VCHxJI+rGnDXzulQp9g4=; b=PCTOgeyXmxCRHqkPbdWbNCD5RF4HWZdbQyTIojx6EjkOEWF+8/wPlG+BElrR7+YXPZ sLjTHouTQD0P60dVOilWpe+9ScH0g0t3DQfrJjVACgVsaQop6YHakwMXx0bTb/i9Kpyr IfE7/orhNh+x85icci2L+rRczXIMxKvjeObHUliBHpTheYNK4UHn2US9x2BpsMUNug+I EusvpjUPF/4LJKVp6u8AbSLcPZwrmIIEF3Y1b5zCKSh3qKcVdNqSh8SeyDBvoKorJgff xdbFqgnTG+Pi2peG6cNEYSMF+oKs2l5g3Bon66SblCaVCGRP5jxZmJeOVkncsl3jVmza hxSA== 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=fa9T6PNML2/xkl0bGh/Ztj2VCHxJI+rGnDXzulQp9g4=; b=mEV53sDFgc0Gb7PldosSu5T4kY4FoZqgJ+a717vTZG1hTjfEglptvJZMjV77T/jWR+ i7mvieAZMdzCs4SsL2lvJ7mEP/xZ5yI7TXh40hkj0FVTFe3VhkJq8hzzP8qsE1PNUpTN hX8/0d5PY4MQd1E/K0DL2eHLXhXgcc+F7dY74dwqhHbY2Gl8InD8DTwAdU6WUUrk/D6o bylVnLiu5Aew0OBAl8SJgXezKog+JJP2Hx3O6ocrfzE8amhAv/fEvT8mvdrgQs19tU95 o+f3tIxTiThTuVWWUNdIIBwnhGqXlC29KbqGrErCiEH91aHxGgh7EUZVHSBchXKbA+DF mIDQ== X-Gm-Message-State: AOAM531puh+gDdnMFdi7PtoyvwZ/oaHgvn/ZepDzr0FfNIQ4j2sE69Nr jpMQF80jjrd2D56R/n0b0Av7U5wb X-Google-Smtp-Source: ABdhPJz0DrYb1pN7ZPb0vDXXXEcS0FJvLihL6IDzUc7haMlJV7H/L6XRfoSOyJ9cS7kxACtRgiESpQ== X-Received: by 2002:a17:90a:950c:: with SMTP id t12mr32900004pjo.173.1593676144195; Thu, 02 Jul 2020 00:49:04 -0700 (PDT) Received: from bobo.ozlabs.ibm.com (61-68-186-125.tpgi.com.au. [61.68.186.125]) by smtp.gmail.com with ESMTPSA id 17sm6001953pfv.16.2020.07.02.00.48.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Jul 2020 00:49:03 -0700 (PDT) From: Nicholas Piggin To: Subject: [PATCH 2/8] powerpc/pseries: use smp_rmb() in H_CONFER spin yield Date: Thu, 2 Jul 2020 17:48:33 +1000 Message-Id: <20200702074839.1057733-3-npiggin@gmail.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20200702074839.1057733-1-npiggin@gmail.com> References: <20200702074839.1057733-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Peter Zijlstra , linuxppc-dev@lists.ozlabs.org, Boqun Feng , linux-kernel@vger.kernel.org, Nicholas Piggin , virtualization@lists.linux-foundation.org, Ingo Molnar , kvm-ppc@vger.kernel.org, Waiman Long , Will Deacon Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" There is no need for rmb(), this allows faster lwsync here. Signed-off-by: Nicholas Piggin --- arch/powerpc/lib/locks.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c index 6440d5943c00..47a530de733e 100644 --- a/arch/powerpc/lib/locks.c +++ b/arch/powerpc/lib/locks.c @@ -30,7 +30,7 @@ void splpar_spin_yield(arch_spinlock_t *lock) yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count); if ((yield_count & 1) == 0) return; /* virtual cpu is currently running */ - rmb(); + smp_rmb(); if (lock->slock != lock_value) return; /* something has changed */ plpar_hcall_norets(H_CONFER, @@ -56,7 +56,7 @@ void splpar_rw_yield(arch_rwlock_t *rw) yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count); if ((yield_count & 1) == 0) return; /* virtual cpu is currently running */ - rmb(); + smp_rmb(); if (rw->lock != lock_value) return; /* something has changed */ plpar_hcall_norets(H_CONFER, -- 2.23.0