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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 378B6C2D0A3 for ; Tue, 3 Nov 2020 21:34:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE8952072C for ; Tue, 3 Nov 2020 21:34:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604439261; bh=md9wSusj+UYDdkbmuUuq3AZ/paY7fC3MwE3iDZlR9iw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hdTZ6fsZ8llnwccv/hYyLD/YzEgSoNfRgQeeseYgoSYHCJUPeqO1QeD0s3fLEgzst ObOYUELp1VcruB/Kmn9yijYUFZfwA5TlkT0J/l8MqKoGKl1796HsPG2DWLF4JjJwR3 Nibff1KZ5Ra3F6ZhjJQYvZCl9yWUHzWHi1KiWUZ4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731929AbgKCVeS (ORCPT ); Tue, 3 Nov 2020 16:34:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:58628 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732252AbgKCU4k (ORCPT ); Tue, 3 Nov 2020 15:56:40 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C4E0820732; Tue, 3 Nov 2020 20:56:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604437000; bh=md9wSusj+UYDdkbmuUuq3AZ/paY7fC3MwE3iDZlR9iw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tWg0sLoDWfhAL7xDQfo9eD6/5QY5H92dW7qehbraRJDPWP1tW1RNEjXHKJDfeTxKZ DMFq1LG0WRpTi0q1iQ49suN/YcOexndF2KzVimBwGk8GMY+O8//qbI5QXCVfNs5AdC Cw6fBktuV/qSSWNp4n3/RwzFtUYm4MUGEv88s9Po= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kim Phillips , "Peter Zijlstra (Intel)" Subject: [PATCH 5.4 102/214] perf/x86/amd/ibs: Dont include randomized bits in get_ibs_op_count() Date: Tue, 3 Nov 2020 21:35:50 +0100 Message-Id: <20201103203300.110510920@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203249.448706377@linuxfoundation.org> References: <20201103203249.448706377@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kim Phillips commit 680d69635005ba0e58fe3f4c52fc162b8fc743b0 upstream. get_ibs_op_count() adds hardware's current count (IbsOpCurCnt) bits to its count regardless of hardware's valid status. According to the PPR for AMD Family 17h Model 31h B0 55803 Rev 0.54, if the counter rolls over, valid status is set, and the lower 7 bits of IbsOpCurCnt are randomized by hardware. Don't include those bits in the driver's event count. Fixes: 8b1e13638d46 ("perf/x86-ibs: Fix usage of IBS op current count") Signed-off-by: Kim Phillips Signed-off-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 Signed-off-by: Greg Kroah-Hartman --- arch/x86/events/amd/ibs.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -335,11 +335,15 @@ static u64 get_ibs_op_count(u64 config) { u64 count = 0; + /* + * If the internal 27-bit counter rolled over, the count is MaxCnt + * and the lower 7 bits of CurCnt are randomized. + * Otherwise CurCnt has the full 27-bit current counter value. + */ if (config & IBS_OP_VAL) - count += (config & IBS_OP_MAX_CNT) << 4; /* cnt rolled over */ - - if (ibs_caps & IBS_CAPS_RDWROPCNT) - count += (config & IBS_OP_CUR_CNT) >> 32; + count = (config & IBS_OP_MAX_CNT) << 4; + else if (ibs_caps & IBS_CAPS_RDWROPCNT) + count = (config & IBS_OP_CUR_CNT) >> 32; return count; }