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=-5.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 A4F08C04AB6 for ; Tue, 28 May 2019 12:56:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F1642081C for ; Tue, 28 May 2019 12:56:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ju/o2maT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727051AbfE1M4V (ORCPT ); Tue, 28 May 2019 08:56:21 -0400 Received: from merlin.infradead.org ([205.233.59.134]:49864 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726925AbfE1M4V (ORCPT ); Tue, 28 May 2019 08:56:21 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=DRQ/H105p5/3a63H0dgbNKZg2aY/zu92xXWVVrC1LWw=; b=ju/o2maTvwBbImtbPNLh5QpOs Ud8JYiA5IV0MawILTrpNnLHBKTVUTLj+dkHvixv1BSr4gj8t3E8I8T+p5b2e4051Ov2Rg/KYWm1QJ zz7QFpZVaJCPThFVl+uIQIEqbJVsJH07M3xUW6GYJC35fwaag7xgEz2niYaoSNj8Jw0bsI0Wp7ztD 3Ly8l+EKaOczZqqft4/KMXSFc79MrLn4U/u4HiIThMVx+se3zVPMbhZwYsA5VbgFrB6j6G4ESWe2H mQUllMiNAy54MetyWYKThQnWHifRSnrZtB8lYJaelStrfoL0QxG4k23gME+0NWuq6cPkJrkhlgjee 3oI2GYtlQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hVbeK-0003rv-Kv; Tue, 28 May 2019 12:56:16 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 6CC7520729088; Tue, 28 May 2019 14:56:15 +0200 (CEST) Date: Tue, 28 May 2019 14:56:15 +0200 From: Peter Zijlstra To: kan.liang@linux.intel.com Cc: acme@kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, jolsa@kernel.org, eranian@google.com, alexander.shishkin@linux.intel.com, ak@linux.intel.com Subject: Re: [PATCH 4/9] perf/x86/intel: Support hardware TopDown metrics Message-ID: <20190528125615.GW2606@hirez.programming.kicks-ass.net> References: <20190521214055.31060-1-kan.liang@linux.intel.com> <20190521214055.31060-5-kan.liang@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190521214055.31060-5-kan.liang@linux.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 21, 2019 at 02:40:50PM -0700, kan.liang@linux.intel.com wrote: > diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c > index e9075d57853d..07ecfe75f0e6 100644 > --- a/arch/x86/events/core.c > +++ b/arch/x86/events/core.c > @@ -91,16 +91,20 @@ u64 x86_perf_event_update(struct perf_event *event) > new_raw_count) != prev_raw_count) > goto again; > > - /* > - * Now we have the new raw value and have updated the prev > - * timestamp already. We can now calculate the elapsed delta > - * (event-)time and add that to the generic event. > - * > - * Careful, not all hw sign-extends above the physical width > - * of the count. > - */ > - delta = (new_raw_count << shift) - (prev_raw_count << shift); > - delta >>= shift; > + if (unlikely(hwc->flags & PERF_X86_EVENT_UPDATE)) > + delta = x86_pmu.metric_update_event(event, new_raw_count); > + else { > + /* > + * Now we have the new raw value and have updated the prev > + * timestamp already. We can now calculate the elapsed delta > + * (event-)time and add that to the generic event. > + * > + * Careful, not all hw sign-extends above the physical width > + * of the count. > + */ > + delta = (new_raw_count << shift) - (prev_raw_count << shift); > + delta >>= shift; > + } > > local64_add(delta, &event->count); > local64_sub(delta, &hwc->period_left); > @@ -1186,6 +1194,9 @@ int x86_perf_event_set_period(struct perf_event *event) > if (idx == INTEL_PMC_IDX_FIXED_BTS) > return 0; > > + if (x86_pmu.set_period && x86_pmu.set_period(event)) > + goto update_userpage; > + > /* > * If we are way outside a reasonable range then just skip forward: > */ > @@ -1234,6 +1245,7 @@ int x86_perf_event_set_period(struct perf_event *event) > (u64)(-left) & x86_pmu.cntval_mask); > } > > +update_userpage: > perf_event_update_userpage(event); > > return ret; *groan*.... that's pretty terrible.