From patchwork Mon Nov 9 12:54:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 322601 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=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 80F5AC2D0A3 for ; Mon, 9 Nov 2020 13:39:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3325F206B2 for ; Mon, 9 Nov 2020 13:39:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604929162; bh=fI+5mHMrsyBSYeS0TcfDWgCZOtJe5ty/pw3ywc610SY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=VytwQ9rCryZc6NNvtqOohzOeWmDg6FEqJkGKYzUiUaZu9aUxM4nhb6uZrtYc77XcL 4BN6E4lMdfMIu+ZTubQIE8vsSEhwaptbFMAr/FTeOaVYd5/KZn2fkp70Zmi66w/M5s cXdboyumJ1Uu85o5N1Nx9DEJIr2IZyY79kqpkDgE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730858AbgKINjU (ORCPT ); Mon, 9 Nov 2020 08:39:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:56084 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730634AbgKINCN (ORCPT ); Mon, 9 Nov 2020 08:02:13 -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 AED7620684; Mon, 9 Nov 2020 13:02:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604926932; bh=fI+5mHMrsyBSYeS0TcfDWgCZOtJe5ty/pw3ywc610SY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ppjwjgzw2qXwhKMxbbG6krVDfFCCRFZ0/S8lCh+cp1W/w0WN/s0D8h9bFkPVdXSCR C5CyNsxtDbign6CcI18AWjhIi0/L/5agZL+qOl52Khq6EsqDl6ubFm5zIDSu8uyiPY XlxpELXBSZwoYrQMIQdd+S67rIVNRb6Kp7aV0nrw= 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 4.9 046/117] perf/x86/amd/ibs: Dont include randomized bits in get_ibs_op_count() Date: Mon, 9 Nov 2020 13:54:32 +0100 Message-Id: <20201109125027.851885740@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201109125025.630721781@linuxfoundation.org> References: <20201109125025.630721781@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -346,11 +346,15 @@ 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; }