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=-3.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_MED, 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 CE462FD21E1 for ; Mon, 30 Jul 2018 14:28:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7BD5920873 for ; Mon, 30 Jul 2018 14:28:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=dugeo-com.20150623.gappssmtp.com header.i=@dugeo-com.20150623.gappssmtp.com header.b="XQk5Acn7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7BD5920873 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=dugeo.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731816AbeG3QDj (ORCPT ); Mon, 30 Jul 2018 12:03:39 -0400 Received: from mail-pf1-f181.google.com ([209.85.210.181]:43241 "EHLO mail-pf1-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726843AbeG3QDi (ORCPT ); Mon, 30 Jul 2018 12:03:38 -0400 Received: by mail-pf1-f181.google.com with SMTP id j26-v6so4610674pfi.10 for ; Mon, 30 Jul 2018 07:28:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dugeo-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id; bh=JWwN8suPm5zubfM9g+3+yJJ7cZkayLlzKQEkaJHlqs8=; b=XQk5Acn7USBenABNlMe18Vk9EhiypDdAbtIeBRya4EnM04yv5FgHO7y+32pu+iLdP2 V6fFKGhdL30wNTiHhuhJjUpY6MXYKPSwsW+zF4H3ixsg8s+/s+Hz4RUpTweVLOnM1ZTy Z5qCcE8aIOu6QIr3290864XSLk7dX23Z25tC+E76WkMI/OJ1T+rdG/zxuzUGgccjcIww GKPGgQESJbn4ol/+bG5vC4J6bobkA8IrdIGaKtl+SupOk7zAz8tYY061VsqgTyJHFvmu hdP3DYZnvUr6C1EN/fBbaPQrXzPBiH/BeE3JDlGFpo+/3TOGqiXwuV/oIb1/rrQlaJD2 W+NQ== 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; bh=JWwN8suPm5zubfM9g+3+yJJ7cZkayLlzKQEkaJHlqs8=; b=GZNQmuIzt+kZ3colEA1XQMS2oSK6GLnbTTwDL/vDiVGRJOOLW+TV2c3w/1nfNXlT1A 6G5as57sS6gaEyEZpZ7c9rJgMjqhd3k4TuQbgd2rAQMFNo9Vr8FELhkd3FyW0qWz/9pZ kjmbFtftdl4zpMZm1JZ3VloHkCDKRvk3Gg7ICyYtWlCF+z0btFw3zOX4it/xPUa0nn3W /On3a4zi86pGGhN8xXdOFE2XSQScP+TGHJnXEJBqbYMOBbu55xvvu66xco7sLIGfgbKl 7B5HUxN2+0W8CRiOVjGIX+b+GoPqQR4KjApuflvwLynAYbFH3ci2ZFgAuaFL9cSXHoRR 2Zvw== X-Gm-Message-State: AOUpUlEZiaGPYrgV1/N2T6ipXEvK022u9JLohlG45YO4otdTZCdz2gQ4 BIb5TtakDEeqHfYLflp2+12VXQ== X-Google-Smtp-Source: AAOMgpdmmofBsbM81Qt431N1ifhZwY8R8mNB+6dPjUJSGzWfp6tK4rIKqAya2ym110AikeJvMCGHZw== X-Received: by 2002:aa7:88d3:: with SMTP id p19-v6mr18120745pfo.160.1532960902934; Mon, 30 Jul 2018 07:28:22 -0700 (PDT) Received: from bud178.dugeo.com ([116.212.202.58]) by smtp.gmail.com with ESMTPSA id s3-v6sm31836371pfg.2.2018.07.30.07.28.19 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 30 Jul 2018 07:28:21 -0700 (PDT) From: Jacek Tomaka To: peterz@infradead.org, linux-kernel@vger.kernel.org, mingo@redhat.com, tglx@linutronix.de Cc: Jacek Tomaka Subject: [PATCH v2] perf/x86/intel: Add support for MISPREDICT bit on Knights Landing cpus Date: Mon, 30 Jul 2018 22:28:13 +0800 Message-Id: <20180730142813.13451-1-jacekt@dugeo.com> X-Mailer: git-send-email 2.17.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jacek Tomaka Problem: perf did not show branch predicted/mispredicted bit in brstack. Output of perf -F brstack for profile collected Before: 0x4fdbcd/0x4fdc03/-/-/-/0 0x45f4c1/0x4fdba0/-/-/-/0 0x45f544/0x45f4bb/-/-/-/0 0x45f555/0x45f53c/-/-/-/0 0x7f66901cc24b/0x45f555/-/-/-/0 0x7f66901cc22e/0x7f66901cc23d/-/-/-/0 0x7f66901cc1ff/0x7f66901cc20f/-/-/-/0 0x7f66901cc1e8/0x7f66901cc1fc/-/-/-/0 After: 0x4fdbcd/0x4fdc03/P/-/-/0 0x45f4c1/0x4fdba0/P/-/-/0 0x45f544/0x45f4bb/P/-/-/0 0x45f555/0x45f53c/P/-/-/0 0x7f66901cc24b/0x45f555/P/-/-/0 0x7f66901cc22e/0x7f66901cc23d/P/-/-/0 0x7f66901cc1ff/0x7f66901cc20f/P/-/-/0 0x7f66901cc1e8/0x7f66901cc1fc/P/-/-/0 Cause: As mentioned in Software Development Manual vol 3, 17.4.8.1, IA32_PERF_CAPABILITIES[5:0] indicates the format of the address that is stored in the LBR stack. Knights Landing reports 1 (LBR_FORMAT_LIP) as its format. Despite that, registers containing FROM address of the branch, do have MISPREDICT bit but because of the format indicated in IA32_PERF_CAPABILITIES[5:0], LBR did not read MISPREDICT bit. Solution: Teach LBR about above Knights Landing quirk and make it read MISPREDICT bit. --- arch/x86/events/intel/lbr.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index cf372b9055..043aa09f3a 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -19,7 +19,7 @@ enum { LBR_FORMAT_MAX_KNOWN = LBR_FORMAT_TIME, }; -static const enum { +static enum { LBR_EIP_FLAGS = 1, LBR_TSX = 2, } lbr_desc[LBR_FORMAT_MAX_KNOWN + 1] = { @@ -1230,4 +1230,8 @@ void intel_pmu_lbr_init_knl(void) x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = snb_lbr_sel_map; + + /* Knights Landing does have MISPREDICT bit */ + if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_LIP) + lbr_desc[LBR_FORMAT_LIP] |= LBR_EIP_FLAGS; } -- 2.17.0